The effects of low temperature applications on dormancy of Salvia verticillata L. and Rumex crispus L. seeds

The effect of low temperature was studied to break the seed dormancy of Salvia verticillata L. and Rumex crispus L. seeds. S. verticillata and R. crispus seeds collected in 2017 and 2018 were kept in deep freezer at -80°C for certain periods time. Some of the seeds of both the species were soaked in hot water at 90°C for 5 seconds but some others were left untreated. Germination tests were performed in dark at 20 ±1 ⁰C according to randomized plots design with four replications. Seed germination rates and germination performance (time) were calculated. The highest germination in S. verticillata was obtained from the seeds collected in 2017 (57%) and 2018 (67%) which were kept in deep freezer at -80°C for 4 days and were left untreated. The highest germination rate in R. crispus was obtained from the seeds collected in 2017 (83%) which were kept in deep freezer at -80°C for 1 day and were planted without any treatment. Germination rate of fresh R. crispus seeds was found to be rather low.

Investigating the possible mechanisms involved in aluminum tolerance through analysis of transcriptome data from different genotypes of soybean

Aluminum is one of the main factors limiting crop growth in acidic soils, thus, revealing the mechanism involved in soybean aluminum resistance is an important measure in order to improve soybean yield in acidic soils. In this paper, we analyzed transcriptome data from different genotypes of soybean under aluminum stress and found that multiple genes may mediate differences in aluminum tolerance of different soybean genotypes. Through comparative analysis, we found that aluminum-tolerant soybeans had a higher organic acid metabolism compared to sensitive soybeans, while aluminum-tolerant soybeans suffered higher levels of oxidative stress compared to sensitive soybeans. The differences in root elongation of various genotypes of soybeans under aluminum stress is likely to be closely related to the changes in cell wall structural components, among which differential expression of genes encoding POD, PAL, PME, PGIP1, HRGPs and expansin and other enzyme genes plays a key role. These results provide a clear basis for further studies on the relationship between the cell wall and aluminum tolerance of soybeans and their regulation

Effects of irradiance on growth and morphophysiology in Catalpa bungei plantlets

With the aim of examining the effect of irradiance on growth and morphophysiology in Catalpa bungei, and its acclimation strategy to different shade intensity treatments, a pot experiment was conducted to determine the growth, morphological, and physiological parameters of C. bungei clone 008-1 plantlets under high (HI), medium (MI), and low (LI) irradiance levels, i.e. at approximately 80, 50, and 30% of full sunlight, respectively. Irradiance provoked significant and varied changes in phenotypic plasticity index (PPI) values for growth (ca. 0.44), morphology (ca. 0.37), and physiology (ca. 0.28). Shade treatments (MI and HI) reduced growth, biomass yield, crown leaf area per plant, expansion rate of newly emerged leaves and their size at the end of expansion (length, width, and area), specific leaf weight, net photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, transpiration rate, instantaneous water use efficiency, and δ¹³C values, whereas specific leaf area (SLA), leaf chlorophyll concentration, and leaf nitrogen (N) concentration were greatly decreased. MI did not affect maximum quantum yield of PSII (Fv/Fm) values; however, LI induced a significant decrease in Fv/Fm. Shaded plantlets generally had higher or similar non-structural carbohydrate (NSC) concentrations than HI plantlets. Overall, growth traits linearly decreased with decreasing irradiance, but morphological and physiological traits exhibited different dynamic trends. Our results showed that C. bungei coped with shade through morphophysiological adjustments, i.e. increasing SLA, leaf chlorophyll content, and NSC reserves; however, shade (ca. 30–50% full sunlight) still induced a significant reduction in plantlet growth due to photosynthesis restriction (MI: stomatal closure; LI: stomatal closure and lower photosystem II efficiency) and changes in NSC allocation strategy, preferring to maintain metabolism and survival rather than growth investment.

Studies on germination ecology and seedlings characteristics of Cleome viscosa as affected by various environmental factors

Knowledge about weed seed germination is essential for its control. By knowing the weed response to various environmental factors are helpful for weed management without the use of herbicides. The aimed of present study was to know the impact of several environmental related factors on germination and seedlings characteristics of Cleome viscosa under laboratory conditions. The temperature suitable for germination of C. viscosa was 30°C where 81.25% seed germination occurred. However, no or little germination was observed at 15 and 20^oC, respectively. The germination of C. viscosa improved significantly from 5-7 pH, thereafter a decline was observed at pH 8 and 9 and completely inhibited at pH 10. Seed germination was somewhat salinity tolerant and germination observed at 250 mM NaCl (23.75%) which is much high but it was vulnerable to osmotic potential which completely prevented at -1.0 MPa. Seedling emergence responds substantially to burial depth. The seedling emergence was highest (87.5%) when seed retained at the surface of the soil and reduced to 30% at 4 cm depth. The germination and seedlings traits i.e. time to start germination, mean germination time (MGT) and time taken to 50% germination (T₅₀) germination index (GI) as well as root and shoot length, fresh and dry weight were affected significantly with all the studied environmental factors. The results obtained in this study will be useful to develop a comprehensive management program to control C. viscosa.

Effects of different concentrations of potassium chloride on some growth parameters of Solanum melongena L.

This study was aimed to find the effects of various molar concentrations of KCl (0.1M, 0.2M, 0.3M and 0.4M) on some growth parameters of Solanum melongena L. (eggplant). The parameters included stem height, leaf length, number of leaves, fresh and dry weight of plant, width of leaf and length of root index were investigated. The plant which is subjected to the highest concentration of KCl drastically effects the plant life cycle as well as productivity of plant. Much of the healthy and strongest plant is formed in control condition as compare to these which received KCl with different concentration. Salinity stress significantly decreased average height of shoot i.e. 30.53cm in control while the least i.e. 10.2cm at 0.4 conc. of KCl. Similarly, average number of leaves i.e. 17.43cm in control while the least i.e. 5.01 at 0.4 conc. of KCl. Likewise average length of leaf i.e. 18.04cm in control while the least i.e. 9.96cm at 0.4 conc. of KCl. Average Fresh and dry weight of plant i.e. 27.96g and 9.12g respectively in control while the least i.e. 7.01g and 2.025g at 0.4 conc. of KCl. Similarly average width of leaf i.e. 7.88cm in control while the least i.e. 3.88cm at 0.4 conc. of KCl. Likewise average length of root i.e. 18.75cm in control while the least i.e. 6.90cm at 0.4 conc. of KCl. These indexes show the same response to different concentration of KCl which means that the concentration and the response of the above indexes are inversely proportional to each other. Greater the concentration of KCl lower will be the response of the above indexes and vice versa. It was concluded that different growth parameters of the eggplant were affected adversely along increased treatments of KCl

Enhancing drought tolerance in Camelina sativa L. and Canola napus L. through application of selenium

Considering the burning issue the present study was undertaken in pot culture at the Cholistan Institute of Desert Studies (CIDS), The Islamia University of Bahawalpur, Pakistan for enhancing drought tolerance in two oilseed crops (OC) crops camelina (Camelina sativa L.) and canola (Canola napus L.) through improving physiological, biochemical, and antioxidants activity by foliar application of selenium (Se) under drought stress. Two Camelina (i.e., ‘Australian Camelina’ and ‘Canadian Camelina’) and canola genotypes (i.e., ‘AARI Canola’ and ‘UAF Canola’) were used as plant materials during the growing season of 2016. Both Camelina and Canola genotypes were grown under normal (100% FC) and water deficit (drought stress) (40% FC) conditions. Four levels of Se: such as seeds priming with 75μM Se, foliar application of Se at 7.06 μM and foliar Se in combination with seeds priming (7.06 μM & 75μM) along with control were applied at the vegetative stage of both OC crops for screening drought tolerant genotypes. All treatments were arranged three times in a randomized complete block design. Both OC crops were grown upto the maturity and data on physiochemical, antioxidants and yield components were recorded during this study. Results of the present study indicated that the physio-biochemical parameters such as WP (water potential), OP (osmotic potential), TP (turgor pressure), proline, TSS (total soluble sugar), TFAA (total free amino acids), TPr (total proteins) and TS (total sugars); and total chlorophyll contents were improved by foliar application Se along with seed priming by Se in both OC crops in both drought stress and non-stress (control) conditions. Similarly, osmoprotectants such as GB (Glycinebetaine), anthocyanin, TPC (total phenolic contents) and flavonoids; as well as antioxidants such as APX (ascorbate peroxidase), SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) were also showed better enhancement in both OC crops through foliar application in combination with seed priming with Se (7.06 μM & 75μM) under normal as well as water deficit (drought) conditions. Yield and its components i.e., branches plant^-1 (no.), 1000-seed weight (g), seed and biological yield (t ha^-1) of both OC crops were increased through foliar application in combination with seed priming by Se (7.06 μM & 75μM) under drought and non-drought stress conditions. Both camelina and Canola genotypes categorized based on all the above-mentioned parameters under the water deficit (drought stress) condition and foliar application of Se, the genotype ‘Canadian Camelina’ maintained the highest values for all these attributes. Therefore, it is revealed that foliar application in combination with seed priming by Se helps to improve drought tolerance of OC crops and also leads to an increase in the productivity of crops under drought stress. Among the genotypes, ‘Canadian Camelina’ performed the best when seeds of the genotypes were primed with Se in combination with foliar application of Se at the vegetative stage. 

The effects of alkaline stress and developing stage on the magnitude of clonal integration in Leymus chinensis (Poaceae): an isotopic (¹⁵N) assessment

Clonal integration has been shown in many clonal plants to be influenced by stress and growth stage, but few studies have examined the magnitude of such influence. To quantify the transport of resources, glasshouse experiments were conducted by tracing the movement of ¹⁵N label between interconnected ramets to compare the effects of soil alkalinity and developing stages of Leymus chinensis apical ramets on clonal integration. The apical ramets were referred to as “pre-rooting” (those that have not rooted in the soil) and “post-rooting” (those that have rooted). We found that a low amount of ¹⁵N was transported from basal to post-rooting apical ramets, and ¹⁵N translocation significantly increased from basal to pre-rooting apical ramets. However, there were significant increases in ¹⁵N for both pre- and post-rooting stages when apical ramets were exposed to stress conditions. Moreover, severing their connections reduced apical ramet growth under stress conditions. Therefore, the magnitude of clonal integration is affected by the developing stage and environmental condition. In addition, clonal integration enhances the growth of apical ramets under pre-rooting stage and alkaline stress, but has relatively little effect on post-rooting apical ramets under no stress conditions. Alkaline stress also had a greater impact than the developing stage. Our study indicates that clonal integration might ameliorate negative effects of alkaline stress and growth stage through source-sink feedback regulation such as nitrogen. This may contribute greatly to the species to withstand local alkaline stress and successfully reproduce from pre- to post-rooting stages.

In-silico transcriptome study of the rice (Oryza sativa) strigolactone-deficient (dwarf17) mutant reveals a potential link of strigolactones with various stress-associated pathways

Strigolactones (SLs), the newest group of phytohormones, are involved in a wide range of functions, including the regulation of plant growth and physiology. Besides, emerging evidence suggests that SLs also participate in the promotion of plant environmental stress resilience through mediation of different metabolic genes/pathways. However, thus far little is known about SL-mediated transcriptional changes in rice (Oryza sativa), compared to other model plants. To meet this objective, we analyzed the RNA-seq-based comparative transcriptome data sets of rice SL-deficient dwarf17 (d17) mutant line and its respective wild-type (WT), obtained from the National Center for Biotechnology Information GenBank. Both, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, in order to identify genes/pathways which function downstream of SLs. With respect to the WT, a large number of functional GO terms, mainly stress-associated terms such as ‘response to stress’, ‘response to stimulus’, ‘response to chemical’, ‘response to oxidative stress’ and ‘reactive oxygen species metabolic process’ were significantly suppressed in the d17 mutant plants. In addition, KEGG metabolic pathways such as ‘valine, leucine and isoleucine degradation’, ‘plant hormone signal transduction’, ‘galactose metabolism’, ‘fatty acid degradation’ and ‘phenylalanine metabolism’ were also remarkably undermined in the d17 lines relative to the WT. These results imply a possible involvement of rice SLs in the regulation of distinct stress-related metabolic genes/pathways, which may function in environmental stress tolerance of plants. Taken together, the study provides new opportunities to broaden our limited understanding of SL-regulated downstream pathways, especially in rice

The effects of habitat degradation on phenology and reproduction of some species of genus Primula L.

Habitat degradation can significantly affect plant reproductive success. Genus Primula (Primulaceae; Primrose) depend on temperature and relative humidity of environmental factors. Some species of genus Primula flower before the forest starts leafing. Other species grow in subalpine and alpine meadows. The elevation range of studied habitats of Primula species in the Greater and East Caucasus is between 400 to 3000 meters: P. woronowii Losinsk. Grows in oak-hornbeam forests (400-1000 m); P. macrocalyx Bunge - in beech forest (900-1700 m); P. auriculata L. in  subalpine wet meadows (1800-2300 m); P. cordifolia Rupr. in subalpine meadows (1800-2300 m). P. amoena M. Bieb. grows in two different habitats: subalpine birch forest (1800-2300 m) and subalpine and alpine meadows (2300-2800 m); P. algida Adams occurs in  subalpine and alpine meadows (2300-3000 m). Seed production of two species (P. amoena and P. woronowii) were determined. We have calculated sky exposure. As a result reproductive effort of early flowering forest species of Primula shows close correlation to microclimatic conditions determined by sky exposition. In case of P. woronowii the limit index of sky exposition is 5%, below which the species does not develop flowers. Global climate change can cause shifts in "spring index" in forests and will change duration of phenological phases of Primula in shadow habitat. This will influence reproductive success of the species and determine the chances of its survival and propagation.

Salix viminalis males maintain higher photosynthetic capacity than females under high temperature stress

Sexual-specific photosynthetic responses to high temperature stress were investigated in the dioecious species, Salix viminalis. The males and females of S. viminalis were cultivated for 7 weeks in greenhouse, afterwards they were processed to high temperature in climate box. Half of the plants were exposed to 40^oC/30^oC (day/night temperature) which increased stepwise (5^oC every 48 h), while the other half were maintained at 25^oC /15^oC served as a control. Seven days later, photosynthetic physiological parameters in leaves of S. viminalis were analysed. The high temperature treatment caused significant reduction of net photosynthetic rate (P_N) in S. viminalis, but male plants showed obviously higher P_N than female plants. The F_v/F_m value was relatively stable and no obvious difference was detected between male and female plants, indicating the photosynthetic light reaction was not inhabited and both male and female plants possess functional PS II under high temperature. In photosynthetic carbon cycle, the activity of Rubisco declined and the higher activity of the enzyme in males than females revealed that inhibition of photosysthesis occurred and the photosysthesis in males were less inhibited under high temperature. In addition, Carotenoids (Car) content increased and the content of male plants was higher than that of females, which stated that the high temperature could cause photoprotective response and the photoprotection ability were stronger for males. These findings suggest that male plants of S. viminalis could maintain higher photosynthetic capacity under high temperature stress, thus male plants should be selected when breeding heat-resistance species according to photosynthetic parameters.

Agronomical and physiological perspectives for identification of wheat genotypes for high temperature tolerance

High temperature is one of the major limiting factors in wheat (Triticum aestivum L.) production in arid and semiarid regions of world. The crop experiences moderate to severe high temperature at most of its growth and physiological stages of growth. A glass house experiment was conducted to investigate the impact of high temperature on growth and productivity of wheat crop under different sowing regimes. Seventeen wheat genotypes were sown under two sowing dates with interval of thirty days in cemented bed filled with river sand. Results showed that high temperature stress due to late sowing has negatively influenced plant growth and yield by modulating physiological and biochemical attributes. Among the genotypes, NIA-AS-14-9, NIA-Sunder, Raskoh, TJ-83, Dani, Saher-2006 and SH-Salt-5B produced high plant biomass, productive tillers, number of grains and grain yield per plant under both sowing conditions. However, maximum relative water contents were observed in LU-26s while NIA-AS-14-10 showed better membrane stability and chlorophyll contents followed by NIA-Sarang, Kiran-95 and Dani under late sown conditions. NIA-Sunder, NIA-AS-14-10 and SRN-09111 had accumulated substantial proline contents but failed to produce significant amount of soluble sugars and glycine betaine (GB). These parameters showed higher accumulation for Dani, Saher-2006, Raskoh, Bathoor, TD-1 and Kiran-95 under high temperature stress. Overall results showed that genotypes SH-Salt-6, NRL-1236, NIA-Sarang, LU-26s and Dani were failed to cope effectively under high temperature stress conditions and illustrated poor performance

Performance of wheat genotype for morpho physiological traits using multivariate analysis under terminal heat stress

High temperature adversely affects the development and growth of wheat crop. It disturbs photosynthesis and transpiration due to canopy temperature and senescence of leaves that cause reduction in wheat grain yield. Genetic divergence among genotypes and suitable selection criteria is imperative for efficient breeding programs to develop tolerance against heat stress. Therefore, 158 wheat genotypes were evaluated under normal and delayed planting mediated heat stress. Current study revealed reduction in grain yield (42.41%), grains per spike (16.51%), photosynthetic rate (39.84% and 48.52%), transpiration rate (55.88% and 51.85%) at vegetative and reproductive stage respectively. Furthermore, cell membrane injury (11.4-52.0% and 10.4-32%), canopy temperature depression (15.5-10.8ºC and 11.3-6.1ºC) at vegetative and reproductive stage, leaf angle (6º-42º) and stay green (68.8-17.5) were observed from heat tolerant to susceptible genotypes. Principal component analysis indicated highest negative loading components viz., stay green followed by grain yield and canopy temperature depression at reproductive stage whereas positive loading component such as heat susceptibility index for grain yield that would be used as effective selection criteria against heat stress. Correlation analysis suggested that high values of stay green, thousand grain weight, grains per spike, photosynthetic rate, transpiration rate and proline content while low values of cell membrane injury, heat susceptibility index for grain yield and canopy temperature can improve grain yield. Cluster analysis characterized 158 wheat genotypes into three groups based on different physio-morphic traits. Cluster-III retained genotypes with high value for heat tolerance indices such as stay green, grain yield, canopy temperature depression at reproductive stage while least value of heat susceptibility index for grain yield those were selected in PCA. These results would enhance the efficiency and precision as selection criteria for improvement in wheat against heat stress.

Evaluation of the physiological and agricultural properties of some of the bread wheat (Triticum aestivum L.) genotypes registered in turkey using biplot analysis

This study was conducted over two years in the 2016-2017 and 2017-2018 growing seasons with 13 bread wheat varieties under rainfall condition of Diyarbakir province, Turkey. Trials were designed according to randomized blocks with three replications. Significant differences were determined in all investigated traits (p≤0.01). According to the results of correlation analysis, Grain yield (GY) had a significant positive relationship with heading time and plant height, and a significant negative relationship with protein rate, zeleny sedimentation, and wet gluten. The GGE-biplot analysis revealed the presence of six different sectors with the physiological properties and quality parameters being included in the same sector. It was remarkable that there was a significant negative relationship between hectoliter weight and chlorophyll content and normalized difference vegetation index. Dinc, Gelibolu, Kale, and Aday-12 were prominent genotypes in terms of GY. It was determined that the investigated genotypes showed better potential in the first year of the study, and Aday-12 was the most stable genotype for GY. Based on the results, flag leaf chlorophyll content (SPAD) and normalized difference vegetation index were revealed as important parameters to be considered in quality-based selection. It can be concluded that the genotypes Dinc, Gelibolu, Kale and Aday-12, having a high GY and acceptable quality values, could be recomended cultivated under farm conditions and used as parents in wheat breeding programs

Comparisons of weed suppression and strawberry yield obtained with organic and synthetic mulches and herbicides

An experiment was conducted to find the possibilities of weed suppression in strawberry through mulches and herbicides by observing fresh weed biomass and phenology of strawberry. The trial was laid out in RCB design at “New Developmental Farm” The University of Agriculture, Peshawar. Three different row-row spacing (30 cm, 60 cm and 90 cm) and eight different weed control strategies (Stomp (pendimethalin), Dual gold (S-metolachlor), Percept (haloxyfop-p-methyl), white plastic mulch, wheat straw mulch, saw dust mulch, hand weeding and weedy check) were used in the experiment. The results showed that maximum weed suppression was found for plots with hand weeding. However percept herbicide also caused low fresh weed biomass and dry weed biomass. Row spacing and different weed control methods significantly affected most of the growth and yield related parameters of strawberry. Results revealed that fresh and dry biomass were higher in wider row spacing (90 cm) in control plots. Whereas the minimum was deciphered for 30 cm row spacing and hand weeding treatment followed by Percept and white Plastic used as mulch. Data regarding fruit size showed that highest number of fruit size were noticed for 60 cm row spacing for hand weeding and percept treatments and less was noted at 90 cm row spacing in weedy checks. From the study we concluded that hand weeding in 60 cm row spacing along with application of herbicide Percept could be effective for the management of weeds in strawberry, similarly, use of white plastic as a mulch may decrease weeds infestation and improve yield of strawberry in agro-ecological conditions of Peshawar.

Changes of weed flora in cereal fields over the last 31 years in Van, Turkey

Agricultural activities carried out over time, and accordingly the developments in pest control methods, and climatic changes caused by the global warming affect the composition and density of weeds in agricultural areas. In order to determine and reveal the causes of this change, a survey was conducted on cereal fields in Van in 2017 and compared with the results of a 31 years old survey. A total of 71 weed species belonging to 23 plant families were identified in 2017, while 84 weed species belonging to 24 plant families were identified in 1986. Looking at the weed density in unit area, it was found that the weed averages were 41.8 in a square meter in 2017 and 82.8 in 1986. In both surveys, the number of weed species was almost equal to each other and the coefficient of Similarity Index (SI) for 2 surveys was calculated as 0.58 in terms of weeds. While the roughfruit corn bedstraw (Galium tricornutum Dandy.), tuberous cranesbill (Geranium tuberosum L.) and rye (Secale cereale L.) were detected as the most intensive species in 1986, the narrowleaf knotweed (Polygonum bellardii All.), goatgrass (Aegilops spp.) and summer pheasant's eye (Adonis aestivalis L.) were identified as the densest species in the recent study. When the weed distribution was assessed based on their abundances, the field bindweed (Convolvulus arvensis L.) with 21.3% frequency of occurrence and yellowweed (Boreava orientalisJaub. & Spach) with 19.5% frequency of occurrence were detected as the most common weeds in 2017. The field bindweed (Convolvulus arvensis L.) was the most common weed type in both studies, while the yellowweed was found to be common only in 2017. When both studies were compared, it was seen that the total weed density had decreased at a significant level during the last 31 years, although there had been significant increase in the density of several weeds, such as the yellowweed (Boreava orientalis Jaub. & Spach). It is considered that this decrease was due to the increase in cultivation and pest control techniques.

Association of arsenic fractions to arsenic in rice plants

Arsenic in rice fields of district Tando Mohammad Khan is a concern, most likely originating from long term canal irrigation water receiving significant quantities of wastewater. Evaluation of available soil arsenic through fractionation schemes can help understand the chemical association with elements and its transformation to rice.  In this study 120 soil samples, from 24 rice fields and associated rice shoots were collected from intensive rice cultivated area of the district. Fractionation schemes illustrated that most of the arsenic in soils was calcium-bound and available arsenic (water soluble + exchangeable), with some as iron and aluminum bound arsenic, contributing 38, 29, 17 and 10 percent to total soil arsenic. The regression equations further confirmed the significant contribution of each calcium-bound (r = 75), available (r = 65), iron-bound (r = 49) and aluminum-bound arsenic (r = 0.42) to rice grain. The same was true for straw + husk, however, the relationships were significant only in case of calcium-bound (r = 0.79) and available arsenic (0.48). Only 4 out of 24 sites were contaminated by soil arsenic (5.47-59.77 mg kg^-1) and 01 by grain arsenic (0.15-1.00 mg kg^-1), but concentration in straw + husk was more (0.30-1.29 mg kg^-1) than that in grain. In order to avoid further arsenic increase in rice soils, regular monitoring of arsenic in soil, rice grain and straw + husk may be carried out

Evaluation of karyotype, genome size and GC content in Dianthus chinensis L.

Dianthus chinensis is an important ornamental species in the genus Dianthus. Its high tolerance to biotic and abiotic stresses is beneficial for genetic improvements of Dianthus. In this paper, we conducted a karyotype analysis on mitotic chromosomes of D. chinensis. Its genome size (2C value) and GC content were measured by flow cytometry using propidium iodide (PI) and 4’, 6-Diamidino-2-phenylindole (DAPI) as dyes. The results showed that the D. chinensis has 2n = 2χ= 30 chromosomes. The chromosomes are metacentric or submetacentric. Their length varies from 1.60 ± 0.57 to 4.70 ± 0.85 µm. The estimation of its genome size is 772.53 ± 0.91 Mbp and GC content is 39.80 ± 0.12%. The cytological information of D. chinensis is helpful to clarify phylogenic relationships and assess potential plant transformation experiments among Dianthus species

An efficient micropropagation protocol via indirect organogenesis from callus of economically valuable crop date palm (Phoenix dactylifera L.) cultivars “Sagai and Khalas”

Regeneration of date palm cultivars (Khalas and Sagai) was achieved from callus by indirect organogenesis using different plant growth regulators (PGRs) on the modified MS culture medium. The best PGRs combination for the indirect induction of adventitious bud formation was observed at 4 mg BA/L + 0.5 mg/L of NAA in Khalas (4.50 buds) and 2 mg BA/L + 1 mg/L NAA in Sagai (8.75 buds). The multiplication of adventitious bud was found to be greater at a combination of PGRs (1 mg/L of 2iP + 0.5 mg/L of NAA) in Khalas (8 buds); and 4 mg 2iP/L + 0.5 mg NAA/L in Sagai (12.75 buds). The shootlet length (6.16 cm) was achieved at 5 mg/L GA₃ as compared to that at other GA₃ concentrations used in both cultivars. The highest number of roots (4.14 roots) from shootlets was achieved at 0.5 mg/L of NAA in cv. Sagai, whereas, in Khalas, the highest number of roots (3.28 roots) was formed at 1.5 mg/L of IBA. The highest root length (4.10 and 3.57 cm) was formed at 1.5 mg/L of IAA in both cultivars, respectively. Thus, the protocol developed through this investigation could be used at a wide scale for the production of high-quality plantlets to meet the demand of these date palm cultivars

Sulfur: a multifunctional element that improves nutritional value of maize grains

Sulfur is an integral constituent of various proteins, vitamins and essential nutrients necessary for maintaining plant growth and development under saline conditions. An experiment was conducted to assess the role of sulfur in improving nutritional quality of maize grains at varying levels of sulfur (40, 80 mM) and salinity (25, 75 mM). Various vitamins, biomolecules and nutrient contents were analyzed. A significant reduction in vitamins (ascorbic acid, tocopherol, riboflavin, niacin, thiamine), biomolecules (protein, carbohydrate, starch) and nutrient (K⁺, Ca²⁺, NO₃^-, PO₄^3-, SO₄^2-, K⁺/Na⁺, Ca²⁺/Na⁺) contents was observed by imposition of salinity. However, salinity increased Na⁺ contents at all applied salt levels. Application of 40 mM sulfur significantly improved ascorbic acid, tocopherol, riboflavin, niacin, thiamine, protein, carbohydrate, starch, K⁺, Ca²⁺, NO₃^-, PO₄^3-, SO₄^2-, K⁺/Na⁺, Ca²⁺/Na⁺, while Na⁺ contents were reduced by sulfur application. Salt tolerant maize variety (Agatti 2003) responded well to sulfur fertilization in comparison to salt sensitive maize cultivar (Pak Afgoi 2003). In short, both levels of sulfur (40, 80 mM) effectively reduced toxic effects of salinity by improving vitamins, biomolecules and nutritional contents in maize grains. However, 40 mM sulfur was found more effective in improving salt tolerance potential of maize plants.

Diurnal variation in physiological responses of aerobic-adapted rice varieties under different mulching strategies

Rice consumes more water compared to other crops. Therefore, rice varieties that are able to adapt non-flooded (aerobic) condition could be an advantage to conserve water. Furthermore, the ground cover rice production system using mulching technique can be effectively reduced water stress for aerobic rice cultivation. In this study, the diurnal physiological responses of aerobic-adapted Malaysian rice (Oryza sativa L.) varieties MRQ74 and MR253 were investigated under different mulching strategies, i.e. plastic mulch (PM), rice straw mulch (SM), and no mulch (NM). Photosynthesis rate (A), transpiration rate (E), stomatal conductance (g_s), water use efficiency (WUE) and stomatal limitation (L_s) were measured at tillering and maturation stages of the rice plants. The latter stage have shown significant differences (ANOVA, p≤0.05) on the parameters studied, in which A was highest in PM (197 µmol m^-2 s^-1) followed by SM (146 µmol m^-2 s^-1) and NM (86 µmol m^-2 s^-1) in MRQ74. Interestingly, the result showed a unimodal diurnal curve for A in both tillering and maturation stages, which indicates that the midday depression of A did not present. This suggests that the mechanism improves the ability of rice plant to adapt in aerobic condition. Furthermore, mulching treatments demonstrated an improved WUE on both MRQ74 and MR253 during maturation stage. At tillering stage, PM treatment increased WUE about 75% higher compared to NM during the midday. This study shows that mulching treatment such as PM and SM can be implemented to improve aerobic rice cultivation and subsequently sustaining rice production in water limited area.

Effect of drying-rewetting durations in combination with synthetic fertilizers and crop residues on soil fertility and maize production

Alternate wetting and drying boost decomposition of organic matter and various nutrient transformation processes to change the nutrient availability for plant uptake. Integrated nutrient management is important to reduce the use of synthetic fertilizers, sustain soil fertility and maize production. Repeated pots and two-year field experiments were conducted to estimate the effects of synthetic fertilizers and crop residues under different DRW (drying rewetting cycles). All fertilizer treatments caused remarkable increase in soil organic carbon (SOC), available nitrogen (AN), available phosphorus (AP), extractable potassium (K), maize chlorophyll content, maize dry biomass and grain yield, especially under 14 days of alternate wet dry cycles. Mung bean straw caused more increase in SOC, AN, AP, while½ NPK + ½ mung bean straw caused more increase in maize chlorophyll content and dry biomass. Maximum increase in soil K was observed with recommended NPK in both experiments. Significant effects regarding C/N ratio and soil pH were noted with the solo application of mung bean straw and rice straw_. Maximum increase in grain yield (20%) was achieved with ½ NPK + ½ mung bean straw. In conclusion, integration use of crop straw and inorganic fertilizers with alternate wetting and drying may help harvest better maize yield on sustainable basis. 

Taxonomic studies of pteridophytes of Utror valley, district Swat, Khyber Pakhtunkhwa, Pakistan

In the present study, an attempt has been made to collect and identify the Pteridophytes of Utror valley, Swat. During the survey 16 Pteridophytes belonging to 10 genera and 9 families are taxonomically and ethnobotanically described.  Dryopteridaceae was found as a dominant family having the largest number of species, i.e. 4 species belonging to the genus Dryopteris. Aspleniaceae was the second largest family in terms of number of species, i.e. 3 species belonging to the genus Asplenium. The families like Adiantaceae, Cystopteridaceae, Dennstaedtiaceae, Polypodiaceae, and Thelypteridaceae were represented by one species each, i.e. Adiantum venustum, Cystoperis fragilis, Pteridium aquilinum, Polypodium vulgare, and Cyclosorus dentatus, respectively. The study revealed that these ferns are used by the local community for the treatment of different health ailments.

Leaf architecture and its systematic significance in Aceraceae from China

Leaf architecture of 30 species representing 2 genera of Aceraceae in China was investigated for the first time. Within the 30 species, 10 species are found with an actinodromous venation pattern, while 20 species are found with a pinnate venation pattern. Within the 20 species with pinnate venation, 10 species are camptodromous, while the other 10 species are craspedodromous. Four types of leaf teeth are detected, viz. entire, toothed, lobed and partite. The secondary veins of most species are unbranched, except for Acer cordatum. Most species have obvious intersecondary veins, except for 4 species, i.e., Dipteronia sinensis, D. dyerana, Acer davidii and A. maximowiczii. All species have both reticulate and percurrent tertiary veins, except for A. pentaphyllum, which has only reticulate tertiary veins. All species are found with irregular areoles, except for A. pentaphyllum which is found to be regular. Veinlets are simple, branched or absent. A key to the genera and sections of Aceraceae mainly based on leaf architecture characters is presented.

Numerical taxonomic studies of the genus Cleome L. (Cleomaceae) from Pakistan

The genus Cleome L. was analysed numerically to find out the relationship of 11 species from Pakistan. Hierarchical clustering was performed by using Euclidean distance index and 214 characters from gross morphology, phenolic compounds, micromorphology of leaf, pollen, seeds and seed coat elements were taken into consideration. Results obtained by numerical data indicated the occurrence of two distinct groups. The group I comprised of 7 species viz., C. karachiensis, C. scaposa, C. brachycarpa, C. fimbriata, C. rupicola, C. viscosa and C. oxypetala and group II was represented by C. ariana, C. dolichostyla, C. pakistanica and C. spinosa. It was concluded that the group of species indicated the close affinity among them except that of the two morphologically allied species viz., C. karachiensis and C. viscosa which fell in separate groups. Which indicate that synthetic approach does not necessarily correlate with subjective findings

Genetic diversity and structure of Sinopodophyllum hexandrum populations in the Tibetan region of Qinghai-Tibet plateau, China

Sinopodophyllum hexandrum is a perennial herb with medicinal value for local Tibetans living in the Qinghai-Tibet Plateau (QTP), China. The species has been classified as endangered in the Chinese Plant Red Book because of the decline of wild resources and lack of artificial cultivation. For the conservation of resources in the Tibetan region of QTP, the genetic diversity and structure of S. hexandrum distributed in this area were investigated based on nuclear microsatellite molecular markers. All populations showed low genetic diversity. Genetic differentiation occurred mainly among populations JCX, MTS, and 10 others on Tibetan region of the QTP. Such genetic differentiation pattern might have been due to geographic isolation and lack of pollination in QTP. The strategies for conservation based on these results are suggested.

Colpate, colporate and porate pollen isolated from the Shale of Bara formation, Lakhra, Sindh, Pakistan

The paper describes some colpate and colporate fossil pollen grains from the carbonaceous shale belonging to Bara Formation located at Lakhra, Sindh, Pakistan. Fossil pollen were compared to nearest modern equivalents. The families akin to fossil pollen grains were mainly angiospermic. Based upon palynological analyses, the environment of deposition of Bara Formation was depicted of fresh water swampy environmentad adjoining to near shore sedimentation possessing sufficient fresh water supply.

Tree diversity patterns, above-ground biomass and carbon assessment along elevational gradient in a tropical forest of the Cameroon volcanic line

Tropical forests ecosystems remain the most diverse on the planet, and store considerable amounts of biomass and carbon. Despite the importance of tropical forests, sizable knowledge gaps exist regarding species diversity, plant biomass and carbon. These knowledge gaps are particularly large in tropical systems, and even more so in the African tropics. This study provides baseline data on species composition and vegetation structure, and evaluate variation along elevational gradient transecting of four elevation-forest types: lowland, mid-elevation, sub-montane and montane forest in the Rumpi Hills Forest Reserve of Cameroon. We collected data on tree species diversity, above-ground biomass and carbon in 25 1-ha plots sampled in 500 m long x 20 m width transect. Results revealed high species diversity, particularly in lowland forest. Overall, the study enumerated 12,037 individuals (trees ≥ 10 cm dbh) of 441 species. The mean species per plot decreased with increasing elevation, 112 in lowland, 81 in mid-elevation, 60 in submontane and 38 in montane forest. Above-ground carbon averaged 162.88±50 t ha^-1. We found the greatest carbon storage and tree and liana species diversity at low elevations. Our results indicate that high species diversity and occurrence of larger tree species are more important in carbon storage in lowland forest than at higher elevations. These findings are useful for management and land use planning of the forests in the Rumpi Hills Forest Reserve.

Genetic variations analysis of taif’s grapevine plants using three different types of gene –targeted molecular markers

The grapevine (Vitis vinifera L.) is a valuable commercial fruit crop in Taif Province, Saudi Arabia. Three different molecular markers, start codon targeted (SCoT), conserved DNA-derived polymorphism (CDDP) and inter-simple sequence repeats (ISSR), were used. The aim of this analysis was to examine the genetic relationships between 29 individual grape samples collected from three different locations in the Taif governorate. Firstly, all individual samples were confirmed to be Vitis vinifera L. by sequencing the chloroplast barcoding gene rbcL. Six primers of each molecular marker were used and successfully ampli?ed 74, 70 and 101 loci for ISSR, SCot and CDDP markers, correspondingly, of which all were polymorphic. The acquired average polymorphism information content was for ISSR, 0.16; for SCoT, 0.48; and for CDDP, 0.33, while average band informativeness was: ISSR, 12.2; SCoT, 34.1; and CDDP, 33.8. The results indicated that all used techniques were effectual for assessing the genetic diversity. The cluster partitions in the neighbour-joining dendrogram based on ISSR, SCoT and CDDP markers were semi-similar and grouped all individuals into two major groups. However, the dendrogram generated based on SCoT and CDDP can separate sample R12 into a third major group. Thus, these results indicate that SCoT and CDDP markers could be utilized as a consistent technique for the evaluation of genetic diversity and correlations among grapevine species, and DNA barcoding is necessary for authentication

DNA fingerprinting of Pakistani maize hybrids and parental lines using simple sequence repeat markers

Maize is important cereal crop which is used a major source of dietary ingredients. Due to implementation of Plant Breeders Rights, plant variety protection is absolute necessity. Plant variety protection using morphological markers is not a reliable source due to heavy influence of environmental factors. However, DNA fingerprinting using molecular markers is reliable technique as these are unaffected by environment. Present study was carried out for DNA fingerprinting of 08 maize genotypes comprising of 03 hybrids and 05 parental lines using 209 Simple Sequence Repeat markers. Sixteen SSR markers were not amplified, 19 were found monomorphic and 174 were polymorphic. A sum of 1015 alleles was amplified and 783 were found polymorphic. Maximum number of alleles (21) was recorded for umc1676, maximum number of polymorphic alleles (16) were recorded for p-Phi008. Polymorphic Information Content values ranged from 0.0 (umc1179) to 0.94 (umc1676) with an average 0.67. Jaccard’s similarity coefficient was used to construct a dendrogram based on unweighted pair group method with arithmetic mean and SAHN clustering. Maize hybrids and parental lines were classified to 03 clusters i.e. Group I, II and III on 96% similarity coefficient. DNA fingerprints were also developed for identification of maize hybrids as well as parental lines which will be useful for variety protection in future.

Genetic diversity and population structure of Populus yunnanensis revealed by SSR markers

Populus yunnanensis, a native poplar in southwest China, is a potential candidate to improve the quality of poplars due to its high growth rate, wide adaptability, and strong disease-resistant ability. However, the genetic structure of P. yunnanensis has not been determined. To illustrate the genetic diversity and population structure of P. yunnanensis, 6 SSR markers, amplified from 208 specimens of 7 populations, were used in this study. In total, 35 alleles with a mean of 6 were acquired, and the genetic diversity was at a moderate level. Populations from Qujing (QJ) and Dali (DL) showed abundant genetic diversities, whereas the population from Lijiang (LJ) had low genetic diversities due to a relatively recent population bottleneck. Both F-statistics and AMOVA results supported that the main genetic variation was attributed to individual differences within populations, and a high frequency gene flow (Nm = 5.560) occurred among populations. There was an overall increasing trend of genetic differences within populations from north to south and from east to west. Based on UPGMA, PCoA, and Bayesian analyses, populations from LJ, Liangshan (LS), QJ, and Zhaotong (ZT) were closely related to each other. A high barrier was found between the Kunming (KM) population and the Chuxiong (CX) population, and there was no correlated relationship (R = -0.159, P = 0.175) for the genetic and geographic distances between these two populations. We concluded that human activity was the decisive factor for shaping the present population distribution. Many potential resource types disappear at a fast rate, and the germplasm protection and scientific plan is imperative for breeding Populus and its genetic improvement.

Authentication of indigenously developed chilli (Capsicum annuum L.) hybrids through ISSR markers

Hybrid technology promises higher yields. For Capsicum annuum L., hybrid production is preferred because the vigorous yield uniformity, tolerance against biotic and abiotic stresses and other excellent horticultural traits. From the breeder’s perspective, development of hybrids permits better control of intellectual property rights including control and protection of parental lines. Nowadays elite chilli hybrids have become popular due to their best performance. At present indigenously developed 10 elite chilli hybrids (Hybrid-1 to Hybrid-10) along with their 6 elite parents/inbred lines were used for molecular study to authenticate the F₁ progeny. The DNA based hybrid purity testing was carried out by using 16 inter simple sequence repeat polymerase chain reaction (ISSR-PCR) markers. Out of 16;8 ISSR primers, which included six di-and two tri-nucleotide primers amplified clear and polymorphic bands in 1-10 hybrids with their parents. The number of amplicons per primer ranged from 4 (CA1, CA2) to 16 (CA9) with an average 9.125 amplicons per primers. The average numbers of polymorphic bands per primer were 2.12. F₁ purity was verified by the presence of parental specific band in each hybrid. The number of polymorphic bands ranged (2 to 4) but CA1, CA2, CA3 showed no polymorphic and parent specific bands. ISSR markers are beneficial and efficient for assessing the genetic purity of F₁ hybrids and provide better opportunity for selection of superior genotypes for breeding purposes. This is the first report on the use of ISSR markers which provides the basis for authentication and identification of each of the progenitors of F₁ hybrids of Capsicum annuum Land could be cited as ready reference for hybrid development and authentication in chillies.

Identification and mapping of an early leaf senescence trait, es2 mutant, in rice

Leaf senescence is the final stage of leaf development. Early senescence has negative impacts on crop productivity, especially in rice. In this study, early leaf senescence on chromosome 2 mutant, designated as es2, was generated by ethyl methanesulfonate (EMS) mutagenesis. Senescence symptom in es2 appeared at the late tillering stage, and was coincidence with elevated level of cell death, sugar content, and facilitated by senescence-associated genes (SAGs) transcription. Further, oxidative stress such as hydrogen peroxide (H₂O₂), oxidative stress byproducts such as malondialdehyde (MDA), and reactive oxygen species (ROS) contents were elevated in es2 while soluble protein content was decreased. Chloroplast ultrastructure of es2 was filled with larger in size of starch granule and higher in number of osmophilic plastoglobuli, along with looser thylakoid symptom. At the heading stage, es2 exhibited sharply decreasing of net photosynthetic rate (NPR) beginning from 14-28 days after heading. Consistently, es2 photosynthetic rate was dramatically lower than wild type (WT) in flag leaf, the second leaf from top, and the third leaf from top. Using map-based cloning technique, we identified that the target gene was anchored between RM12538 and RM12729 on the short arm of chromosome 2. Finally, this research provides a novel early leaf senescence mutant characterization in rice

Production and characterization of polyhydroxyalkanoates (PHAS) produced from bacillus cereus MUL-A isolated from biogas digester

Polyhydroxyalkanoic acids (PHA) are biodegradable polymers synthesized by microorganisms which can serve as alternative to conventional petrochemical based plastics. In the present study, twenty one bacterial isolates from one hundred & twenty six samples taken from anaerobic digester were screened for the PHA accumulation ability using Sudan Black B dye and further subjected to submerged fermentation to estimate the PHA production by maximum PHAs yielding strain. By 16S rRNA gene sequencing, the maximum PHAs yielding strain was identified as Bacillus cereus MUL-A. Effect of different physicochemical parameters such as temperature, pH, incubation time and composition of the modified PHA production media (PPMG) were studied on the polyhydroxyalkanoates (PHAs) yield. After 72 hours of submerged fermentation, a significantly high yield of PHAs i.e. 64.3% w/w were produced by the Bacillus cereus MUL-A strain by using PPMG medium having glucose (10 g/L) as carbon source and peptone (2 g/L) as nitrogen source at 35 ºC, pH 7.0. Provision of agricultural residues i.e. crude molasses and acid treated molasses as carbon source (6% v/v) & peptone (2 g/L) as nitrogen source in the PPMG medium has resulted in 36.9% and 44.6% biosynthesis of PHA content, respectively. Characterization of the purified PHA by Fourier transform infrared (FTIR) spectroscopy determined its purity and major functional groups. 

Biosynthesis of L-lysine by Bacillus megaterium through submerged fermentation

L-lysine is an important and essential amino acid required in a great quantity for supplementation in a number of food and feed items. The present work aimed at the biosynthesis of Lysine by B. megaterium IIB187 through shake flask fermentation. Fifteen different fermentation media were studied in present work for enhancing the production of Lysine. From the fifteen fermentation media, FM-13 medium consisting of ammonium sulphate, glucose, potassium hydrogen phosphate, dipotassium phosphate, thiamine, casamino acid, manganese chloride and biotin was found to be the best medium for maximum lysine production i,e., 0.51g/L. By optimizing physical parameters including incubation temperature (30°C), incubation time (72 hrs) and initial pH of medium (7.0), Bacillus megaterium IIB187 produced 0.59 g/L Lysine in fermentation medium FM-13. Further screening of carbon and nitrogen sources and optimizations of nutritional parameters were also carried out. Glucose and ammonium sulphate were found as the best carbon and nitrogen sources, respectively. Maximum production of lysine i.e., 0.69g/L was found in the presence of 7% glucose, while 2.5% ammonium sulphate resulted in the highest amount of lysine production. Maximum of 1.2 g/L Lysine was obtained after fermentation under the optimized conditions

Phytotoxic, insecticidal and cytotoxic activities of Ziziphus mauritiana var. Spontanea Edgew. and Oenothera biennis L.

The present study investigates phytotoxic, insecticidal and cytotoxic activities of samples extracted from Ziziphus mauritiana var. spontanea Edgew. and Oenothera biennis L. Good phytotoxic activity was measured by the ethanolic extract of Z. mauritiana var. spontanea and ethyl acetate extract of O. biennis against Lemna minor. Ethyl acetate samples of Z. mauritiana var. spontanea and O. biennis was very active against Rhizopertha dominica and Sitophilus oryzae respectively. Maximum activity against brine shrimps was noted for the ethanolic samples of Z. mauritiana var. spontanea and O. biennis ethyl acetate extract. Phytochemical screening of different solvent extracted samples of Z. mauritiana var. spontanea and O. biennis confirmed the presence of alkaloids, flavonoids, glycosides, saponin and tannins

Morphological and biochemical characterization of rhizobacteria associated with peach plant and evaluation of these rhizobacteria against its fungal pathogens

Rhizospheric bacteria directly or indirectly affect plant growth. Management of plant diseases through biocontrol agents is one of the best approach that mayreduce the use of synthetic chemical based formulations. In this study, antagonistic activities of Bacillus subtiliswas evaluated In vitro against: Monilinia fructicola, Taphrina deformans and Alternaria alternate which cause Brown rot, Peach leaf curl and Alternaria rot. In dual culture technique, microbial antagonists inhibited the spore germination and mycelial growth of Moniliniafructicola and Alternaria alternata. Pathogenicity test for Taphrina deformance was also performed on leavesof Peach seedlings while pathogenicity of Monilinia fructicola and Alternaria alternata were done on Peach fruit being fruit rotting fungi. Out of 16 isolates,3 isolates B.subtilis viz., Rh3, Rh7 and Rh12 showed strongest activity against Monilinia fructicola, having 12mm, 12mm and9mm zone of inhibition for Taphrina deformans; 9mm, 9mm and 7mm and for Alternaria alternata and 8mm, 7.5 and 6mm zone of inhibition against. B. subtllis showed better results against Monilinia frecticola as compared to other pathogens Taphrinadeformans and Alternaria alternata. Many researchers are working on the biological control of fungal plant pathogens using antagonistic rhizo bacterial strains belonging to the genus Bacillus. The results of this study identify B. subtilis as encouraging biological control agents for further testing against Brown rot, Alternaria rot in fruit and peach leaf curl disease in peach leaves

Assessment of deoxynivalenol (DON) mycotoxin in corn and wheat grain consumed in central Punjab, Pakistan

Deoxynivalenol (DON) belongs to trichothecene mycotoxins having acute and chronic health hazards to human beings. The purpose of the current study was to assess DON concentration in corn and wheat samples (n = 200) collected from central Punjab, Faisalabad. Occurrence of DON in samples was analyzed by HPLC using UV-Vis detector in isocratic mode. Results indicated that 63% of corn samples were effected with DON residue. Out of these contaminated samples, 66% had higher residue level (1250 µg kg^-1) than the maximum limit as permissible by the European Commission Law (ECL) for DON. Among contaminated samples, 49.2% were found highly contaminated with DON with value of more than 1401 µg/kg. In the case of wheat grains, contamination of the DON was noticed in 56% samples with an average residue value of 1352 µg/kg. DON contamination level ranged from 1442-1524. The level of DON was compared among urban, rural and semi-urban areas and was detected to be highest in rural areas in both corn (1512 µg/kg) and wheat (1585 µg/kg) grains. The high concentration of trichothecene (DON) levels in corn and wheat grains may pose substantial health problems for the population of central Punjab, Pakistan and need urgent attention to address the issue of mycotoxins in staple food

Effect of different levels of molybdenum and rhizobium phaseoli in rice-mung bean cropping system

Ignorance of trace elements (iron, cobalt and molybdenum etc.) may result in reduced crop yield. Leguminous crops are very sensitive towards molybdenum (Mo) deficiency, but excessive Mo may also impair the growth, decrease biomass, seed yield and quality of produce. Many scientists had documented information regarding sole inoculation of combined Rhizobium and effects of Mo, however, limited information is available on combined use of Mo and Rhizobium inoculation on mung bean (Vigna radiata L.) productivity. Therefore, current study was conducted for assessing the effects of Rhizobium with Mo supply on yield attributes and N₂-fixation in V. radiata. There were 2 levels of Rhizobium inoculations (with and without rhizobia) and 5 levels of Mo (0, 3, 4, 5 and 6 g kg^-1 seed) applied during 2015 and 2016 cropping seasons for cultivation of V. radiata. Results showed that at maturity plant height, pod bearing branches/plant, nodules and pods/plant, seeds/pod, pod length, 1000-grain weigh, seed yield and protein were significantly increased 25.4, 80.7, 109.3, 22.3, 49.4, 43.3, 23.6, 96.9 and 18.9 % respectively, where Mo (4 g/kg) + R. phaseoli was applied as compared to control. In conclusion, combined use of Mo and Rhizobium have potential to enhance productivity and quality of mung bean

Impact of chemical priming on root infecting fungi, photosynthesis and yield components of cowpea and mung bean

The aim of the present research is to provide information regarding the effect of signal molecule (H₂O₂) and a growth hormone (SA) on growth of cowpea (Vigna unguiculata [L.] Walp) and mung bean (Vigna radiata L.) plants under lab and in field conditions. Three different concentrations of SA and H₂O₂ (0.5, 1 and 2%) were prepared and subsequently seeds were primed with the above concentrations for 5 mins. and placed on Petri plates against root infecting fungi. Results revealed that the seeds primed with 0.5% showed germination while 2% concentration inhibited the growth of Rhizoctonia solani Kuhn, Fusarium oxysporum Schlechtendahl and Macrophomina phaseolina (Tassi) Goid by displaying zone of inhibition. In field, shoot length and weight, root length and weight, nodules, number, length and weight of pods were increased when cowpea and mung seeds primed with H₂O₂ at 0.5% concentration. However, root infecting fungi like M. phaseolina, R. solani and Fusarium species was also decreased by application of H₂O₂ at 0.5% as compared to other treatments. Increased Fv/Fm was recorded in cowpea and mung bean seeds primed with water while increased performance index was obtained in seeds primed with H₂O₂ resulting in improved chlorophyll performance. However, seeds primed with water showed decrease in performance index. 

Evaluation of fungicidal potential of Ocimum sanctum L. and Nicotiana tabacum L. against Aspergillus flavus and Aspergillus niger

The current study aimed to assess the antifungal potential of two medicinal plants (Nicotiana tabacum L. and Ocimum sanctum L. belonging to the Solanaceae and Lamiaceae families respectively against Aspergillus niger van Tieghem and Aspergillus flavus Link. Both plants were selected on the basis of their ethnobotanical uses. Dried test plants were dipped in methanol as the extraction solvent, and after getting filtrated by means of maceration procedure, their crude extracts were prepared. Methanolic crude extracts were then subjected to bioassay-guided fractionation to make various solvent fractions viz. n-hexane, dichloromethane, ethyl acetate and n-butanol. Phytochemical analysis was also carried out afterwards to confirm the absence or presence of secondary metabolites in test plants.  Two concentrations i.e 0.1% and 0.3% of each fraction of O. sanctum and N. tabacum were prepared to conduct the antifungal assay. Results of antifungal test revealed that n-butanol fraction of N. tabacum had more potential in controlling the growth of A. flavus at 0.1 % in comparison to A. niger.  On the other hand, O. sanctum proved to be efficient in the retardation of A. niger with a fraction of n-hexane (100%) at 0.3% concentration. Hence it is depicted by results that both of tested plants have vast potential to be used as antifungal agents

Morphological and molecular charactererization of macro fungi from district Astore, Gilgit-Baltistan, Pakistan

Present study is an attempt to estimate the genetic diversity of important macro fungi from district Astore using DNA based markers. The Province Gilgit-Baltistab represents a floristically rich area characterized by the moist and dry temperate forest region with rich macro fungal diversity. Duringthe field visits from March to August selected different localities of Astore were visited and collection was doneand subsequently identified macro fungal species on the basis of morphological and molecular characteristics viz., Bjerkandra adusta, Fomes fomentarius, Rigidoporus ulmarius and Tremetes versicolor were reported first time from Pakistan. Another ten species viz., Lepiota sistrata, Krombholziella scabra, Suillus leutus, Inocybe agardhii, Cyathus olla, Phallus impedicus, Schizophylum commune, Coprinus domesticus, Morchella esculenta and M. conica were reported first time from the study area. The fourteen fungal species were attended by eleven Randomly Amplified Polymorphic (RAPD) DNA primers. Bivariate data was used to estimate genetic diversity in different fourteen fungal accessions using unpaired group of arithmetic mean (UPGMA) procedure. High level genetic diversity ranging from 40% to 80% was observed in the fungal species. Samples of accessions were also grouped in to 7 clusters using dendrogram analysis

Isolation, characterization and evolution of wild virulent strains of Agrobacterium for their potential transformation through use of potato discs

The present study was aimed to investigate the Crown galls of the trees and plants caused by Agrobacterium. For the purpose, the Crown galls were collected from Botanical and Horticultural Gardens of Sindh Agriculture University, Tandojam, Pakistan and examined for Agrobacterium species. In all 90 Crown galls were examined for Agrobacterium species. The Crown galls extracts were obtained   and streaked on PYGA (Peptone, Yeast extract, Glycerol, Agar) and Luria–Bertani (LB) media supplemented with rifampicin (30 µl L^-1) antibiotic to inhibit the growth of other bacterial organisms and the plates were incubated at 28°C for 48 hours.  Only thirty (33.333%) wild isolates of the Agrobacterium tumefaciens were isolated from Crown galls. However, nineteen (19) isolates out of 30 were confirmed as Agrobacterium tumefaciens. Among these 19 isolates, At224 was found to be the most virulent strain which showed  80% transformation efficiency (TE) while other three isolates i-e At213-TE: 70%; At222-TE: 70% and At230-TE:70% were  induced solid green cell masses/tumors/ galls on the potato discs vigorously. Of the tested isolates, the isolate At224 (Mangifera indica) was the most virulent strain that caused 80% transformation as compared to other isolates.  Furthermore, when comparison was  made among isolates recovered from Crown galls and that of controlled for phenotypical  characteristics,  the majority  of isolates showed similar characteristics as demonstrated in the controlled (At 2441- EHA101). Moreover, Ti plasmid was found visible in by using 0.8% in 50 ml of TAE buffer solution. Thus Ti plasmid that helped in for the characterization of wild Agrobacterium by molecular system

Isolation and identification of natural herbicidal compound from a plant pathogenic fungus, Drechslera biseptata

Weeds incur heavy losses in crop production. Use of agrochemicals is wide spread in weed management all over the world but all of these agrochemicals are associated with numerous undesired side effects. In recent years, there is emerging trend of exploring natural herbicides from plants and microbes. In this study, phytotoxic metabolites produced by phytopathogenic fungus Drechslera biseptata (Sacc. & Roum.) Richardson & Fraser were investigated for their herbicidal activity against Rumex dentatus L., a cosmopolitan noxious weed that causes enormous yield losses in different wheat varieties. For this aim, extracts (Ethanolic extract and partitioned ethanolic extracts), chromatographic fractions and main secondary metabolite, obtained from culture of D. biseptata were tested on R. dentatus. A phytotoxic pure compound was identified as di-(2-ethyl-hexyl)-phthalate (DEHP), by spectroscopic techniques [Mass Spectrometry (MS) and Nuclear Magnetic Resonance Spectrometry (NMR)]. In leaf disk assay, DEHP at 0.5 μg μL^-1 produced necrosis on weed but not on wheat leaves. On the other hand, synthetic herbicidal compound, 2,4-dichlorophenoxyacetic acid, used as positive control, produced necrotic spots at leaf discs of R. dentatus at concentration of 0.25 μg μL^-1. The present investigation suggests the use of DEHP as natural herbicidal compound.

Effect of Lugus sp. feeding and a Saponin application on volatiles released by quinoa

In consequence of insect feeding and saponin application tested quinoa plants released large amounts of volatile organic compounds (VOCs) to compare to control. For cv. ‘Faro’ these were the following components: (Z)-3-hexenal – (Z)-3-HAL, (E)-2-hexenal – (E)-2-HAL, (Z)-3-hexen-1-ol – (Z)-3-HOL, (E)-2-hexen-1-ol – (E)-2-HOL, (Z)-3-hexen-1-yl acetate – (Z)-3-HAC, 1-hexyl acetate – 1-HAC, (Z)-ocimene - (Z)-OCI, benzyl acetate - BAC, methyl salicylate - MAT, β-caryophyllene – β-CAR, (E)-β–farnesene – (E)-β-FAR. Cv. ‘Puno’ released 7 VOCs and these were: (Z)-3-HAL, (Z)-3-HOL, (Z)-3-HAC, (Z)-OCI, MAT, β-CAR, and (E)– β-FAR. The fragrance bouquet of the third of variety tested (cv. ‘Titicaca’) consisted of 6 components: (Z)-3-HAL, (E)-2-HAL, (E)-2-HOL, (Z)-3-HAC, (Z)-OCI, and β-CAR. In general, much larger VOCs emission was observed in plants after insect feeding compared to saponin applications and especially control.

Antioxidant and chemical constituents of ethyl acetate extract of Tamarix aphylla leaveas in Saudi Arabia

The purpose of this study was to determine the phytochemical analysis, antioxidant activity and chemical components of ethayl acetate extract of T. aphylla from Saudi cultivar. The objective of this study was to characterize the extract for its phytochemical composition and antioxidant activity. Phytochemical analysis of crude extracts for T. aphylla detected the presence of alkaloids, flavonoids, tannins, and saponins, whereas, both steroids and triterpenoids were absent. The maximum total phenol content   was 39.3 mg gallic acid / g dry extract. The antioxidant activity was evaluated by DPPH assay; concentration of T. aphylla 1,5,10,15,20 and 25 mg/ml corresponed to scavenging activities of ~22.1%, 31.4%, 39.2%,53.5,60.0 and 66.3%, respectively. While for ascorbic acid (Standard), the scavenging activities were 33.1,46.2,51.6,58.2,67.3 and 72.2% at the same concentrations. IC50 value of T. aphylla was 14.0 mg/ml whereas it was 9.0 mg/ml for ascorbic acid. Addition GC-MS chromatogram of T. aphylla ethyl acetate extract were presented twenty-three constituents.