Salicylic acid seed priming modulates some biochemical parameters to improve germination and seedling growth of salt stressed wheat (Triticum aestivum L.)

Salicylic acid (SA) is a plant signaling molecule, which regulates various metabolic processes and involves in eliciting specific responses against abiotic/biotic stresses. Present study investigated the effect of SA on seed germination and seedling growth of salt stressed wheat. Wheat seeds were primed with water and two concentrations of SA (0.5 and 1.0 mM) for 12 h. For In-vitro experiment, seeds were soaked in 0, 50 and 100 mM NaCl solutions and seed germination and seedling growth parameters were studied. Primed seeds (both 0.5 and 1.0 mM SA) significantly improved seed germination, rate of germination, total chlorophyll, soluble sugars, proteins and phenolic content, as compared to non-primed and hydro-primed controls. For greenhouse experiment, hydro-primed (control) and SA primed (0.5 and 1.0 mM) seeds were grown in plastic pots and irrigated with 0 and 100 mM NaCl for 4 weeks. Plants emerged from SA primed seeds showed better response to salinity in which higher contents of photosynthetic pigments, soluble sugars, proteins and phenols contributed to enhanced growth and biomass production, as compare to control plants. Seed priming with 1.0 mM SA was found most effective to protect plants from damaging effects of salinity as compare to hydro-priming and 0.5 mM SA priming. Therefore, it is suggested that the priming of seeds with 1.0 mM SA can be adopted as a strategy to enhance wheat growth especially in salt affected soils

Low iron level improves salt tolerance by changing the redox regulatory mechanisms in Arabidopsis thaliana

Soil salinization is a critical restrictive causal factor for plant growth. The soluble salts could lead to low crop growth and production; thus, it is very crucial to improve plant salt tolerance. Iron (Fe) is involved in plant growth and development, and many other metabolic pathways. Yet, little research on the relationship between iron content and salt tolerance has been done in previous works. By using a series of Fe gradient treatments, this study explored the role of Fe in Arabidopsis thaliana tolerance to salt stress. Germination tryout results exposed greater salt tolerance at lower Fe treatments than at higher Fe treatments. Some indicators, such as iron leakage, levels of sodium, potassium and reactive oxygen species of roots also indicated increased tolerance to salinity in case of low Fe treatments. Reduced glutathione levels of plants were caused by salt stress and it designated further increased damage of an oxidation state. Nevertheless, high Fe content tended to cause more damages to the redox system than low Fe content. In conclusion, Fe content had a significant function in resistance to salinity by plants. The main explanation of the resistance to salt by plants may be the Fe’s ability to bring about changes in the redox potential.

Influence of boron nutrition on physiological parameters and productivity of cotton (Gossypium hirsutum L.) crop

The productivity of arable crops is greatly impacted by imbalanced nutrient management. The deficiency of one or more mineral nutrients can cause substantial reduction in crop yields. Of the micronutrients, the deficiency of boron affects the yield potential of cotton to the greatest extent. This study was carried out to quantify the boron nutritional requirement of cotton. The treatments included three boron levels (0.0, 0.75 and 1.50 kg B ha^-1) and two application regimes (soil and soil plus foliar). Foliar application was done at 30, 60 and 90 days after sowing during peak growth stages. The results revealed that application of 1.50 kg B ha^-1 along with foliar sprays increases crop growth rate (CGR) and net assimilation rate (NAR) by 15% and 31% respectively. While, the membrane leakage was reduced by 35% by addition of 1.50 kg B ha^-1, chlorophyll a and b contents improved by 2% and 5% through combined application of boron via soil and foliar spray. The water-use-efficiency was enhanced by 35% by application of B-fertilizer through soil as well foliar spray. Gas exchange parameters, i.e.net photosynthetic rate, transpiration rate and stomatal conductance increased by 66%, 47% and 62% respectively after application of B-fertilizer and there was a significant increase in number of bolls per plant, boll weight and an ultimate improvement in final seed cotton yield of 16%.

Exogenous sodium nitroprusside increases antioxidative potential and grain yield of bread wheat exposed to cadmium

The cadmium accumulation declines the crop productivity by disturbing the metabolism of plant. Thus, it is very essential to know the process of Cd effects through Cd-induced physio-biochemical determinations as well as its accretion, carrying and the associations with development, mineral nutrients and the antioxidant systems. The experiments were conducted under different Cd (control, 0.3, 0.6, 0.9 and 1.2 mM) regimes without or with an exogenous NO donor, sodium nitroprusside (0.15 and 0.30 mM SNP) on four cultivars of wheat (Punjab-2011, AARI-2011, Millat-2011 and Sehar-2006). The exogenous SNP was effective in improving growth of Cd-stressed wheat plants. Cd stress caused a noticeable repression in flavaniods, total phenolics, soluble proteins, and grain yield components while increased total free ascorbic acid (AsA), proline, glycinebetain (GB), glucose and sucrose, malondialdehyde (MDA), hydrogen peroxide (H₂O₂) and the activity of enzymes including catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD) and peroxidase (POD) irrespective of wheat cultivars. More effective of both SNP levels was 0.30 mM. Of wheat cultivars, Punjab-2011 and AARI-2011 performed better than Millat-2011 and Sehar-2006. The exogenous NO was effective in improving total flavaniods, total phenolics, soluble proteins, and grain yield components under Cd stress. Furthermore, NO reversed the effects of Cd on reducing and non-reducing sugars, proline, total free amino acids, H₂O_2, MDA and enzyme activity of APX, CAT and POD irrespective of wheat cultivars. Overall, the results elaborated that exogenously applied NO reduced the Cd toxicity in wheat

Changes based on oxidative stress in metolachlor and atrazine treated maize seedlings

The present study investigated biochemical effects of Atrazine (0, 200μM , 500 μM and 1000 μM) and Metolachlor (0, 100μM , 500 μM and 1000 μM) concentrations applied to 15-day-old seedlings of three maize varieties (Zea mays L., cv. Saccharata, cv. Danona, and cv. Advanta 2898) for 48 hr. Hydroponic environment was preferred for all treatments for the seedlings. Compared to their controls, GSH/GSSG ratio was decreased, SOD activity was increased, and CAT activity was also decreased/decreased in root/leaf of Atrazine treated maize seedlings. While % ratios of fatty acids in leaf was increased for palmitic acid and palmitoleic acid in cv. Saccharata and advanta 2898, but was decreased in cv. Danona. While the rate of linoleic acid was increased in leaves in other two ratios but decreased only in cv. Saccharata; linoleic acid was increased only in cv. Saccharata and decreased in others. Compared to their controls, in root/leaf of maize seedlings treated with Metolachlor; GSH/GSSG ratio decreased/increased, SOD activity decreased/increased, and CAT activity decreased/decreased. While % ratios of fatty acids in leaf showed an exceptional increase and increase for linolenic acid, palmitic acid, and linoleic acid; palmitoleic acid and stearic acid decreased and palmitic acid decreased only in cv. Advanta 2898. Generally, the inhibitive effect of the herbicides Atrazine and Metolachlor elevated in parallel to increased dose (1000 μM).However, Atrazine displayed a more oxidative damagesthan Metolachlor on three maize varieties

Toxicological effect of CuO nanoparticles to Brassica nigra L. seedlings: a comparative in vivo and in vitro response

Metallic nanoparticles including CuO are considered toxic when released in the environment. However, the toxicity is concentration dependent. In present investigation, we report toxicological consequences of CuO nanoparticles under In vivo and In vitro conditions to Brassica nigra L (a model legume plant). To investigate LD50 (lethal dose), the seeds were germinated in presence of CuO NPs (1-1000 mg/L for In vitro and 10-200 mg/kg soil for In vivo condition). In both, In vitro and In vivo cases no or positive effect was observed on plant length, fresh and dry weight up to threshold concentration. Above that negative effect was observed on all physiological parameters. Under In vitro conditions Total phenolics and flavonoids (TPC and TFC), total antioxidative potential (TAC), total reducing power (TRP) and free radical scavenging activity fluctuated in Brassica plantlets by change in NPs concentration. While under In vivo application in Brassica plantlets TPC, TAC and TFC increased up to some concentration and then decreased while increasing the NPs concentration. Minor significant change was observed in TRP and DPPH based free radical scavenging activity continuously increased by increasing NPs concentration. HPLC analysis was performed for determination of rutin, gallic acid and caeffic acid in plants. All the three antioxidative molecules were found at varying concentration when plants were grown in presence of CuO NPs. The results conclude that under In vivo and In vitro condition NPs have different toxicity to plants which results in differential plant response to scavenge the free radicals and oxidative stress

Exogenous application of salicylic acid improves physiological processes of maize (Zea mays L.) hybrids under limited water conditions

Drought is one of the most important abiotic factors acting as a bar in the progress of agriculture around the world. Like other crops, cereals also have to endure the impact of limited water availability. A pot experiment was conducted to check the effects of exogenous application of salicylic acid (SA) on physiological processes of spring maize (DK-6525 and NK- 8711). In this experiment, seed priming, foliar of SA and their combined effects of SA @ 100 mg L^-1 were checked at vegetative as well as reproductive growth stages of maize. In this experiment control was no priming and no spray. Then hydro-priming and distilled water spray at vegetative as well as reproductive growth stages was applied to have a better comparison with SA application. Crop was raised till its maturity. Results of physio-chemical attributes showed that foliar application of SA at the vegetative growth stage of maize improved dry matter production per plant by 26% under moisture stress conditions along with the water relations and gas exchange parameters to a significant extent

Gold nanoparticles biosynthesis using Zingiber officinale and their impact on growth and chemical composition of lentil (Lens culinaris Medic.)

The synthesis of gold nanoparticles (AuNPs) using Zingiber officinale has been reported in the study, and the impact of the different concentrations (ppm) of gold nanoparticles is investigated. Five different concentrations (0, 10, 25, 50 and 100 ppm) of gold nanoparticles were applied to examine physiological (including seeds germination, plant height, leaf  number and biomass production) and biochemical parameters (including total soluble sugars, total soluble phenols, total chlorophyll , carotenoids, total soluble amino acids and protein contents) of the seedlings of Lens culinaris as a model of Legumes crop. GNPs were synthesized and characterized through Uv-visible spectra, transmission electron microscopy, XRD and FTIR. Generally, all growth and biochemical parameters were increased as a result of treatment with gold nanoparticles by using low concentrations only at 5ppm and 10ppm, while at high concentrations the effect is reversed.

Effect of naphthaleneacetic acid on root and plant growth and yield of ten irrigated wheat genotypes

Plant growth regulators (PGRs), such as 1-naphthaleneacetic acid (NAA), gibberellins, cytokinins, abscisic acid, and ethylene have become commercialized in some countries to increase the productivity of field crops and to fortify the value of horticultural crops. However, very limited research has been conducted in Bangladesh on root growth, plant biomass and yield of wheat (Triticum aestivum L.) using NAA. In this context, an experiment was conducted over two consecutive seasons, from November to April, in the research field of the Wheat Research Center (WRC) (under Old Himalayan Piedmont Plain), Dinajpur-Bangladesh. Treatments consisted of the application of 25 mg/l NAA in five temporal regimes: 1) NAA applied at 20, 35 and 50 days after emergence (DAS); 2) NAA applied at 20 and 35 DAS; 3) NAA applied at 20 and 50 DAS; 4) NAA applied at 35 and 50 DAS; 5) a control (without NAA). Treatments were applied to 10 irrigated spring wheat genotypes i.e., ‘Kanchan’, ‘Protiva’, ‘Surov’, ‘Gourov’, ‘BAW 944’, ‘BAW 953’, ‘BAW 994’, ‘Akbar’, ‘Agrhani’ and ‘Sonalika’, and arranged in a split-plot design, namely as five NAA treatments as the main plots and 10 wheat genotypes as the sub-plots. In both seasons, data on root fresh and dry weight, root length, total plant dry biomass (TDM), grain yield (GY) and yield attributes of wheat were significantly (p≤0.05) influenced by the NAA application regime and genotype. However, maximum root fresh and dry weight and longest roots were recorded in treatment 2 for ‘Gourav’. Maximum TDM was recorded at 40 and 50 DAS for ‘BAW 944’ in treatment 3. Significantly similar and maximum TDM at 60 DAS was found for ‘Kanchan’ and ‘Sourav’ in treatment 1 and at 70 DAS for ‘Sourav’ in treatment 2. ‘BAW 994’, ‘BAW 953’ and ‘Agrahani’ produced significantly similar and maximum number of spikelets spike^-1 in treatment 2. ‘BAW 944’ and ‘BAW 953’ showed significantly similar 1000-grain weight in treatment 3 while smallest grain size was obtained in ‘BAW 953’ in the control treatment. ‘BAW 953’ produced highest GY in treatment 1, and was statistically similar to ‘BAW 994’ and ‘Protiva’ after the application of treatments 2 and 4. Therefore, the application of NAA at 20, 35 and 50 DAS in all genotypes was more effective (i.e., better root growth and yield) than the control plot. Among the 10 tested genotypes, ‘BAW 953’ and ‘BAW 994’ responded most to NAA.

Analysis on phenotype, catalpol accumulation and methylation of Rehmannia glutinosa

Rehmannia glutinosa is one of traditional Chinese herbal medicines, its phenotype, catalpol accumulation and genomic methylation were studied in this research. During the growth and development of Rehmannia glutinosa, leaf length, plant height and catalpol accumulation increased continuously along with the extension of growth stage, and reached peak in the later growth stage. 5-methylcytosine (5mC) content and methylation level in genome also increased along with the growth of Rehmannia glutinosa, and reached the highest value in the later growth stage, however genomic methylation in leaf and root was different at the same growth stage and was higher in leaf. As compared with that of Rehmannia glutinosa planted in Xinxiang, leaf length, plant height, catalpol accumulation and 5mC content in Wenxian were all higher at the same growth stage, full-methylation was main in genomic methylation of Rehmannia glutinosa planted in Wenxian, yet semi-methylation was main for genomic methylation of Rehmannia glutinosa plants in Xinxiang. Therefore, Wenxian maybe more suitable to plant Rehmannia glutinosa, and this research would help to explore the correlation between ecological environment and growth of Rehmannia glutinosa.

The identification of eighteen precursor miRNA clusters and their targets in barley (Hordeum vulgare L.)

MicroRNAs (miRNAs) are short, endogenous and non-protein coding RNAs that are 18-26 nucleotides (nt) in length. The miRNAs have been shown to play important regulatory roles in almost all plant processes, including responses to various stresses. These regulatory functions of the miRNAs are to negatively control the protein coding sequences at post-transcriptional level. The mature miRNAs (18-26 nt) are generated from long (50-550 nt) precursor miRNAs (pre-miRNAs). Mostly the pre-miRNAs have one mature miRNA sequence in the stem region, but few have been reported with more than one mature miRNAs. Such miRNAs are called pre-miRNA cluster. In current research, various computational tools were used for the identification and characterization of new conserved pre-miRNA clusters and their targets in barley (Hordeum vulgare L.). Consequently, a total 18 new pre-miRNA clusters were identified from 17 miRNAs families in barley from total 501,838 express sequence tags (ESTs). These miRNA families were: miR394, 396, 414, 473, 475, 482, 817, 1432, 2118, 2673, 5066, 5070, 5168, 5181, 5201, 5522 and 7757. The miR-5070 was identified as sense and anti-sense cluster and 81 protein targets were identified for pre-miRNA clusters. These protein targets were categorized as: hypothetical protein, metabolism protein, transcription factor, transporter protein, cell signaling protein, growth & development protein and structural proteins.  These newly identified pre-miRNA clusters and their 81 targets were reported here for the first time in barley. These results will be a good contribution to fine-tune the regulation of barley for better yields, agronomic traits and stress management

Genetic monitoring of introgressed alleles from Gossypium arboreum L. into G. hirsutum L. using SSR markers: a potential approach for bringing new alleles under cultivation

In the present investigation, a BC₄F₂ population was developed from a cross [(2 G. arboreum) G. hirsutum] for transferring resistance to cotton leaf curl disease (CLCuD) from G. arboreum into G. hirsutum. Both parent species were surveyed with 156 SSR markers, and 19 SSRs were found polymorphic amplifying 81 alleles. Out of these, 31 alleles were informative (nine derived from G. arboreum while 24 derived from G. hirsutum). Four high yielding BC₄F₂ selected plants were surveyed with these polymorphic SSRs. Two SSR markers (JESPR-156-closely linked with QTLs conferring resistance to CLCuD and MGHES-15-closely linked with genes involved in shaping plant architecture) showed introgression of alleles derived from G. arboreum into G. hirsutum (BC₄F₂). One novel allele (not derived from either of the parent species) was also amplified in one of the BC₄F₂ plants, possibly generated due to structural changes in cotton genome after polyploidization, or colchicine treatment/ovule culture. These genetic introgressions monitored through DNA markers from alien sources into cultivated gene pool can buffer the potential risks of diseases and the changing environment.

Genetic variability study of elite guar (Cyamopsis tetragonoloba L.) germplasm as revealed by SDS-page technique

Biochemical characterization of plant species through SDS-PAGE method plays a key role in seed storage protein based variations. Limited reports are available about the protein profiling of elite Cyamopsis tetragonoloba L. (Guar) germplasm. In present study we have characterized the seed storage protein profiles of elite accessions of guar. The 24 guar germplasm were characterized though standard SDS-PAGE protocol with minor modifications. These genotypes were analyzed with novel 2D and 3D methods to visualize diverged genotypes from the close angle. Significant variability was observed in protein profile of all tested genotypes. The polypeptide band sizes varied from 10-180kDa. Maximum (100%) polymorphic banding patterns were observed among genotypes. The genetic similarity values ranged from 20 to 100% among genotypes. The accessions 28952 and 31682 indicated the highest genetic similarity value (100%). While the lowest similarity value (20%) was recorded between accessions 31731 and 31764. All these genotypes were classified into 7 diverse groups and the last 3 were highly diverged as compared to others. The 2D and 3D protein structure models identified 3 unique accessions like 31764, 31731 and 31761. The resulted novel genotypes will be useful for further improvement of this important plant species

Integration of cytological and molecular analysis to confirm a hybridity in F1 Brassica progeny 

In Brassica, interspecific hybridization is a potential and useful method for transferring valuable traits between species of commercial interest. In the previous experiments successful interspecific hybrids were obtained through hybridization between chosen rapeseed cultivars (Brassica napus L.) and Brassica rapa genotypes for transferring clubroot resistance from wild species into cultivated background. In the presented research morphological, cytological and simple sequence repeats (SSR)-based molecular analyses were carried out to confirm the hybrid nature of the F₁ plants.  This paper evidences for a successful creation of twenty three F₁ interspecific hybrids where six out of eleven cross combinations were confirmed as fertile. The obtained results have shown that analyzed morphological characters of F₁ hybrids were intermediate as compared to those of both parental genotypes. Furthermore, in pollen mother cells (PMCs) of the F₁ hybrids abnormalities like univalent, lagging chromosomes and disorders in synchronization were observed in meiosis. Generally, the abnormalities in meiosis occurred in most of the tested genotypes with the mean frequency of 63.8%. Among tested SSR primers, Na10-A08 was found to reveal highly polymorphic bands in hybrids. As a result, 41.1% of the investigated plants were confirmed as true hybrids.

Integrated control of Jungle rice in hybrid maize through sorghum allelopathy

Sorghum allelopathy has long been utilized as a bio-control technique for unwanted flora in economic crops and circumvent undue dependency on chemical weed control. An experiment was conducted during kharif season of 2017 to examine the integration of sorghum water extract (SWE), sorghum mulch (SM) and half dose of post emergence herbicide mesotrione + atrazine (MA₅₀) for controlling jungle rice in hybrid maize (HC-8080). The treatments included; T₀: Check, T₁: Full dose (1250 ml ha^-1) of mesotrione + atrazine (MA₁₀₀), T₂: Half dose (625 ml ha^-1) of mesotrione + atrazine (MA₅₀), T₃: SWE @ 15 L ha^-1 + 625 ml ha^-1 (1/2 dose) of mesotrione + atrazine (MA₅₀), T₄: SM @ 8 t ha^-1 + 625 ml ha^-1 (1/2 dose) of mesotrione + atrazine (MA₅₀), T₅: SM @ 8 t ha^-1 + SWE @ 15 L ha^-1 and T₆: SM @ 8 t ha^-1 + SWE @ 15 L ha^-1 + 625 ml ha^-1 (1/2 dose) of mesotrione + atrazine (MA₅₀). The results of the study unveiled that combination of SWE + SM + MA₅₀ reduced the fresh weed biomass by 84.82% and dry weed biomass by 87.37% and increased all the agronomic parameters eventually registering maximum kernel yield (4.80 t ha^-1). Overall, the response of this treatment was similar as that of standard herbicide dose. Therefore it was concluded that standard dose of mesotrione + atrazine herbicide can be reduced to half with the integration of sorghum water extract and sorghum mulch which will ensure efficient and eco-friendly control of jungle rice

Interspecific hybrid compatibility of Huaren apricot with almond

Interspecific hybridization is an effective method of fruit tree breeding for new varieties. In order to understand interspecific hybridization compatibility, abortive period, and the development of hybrid fruit from crosses between Huaren apricot and almond, we conducted crossing experiments. The growth condition of the pollen tube was observed by fluorescence electron microscopy, and the abortion rate and developmental characteristics of hybrid fruit were analyzed in different stages. The results showed that the pollen of Huaren apricot and almond were able to germinate, and that the pollen tubes can enter into the embryo sac of the other species. After four weeks of cross pollination, the average fruit-setting rate of the interspecific hybrid was 7.06% using Huaren apricot as female parent, which was 24.39% of the intraspecific hybridization rate; mature fruit accounted for 17.54% of the young fruit. When almond was used as the female parent, the average fruit-setting rate of interspecific hybridization was 6.33%, which was 46.10% of the intraspecific hybridization, and the mature fruit accounted for 5.17% of the young fruit. However, the embryos were aborted after the fruit ripened. The fruit of interspecific hybrids with Huaren apricot as the female parent grew slower than that of the intraspecific hybrid. In addition, the fruit was smaller when mature and embryo development was normal in the former as compared with that in the latter. The fruit development after interspecific hybridization using almond as the female parent was consistent with that of the intraspecific hybrids. However, the embryonic development gradually stopped, and malformed and normal embryos could not be formed. There is a high potential for interspecific hybridization between Huaren apricot and almond. Particularly, using Huaren apricot as a female parent, a well-developed embryo can be obtained.

Genome-wide identification and characterization of TCP family genes associated with flower and fruit development in Fragaria vesca

TEOSINTE-BRANCHED1/CYCLOIDEA/PCF (TCP) protein family is a large transcriptional regulator family in plant, which are important in various plant processes including leaf development, flower symmetry, shoot branching, and senescence. In this study, phylogenetic relationship, chromosome location, conservative domain structure and expression profiles in flower and fruit development of the TCP TFs family in woodland strawberry (Fragaria vesca) was performed. In total, 18 TCP members were identified in F. vesca. These 18 genes are evenly distributed on chromosome 4 to 7. All of them had highly conserved domain sequences through analyzing the functional domain of the 18 members. The TCP members were divided into TCP-C and TCP-P according to the difference of domain and phylogenetic analysis. Phylogenetic tree analysis showed that F. vesca TCP proteins were grouped into two subfamilies, class I and class II. Expression profile analysis of the FvTCP family, which is related to the flower and fruit development from the project site, indicated that 13 members were related to flower development and five members were related to fruit development. These results suggested the important role of FvTCP proteins in fruit and flower development.

Trends in regional and chronological diversity of maize (Zea mays L.) germplasm in Pakistan

Maize germplasm was exclusively collected across Pakistan to probe the trends in genetic variability at regional levels and chronological periods. A total of 290 accessions were collected from 6 different regions. These were comprised of the following chronological order: 1980-1984, 1985-1990, 1991-2000, 2001-2007 and 2008-2016. These accessions represents maize growing provinces of Pakistan except Sindh. The performance of these entries were compared in the field and the data for different agronomic and yield related traits were subjected to statistical analysis. Mean comparison showed that Punjab region has highest mean grain yield followed by Azad Jammu & Kashmir (AJK). Regional differences in genetic diversity of maize germplasm were evident; AJK and Punjab possessed comparatively high genetic differences for various traits. Differences in the genetic variability across the region showed that various variability changing forces worked differently in different regions. Chronological studies showed that grain yield had been improving in Pakistan since 1980s. Highest grain yield was observed during the recent period (2008-2016) compared to earlier periods. Genetic diversity among available maize germplasm did not continuously reduce during the last 36 years based on the findings of this study. In the earlier years diversity showed increasing trend followed by declining trend. Highest genetic diversity was observed in the genotypes collected during 1980-1984 whereas, again there was boost in diversity during 1991-2000.  It has been observed that addition of newly developed and better performing genotypes into informal seed system initially increased the diversity followed by substitution of traditional accessions which led to change in genetic variation in Pakistan. The gradual change in patterns of genetic variability in maize at regional and chronological levels in Pakistan emphasizes the importance of conserving genetic resources to avoid genetic vulnerability and depletion

Biochemical, physiological and agronomic response of wheat to changing climate of rainfed areas of Pakistan

Designing the adaptation strategies by studying biochemical, physiological and agronomic response of wheat to climate change will be important for ensuring yield stability and economic sustainability in future. The current study was conducted under three variable climatic sites of rainfed field Pothwar viz. Islamabad (Optimum climatic conditions), URF-Koont Chakwal (Moderate temperature and water stress) and Talagang (high temperature and water stress) under four sowing dates (SD₁ = 21-30 Oct, SD₂ = 11-20 Nov, SD₃ = 01-10 Dec, and SD₄ = 21-30 Dec during 2013-14 and 2014-15) and five wheat genotypes. The study quantified the biochemical, physiological and agronomic response of wheat under different treatments. Stress in the form of drought and unfavorable temperature resulted in increase of total soluble sugar content (TSSC), total soluble protein content (TSPC) proline and leaf membrane stability index (LMSI), while decrease in relative water content (RWC), leaf area (LA), plant height (PH), biological yield (BY) and grain yield (GY). Leaf gaseous exchange parameters i.e. net photosynthesis (A_n), intercellular CO₂ concentration (C_i), transpiration rate (Tr) and stomatal conductance (g_s) remained highest under optimum conditions as compared to stress while opposite trend was observed for stomatal resistance (r_s). Correlation analysis among biochemical, physiological and agronomic traits showed that grain yield was positively correlated with RWC, LA, A_n, C_i, E, g_s, SPAD, PH and BY while negatively correlated with all other parameters. These results suggested to change sowing dates based on prevailing climatic conditions and use of tolerant cultivar to have higher sustainable crop productivity

Influence of deficit irrigation, sowing methods and mulching on yield components and yield of wheat in semiarid environment

Water scarcity is one of the leading crop limiting factor in the modern world of farming. Improving water use efficiency is one of the most serious challenge for agricultural scientists and water management experts. To evaluate the influence of sowing methods and mulch on wheat water productivity under deficit irrigation, experiments were conducted over a period of two years (2011-2012 and 2013-2013) at Research Farm of the University of Agriculture Peshawar, Pakistan. The experiments were laid out in randomized complete block design with split- split plot arrangement having three factors and replicated four times. The experiments consisted of three factors such as irrigation deficit (full irrigation, 20, 40 and 60% irrigation), sowing methods (raised bed and flat bed) and mulching (mulched and non-mulched). It was found that sowing methods, mulching and deficit irrigation had significantly affected yield and yield components of wheat.  Regarding sowing methods, raised bed cultivation resulted in higher number of grains spike¹, thousand grain weight, grain yield, biological yield and harvest index as compared to traditional flat bed sowing. Likewise, application of maize stover as a surface mulch enhanced wheat yield. In case of irrigation deficit, both full irrigation and 20% deficit irrigation resulted increase in thousand grain weight, grain spike^-1, biological and grain yield harvest index and water productivity. It can be concluded that raise bed cultivation, mulching and 20% deficit irrigation improved wheat yield and yield components under the semi-arid environmental

Variability in seed germination characteristics of Capsicum annuum L. and Capsicum frutescens L.

Seed germination, a phylogenetically conserved trait, is crucial for seedling establishment and survival in nature and can be used to establish phylogenetic relatedness among plant species. The current study evaluated seed germination characteristics of varieties of two closely related cultivated Capsicum species in West Africa in response to light, temperature and sowing depth under controlled environment. The varieties and species used in this study are C. annuum var. grossum, C. annuum var. abbreviatum, C. annuum var. accuminatum and C .frutescens var. baccatum. The results indicated that the varieties showed similar and overlapping germination requirements although considerable differences were also observed. However, the differences observed among the varieties do not provide enough evidence to conceive that the collections are two separate species but rather suggest that they are phylogenetically related. Additional comparative studies using DNA molecular profiling are needed to confirm the relatedness and variability in these species

Extraction and bioactivity from Jatropha Curcas L. leaves by steam distillation

Jatropha curcas L. has biological activities that can contribute to find new products. In this study, steam distillation at laboratory scale was applied to J. curcas leaves to assess the yield of essential oil and the bioactivity of the hydrolate. The effect of steam flow and bed porosity on the extraction yield was also determined, where it was observed that residence time was one of the influential factors in the yield of essential oil. The extracts were analyzed by GC-MS. Dibutyl phthalate, phytol, and diisooctyl phthalate were the majoritarian components. Research reports indicate that these components have biological activity. The greatest yield obtained was 0.38% on a dry weight basis. The bioassays showed that the hydrolate of J. curcas possessed toxicity against Spodoptera littoralis, Myzus persicae, Lactuca sativa, and Lolium perenne. The bioactivity of these products should be further explored, they have a promising future as a biocontroller

Soil microbial community response to nitrogen and phosphorous fertilization in a temperate forest nursery

Nitrogen and phosphorus application to forest nursery seedlings is known to influence various above-ground growth factors, such as plant composition and productivity, and the below-ground microbial community. In this study, we added N and P to forest nursery seedlings in a temperate forest region in China to examine how nutrient additions influence the plant biomass and soil microbial community composition through phospholipid fatty acids (PLFAs) analysis. The results showed that N had a significant effect on plant biomass, increasing the below-ground and the above-ground biomass, by 34 and 39%, respectively, and enhancing microbial community markers including fungal PLFAs (50%) and the ratio of fungal to bacterial PLFAs (35%) at 100 g nitrogen/1.3m², but didn’t change or negatively affect total PLFAs, bacterial PLFAs, gram-positive and gram-negative PLFAs and the ratio G^-: G⁺, or actinomycete PLFAs. Similarly, P increased the below-ground and above-ground biomass by 11.96 and 13%, respectively, and fungal PLFAs (35%) and the ratio of fungal to bacterial PLFAs (21%), at 80 g phosphorous/1.3m² but didn’t change or negatively affect total PLFAs, bacterial PLFAs, gram-positive and gram-negative PLFAs and the ratio G^-:G⁺, or actinomycete PLFAs. Principal component analysis explains 77% and 56% of total variations in PLFA composition in N and P treatment. In conclusion, N and P improved the seedling growth without negative effect on total PLFAs.

A neo-diversity group of Oryza sativa L. ssp. Japonica in northeastern China evaluated by large-effect SNPs

Rice breeding on the subspecies Oryza sativa L. ssp. japonica in northeastern China has been successful over a relatively short time. However, little is known about how the genetic structure of japonica has diverged as a result of artificial selection. In the present study, 189 single nucleotide polymorphisms (SNP) markers from gene coding regions were selected to characterize the diversity, phylogeny and population structure of four breeding groups in northeastern China, viz. modern japonica, historical japonica, exotic japonica, and indica varieties. Results suggested that the neo-diversity of japonica has formed gradually through introgression from other gene resources during the breeding selection. The genetic diversity (π) of modern japonica was lowest compared with historical japonica, exotic japonica and indica varieties, which implies a genetic bottleneck caused by the breeding selection. Population structure and phylogeny analysis proved that the modern japonica was independent of the historical japonica and exotic japonica groups

Phytochemical screening and antioxidant activity determination of some medicinally important plants of Balochistan

The present study was conducted to investigate the existence of phytochemical constituents and antioxidant activity of medicinally important plants such as Eremostachys thyrsiflora, Cousinia stocksii and Gaillonia macrantha found in the north of Quetta, Balochistan. Phytochemical analysis of selected plants showed the presence of phenolics, alkaloids, steroids, flavonoids, saponins, terpenoids and tannins. The total alkaloids, phenolics, flavonoids and saponins found in the crude methanolic extracts of Eremostachys thyrsiflora were 8%, 3.2%, 5.9% and 1.5%, while in Cousinia stocksii the proportions were 7%, 2.2%, 6.8%, 1% and in Gaillonia macrantha these phytochemicals were found to be 8%, 2.8%, 0% and 0.5% respectively. In-Vitro antioxidant activities were studied spectrophotometrically by using total antioxidant activity, free radical scavenging power (DPPH) assay, ferric reducing antioxidant power assay and reducing power assays. The total antioxidant capacity of the E. thyrsiflora, C. stocksii and G. macrantha were determined and found to be 2.31, 5.44 and 9.15 mg ascorbic acid equivalent/ gram of plant extract respectively. The crude methanolic extracts of all these plants revealed antibacterial activity against S. typhi, E. coli, K. pneumonia and S. aureus and antifungal activity against S. cerevisiae. These results indicated that the crude methanolic extracts of the selected plants contained medicinally bioactive constituents which could be used for the treatment of different diseases and could also be used to reduce the oxidative stress.

Physio-biochemical responses of apple-of-sodom [Calotropis procera (Aiton) W. T. Aiton] to vehicular pollution

Vehicular traffic has become a primary source of pollution along the roadsides which adversely affects plants and other biota. This study was conducted to assess the effects of vehicular pollutants on Calotropis procera growing at different sites along two major roads [Pindi Bhattian to Kala Shah Kaku (M-2) and Lahore to Gujranwala (G.T. road)] in the Punjab province of Pakistan. Control samples of Calotropis procera were collected at a distance of 50 m away from the roads. The photosynthetic rate (A), stomatal conductance (g_s), transpiration rate (E), water use efficiency (WUE), contents of photosynthetic pigments, total free amino acids and antioxidant activity of C. procera were determined. The results showed significantly lower contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids in C. procera along the roadside as compared to control plants. Similarly, stomatal conductance was also significantly lower, as was the case with photosynthetic and transpiration rates in C. procera growing along the roadside. The overall decrease in photosynthetic rate of C. procera was 34.90% and 44.79% along M-2 and G.T. road, respectively as compared to control. Reduced photosynthesis in roadside plants resulted in higher levels of water use efficiency. The higher contents of free amino acids and antioxidant activity were recorded and might be ascribed to the activation of the defense system of plants to cope with the detrimental effects of vehicle-related air pollutants. The correlation of different attributes of C. procera with traffic density was significant that suggested the direct impact of vehicular emissions on this species. Hence, C. procera can be used as a biomonitor of vehicular pollution

Dynamics of the production process of sweet potato cultivated in the sandy soil conditions in Romania

Sweet potato or bathe [Ipomoea batatas (L.) Lam], a drought-tolerant plant, originates in Central America and now cultivated on large areas in China, India, Japan, Africa, the US, Mediterranean areas of Europe in a soil having moderate fertility.  In Romania there are about 439,000 ha of sandy areas and due to more and more frequent changes of climate, it is necessary to find some species and varieties, which can withstand the thermohydric stress.  In this respect, during the period 2015-2017, at Dăbuleni, located in southern Oltenia, Romania we have studied five sweet potato varieties of Korean origin, with different growing seasons, (Yulmi, Juhwangmi, Hayanmi, KSP 1 and KSC 1), in order to determine the plant's reaction to the color of the mulch used to protect the soil and the time of harvesting. The results showed that most of the genotypes had reached a maximum production potential at 120 days from the planting of the shoots in the field (24232.1-37746.1 kg / ha, in the variants with transparent mulch and 22327-38587.7 kg / ha, in the variants with smoky mulch). The exception is the Juhwangmi variety, which, being earlier, achieved the maximum yield when the harvest was carried out 110 days after planting, irrespective of the color of the mulch (47044,4-48285 kg / ha). Harvesting sweet potato varieties outside the optimal age of the plant maturity, results in the reduction of production and the depreciation of its quality, having negative repercussions in winter storage.

Spatial analysis of selceted soil parameters in potato growing areas of mountainous region of Gilgit-Baltistan, Pakistan

The study explores the spatial variability of soil parameters in potato growing valleys of CKNP region, Gilgit-Baltistan, Pakistan. Soil sample’s location was documented through handheld GPS. Investigation reveals that soil of study area varies from loam to silty loam having pH values from 7.23 to 8.30 along with 0.45-1.39 electrical conductivity. Soil organic matter was found adequte in 1.04% tested samples. None of the samples had adequate level of NO₃-N. However, adequate PO₄-P and K was detected in above 90% tested samples. GIS maps indicates that soil parameters were spatially distributed amongst the valleys or even within the same valley. Digital mapping is an important action that provides vital information about soil nutrients, leading to a sustainable agriculture operation. GIS maps will help potato growers in crop management decisions like efficient utilization of fertilizer, reducing cost of production which will be resulted in increase productivity. Study will improve farmer’s livelihood and play a vital role in reducing environmental pollution

Assesssment of human impact on the structure and composition of Lasdana forest district Bagh, Azad Jammu and Kashmir, Pakistan

Natural forest resources of moist temperate forests of Himalayas are severely threatened due to over exploitation by rural population for their domestic usage. Six forest sites were selected to examine the anthropogenic impacts on natural forests in which 3 sites were disturbed and 3 were control sites with natural vegetation without any disturbance. Total 102 species were recorded belonging to 42 families and the most dominant family was Lamiaceae followed by Poaceae. Dominant tree species of the area were Abies pindrow having IVI 90.94 and Pinus wallichiana has 69.51 IVI respectively. The shrub layer was dominated by Viburnum grandiflorum having IVI (29.2) followed by Berberis lycium (16.91) while herb layer was dominated by Fragaria nubicola (14.93), Bupleurum falcatum (12.69) and Impatiens bicolor (12.20). Average Simpson's diversity was 0.962; average Shannon diversity was 3.63; average species richness was 1.48; average species evenness was 0.91 whereas average maturity index was 42.18. Average tree density was 410/ha; average stump density was 360/ha; average stem to stump value was 2.08 whereas average regeneration rate was found to be 263.33/ha. The quantified structural forest attributes reveal a severe intensity of human pressure on the local forests. There is a serious threat to the ecosystem services provided by the local forest reserves and reflect the need of immediate merasures for the conservation and sustainable use of the forest resources. 

Floristic, frequency and vegetatio-biological spectra of Murree-Kotli Sattian-Kahuta National Park, Pakistan

Present study was aimed at documenting floristic, frequency and vegetatio-biological spectra of the vascular plants distributed in 246 sampling sites of the Murree-Kotli Sattian-Kahuta National Park, Punjab, Pakistan. The study area is situated at the latitude value of 33º21′ to 34º01ʹ N and longitude value of 73º11ʹ to 73°38ʹ E in the Rawalpindi, and comprised of total land area of 934 Km². In all, 352 plant species distributed across 150 genera and 82 families were recorded from the 246 sampling stations. The flora included 330 natives (93.75%), followed by weeds (14 spp., 3.98%), cultivated & naturalized (3 spp., 0.85% each) as well as endemic and introduced (1 sp., 0.28% each). According to floristic life form spectra, therophytes were dominated in the area (31.25%), followed by hemicryptophytes (28.13) and nanophanerophytes (11.36), while the frequency spectra revealed the domination of hemicryptophytes (32.07%), followed by nanophanerophytes (21.62%) and therophytes (20.77%). Hemicryptophytes were the leading class in the vegetation spectra (32.07%), followed by nanophanerophytes (21.25%), therophytes (20.77%) and macrophanerophytes (13.48%). Homogeneity analysis exhibited a significant difference between floristic and vegetation life form (X² = 17.26, p<0.05). The proportion of hemicryptophyte increased from floristic to vegetation spectrum; whereas therophytes decreased from floristic to vegetation spectra. This study concludes that floristic life-form spectra showed clearer picture than that of Raunkiaer's classification and correctly explained the existing climatic conditions of the studied area. Besides, it is suggested that the vegetation spectrum requires the meticulous physiognomy coupled with ecological factors if worked in smaller areas to be deliberated

Anatomical and morphological structure of Peganum harmala of Almaty region and its therapeutic properties

Peganum harmala L. (harmal) is a perennial herbaceous, multistage plant, having an ancient history of use for disinfection purposes, and in modern medicine, the relevance to the widespread use of the multi-purpose therapeutic properties of this species has increased. Evaluation of raw material base of harmal will allow balanced use as a dye and alkaloid medicinal plant in certified medicine. Peganum harmala L. showed resistance to external influences, since the influence of various environmental factors on the soil cover of southeast Kazakhstan led to an increase in degraded areas, in which it was found abundant growth of this plant. The results of geobotanical studies carried out over the last 2015-2018 show that the raw material base of Peganum harmala L. causes wide application in medicine. In connection with the rich resource of Peganum harmala L.,it shows interest of local and domestic consumers for the application of raw materials in the form of an extract. In laboratory conditions, to identify signs of resistance to various conditions, complex studies were conducted to the the morphological and anatomical structure. Morphological characteristic and the anatomical structure of Peganum harmala L. were determined. Signs of stability are ring-shaped sclerenchyma in stems and roots, as well as the presence of a two-sided columnar mesophyll in leaves. To assess the therapeutic properties Peganum harmala L. experimental studies were conducted in the laboratory of pharmacodynamics and immunopharmacology and the influence of the water-alcohol extract of this plant on the metabolism of rats with alimentary obesity was investigated

Medicinal plant diversity used for livelihood of public health in deserts and arid regions of Sindh-Pakistan

Ethnopharmacological surveys require novel approaches to obtain successful hits in drug discovery. The objectives of the present study were to document the traditional uses of medicinal plants from the Deserts of Sindh and to authenticate the documented traditional uses. The traditional uses were documented from informants using semi-structured questionnaires and open-ended interviews. The data were analyzed using relative frequency of citation (RFC), Use value (UV), Informant consensus factor (ICF), Fidelity level (FL) and Relative Importance (RI), and their uses were validated through Metanalyses (MAs) and Systemic reviews (SRs). Overall, 74 plant species were reported from 207 informants and their traditional uses were validated from 299 published ethnobotanical studies. Aloe vera and Ricinus communis were more frequently cited in published literature. Blepharis ciliaris and Echinops echinatus either due to lack of pharmacological or phytochemical studies. The leaves were the most frequently used (36 reports), and decoctions (27 reports)) followed by powder (26) were predominantly reported. The UV varied from 0.49 (Cynodon dactylon) to 0.2 (Tribulus terrestris); the RFC from 0.38 (Calotropis procera) to (Aerva javanica); and the RI from 50.74 (Acacia nilotica) to 5.61 (Salvia santolinifolia). The maximum FL was found for 14 species, and the ICF varied from 0.61 (Digestive disorders) to 0.16 (Nervous disorders). The deserts (Sindh-Pakistan) provides many important plant species with most authenticated traditional uses. The plant species having most authenticated uses, highest correlated ethnobotanical index values, and lacking pharmacological or phytochemical studies, may yield desired results in limited time with most cost-effective resources

A study of wild plant species of Brassicaceae family in Bayburt region of Turkey

The Brassicaceae (Cruciferae) is one of the most important groups and it has 338 genera and 3709 species around the worldwide. Plant samples of the Brassicaceae family were collected and photographed during the vegetation period of 2017. The plant samples and the photos were taken from their natural habitat between 23 April and 11 August 2017. The locations were determined based on differences in geographical features with variable ecological conditions. 38 genera and 80 species and subspecies were identified from different locations of the study area. Heldreichia bupleurifolia Boiss. subsp. rotundifolia, Aethionema caespitosum, Thlaspi lilacinum, Tchihatchewia isatidea, Bornmuellera cappadocica, Aurinia rupestris subsp. cyclocarpa, Alyssum stylare, Alyssum pseudomouradicum, Alyssum peltarioides Boiss. subsp. peltarioides are endemic taxa for Bayburt.

Trichoderma aspereullm ACCC30536 inoculation differently regulates the time-course expression of five indole-3-acetic acid amido synthetase genes and the levels of IAA, SA and JA in Populus davidiana × P. alba var. Pyramidalis

Some indole-3-acetic acid amido synthetases (GH3 proteins) were confirmed to catalyze the connection between IAA, SA or JA with amino acid to regulate hormone dynamic balances in promoting plant growth; they can also improve plants’ resistance to stress through activating SA, JA and ethylene signaling pathways. Trichoderma spp. are widely-known beneficial biocontrol agents. However, the expression pattern of plant GH3 genes induced by Trichoderma remained unexplored. In this study, five GH3 genes in Populus davidiana × P. alba var. pyramidalis (named PodaGH3-1, PodaGH3-2, PodaGH3-5, PodaGH3-9 and PodaGH3-10) were cloned. Their characteristic analysis showed that the five PodaGH3s genes were highly conservative and closely related at the residues linked to ATP binding with IAA or JA, and their expression levels changed obviously under Trichoderma inoculation. Moreover, IAA, JA and SA contents showed a fluctuating yet increasing trend during the 72 hours when poplar seedling rhizosphere was colonized by Trichoderma. In summary, all the five PodaGH3s could be activated by the interaction between biotrophic Trichoderma and poplar seedlings.

Comparative assessment of detached leaflet and tuber disc assays for studying the aggressiveness of different isolates of Phytophthora infestans

Study of the aggressiveness potentials of a pathogen has wide applications in plant pathology for determination of its population composition and consequent disease control methods in a given environment. Both, laboratory and field experiments are in general use to study the aggressiveness characteristics of plant pathogens. Comparative efficacy and reliability of a particular method employed for such studies could greatly reduce labor hurdles, time and associated costs. In this experiment, we evaluated and compared detached leaflet and tuber disc methods for the reliability of results of the aggressiveness characteristics (percent disease severity, latent infection period and lesion area and area under lesion expansion curve) of 15 isolates of the late blight pathogen (Phytophthora infestans) which were collected from different locations. In general, both methods revealed similar and consistent results for the aggressiveness rankings of different isolates; however, numerical values for aggressiveness components significantly varied among the tested isolates in each method. Results suggested that detached leaflets and tuber discs assay could be used as reliable and efficient methods for studying the aggressiveness characteristics of P. infestans

Development of specific real-time PCR primers for detecting Pseudomonas syringae pv. Actinidiae in China

Pseudomonas syringae pv. Actinidae (Psa) is the most devastating disease of kiwifruit cultivation. In this study, to detect Psa in China high specifically and sensitively, a method of real-time PCR was developed. The specific primers YF32/YR32 was set for the 590 bp hrpW gene fragment, with amplicon of 248bp in length. The standard curves of real-time PCR clearly showed a suitable condition of real-time PCR and an excellent linear of the data. The specificity and sensitivity assay showed this method could specifically discriminate between Psa and Psa-related pseudomonads and sensitivity threshold was 100fg/μL. In the actual effect validation experiments, the results of all of 5 twig samples with symptoms were positive, and 3 of 5 symptomless samples were positive with minimum DNA concentration 8.45×10^‐5ng/μL. The methods of this study could make an important contribution for the prevention and diagnosis of the bacterial canker disease of kiwifruit in China

Chitinolytic activity of the indigenous Trichoderma spp. from the north west of Pakistan against the fungal phytopathogens

Chitinases are the enzymes considered as an important biocontrol mechanism for the putative antifungal activity. Here we report the chitinolytic activity of the indigenous strains of Trichoderma previously isolated from the North Western regions of Pakistan. The different strains of T. longibrachiatum TMK5, TMK6, TMK9, TMK20 and TMK21, and T. virens TMK8 isolated from the Malakand region, and T. longibrachiatum TKK3, TKK4 and TKK6 isolated from the Karak areas were included in this study. The strains were screened for their activity on the specific chitin synthetic medium in vitro at pH 4.7. The formation of purple colored zones depicted the chitinase activity by the fungi and the intensity of the colored zones was used as the criteria for the assessment. The highest activity was shown by T. longibrachiatum strain TKK4 followed by the strains TKK3, TMK5, TKK6, TMK20, and TMK21. The enzymes were then extracted in the modified Richards’s medium. The strain TMK21 showed the highest N-acetyl-β-D-glucosaminidase activity of 0.017 umol/ml/min. Endochitinase activity was noticed by the extent of reduction of colloidal chitin suspension by the tested strains. The highest endochitinase activity was shown by the strain TMK9. The strain TMK20 produced the highest enzyme unit (0.503 EU), while on the other hand, the strain TMK9 had the lowest value (0.033 EU). The crude enzymes were then applied against the phytopathogenic fungal isolates originated from the local diseased vegetables (Green Chili, Onion, Ridge Gourd, Okra, Bottle Gourd, Eggplant, Bitter Gourd and Spinach) including Fusarium spp., Alterneria spp. and Aspergillus spp. The partially purified enzymes extracted from T. longibrachiatum strains TMK20 and TMK21 consistently inhibited the different phytopathogenic fungi (up to 100%). This study demonstrated the inhibitory role of the chitinolytic enzyme extracts against the fungal pathogens.

Control measures of root rot fungal pathogens by producing resistance against twelve wheat cultivars under greenhouse in Nebraska State of USA

Susceptibility or resistance against three strains of root rot pathogens of twelve wheat cultivars were analyzed in Nebraska State of USA. It was mainly focused on the screening of twelve wheat varieties against Fusarium graminearum strain W433 and two strains (G256 and W1624) of Rhizoctonia solani. These pathogens contributed to significant yield reduction. Agar plug inoculation and biological control agents culture suspension techniques were used for experimental trials. The disease severity was measured against three fungal strains by agar plug inoculation method (APIM). It was observed that wheat cultivars (WC) Freeman (2.00) and NW07505 (2.50) were moderately resistant while Overland (3.25), Overland FHB10 (3.00), Panhandle (3.75), Ruth (3.50), Mattern (3.75), RedHawk (3.00) and SY-Wolf (3.25) rated as susceptible against Fusarium graminearum strain W433. Overland FHB10 (1.75), Panhandle (2.00), NW07505 (3.00) showed moderate resistance and Freeman (4.00), Ruth (3.75), Mattern (4.25), McGill (4.00) rated as susceptible against Rhizoctonia solani strain G256. Similarly, Rhizoctonia solani strain W1624 showed less disease severity against Freeman (2.00), NW07505 (2.00), SY-Wolf (2.00) while more severity appeared against Overland (3.50), Robidoux (3.50), Ruth (4.00), Mattern (4.00). According to statistical evaluation, all artificially inoculated wheat cultivars (WC) with W433 strain showed almost similar shoot length (L) while fresh weight (FW) of shoot was slightly variable between treated and non-treated varieties. Similarly, root length, root FW and dry weight (DW) of wheat lines appeared significantly similar. It was estimated that all artificially inoculated WC indicated slightly reduced biomass in comparison to control after six week harvesting periods. Shoot length of five artificially inoculated WC with strain G256 as V₁ (Freeman), V₆ (Ruth), V₇ (Settlers), and V₉ (Mattern) showed less weight when compared with control. Wheat lines V₆ (Ruth), V₇ (Settlers), V₉ (Mattern) and V₁₁ (RedHawk) also reduced shoot FW weight after pathogen inoculation. Dry weight of shoot was also reduced in seven varieties after inoculation of W1624 strain. It was noted that Rhizoctonia strain W1624 was more virulent to cause root rot disease and reduced more biomass of yield components in comparison to Rhizoctonia strain G256

Relationships between mycorrhizae and root hairs

Mycorrhizal extraradical hyphae and root hairs coexist on the root surface and are responsible for water and nutrient absorption from the soil. Root hairs generally are a preferential adhesion point colonized by ectomycorrhizal hyphae, and eventually are suppressed or incorporated in the fungal mantle. However, arbuscular mycorrhizal (AM) fungi occasionally penetrate root hairs of host plants. A root hair feature is not a reliable indicator of mycorrhizal dependency in plants, as well a mycorrhizal growth response. AM fungal inoculation has increased and reduced effects on root-hair growth (including length, density, and diameter), which is related mainly with auxin and some potential factors (i.e. P and glucose). Such AM effects on root hair can be regulated by substrate P and soil water levels. Root hairs have the preponderant role in soil adhesion under sand or semi-arid conditions, in comparison with extraradical hyphae. In addition, root hairs have higher effectiveness in P acquisition and utilization in biomass production than extraradical hyphae under P-deficient conditions. Under drought stress, AM fungi almost replace the absence of root hairs to enhance plant tolerance through alternative pathways.

Streptomyces sp. MM-3 from rhizosphere of Psidium guajava: a potential candidate for protease with dehairing properties

Soil is the richest medium for isolation of microbial flora especially genus Streptomyces as potent source of extracellular enzymes. Soil samples from rhizosphere of guava plant (Psidium guajava) were screened for proteolytic bacteria. Among all isolates, Streptomyces sp. MM-3 showed best proteolytic activity by utilizing agro-based substrates like malt, soybean, wheat bran and peels of ground nuts as carbon/nitrogen sources. Optimum incubation time for enzyme production was 96h (420U/ml), while optimum age and size of inoculum was 24 h (95 U/ml) and 10% (482 U/ml), respectively. Maximum units of protease were observed with 0.5% starch (396U/ml) and 1% gelatin (439 U/ml). Application of partially purified protease on sheep and goat skins resulted in a highly promising dehairing efficiency as an alternative of lime-sulfide chemical unhairing process. Enzyme-treated dehaired leather was processed further through other pre-tanning steps like liming, fleshing, deliming and pickling. Final leather crust from chrome blue pelt showed high degree of tear strength (40.93 ± 4.21) N/mm k=2, good tensile strength (16.58 ± 2.31) N/mm k=2 and elongation (155.08 ± 5.97) N/mm k=2 comparing to lime-sulfide unhairing process. Other significant advantages of enzymatic dehairing were total recovery of hairs, simplification of pre-tanning process and reduction in use of sodium sulfide. Thus producer strain Streptomyces sp.MM-3 of soil origin emerged as a potential candidate for the production of protease using low-cost production medium to be utilized by leather industry

Optimization of pectinase production from Geotrichum candidum AA15 using response surface methodology

Pectinolytic enzymes are used in industries involving in fruits and vegetables processing, wine making, retting and degumming of fiber crops, extraction of olive oil, treatment of pectin containing waste water and in the fermentation of coffee, tea and cocoa. Pectinase production from bacteria and fungi has been reported widely, however, very few reports are available for pectinolytic yeasts. This research was carried out to study the parameters affecting pectinase production from an indigenously isolated yeast strain, Geotrichum candidum AA15, using statistical tools. Plackett-Burman design revealed initial pH of the medium, inoculum size and substrate concentration as significant factors. Subsequently, optimum conditions for pectinase production were determined using Box-Behnken design. The data showed that the strain produced 0.250 IU/ml pectinase under optimized conditions using inoculum size, 3%; substrate concentration, 0.75%; and a starting pH of 5.3. Time course studies of the enzyme production revealed that the pectinase production was associated with the growth and optimum enzyme production was achieved after 48 h of cultivation. The presence of isozymes with approximate molecular weights of 60 and 66.2 kDa was indicated by SDS-PAGE and in-gel visualization of enzyme activity. These results provide a merit to study the strain further to explore its biotechnological potential.

Identification of control agents against melon wilt disease in laboratory and field in NE China

The pathogenic bacteria of Fusarium oxysporum were obtained through tissue separation. The inhibition of 13 fungicides on growth of Fusarium oxysporum was determined in laboratory. The results showed 30% Trimethoprim WP and 10% difenoconazole WG significantly inhibited the growth of Fusarium oxysporum at EC₅₀ of 0.0025μg / mL and 0.8120μg / mL, respectively. Whereas, 99% hymexazol TF,50% chlorothalonil WP, 70% thiophanate-methyl WP, 50% thiram WP, fairly inhibited the growth at EC₅₀ <10μg / Ml. The 50% iprodione WP, 50% procymidone WP, 65% Oxadixyl WP, 15% triadimefon WP, 70% mancozeb WP, 10% polyoxin WP, and 65% Tiezene WP provided less effects. The 30% trifloxystrone WP and 10% difenoconazole WG were tested in field due to their well performance in laboratory.The control efficacy was significantly higher than that of 30% Rui Miaoqing that functioned as control

First report of Cladosporium cladosporioides instigating leaf spot of Solanum melongena from Pakistan

Solanum melongena is a popular and edible vegetable crop of Pakistan. Outbreak of irregular necrotic leaf spots with darker margins was observed. Initially the morphological identification was executed by studying the pathogen. On the bases of olive green colonies, greenish black elongated conidiophores and ellipsoidal branched conidia, the pathogen was identified as Cladosporium cladosporioides. In genetic characterization primers ITS1/ITS4 amplified~650bp DNA fragment of total genomic DNA. BLAST analysis of region (KY290222) exhibited 99% similarity with many strains of C. cladosporioides present in GenBank. The healthy leaves of S. melongena were further exposed to spores of C. clasosporioides to confirm its pathogenicity

Remote sensing of phytoplankton fluorescence in northern Arabian Sea 17-708

This paper is about remotely sensed phytoplankton fluorescence, its monitoring and spatio-temporal mapping. We examined several remote sensing variables provided by the National Aeronautics and Space Administration (NASA) by the GES DISC Giovanni system. These variables are Normalized Fluorescence Line Height (nFLH), Photosynthetically Active Radiation (PAR), chlorophyll a (chl-a), Diffuse Attenuation Coefficient at 490 nm, and Remote sensing reflectance 678 µm monthly data during April, 2011 to March, 2012 from the Moderate Resolution Imaging Spectro-radiometer (MODIS) satellite sensor data. Results highlight the use of selected variables which are useful for mapping ocean productivity and its spatial patterns.

Unusual dominance of harmful microalgae Pseudo-nitzschia delicatissima cf. (Cleve) Heiden in the coastal waters of Jeddah, central Red Sea

Dominance of harmful pennate diatom Pseudo-nitzschia delicatissima was observed during a regular environmental monitoring study carried out in the coastal waters of Jeddah, Saudi Arabia. Neither any discoloration of water nor any fish kill was reported during the period of this specific phenomena. This diatom species dominated the area with a higher percentage (97.5%) of the total phytoplankton community encountered. Apart from these, the occurrence of harmful algal bloom causing heterotrophic dinoflagellates was also noticed in a few numbers. Phytoplankton biomass in terms of chlorophyll a obtained was 4.1 mg m^-3 and the silicate values (1.92 µmol l^-1) were comparatively higher than the other inorganic nutrients. Zooplankton abundance was relatively low (705 ind. m⁻³) and were dominated mainly by copepods (79.9%) followed by mollusc and decapod larvae