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Salinity stress effect crops in various ways, leading from abnormalities in gene expression via changes at the cellular level to alterations in growth and development of the crop. Salinity greatly affects the crop productivity by inducing various complications in plants. In the current study, we have screened 69 soybean cultivars on the basis of their salinity resistance by devising an easy, rapid, reliable, and inexpensive screening technique. The growth, biomass and physiological parameters of the selected cultivars were measured after growing them for 42 days in hydroponic solution. The variations among the cultivars through selected parameters of the control and stressed plants were assessed to group the cultivars in three groups, i.e. highly susceptible (HS), susceptible (S), and tolerant (T). Certainly, the application of NaCl as a salt stress has significantly affected the root and shoot length, transpiration rate (TR), photosynthesis, chlorophyll contents, root and shoot weight, nodule weight in most of the soybean cultivars. Besides, few cultivars have retained the above mentioned growth parameters under the salinity stress conditions due to tolerance against saline conditions. Based upon the overall performance, 10 cultivars were found to be tolerant, 3 cultivars were susceptible and 56 cultivars were highly susceptible to salinity stress among the 69 tested cultivars of soybean. [ABSTRACT FROM AUTHOR]

We have isolated an endophytic fungus with heat stress alleviation potential from wild plant Euphorbia indica L. The phylogenetic analysis and 18S rDNA sequence homology revealed that the designated isolate was Aspergillus japonicus EuR-26. Analysis of A. japonicus culture filtrate displayed higher concentrations of salicylic acid (SA), indoleacetic acid (IAA), flavonoids, and phenolics. Furthermore, A. japonicus association with soybean and sunflower had improved plant biomass and other growth features under high temperature stress (40°C) in comparison to endophyte-free plants. In fact, endophytic association mitigated heat stress by negotiating the activities of abscisic acid, catalase, and ascorbic acid oxidase in both soybean and sunflower. The nutritional quality (phenolic, flavonoids, soluble sugars, proteins, and lipids) of the A. japonicus-associated seedlings has also improved under heat stress in comparison to endophyte-free plants. From the results, it is concluded that A. japonicus can modulate host plants growth under heat stress and can be used as thermal stress alleviator in arid and semiarid regions of the globe (where mean summer temperature exceeds 40°C) to sustain agriculture. [ABSTRACT FROM AUTHOR]

Crop productivity continues to decline due to a wide array of biotic and abiotic stresses. Salinity is one of the worst abiotic stresses, as it causes huge losses to crop yield each year. Kinetin (Kn) has been reported as plant growth regulator since long, but its role in improving plant growth and food quality under saline conditions through mediating phytohormonal cross-talk is poorly studied. Current study was designed to evaluate the impact of exogenously applied Kn on growth, isoflovones and endogenous phytohormones of soybean grown under NaCl induced salt stress. Soybean plants were grown in perlite (semi hydroponic), and under controlled green-house conditions. Elevated levels of exogenous Kn significantly mitigated the adverse effect of NaCl and rescued plant growth attributes, i.e., plant height, fresh and dry biomass of soybean plants grown in all treatments. Higher diadzen, glycitin, and genistin contents were observed in plants treated with elevated Kn in the presence or absence of NaCl induce salt stress. The gibberellins (GAs) biosynthesis pathway was up-regulated by Kn as the bioactive GA1 and GA4 contents were significantly higher in Kn treated plants, as compared to control, while GAs level reduced in NaCl treated plants. Contrary to GAs, the abscisic acid contents declined with Kn but promoted in NaCl stressed soybean plants. The endogenous jasmonic acid and salicylic acid contents of soybean enhanced with elevated Kn application, but they showed an antagonistic response under salt stress. Current study supports the active role of Kn to ameliorate the adverse effects of salt stress on the growth and food quality of soybean. The favorable role of Kn toward soybean growth under salt stress may be attributed to its potential to modulate crosstalk between the various phytohormones involved in soybean growth and its resistance to salinity stress. [ABSTRACT FROM AUTHOR]

Most of the plant species are susceptible to various ecological constraints, including high temperature stress. Endophytic fungi can defend the host crops from the extreme effects of thermal stress. We isolated fungal endophytes from a wild plant species Sonchus asper L. to study its effect on the physicochemical characteristics of Helianthus annuus L. and Glycine max L. exposed to high temperature stress. Biochemical and physiological parameters, such as chlorophyll contents, total biomass and height of the Helianthus annuus and Glycine max were promoted, whereas the production of ROS (Reactive Oxygen Species) and lipid peroxidation were inhibited in the fungal inoculated plants. Furthermore, higher amounts of ROS-degrading antioxidants [CAT (catalase), SOD (superoxide dismutase), POD (peroxidase), GR (glutathione-reductase) and AAO (ascorbic acid oxidase)], sugars, proteins, lipids and phenolics were noted in host crops. Lower concentration of proline and ABA on the other hand was observed in plants inoculated with fungal strain and exposed to heat stress. The potent strain was found to be Stemphylium solani after amplification of the ITS region of 18 S rDNA. The results concluded that S. solani can be handy in mitigating heat stress in food crops. [ABSTRACT FROM AUTHOR]