Variations in water relations, stomatal characteristics, and plant growth between quinoa and pea under salt-stress conditions

Salinity is a primary restrictive factor for crop growth at both the cellular and whole plant levels. The effects of salinity on water relations, stomatal morphology and physiology, and seedling growth in quinoa and pea were investigated to compare the salt tolerance mechanisms of these two species. The seedlings of quinoa and pea were cultivated in Hoagland’s solutions supplemented with different NaCl concentrations (0, 100 and 200 mM). For quinoa,the relative water content, transpiration ratio, osmotic potential, stomatal conductance, stomatal density, and stomatal length were all reduced significantly by salt stress. Interestingly, a greater stomatal conductance of the abaxial surface in quinoa was found during salt stress in comparison with the control. Similar trends (root > stem > leaf) were found for leaf water potential in quinoa and pea. For different organs, quinoa possessed greater leaf water and osmotic potentialsthan pea, indicating that quinoa might limit the translocation of inorganic ions to maintain the water balance. The turgor pressure in the two species increased significantly, which could play an important role in sustaining seedling growth. In conclusion, quinoa was less affected by salinity, which was verified by the different physiological responses of stomatal and plant water states.

Rhizobacteria and silicon synergy modulates the growth, nutrition and yield of mungbean under saline soil

Osmotic stress and imbalance nutrients uptake due to salinity stress are major threats that cause decline in growth and yield of crops. This problem is very common in arid and semi-arid regions because of low precipitation and bad quality of irrigation water. Plants also produced higher level of stress generating ethylene via 1-aminocyclopropane-1-carboxylic (ACC) acid when cultivated under limited supply of water. However, inoculation of ACC deaminase producing plant growth promoting rhizobacteria (PGPR) can grant resistance against salinity to crops. On the other hand, silicon (Si) application also increase the productivity of the crop under salt induced stress. This study was conducted to examine the influence of sole and combined application of ACC-deaminase containing PGPRs and Si on mungbean under salinity stress. Prior to sowing, seeds were inoculated with peat based bacterial culture. Silicon was applied at 150 kg ha^-1 at the time of sowing using the source as CaSiO₄ (Calcium Silicate). After two and half month’s crop was harvested. Combined application of PGPR + Si caused a significant improvement in growth and physiological attributes of mungbean under salinity. A significant improvement in K (2.30, 0.33 and 0.52-fold) and reduction in Na concentration (0.66, 0.55 and 0.56-fold) in leaves, shoot and seeds, respectively, validated the efficacious role of combine application of PGPR and Si regarding mitigation of salinity stress in mungbean. Significant increase in number of nodules, leaves and grain yield with PGPR + Si over control confirmed the ameliorative effect on mungbean under salinity stress. In conclusion, PGPR + Si is more effective compared sole application for enhancing growth, nutrients concentration and yield in mungbean under salinity stress. 

Functions of folic acid (Vitamin B9) against cytotoxic effects of salt stress in Hordeum vulgare L.

The function of vitamin B9 (folic acid) on mitotic activity and chromosome behaviors in meristematic cells of barley (Hordeum vulgare L. cv. ‘Bülbül 89’) seeds germinated at different salt concentrations were studied. The prohibitory impact of salinity on mitotic index significantly increased in parallel with increase of salt concentrations as compared to control group. The mitotic inhibition was 33.3% at 0.35 M salt concentration. Furthermore, the mitotic inhibition reached the lowest value (46.6%) after treatment with folic acid alone. The frequency of chromosome aberrances in meristematic cells of barley seeds treated with folic acid alone demonstrated a marked increase (approx. 32%) compared to the control seeds. The frequency of aberrances were gradually increased with increasing salt concentrations. In addition, folic acid pretreatment was statistically ineffective in recovering of the unfavourable effect of different salt concentrations on mitotic activity while it reduced the harmful effects of salinity on chromosome aberrances particularly at high salt concentrations

Modulation in growth, photosynthetic pigments, gas exchange attributes and inorganic ions in sunflower (Helianthus annuus l.) by strigolactones (GR24) achene priming under saline conditions

Plants respond to various abiotic stresses in a complex way, depending upon their severity through cellular, morphological and physiological modifications. Phytohormones are signaling molecules which mediate plant growth and development. They modulate plant physiological responses to acclimatize stress like salinity. Phytohormones interact with each other to alleviate abiotic stress. Striglactones are relatively newly discovered phytohormones and are proposed to have their role in stress responses like those of salinity. A synthetic analogue of strigolactones GR24 was used to explore its role to ameliorate adverse effects of salt stress on sunflower plants. Achenes of two sunflower hybrids (FH-593 and FH-596) were primed with four concentrations of GR24 (water (0), 0.001, 0.01 and 0.1 mg L^-1) and grown under two salt regimes i.e. non-saline and 120 mM NaCl in pots. Salt stress significantly decreased growth attributes while GR24 showed a positive effect to alleviate salt stress. Pre-sowing achene treatment with GR24 significantly enhanced plant biomass and shoot length. Salinity markedly decreased photosynthetic pigments and net CO₂ assimilation, stomatal conductance and transpiration. Chlorophyll contents and gas exchange attributes of both sunflower hybrids showed a non-significant response to GR24 treatment. However, carotenoids contents increased with GR24 pre-sowing achene treatment. Salinity significantly raised the contents of Na⁺ contents but decreased that of Ca²⁺ and K⁺ ions in both shoot and root. The GR24 application enhanced the Na⁺, K⁺ and Ca²⁺ in shoots and roots

Evaluation of grain yield in fifty-eight spring bread wheat genotypes grown under heat stress

In Mediterranean region, terminal heat stress in late sown wheat is one of the major constraints to harvest good wheat yield. Therefore, this is desired to identify and develop wheat varieties that can grow under heat stress conditions of Mediterranean environments. In this study, fifty-eight wheat genotypes of diverse origin were planted at optimal (optimal conditions; October 1, 2015) and late sowing (high temperature; March 1, 2016) times at the Agricultural Research Area, Cukurova University, Adana, Turkey. Wheat sown at optimal time had better growth and yield-related traits, which lead to better grain yield. Considering the correlation between various yield-related traits. When planted at optimum time, the highest grain yield and related traits were recorded from the genotype ‘Misr-2’ that was followed by genotypes ‘Shandaweel-1’ ‘Misr-1’, ‘Sakha-94’ and ‘Giza-171’, while the genotype ‘Shirogane kamugi’ produced the lowest grain yield. In late sown (heat stress conditions) crop, grain yield of all tested genotypes was significantly decreased. In this regard, the genotypes ‘Norin’ and ‘Eagle rock’ were more sensitive to high temperature, while genotypes ‘Misr-1’ and ‘Misr-2’ were tolerant to heat stress and produced the highest yield under late sown conditions. Based on GGE biplot analysis, genotype ‘Misr-2’ performed better both under optimal and late sown conditions, this was followed by genotypes ‘Misr-1’ and ‘Shandaweel-1’. Biplot analysis indicated that the genotype Misr-2’ is highly adaptive to late sown (heat stress) condition, this was followed by the genotypes ‘Misr-1’ and ‘Shandaweel-1’. These genotypes could be used in future breeding programmes aimed to develop heat tolerant wheat genotypes and more appropriate for cultivation under a changing climate. In conclusion, correlation, stepwise regression and biplot analysis could be successfully used for the identification of heat adaptive wheat genotypes. The genotypes ‘Misr-2’, ‘Misr-1’ and ‘Shandaweel-1’ may be recommended for planting under hot environmental conditions and may be included in breeding program aimed to develop heat tolerant varieties for the Mediterranean region.

Gentiopicrin and swertiamarin contents in Gentiana macrophylla Pall. roots along elevation gradient in Donglingshan meadow, Beijing, China

Quality and quantity of chemical constituents in medicinal plants highly depends on environmental conditions. The contents of active constituents in Gentiana macrophylla Pall. may vary among different altitudes of mountain meadows and are affected by environmental factors. The aim of this study was to find the effect of environmental factors on Gentiopicrin and Swertiamarin contents in G. macrophylla roots along elevation gradient of Donglingshan meadow. Plant and environmental data were collected from 15 altitudes (50m distance away from each other) along 1600-2301 m elevation gradient by using Braun Blanquet approach. The contents of Gentiopicrin and Swertiamarin were estimated by using High Performance Liquid Chromatography method. Relationship among Gentiopicrin and Swertiamarin contents, soil and other environmental variables was depicted by using Canoco 5 and SPSS software. Regression analysis showed that Gentiopicrin is strongly affected by Elevation, Slope aspect, Soil pH, Soil temperature, Total Nitrogen. Swertiamarin concentration is strongly affected by slope, soil pH and Magnesium. Gentiopicrin contents have statistical significant relation with elevation gradient as compared to Swertiamarin. Insight of important bioactive compounds provided by this study would be helpful for medicine quality control, conservation of G. macrophylla and discovery of new drugs.

Mitigation of drought stress in maize through inoculation with drought tolerant ACC deaminase containing PGPR under axenic conditions

Drought is one of abiotic factors that hampers the growth and yield of crops via an elevated level of ethylene too, inspite of limited nutrients supply. The ACC deaminase containing PGPR can mitigate drought stress in crops by decreasing the synthesis and accumulation of ethylene. As maize is widely cultivated cereal and fodder crop, a glass jar study was conducted for screening of drought-tolerant ACC deaminase containing PGPR under axenic condition. Under various levels (i.e., 0, 10 and 20%) of polyethylene glycol (PEG) induced drought stress, some of the ACC deaminase containing PGPR significantly enhanced shoot and root length, shoot fresh and dry weight and root fresh and dry weight in maize seedlings. Further, a significant improvement in photosynthetic pigments formation and nutrients concentrations i.e., NPK in maize shoot validated the efficacious functioning of PGPR strains, Pseudomonas aeruginosa, Enterobacter cloacae, Achromobacter xylosoxidans and Leclercia adecarboxylata regarding reduction in ethylene accumulation in maize seedlings under drought. Pseudomonas aeruginosa, Enterobacter cloacae and Achromobacter xylosoxidans are previously documented but Leclercia adecarboxylata is a new drought tolerant ACC deaminase containing PGPR that might have the potential to alleviate drought stress by improving root elongation, NPK uptake and possibility decreasing ethylene in plants

Phenotypic variation in waterlogging stress tolerance among wheat cultivars and its wild relatives

Waterlogging is one of the limiting factors affecting global wheat yield including Pakistan. Its harmful effects on wheat crop depend on growth stage and type of cultivars. The main objectives of this study were to screen different wheat cultivars/accessions against waterlogging stress at imbibition stage and then at two leaf stage for those cultivars exhibiting tolerance at imbibition stage. In total one hundred and nineteen wheat cultivars/accessions were screened at imbibition/germination. These 119 cultivars/accessions were grown in Indian subcontinent during different time periods from early 20^th century till present. Seeds after sowing were immediately exposed to waterlogging stress for 8 days. None of the cultivar/accession showed germination during eight days of stress. Waterlogging stress was terminated and kept for revival for one week under normal conditions. Sixteen cultivars/accessions showed revival (germination) in one week time. These 16 cultivars/accessions, along with three randomly selected cultivars, were further screened at two leaf stage against waterlogging stress for 16 days. These cultivars/accessions responded differently against waterlogging stress. Phenotypic traits like shoot length, shoot mass and root mass were recorded. Seven cultivars/accessions (010780, 010786, LYP-73, Lasani-2008, Punjab-76, Punjab-85 and Shakar-95) did not show significant changes in root mass, shoot mass and plant height under waterlogging stress and were considered tolerant at two leaf stage. This study helped use to find cultivars which showed tolerance at germination and two leaf stage against waterlogging stress

Potassium enhanced grain zinc accumulation in wheat grown on a calcareous saline-sodic soil

Zinc (Zn) and iron (Fe) dense wheat grains are required for malnourished populations groups. Nutrient and water imbalances under calcareous saline-sodic soils decrease mineral accumulation in wheat grains. On such soils, the influence of soil potassium (K) application was studied on the accumulation of native soil and foliar-applied minerals (Zn, Fe,) in wheat grains. To field-grown wheat, two K rates were applied (0 or 35 kg ha⁻¹) at sowing in combination with four levels of foliar micronutrient sprays (control, 2×0.25% Zn w/v, 2×0.25% Fe w/v or combined Zn + Fe) at anthesis. Zinc and Fe were increased with respective micronutrient sprays. Potassium application increased grain yield, grain concentration of K and Zn in the grain. Grain Zn concentration was maximum (33 mg Zn kg⁻¹) with combined soil-applied K + foliar-applied Zn. As compared to respective foliar treatments in plots not supplied with K, grain Fe concentration was increased with soil K application in plots sprayed with Zn alone. Conclusively, optimum soil K supply increased accumulation of native soil and foliar-applied Zn in wheat grains.

Response of antioxidants and lipid peroxidation to exogenous application of alpha-tocopherol in sunflower (Helianthus annuus L.) under salt stress

Alpha-tocopherol is an antioxidant mainly responsible for detoxification of reactive oxygen species produced during prolonged abiotic stresses as reported in the previous studies. A pot experiment was carried out to study the response of antioxidants and lipid peroxidation to alpha-tocopherol seed soaking treatment in saline conditions. Seeds of sunflower cvs. FH-[572 and 621] were immersed for 16 hours in four alpha-tocopherol levels, [0 (dist. H₂O), 100, 200, 300] mg L^-1. Thirty five days after seed sowing plants were irrigated with 0 mM and 120 mM (two levels) of salt (NaCl) till final harvest. Leaves were sampled 61 days after seed sowing for biochemical analyses and yield at maturity. Salt stress (120 mM NaCl) caused significant reduction in shoot and root dry weight, total phenolic contents and superoxide dismutase activity and had non-significant effect on all yield related parameters. Salt stress showed substantial increase in the activity of enzymatic antioxidants such as catalase, peroxidase and glutathione reductase. Seed soaking with alpha-tocopherol significantly increased shoot and root dry weight, 100 achene weight and total achene weight plant^-1, catalase and peroxidase activity, total phenolic content, ascorbic acid and showed non-significant effect on leaf total soluble proteins and hydrogen peroxide. Alpha-tocopherol pre-sowing seed treatment caused significant reduction in lipid peroxidation. Cultivar FH-621 showed higher salt tolerance and alpha tocopherol 200 and 300 mg L^-1 levels effectively increased its yield and dry matter production respectively under salt stress

Grain zinc and iron enrichment through foliar application augments wheat yield under varying nitrogen regimes

Nutrients supply at optimum level is essential for the improving growth, yield and quality of wheat grain.Therefore thisstudy was carried to find the effect of Zinc (Zn), iron (Fe) and nitrogen (N) fertilization on wheat performance in field studies, during 2014-15 and 2015-16 at Cereal Crop Research Institute (CCRI), PirsabakNoweshera, Pakistan. The treatments were soil applied N (90, 120 and 150) kg ha^-1, foliar applied zinc and Fe (i.e. 1, 2, 3 kg ha^-1, each) and two controls unsprayed check (i.e. no micro nutrients, no water) and sprayed check (no micro nutrients + water). Use of 3 kg ha^-1 Zn, 1 kg ha^-1 iron and 120 kg ha^-1 Nhad significantly increased the wheat grain yield by 31% over unsprayed check. However, with increasing N to 150 kg ha^-1 in combination with 3 kg ha^-1 both Zn and Fe, the increase in grain yield was 23% over unsprayed check.  Application of 3 kg ha^-1 Zn and Fe each along with 120 kg N ha^-1 had increased the grain zinc content by 17 mg kg^-1and grain Fe concentration by 32 mg kg^-1. The grains Zn and Fe concentration were further increased to 23% and 13.4%, respectively over unsprayed checkwithincreasing N rate from 120 to150 kg ha^-1. In conclusion the higher economical wheat grain yield was achieved with 120 kg N ha^-1 along with 3 kg Zn ha^-1 and 1 kg Fe ha^-1. However, quality wheat was produced by applying Zn and Fe at 3 kg ha^-1 of each along with 150 kg ha^-1 of nitrogen. Hence, ensuring higher wheat productivity with quality grains 3 kg Zn ha^-1 and Fe each along with 120 or 150 kg N ha^-1 is recommended. 

Influence of sowing orientation and intercropping of chilies on onion yield and its associated weeds in Peshawar, Pakistan

A field trial was carried out at the Agronomy Research Farm of the The University of Agriculture Peshawar during the onion sowing season of 2015 to find out the effect of sowing orientation and intercropping chilies (Capsicum annum L.) on onion (Allium cepa L.) yield and the associated weeds. A two factorial experimental design was used for the experiment data analysis, with the experiment replicated three times. The sowing orientation was termed as Factor A with two levels i.e. North-South and East-West wards sowing, and Factor B was the intercropping treatments with five levels viz. sole onion, onion 1 row + chili 1 row (1:1), onion 1 row + chili 2 rows (1:2), onion 2 rows + chili 1 row (2:1), and onion 2 rows + chili 2 rows (2:2). Data were taken on weed density m^-2, weed fresh biomass (kg ha^-1), plant height (cm) of onion, biological yield (t ha^-1), bulbs yield of onion (t ha^-1), chili yield (t ha^-1) and Land equivalent ratio (LER). The results indicated that sowing orientation, intercropping and their interaction significantly affected the studied parameters of onion crop, intercrop and weeds. Regarding the sowing orientation, E-W sowing showed significant increase in weed density (94.27 m^-2), weed biomass (1323 kg ha^-1) and onion plant height (35.69 cm) as compared to the lower weed density (84 m^-2) and biomass (1240.67 kg ha^-1) in north-south sowing. On the other hand, the N-S sowing resulted in increased biological yield (3848.73 kg ha^-1) and bulb yield (20.73 tons ha^-1). The yield of chili was higher (6.98 t ha^-1) in North-South sowing than in east-west plots (6.20 t ha^-1). As far as the intercropping effect is concerned, maximum weed density (119.17 m^-2) and biomass (2118.5 kg) were recorded in the monocrop treatments as compared to the intercropping ones. In addition, biological (4625.84 kg) and bulb yields (23.21 kg ha^-1) were highest in sole onion plots, while intercropping with a ratio of one row of onion and two rows of the intercrop resulted in minimum weed density (48.5 m^-2), weed biomass (853.17 kg), biological yield (2430 kg ha^-1) and bulb yield (13.39 t ha^-1). The onion plant height was maximum (40.62 cm) in plots with intercropping in ratio of onion 2 rows + chili 2 rows. The chili yield was maximum (8.58 t ha^-1) in sole chili plots while minimum in the intercropping treatment of onion 2 rows + chili 2 rows (4.50 t ha^-1). It is thus inferred that sowing in the north south direction, with intercropping chili with onion in ratio of 1:1 could be a best environment friendly addition in the weed management program for yield enhancement of onion crop.

Root characteristics of individual tillers and the relationships with above-ground growth and dry matter accumulation in sugarcane

The expansion of sugarcane production areas is limited, therefore, the improvement of yield components of sugarcane might be a strategy to enhance cane production. Hence, the aim of this study was to identify the relationship between roots in each tiller and their above-ground parts during the tillering phases. This research was carried out at the Agronomy Research Station in Khon Kaen University, Thailand, using a completely randomized design with four replications. Six sugarcane cultivars, namely KK3, KPS01-12, KKU99-02, KKU99-03, UT12 and UT13, with different drought resistance levels, were assigned as treatments. Above-ground growth traits such as height and tiller number were collected at 100-175 days after planting as intervals of 15 days. Leaf dry weight, stalk dry weight and biomass were measured at 175 days after planting. Root traits, i.e. root/shoot ratio, root surface area, root length, root volume, and root number were observed at 175 days after planting. The number of roots from the main to the seventh tillers of six sugarcane cultivars followed a tiller order; all root traits were highest in the main tiller. In some cultivars, root length followed the order (from high to low) of the tiller sequence. There was a positive correlation between the sum of the roots in all tillers per hill and shoot dry weight. In terms of root traits of individual tillers, for almost all cultivars, root volume, root surface area, root length, and root number were positively correlated with biomass and stalk dry weight, except for genotype KK3. These root characteristics can potentially be used as criteria to assess shoot performance. In contrast, the root to shoot ratio may not be an appropriate characteristic to assess shoot growth, and the root dry weight varied between cultivars.

Copper bioaccumulation and translocation in forages grown in soil irrigated with sewage water

Wastewater is a source of some nutrients essential for soil fertility, but it includes various types of contaminants like heavy metals that pollute the soil and crops. In this regard, this study aimed to evaluate the possible health risks of copper (Cu) accumulation in forages irrigated with wastewater. Forages both of summer and winter were grown with different water treatments (sewage water and tap water) in the Department of Botany, University of Sargodha. The concentrations of copper in water, root and forage samples were determined. Moreover, the bioconcentration factor, pollution load index, daily intake of metals and health risk index were calculated. In tap water, the copper value was 0.072 mg L^-1 and that in sewage water 0.077 mg L^-1. In soil, the calculated copper value was lower than the USEPA standards. The maximum copper in root was determined in winter forages (0.208 mg kg^-1). The maximum bioaccumulation factor for copper was observed in Trifolium resupinatum (8.2230) grown in winter. The maximum pollution load for copper was found in Brassica campestris (0.2853) grown in winter. The maximum value for the daily intake of metals observed was 0.045, and maximum observed health risk index was 1.136.

Elemental analysis and bioactivities of Echinops echinatus Roxb. (globe thistle) via spectroscopic techniques

Echinops echinatus Roxb., belonging to family Asteraceae is traditionally used as appetizer, carminative, liver tonic, to treat jaundice, diabetes, and heart diseases. It has been reported to be a rich source of flavonoids with significant pharmacological activities. This study aimed to quantify 28 mineral elements, total phenolic and flavonoid contents, antioxidant, and anti-cholinesterase activities in its leaves, stem, flowers and achene extracts. In elemental analysis, the concentrations of Ca (9199.3 to 63975.6 µg/g) and K (7866.1 to 42700.6 µg/g) were comparatively high. Among micro elements, Sr and Zn were high in the analyzed samples. The concentrations of toxic elements were within the safe ranges established by WHO. Furthermore, ethyl acetate extract was the most enriched extract with phenolic and flavonoid contents as well as the most potent free radical scavenger (DPPH IC₅₀ 9.54 μg/mL, ABTS IC₅₀ 5.88 μg/mL). In anti-diabetic activity, leaves and stem methanol extract was the strong inhibitor of α-glucosidase enzyme with IC₅₀ values of 371.4 and 368.6 μg/mL, respectively. Methanol and ethyl acetate extracts also showed dual cholinesterase enzymes inhibition. Thus, E. echinatus could act as a potential source of natural antioxidant and does not pose any threats on consumption.

Functional analysis of Lycopene β-cyclase genes from two watermelon cultivars LSW-177 (red-flesh) and COS (pale-yellow flesh)

Carotenoid pigments are extensively found in plant tissues with multifunction. The specific carotenoids have been classified in plant photosynthetic centers and most of them are exclusively abundant in colorful fruits and vegetables. Previous results show that lycopene cyclases are fundamental for determining the proportion of carotenoids in fruit, leaves, flowers and roots. A quantitative trait locus (QTL) analysis exhibited that an enzyme is responsible for red versus non-red flesh in watermelon (Citrullus lanatus) and also correlated with the function of lycopene β-cyclase (lcyb) with flesh colour. The current study was conducted to characterize the two polymorphic genes encoding lcyb enzymes, from two watermelon cultivars (LSW-177and COS) containin the red and pale-yellow flesh, respectively. Results had confirmed the cyclase function of the two lcyb proteins in an Escherichia coli by heterologous complementation. These twolcyb proteins were differential in the amino acids at the 226^th and 435^th positions and had the effective ability to cyclase lycopene into bicyclic β-carotene, showing that these amino acid variations did not influence the functionality of lcyb enzymes in E. coli. In addition, the conversion of Ala168 to Glu168 by site-directed mutagenesis which inactivated the enzyme, suggested that this residue was part of the core region for lcyb function in watermelon. The results presented here will help more to clarify the mechanism by which lycopene β-cyclase performs its function

Evaluation of apical pinching, humic acid and plastic mulch on different characters of okra (Abelmoschus esculantus L.)

This experiment was aimed to test the effect of apical pinching, humic acid and plastic mulch on different growth parameters of okra. The results showed that pinching 2 was superior over the pinching 1 in fruit number and total yield in 2016 and 2017 seasons. Application of humic acid significantly increased all traits in two study seasons. It was also noticed that plastic mulch significantly increased all studied traits in both seasons. The interaction between pinching and humic acid were characterized by the upper values of most detected traits. The interaction between pinching 2 and clear mulch caused an increase in most characteristics in both of the study seasons. The combination treatment between humic acid at 20ml.L^-1and clear mulch had significant effect in most parameters, while the combination between 40ml.L^-1 and clear mulch gave the highest rate of nitrogen %, phosphorus % and potassium % in 2017 only. The combination among pinching, humic acid and plastic mulch significantly enhanced all studied traits in both the season (2016 and 2017).

Effect of waxing on postharvest quality and storability of ginger (Zingiber officinal Roscoe)

Desiccation remains a major limiting factor affecting the storage life of many horticultural crop species. The process of waxing, which provides a seal to protect against water loss, is currently the main method for maintaining postharvest quality of many crops. However, the effects of waxing on reducing desiccation, thereby improving postharvest quality of ginger remains unclear. This study investigates the effects of waxing on the common physiological and molecular markers of desiccation, including fresh weight loss, antioxidant system, and endogenous hormones of ginger postharvest. Results showed that both 2% and 4% wax treatments significantly inhibited rhizomes desiccation, marked by the reduced fresh weight loss and maintenance of total protein content in ginger rhizomes. Wax application significantly inhibited the rate of increase in the activities of antioxidant enzymes, including SOD, POD, and CAT, as well as lowered the concentration of MDA-each of which are required for desiccation tolerance. In addition, ABA biosynthesis and signaling were repressed by 2% and 4% wax treatments, indicating that regulation of desiccation by ABA was required. These results demonstrate that waxing of ginger rhizomes adequately reduce the rate at which desiccation may occur in horticultural crops. Therefore, the application of wax is an effective method to reduce postharvest loss of ginger rhizome

Postharvest UV-B irradiation improves the accumulation of flavonoid and biosynthetic gene expressions in Scutellaria baicalensis root

To examine the effects of postharvest UV-B radiation on the accumulation of flavonoid in Scutellaria baicalensis root and the underlying mechanism, the quantitative analysis of the flavonoid contents (baicalin, wogonoside, scutellarin, baicalein and wogonin) was performed using HPLC. The expressions of key enzyme genes PAL, 4CL, CHS, CHI, UBGAT and GUS in the biosynthesis of flavonoid were examined using RT-PCR. The value of flavonoids, especially baicalin, wogonoside and wogonin, displayed a time-dependent increase, and the content of baicalin in the control reached 80.7 mg/g at 12 h during drying process. The content of baicalin in UV-B treatment was increased significantly by 69.67% (p<0.05) and 51.32% (p<0.05) respectively compared with control at 12 h (109.14 mg/g) and 24 h (97.35 mg/g) and reach the maximum value at 24 h. The key enzymes exhibited different expression patterns during the postharvest drying process. The mRNA levels of key enzyme genes CHS, CHI, GUS and PAL in the control were observed to be stimulated, reaching peak levels at 12 h, and their maximum value reached 3-, 3-, 4-, 5- and 4-fold of that at 0 h respectively. While they exhibited an even more increase in UV-B irradiation treatment compared to the control. Appropriate water deficit in dehydration could significantly promote the levels of flavonoids in S. baicalensis roots and suitable concentration of UV-B treatment is an effective approach for promoting the content of flavonoids during the postharvest drying process

Chemical composition, ruminal degradation kinetics and methane production (in vitro) potential of local and exotic grass species grown in Peshawar

Livestock production, and small scale and extensive grazing livestock production systems in Pakistan lack long-term sustainability due to declining quantity and quality of green forages and pastures. Information on the nutritional value of range/pasture and cultivated grass species is required to design proper strategies not only for nutritional management of grazing animals, but also for development of good quality forage resources. Therefore, the current study was planned to: (i) analyze the chemical profile of traditional and novel grasses grown in Peshawar; (ii) quantify the methane emission potential of the grass species; and (iii) quantify the differences among species in their nutritive value and methane emission. Ten grass species, namely, Sudex (Sorghum × sudangrass), Jumbo grass (Sorghum bicolour× Sorghum sudanefe), Sorghum almum, Pennisetum purpureum, Vetiveria zizanioides, Panicum colaratum, Cynodon dactylon, Bothriochloa pertusa, Splenda setaria and Desmostachya bipinnata were evaluated under uniform agronomic and environmental conditions. The results showed that the contents of all measured chemical components, mineral profile (except Zn), In vitro digestibility of dry matter (DMD), and In vitro gas (GP) and methane-production had large variation among the grass species. Among the grasses, Jumbo grass had greater CP (11.9% DM) content and In vitro DMD (65.9% DM), and produced greater amount of total gas, that contained lowest proportion of methane. In contrast, D. bipinnata had lowest contents of CP (6.3% DM) and In vitro DMD (43.7% DM), and produced lower amount of total gas, with highest proportion methane in total GP. Next to D. bipinnata, V. zizanioides had lower degradability/GP and highest proportion of methane in total gas. The large variation in chemical composition, DMD and methane-emission potential of the summer grass species presents a prospect to select and further develop grass species that have lower methane-emission potential and high nutritional value. Further research is needed to investigate the changes in chemical profile, DMD and methane-emission of forage species between seasons and with maturity

Calcium effects on post-harvest attributes and vase life of gladiolus using different methods of application

Gladiolus can play a key role in generating substantial amount of revenue in cut flower trade, however, the rapid loss of quality is a serious threat to its wider adaptation as a commercial crop. Hence both pre and post-harvest management is pre-requisite to extend the vase life of gladiolus. For this purpose, the present study was conducted to determine the influence of calcium concentrations i.e., Distilled water & tap water (Double control), 100, 200, 300 and 400 mM and application methods (holding solution in vase and foliar spray) on post-harvest attributes and vase life of gladiolus spikes in post-harvest Laboratory during the years 2016-2017. The findings of the study revealed that calcium concentrations and application methods had significant effects on all studied traits of gladiolus. Calcium at 200 mM and vase holding solution resulted in extended 1^st floret and full spike fading. Likewise, the higher fresh floret weight  and senesced floret weight , retention of highest reducing  and non-reducing sugars, least electrolyte leakage  and extended vase life of gladiolus spikes  was also observed at 200 mM calcium concentration and in vase holding solution. The least loss of protein and highest total phenols was also recorded in florets of gladiolus spikes kept in holding solution of 200 mM calcium. It is concluded that application of 200 mM calcium through holding solution was most effective in retaining the quality of gladiolus florets and spikes over extended period and enhanced the vase life of gladiolus spikes.

Analysis of genetic diversity in purple lettuce (Lactuca sativa L.) by SSR markers

In this study, we analysed the genetic diversity and relationships of the leaf lettuce germplasm by SSR markers. The HPLC and Colorimeter techniques were used to measure the anthocyanin contents and colour indices of 54 different coloured Lactuca cultivars. Five colour levels of lettuce can be established for leaf grading by our correlation analysis between the colour parameters and contents of anthocyanin. The purple part in the distribution of lettuce leaves can be classified into four categories. This study provides a measure of the leaf colour traits using the scientific method. We also analysed the genetic diversity and relationship among 39 purple leaf lettuce germplasms by SSR markers. Our findings showed that the average values of Nei’s gene diversity and Shannon’s information index for the 39 cultivars were 0.5635 and 1.0151, indicating a low degree of genetic diversity among the tested genotypes. Cluster analysis showed that all 39 varieties were clustered into two major groups with a similar coefficient of 1.2125. The group I was divided into two sub-groups: leaf fold lettuce and erect lettuce. The first sub-group of lettuce leaf colour was purple, and the anthocyanin contents were greater than those in the other sub-group Crisphead lettuce. The group II was further divided in two sub-groups: leaf fold lettuce and erect lettuce. There were three species in the same branch with a close genetic relationship. The 39 purple leaf lettuce varieties with different SSR fingerprints could serve as cultivar-specific patterns and as an important basis for varieties identification.

Studies on genetic divergence of rapeseed genotypes using SSR markers

Thirty five Brassica napus genotypes were evaluated to check their genetic diversity on the basis of mapped 20 microsatellite markers. The genetic similarity values of coefficient ranged from 0.28 to 0.85. A dendrogram was generated based on UPGMA which showed that genotypes were divided into five major clusters. Cluster A had genotypes with higher similarity coefficient of 0.85 while Cluster E had only one genotype (pop 35) genetically distinct from other genotypes. PIC values were calculated for each of the 20 SSR primer pairs. Ten primers PIC value ranged from 0.30 (O110-A05) to 0.59 (Na10-D09 markers). This study would be helpful in assessing the genetic diversity. It was revealed that there was no correlation between the geographical distribution and genetic diversity of the studied germplasm, depicting their close genetic relationship. 

DNA barcoding and molecular systematics of selected species of family Acanthaceae

In the present study the phylogeny of the various selected genera of Acanthaceae was investigated based on macro-morphological characters, chloroplast DNA (cp-DNA) genes rbcL, matK and intergenic spacer trnH-psbA sequences. About 34 macro-morphological characters of taxonomic importance were selected from the different floras of the world which were used to construct a phylogeny based on morphology. For morphological analysis selected species belonging to five different genera of Acanthaceae including Ruellia, Justicia, Barleria, Dicliptera and Strobilanthes were studied. The phylogenetic tree was constructed using Multivariate Statistical Package (MVSP 3.1) by the method of UPGMA (Unweighted Pair Group Method Analysis). Our results showed that Ruellia brittoniana seemed to be the closest relative of Justicia and Barleria species based on morphological analysis. The plastid gene regions ribulose-1,5-bisphosphatecarboxylase/oxygenase (rbcL), maturase kinase (matK) and trnH–psbA intergenic spacer region were selected for taxonomic study on molecular level. These genes rbcL (1400 bp), matK (800 bp) and trnH–psbA spacer (400 bp) were sequenced and the sequence data was aligned and used for the phylogenetic tree in combination with the other sequences retrieved from GenBank, National Centre of Biotechnology Information (NCBI). Molecular data based on these matK, rbcL and trnH–psbA sequences and the BLAST result shows that genera Barleria, Strobilanthes and Ruellia are monophyletic but genus Justicia is non-monophyletic. Our results conclude that rbcL is more effective barcode; while combination of matK and trnH–psbA can be used for identification and phylogenetic study of plants

Paternity analysis and SNP development for Osmanthus fragrans ‘pucheng dangui’ using SLAF-SEQ

Osmanthus fragrans ‘Pucheng Dangui’ is a new ornamental and urban-greening plant variety developed through long-term natural and artificial selection. Urban and rural horticultural industries in Pucheng County, Fujian Province, China, have developed rapidly and many nurseries now grow O. fragrans ‘Pucheng Dangui’ by cuttings. We developed a paternity test and SNP markers for O. fragrans ‘Pucheng Dangui’ using SLAF-seq to identify the fine variety O. fragrans ‘Pucheng Dangui’ based on molecular research. The genome sequence of Fraxinus excelsior was used as the reference to predict restriction enzyme digestion for O. fragrans ‘Pucheng Dangui’. Restriction enzyme digestion fragments between 400 and 480 bp length were defined as SLAF tags digested by the enzyme Hpy166II+EcoRV-HF^®. A total of 413,743 SLAF tags was identified, of which 113,061 polymorphic SLAF tags and 353,073 population SNPs were derived. Analysis of the phylogenetic tree, the population admixture structure, the admixture K value cross validation error rate, and the PCA clustering figure showed that all 29 plant samples belonged to the same population, with no significant differences detected between samples. This comprehensive analysis of DNA polymorphisms provided valuable insights into the different individuals or populations of O. fragrans ‘Pucheng Dangui’ and it provided producers and vendors with confidence in the source of their plant material. This results provides a reliable method for researchers to identify O. fragrans ‘Pucheng Dangui’ from other O. fragransspecies or varieties by the molecular approach. The identification of intraspecific genetic variations also provides the basis for further development of individual plant analysis, identification and introgression breeding in other species.

Protein isolation and identification of trichosanthes kirilowii seed from different places of production

In this paper, 12 samples of Trichosanthes kirilowii seed from different places of production were studied. The total proteins of the 12 samples were extracted by Tris-phenol method. Twelve samples of proteins were isolated by SDS-PAGE. SDS-PAGE results showed that the protein bands in sample No.8 are different from those of other samples. And those protein bands were identified by mass spectrometry. At least 10 differentially expressed proteins were identified, including rRNA N-glycosidase, Acetyl-CoA acyltransferase, Citrate synthase, Phosphoglycerate kinase, Isocitrate dehydrogenase, Fructose-bisphosphate aldolase, Ferritin, Urease, Hhydroxyacyl-ACP-dehydratase, Glutathione peroxidase. From the result of protein identification, it can be inferred that the seed of No. 8 sample was superior to other samples during germination

New fragrance allele according to insertion/deletion in non-coding DNA sequence of the Fragrance gene found in Asian cultivated rice (Oryza sativa L.), wild and weedy relatives from Indochina

Fragrance is one of the most important trait in cultivated rice. The fragrant allele in rice germplasm worldwide was investigated continuously. The purpose of this study was to investigate variation in non-coding sequences of the fragrance (fgr) gene in cultivated rice and its relatives from Indochina (Thailand, Laos and Cambodia) using PCR and re-sequencing techniques. Two new additional insertion/deletion were observed in intron 6 of the fgr gene in fragrant cultivated rice and its relatives from Thailand compared to fragrant and non-fragrant cultivated rice accessions from Myanmar, China and Japan. This finding may shed light on a wide range of genetic resources of rice available for aroma trait in breeding program and on the evolutionary process underlying differentiation of rice cultivars from progenitor lineage.

Comparative performance of CGR₃ and CGR_3-1 on photosynthetic characteristics and yield of mung bean (Phaseolus radiata)

The effects of methyl 1-(3, 3-dimenthyl-2-oxobutyl)-1H-1, 2, 4-triazole-3-carboxylate (CGR₃) and 1-(3,3-dimethyl-2-oxobutyl)-1H-1, 2, 4-triazole-3-carboxylic acid (CGR_3-1), as two new plant growth regulators, on photosynthetic characteristics and mung bean yield were investigated in this study. Both regulators improved the net photosynthetic rate (P_N), stomatal conductance (gs), intercellular CO₂ concentration (Ci) and transpiration rate (E); CGR_3-1 had a larger impact than CGR₃. In terms of photosynthetic efficiency, CGR_3-1 showed higher effectiveness. Considering photosynthetic pigments, the two regulators enhanced the contents of chlorophyll a, chlorophyll b, chlorophyll (a+b) and carotenoid. The application of CGR_3-1 (CGR₃) significantly increased (decreased) the contents of soluble sugar and starch. The results indicated that CGR_3-1 was more effective in improving the photosynthetic characteristics and yield of mung bean and can be a widely adopted strategy for producers

Seasonal variation in lycopene and β-carotene content in Momordica cochinchinensis (Lour.) Spreng. (Gac fruit) genotypes

Gac fruit (Momordica cochinchinensis (Lour.) Spreng.) is a good source of lycopene and β-carotene, and it has high potential to be used as functional food. However, phytochemicals could be affected by seasonal variations. The objective of this study was to evaluate seasonal variations in lycopene content, beta-carotene content and agronomic traits in Gac fruit. Three Gac fruit genotypes were arranged in RCBD with three replications and harvested over three seasons. Lycopene and β-carotene content were analyzed by HPLC. The season significantly affected concentrations of lycopene, β-carotene and total carotenoids in Gac fruits. KKU ac.10-087 and KKU ac.09-030 had the highest lycopene in the summer season whilst KKU ac.10-087 also had the highest lycopene in the dry season. Seasonal and genotypic variations were important sources of variations in lycopene, β-carotene and total carotenoids in Gac fruits

L-asparaginase, acrylamide quenching enzyme production from leaves of Tamarindus indica and seeds of Vigna radiata–Fabaceae

Current study aims at high yield production of L-Asparaginase from family fabaceae. Leaves of Tamarindus indica, seeds of Vicia faba, Phaseolus vulgaris, Pisum sativum, Cicer arientinum, Vigna radiata are screened for l-Asparaginase yield and activity. Prepared crude extracts are purified through ammonium sulfate precipitation, dialysis, ion exchange chromatography and gel filtration. When incubated with l-Asparagine, crude extracts of Pisum sativum leaves and seeds of Cicer arientinum, Phaseolus vulgaris and Vicia faba extracts showed 24.93 U/mL, 10.38 U/mL, 11.81U/mL enzymatic activity, respectively. Crude extract of Tamarindus indica leaves exhibited highest enzyme activity of 64.38 U/mL, with a yield of 67% while Vigna radiata seeds crude extract revealed 53% yield with enzymatic activity of 56.34 U/mL.l-Asparaginase enzyme purified from Tamarindus indica has activity of 54.260±0.847 U/mL with specific activity of 95.67 U/mg. l-Asparaginase purified from Vigna radiata seeds exhibit 45.140±0.302 U/mL activity and specific activity 135.25 U/mg. The purified enzyme exhibits maximal activity at 37℃, stability at optimal pH 8.6 in the presence of alkaline 0.2 M potassium phosphate buffer. Optimal substrate concentration for l-Asparaginase activity is 3.5 ug/mL from Tamarindus indica. Results shows that Vigna radiata and Tamarindus indica can be a better choice as high source of l-Asparaginase that can be employed to reduce acrylamide cancer provoking element in food industry

Osyris (Osyris alba L.) updates, the illustrated threatening parasite to fruit and forestry trees in Jordan

Field trips carried out in different parts of Jordan showed that Osyris alba L. is parasitizing certain fruit and forestry species of different plant families. The parasite was found attached to the root system of olive, grape, almond, figs and plum, and on forestry trees of cypress, orange wattle, Aleppo pine, Palestine buckthorn and wild pistachio. In addition, different common wild shrubs including the widely spread thorny burnet and spiny broom were severely attacked. The parasite growth mass was different on different hosts. Cypress, olive, almond and grapes were heavily attacked while Aleppo pine showed low infestation. O. alba may exhibit host preference, since it caused death to several fruit and forest species including olive in certain sites. Farmers indicated that birds and mainly the yellow vented bulbul, commonly found in different places, is the main dispersing agent of parasite seeds since it feeds on the abundantly produced berry fruits. The infected hosts and the parasite were photographed and illustrated. In conclusion, the parasite is spreading on economic fruit and forestry species and has the potential to spread into other geographical regions. The heavily attacked thorny burnet and spiny broom may be regarded as a source of parasite infestation since common in different regions. The parasite may be considered as a serious threat to important tree species in the country.

Comparitive phytochemical and physicochemical study of seeds of the genus Angelica L. from Neelum valley Azad Kashmir, Pakistan

Seeds of Angelica species Angelica glauca Edgew. and Angelica archangelica var himalaica (Clarke) E. Nasir family Umbelliferae were collected for phytochemical and physico-chemical study. Seeds and other parts of the Angelica species are used to cure in variety of ailments in many countries.  Seeds of two species of the Angelica were analyzed for the detection of bioactive compounds by using acetone, chloroform, methanol and water extracts. Maximum solubility of seeds extract of both species was high in water solvent while acetone and chloroform were not ideal solvents for extraction while methanol was a moderate solvent. Chemically the seeds of both Angelica species showed variety of bioactive compounds including alkaloids, phenolic compounds and flavonoids thus, seeds can be used for medicinal purposes after ascertaining their pharmacological activity.

Growth pattern of Pinus roxburghii under different regimes of invasive species in Panchase, Nepal Himalayas

Invasive alien species have taken attention as one of the significant threats to biodiversity worldwide. The ongoing climate change is likely to exaggerate the problem by opening up favorable environment Invasive alien species have taken attention as one of the significant threats to biodiversity worldwide. The ongoing climate change is likely to exacerbate the problem by opening up favorable environments for invasion, putting the ecological, environmental and socio-economic state into stake. The assessment of potential impacts of invasive species on native species is crucial for prevention and mitigation measures. Thus, the current study aimed to assess the impact of invasive species (i.e., Ageratina adenophora Sprengel) on the growth of ecologically important native tree species (i.e., Pinus roxburghii Sargent) in Panchase, Nepal Himalaya. Furthermore, it explored the dendroecological approach of Pinus roxburghii to assess the potential impacts of invasive species on its growth. The growth pattern was focused on regeneration, tree radial growth and inter-nodal growth rate of saplings and seedlings of Pinus roxburghii under two different classes of invasion i.e., low and high-density. The study revealed that the density and inter-nodal growth rate of seedlings of Pinus roxburghii declined significantly whereas no significant decline occurred in its saplings with the increase in invasion. However, the saplings showed significant increment in its inter-nodal growth rate with the increase in invasion. In the case of its tree, no such significant impact in the radial growth rate was observed. The novel study using dendroecological approach revealed that the invasive species have differential impacts on the growth of nearby native tree species with higher impacts during the seedling stage compared to the saplings and tree stage. 

Spatial distribution characteristics of lichens in forest of Dabie mountain, Anhui province, China

Twenty-nine lichen quadrats were sampled in Yaoluoping national nature reserve. The data of three environmental factors, relative humidity, altitude and illumination, were collected. According to RDA results, the eigenvalue of canonical axis 1 and canonical axis 2 were 0.123 and 0.068, respectively, accounting for 82.9% of total eigenvalue of the first four axes. The first canonical axis mainly reported the change of environment variable humidity. Peltigera neopolydactyla had the highest positive correlation with humidity where as Leptogium saturninum and Cladonia chlorophaea had the highest positive correlation with altitude factor and illumination factor respectively. Spearman rank correlation coefficient test showed no significant negative correlation species-pairs (p<0.05). Fifty one species-pairs showed positive correlation ship. The distribution pattern is comprehensive response to environmental factors, of which environmental humidity, exactly availability moisture of lichens, has the greatest influence on it. Twenty-nine quadrats could be divided into six associations based on three environmental factors. There were no significant negative correlation species-pairs in the lichens, which might be due to small lichen individual, sparse distributing pattern and low interspecific competition (p<0.05). The bonding intensity of lichen interspecific relation-ship is a comprehensive response to available moisture and the type of substrates. 

Phytogeographic classification using multivariate approach; a case study from the Jambil valley Swat, Pakistan

Phytogeography is concerned with the past and present distribution of vegetation on the earth surface. The distribution of plants is neither even nor random on earth surface but follow a definite geographic pattern. The present study was aimed to find out phytogeographic pattern of plants distribution and subsequent classification of plant species of the Jambil Valley, District Swat Pakistan using multivariate statistic techniques. Sampling of vegetation was done using quadrats of 1 × 1 m² for herbs, 5 × 5 m² for shrubs and 10 × 10 m² for trees. The data were analyzed by PCORD v. 5 and CANOCO 4.5. The studies revealed that the vegetation of Jambil valley belongs to eighteen different phytogeographic elements. The highest percentage of elements (19.4%) belongs to Western-Himalayan region, followed by Cosmopolitan (13.9%), Eurasian (10.6%), Irano-turanian (10%), Paleotropical (9.4%), Eastern Asiatic and Mediterranean (6.7% each), Euro-Siberian (5.6%), Holoarctic (3.9%), Pantropical (3.3%), Sub-cosmopolitan (2.8%), Saharo-Arabian (2.2%), Eastern-Himalayan (1.7%), Central Asian and Neotropical (1.1% each), Pantemperate, Australian and Sudano-Zambezian (0.6% each). CANOCO correlated phytogeographical data with environmental factors, which showed significant effect of environmental variables on phytogeographical patterns. It is clear from our results that higher pH, electrical conductivity, moderate sand and silt, phosphorous and nitrogen have great impact on distribution of phytogeographical elements. The Western Himalayan elements having narrow geographic range require immediate attention and conservation efforts.

Hoya lamthanhiae (Asclepidoideae, Apocynaceae), a new species from southern Vietnam

Hoya lamthanhiae V.T. Pham & Kloppenb. is described and illustrated. The molecular data is provided; this species was found in Dak Lak province, southern Vietnam. Diagnostic features of the new species are a milky latex lithophytic vine and pure white with red-purple centre flowers. The described species clearly differs from closely related H. hainanensis in number of characters: a leaf blade shortly attenuated and wavy margins at the base, a hairy abaxial leaf surface, a bigger calyx with few sparse hairs or glabrous, a bigger corolla with acute lobe, shorter pollinia, as well as molecular characters

Morphology, anatomy and palynology of two endemic Cousinia cass. species (Sect. cousinia, Asteraceae) and their taxonomic implications

The morphological, anatomical and palynological features of Cousinia eleonorae Hub.-Mor. and Cousinia humilis Boiss. are provided along with their taxonomic significance. Their expanded description, distribution map and coloured photographs are also given. The morphological characteristics of leaves, phyllaries are taxonomically significant for distinguishing Cousinia species. In addition, the micromorphological characteristics of pollen grains and achenes are provided with the use of scanning electron microscopy. Anatomical characters such as number of cortex cells, number of vascular bundles and midrib shape are found to be significant characters. Moreover, exine sculpturing pattern and shape of pollen grains can be used for taxonomic purposes.

Studies on pollen storage and vitality difference of tea plant varieties

Pollen vitality of four different tea plant varieties under different storage conditions were tested by vitro germination method. Results demonstrate that storage temperature and drying processing can influence pollen vitality significantly. Low-temperature dry environment is in favor of pollen vitality maintaining. Pollen samples which are processed by drying agent under room temperature, 4℃ and -20℃ can maintain vitality for 7 days, 20~30 days and 30~40 days, respectively. Pollen sample which haven’t processed by dry agent under room temperature, 4℃ and -20℃ can maintain vitality for 1~3 days, 10 days and 20~30 days, respectively. Different tea plant varieties have different pollen storage capacities. Among four testing varieties, Foxiang 3# loses pollen vitality the most quickly, while the Yabukita presents strong pollen storage capacity under all treatments.

Enzymatic hydrolysis of Saccharum officinarum Lignocellulosic biomass by genetically modified hyperthermophilic cellulases

The rapid exhaustion of fossil fuels and increasing environmental pollution due to burning of traditional fuels urge the scientists to look for alternative renewable energy resources. One of the important renewable energy sources is bioethanol. Bioethanol production from lignocellulosic substrate comprises of different steps. One of the important part of these steps is saccharification which yield fermentable sugars that can later be converted into ethanol by fermentation. In the present study, hyperthermophilic cellulolytic enzymes (Endoglucanase, Exoglucanase and β-Glucosidase) produced in genetically modified mesophilic host Escherichia coli BL-21 strain were used for hydrolysis of untreated and pretreated sugarcane bagasse samples. Alkaline peroxide treated bagasse was screened among differently pretreated sugarcane bagasse samples and saccharification yield of 26.64% was achieved by simultaneously adding 150 Units of Endo-1,4-β-glucanase, 300 Units of Exo-1,4-β-glucanase and 600 Units of β-1,4- Glucosidase for 3h at 80°C. Moreover, substrate concentration of 0.75% (w/v) yielded best hydrolysis rate of 35.19%. This optimization study resulted in 8.05 folds increase in the saccahrification yield which is an important step forward towards cheap production of fermentable saccharides.

The correlation between eco-restoring modes and soil quality succession during plant re-vegetation in large-scale mining areas

By using the fixed monitoring sample sites of two re-vegetation modes in the opencast coal mine dump of Zhongmei Pingsuo as platform, we analyzed the number and the dynamic characteristics of the spatial distribution of all naturally re-generated seedlings in 2010 and 2014, sampled the corresponding soil, and investigated the correlation of two re-vegetation modes and soil quality parameters. Our results indicated that (1) the plant vegetation seedlings of SII site reduced and those of SI site significantly increased, which was opposite to saplings, and in 2014, the number of saplings in SII site substantially increased twice than the number in 2010; (2) from the respective of spatial distribution, the spatial map of seedlings and saplings showed that the their distribution of major species was consistent in 2010 and 2014. The dense and sparse areas in 2010 kept a similar distribution in 2014, which corresponds to the quantity of the species; (3) stepwise linear regression analysis between the survival rates of seedlings and saplings of various species and soil parameters indicated that the survival rate of elm seedlings significantly negatively correlated with soil moisture content and positively correlated with pH, and that the survival rate of locust saplings exhibited an extremely positive correlation to the organic matter content.

Production of cellulase and xylanase from Candida tropicalis (MK-118) on purified and crude substrates

Lignocellulose, a mixture of cellulose, hemicellulose and lignin, is naturally occurring chemical feedstock on earth which can serve as substrate for the production of plant cell wall degrading enzymes (PCWDE) including cellulase and xylanase. Yeast strains have scarcely been reported for the simultaneous production of more than one PCWDEs. In this study, an indigenous strain of Candida tropicalis MK-118 has been reported for the potential to co-produce endoglucanase (EG), β-glucosidase (BGL) and xylanase (Xyl). It was observed that the production of an individual enzyme varied differently with a change in cultivation conditions. For EG and BGL production, cultivation at 40^oC was more suitable while the highest titers of Xyl were obtained at 25^oC. Higher yields of EG and Xyl were obtained under neutral pH, whereas, acidic medium favored BGL production. Although, an inoculum size of 2% was found appropriate for all the three enzymes, however, maximum production of EG, BGL and Xyl was obtained in presence of 0.5% carboxymethyl cellulose, 1.5% salicin and 1% xylan. Furthermore, the enzymes were characterized for their optimal activities. The strain showed ability to ferment sugarcane-baggase and wheat-bran with the concomitant production of cellulases and xylanases. Interestingly, the strain also produced alcohol in complex medium. C. tropicalis MK-118 may find its application for the production of industrially important enzymes and alcohol under submerged fermentation of crude substrates. The properties of enzyme preparation were industrially relevant and hence the enzyme can also be applied for various processes

Glucoamylase from a thermophilic strain of Bacillus licheniformis RT-17: production and characterization

Glucoamylase is an industrially important enzyme that finds many applications including in the production of glucose and fructose syrups. Commercially it is obtained from the species of Aspergillus and Bacillus. Bacillus being source of thermostable enzymes has been studied widely for the prospects of getting proteins having industrially relevant properties. In the present study, a thermophilic strain of Bacillus licheniformis RT-17 was investigated for its ability to produce glucoamylase. After initial experiments, the factors affecting glucoamylase production were screened using Plackett-Burman design (PBD). The data indicated that out of six factors, one factor i.e. incubation period was found having significant effect on the response and hence was studied separately. The strain produced the maximum titers (0.017 IU mL^-1) after 24 h of incubation, the production dropped significantly if cultivation is extended to 48 or 72 h that could be linked with the proteolytic potential of this strain. The enzyme in cell-free culture supernatant was partially purified by 1.3 fold with 65% yield using 80% ammonium sulphate.  The partially purified enzyme was characterized for its temperature and pH optima. The results showed that glucoamylase from RT-17 performed optimally at 50^oC under alkaline conditions (pH 8.2) in presence of 1.8% starch. Thermophilic nature of the strain, heat- and alkali-stability of the glucoamylase indicate possible candidature of the strain for future biotechnological applications.

Primary  investigation  of  the diversity  and  distribution characteristics of Trichoderma spp. in the specific soil of volcanic forest park and volcano platform

Trichoderma spp. are used in biological plant protection as biofungicides as well as in bioremediation. Trichodrma spp. are also utilized as bio-fertilizer to improve and amend soil. To obtain more optimized germplasm resources of Trichodrma spp., the diversity and distribution of Trichoderma species were investigated and explored in the Volcanic Forest Park and volcanic platform in Heilongjiang Province, China. Twenty-eight soil samples near the root, including the rhizosphere of different plants were collected. The Trichoderma strains were screened by dilution plate method. Species were identified through morphological characteristics, analyses of Internal Transcribed Spacer (ITS) sequences and genetic relationships based on phylogenetic tree. As a result, a total of 201 Trichoderma strains were isolated from the two sampling spots and they were identified to be members of 13 known species of Trichoderma, including T. harzianum, T. hamatum, T. atroviride, T. citrinoviride, T. virens, T. koningii, T. koningiopsis, T. viride, T. tomentosum, T. petersenii, H. stellate, T. saturnisporum and T. asperellum. Among all the identified species, T. harzianum was the dominant species, accounting for 43.28% of the total, followed by T. viride, which accounted for 14.93%. 12 species were obtained from the soil of the Volcanic Forest Park, while 8 species were acquired from the volcanic platform, which showed the difference of species diversity of Trichoderma between the two spots. In addition, there were differences in Trichoderma species and stains according to the differences of plants at each sampling spot. In short, our results would illustrate the elementary diversity and distribution characteristics of Trichoderma spp. in the two specific types of soil and provide novel germplasm resources for improved mixed Trichoderma bio-fertilizer.

Screening of plant growth promoting rhizobacteria for sustainable wheat (Triticum aestivum L.) crop production

The study was conducted to isolate and characterize wheat plant growth promoting rhizobacteria (PGPR). The isolation was carried out at tillering stage of wheat crop. The potential of wheat for colonizing different microbes at different combinations of organic and inorganic nutrient sources was determined. Overall, the microbes were more abundant in rhizosphere as compared to non-rhizosphere soil. The highest population of bacteria 9.64 log (cfu g^-1 soil) and N₂ fixing bacteria 7.67 log (cfu g^-1 soil) were found in the rhizosphere of wheat where 50 kg N and 33 kg P₂O₅ ha^-1 integrated with FYM 9 t ha^-1. However, the most phosphate solubilizing bacteria 9.08 log (cfu g^-1 soil) was recorded at sole application of FYM (9 t ha^-1). A total of 24 potential isolates varying in colony morphology were screened for further characterization. Most of the PGPR exhibited the capability of nitrogen fixation, P solubilization and IAA production. The P solubilization efficiency ranged from 11.14 to 75.00% with the highest recorded in NIA-PGPR1 (75%). The screened isolates produced indole-3 acetic acid (0.88-8.92 mg L^-1) with the highest IAA production of 8.92 mg L^-1 in NIA-PGPR9. All PGPR strains also had the abilities of biofilm formation. Ten (10) most efficient PGPR isolates were selected for evaluation in enhancing wheat growth under laboratory conditions. All inoculated PGPR isolates positively affected wheat plant growth. The highest plant height (31.5 cm) was observed in plants inoculated with NIA-PGPR1 while maximum root length (8.5 cm) and plant dry biomass (0.172 g) was recorded in NIA-PGPR5. The screened bacterial strains have plant beneficial characters and have potential for development of bio-product in order to enhance wheat plant growth in a sustainable manner