Endophytic Aspergillus Fumigatus sp. LH02, isolated from the roots of soybean and indentified through phylogenetic analysis of 18S rDNA sequence, was found stimulatory to the growth of Waito-C rice seedlings among 13 other endophytic strains screened. In growth hormone analysis, pure culture of fungal isolate produced three gibberellins viz GA4, GA9 and GA12. To know the role and effect on soybean in endophytic association (EA) and non-endophytic association (NEA) under salt stress (70 and 140mM), experiment was carried out at growth chamber using complete randomized block design. The results elaborated that the EA has significantly increased the shoot length, shoot and root fresh and dry weights, chlorophyll content, photosynthesis rate and leaf area of the plants with and without salt stress compared to control. Field emission scanning electron microscope analysis of root's surface showed that EA plants were extensively colnized by Aspergillus fumigatus LH02 under high salanity. In phytohormonal anlysis, ABA contents in EA and NEA were almost similar. Howere, when plants were exposed th salt stress, ABA levels were found significantly low in EA compared to NEA plant. In isoflavone content analysis, aglycones, malonyl, acetyl and glucosides isoflavones (total 11 compounds) were analyzed for each treatment through extensive HPLC andalysis. The quantities of isoflavone were found higher in EA plant's leaves with and without salt stress compared to NEA plant leaves. In conclusion, such endophytic association can be beneficial to explore ways to improve crop production under stressful conditions.

We carried out the effect of Si levels (0.5, 1.0 and 2.0 mM) on ethylene and salicylic acid (SA) of hydroponically grown rice plants, after 6h, 12h and 24h of Si application. All samples were analyzed after applying wound stress for 30 minutes. In 6 h treatments, 0.5 and 1.0 mM of Si decreased ethylene production by 7% and 9.9% respectively, while elevated level of Si (2 mM) insignificantly affected ethylene production under same conditions. However 0.5 and 1 mM of Si enhanced endogenous SA contents by 2.6% and 17.3% respectively, while 2 mM of Si decreased SA contents by 3% as compared to control. Samples analyzed after 12h of 0.5, 1 mM and 2 mM Si application showed reduction of 11%, 4% and 1.7% respectively, while SA contents increased by 4% and 9.5% in 0.5 and 1 mM Si treatments. Samples analyzed after 24 h of Si treatment showed that 0.5 and 1.0 mM of Si inhibited ethylene production by 12.6% and 18.2% respectively, while 2 mM Si increased ethylene production by 11.9% as compared to control. It was observed that the SA content of rice was almost similar to control in 0.5 mM Si applied treatments, while 1 mM and 2 mM of Si increased SA contents by 6.5% and 6.9% as compared to control. It was concluded that Si alleviates the effect of wounding stress in rice by regulating ethylene and SA production.

Agricultural productivity is subjected to enormous environmental constraints, particularly to salinity and drought due to their higher magnitude of adverse impacts and worldwide distribution. Silicon (Si) was found to play a favorable role in salinity and drought stress alleviation of soybean cultivar Daewonkong. All growth attributes insignificantly improved with Si nutrition. The endogenous bioactive GA1 and GA4 content increased with the application of elevated Si level both under normal and stressful condition. JA contents sharply increased with NaCl and PEG application but decreses with Si added to salt and drought stress treatments. SA level increased with NaCl and PEG and was further enhanced with Si in the salt treated plants, but reduced with the combined application of Si and PEG. The endogenous bioactive GA1 and GA4, JA and ABA content of soybean leaves were analyzed through chromatograph/mass spectrometer (GC/MS) in selected ion monitoring (SIM) mode, while SA content was quantified with HPLC.

The adverse effects of salinity and drought on soybean cultivar Hwangkeumkong were also investigated. Endogenous bioactive gibberellins GA1 and GA4, jasmonic acid (JA), abscisic acid (ABA) and salicylic acid (SA) content and pertinent changes in response to basic and double NaCl (70 mM & 140 mM) and PEG (8% & 16%) were examined. We found that plant growth and yield components significantly reduced with the application of NaCl and PEG during pre-flowering and post-flowering growth periods. The endogenous bioactive GA1 and GA4content decreased under elevated salt and drought stress. However, an insignificant increase in GA4level was noted with 8% PEG, applied during post-flowering growth stage. JA levels significantly increased with NaCl and PEG applications, but declined with elevated PEG applied during post-flowering period. SA level drastically reduced with NaCl, while insignificantly reduced with PEG. Endogenous ABA contents of leaves increased with elevated NaCl and PEG application. The endogenous bioactive GA1 and GA4, JA and ABA content of soybean leaves were analyzed through chromatograph/ mass spectrometer (GC/MS) in selected ion monitoring (SIM) mode, while SAcontent was quantified with HPLC.