Dry weights were measured after drying the plants at 70°C for 72 h in oven. Total leaf area was measured with Laser Leaf Area meter (CI-203 model, CID Inc., USA). Portable photosynthesis measurement system (ADC BioScientific LCi Analyser Serial No. 31655, UK) was used to calculate the net photosynthetic rate (μmolm-2s-1), transpiration rate (mMm-2s-1) and stomatal conductance

(molm-2s-1) per unit leaf area of fully expanded leaves. For each measurement, readings were recorded in triplicates. For endogenous phytohormonal analysis of cucumber plants, the treated samples were immediately frozen in liquid nitrogen and kept until further use at -70°C. Samples were freezed dried in Virtis Freeze Dryer (Gardiner, NY, USA). Microscopic analysis Cucumber this website roots inoculated

with CSH-6H were sectioned and treated with sodium hypochlorite (2.5%) for 10 min for clarification. Experimental selleck kinase inhibitor conditions were kept aseptic during analysis. Inoculated roots were treated with 20% KOH for 24 h and rinsed with autoclaved see more DDW. The roots were then acidified with 10% HCl, stained overnight using 0.05% 0.1% acid fuchsin and 95% lactic acid. Finally, the roots were destained in 95% lactic acid for 24 h. The roots pieces were then subjected to light microscope (Stemi SV 11 Apo, Carl Zeiss). The root parts having active colonization were used for re-isolation of the inoculated CSH-6H with the method as described earlier. RWC, EL, proline, nitrogen assimilation, antioxidant and lipid peroxidation Relative

water content (RWC) and electrolytic leakage (EL) were measured following González and González-Vilar [27]. Free proline was estimated following Bates et al. [28]. Plant samples were oven-dried at 65°C and were ground to pass through 1-mm mesh sieves and analyzed for N using CNS analyzer (Carlo-Erba NA1500, why Carlo Erba Instruments, Milano, Italy). Antioxidant activity was measured on the basis of radical scavenging activity of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) as described Xie et al. [29]. The extent of lipid peroxidation was determined by the method of Ohkawa et al. [30]. The experiments were repeated three times. GAs extraction from fungal CF and cucumber plants To characterize GAs secreted in the pure fungal culture of bioactive endophyte, it was inoculated in Czapek broth (120 ml) for 7 days at 30°C (shaking incubator-120 rpm) as described previously [14, 24]. The culture and mycelium were separated by centrifugation (2500xg at 4°C for 15 min). The culture medium (CF; 50 ml) was used to extract and purify GAs as described by Hamayun et al. [22, 23]. Briefly, the pH of the CF was adjusted to 2.5 using 6 N HCl and was partitioned with ethyl acetate (EtOAc). Before partitioning, deuterated GAs internal standards (20 ng; [17, 17-2H2] GA1, GA3, GA4, GA8, GA12 and GA24) were added in the CF. Tritiated GAs i.e. [1, 2-3H2] GA9 and [1,2-3H2] GA20 were also added (obtained from Prof.