Evaluation of Drought Stress Tolerance Efficiency of Wheat (Triticum aestivum L.) Genotypes at Germination and Seedling Stages

Abstract

Wheat (Triticum aestivum L.) is world-wide used as a staple food crop that significantly affected by abiotic stresses such as high-low temperatures and drought. Tolerance to water stress is a complicated parameter in which wheat performance influences by a number of characteristics. In the present investigation, a feasible unconventional strategy has been applied by employing PEG-6000 in order to in vitro screening of ten bread wheat cultivars for drought tolerance at germination and seedling stages during the year 2014-15. Water stress condition was induced by 15%, 20% and 25% of PEG-6000 containing nutrient solutions and maintained in a hydroponics culture treatment with three replications applying completely randomized design (CRD). After 10 days, seven stress-associated indices, PI, GSI, PHSI, RLSI, SLSI, DMSI and RWCSI from drought-stressed and non-stress wheat seedlings were estimated and demonstrated that all the indices efficiently illustrate highly drought tolerant and susceptible wheat genotypes. Statistical analysis including ANOVA, mean rank, standard deviation of ranks and rank sum (RS) revealed that germination percentage, shoot length and root length significantly declined due to water deficit and distinguished genotypes, SUJATA, MP1500 and HI1077 as highly drought tolerant genotypes and significantly superior in seedling growth tolerance under increased levels of water stress whereas, GW322, MP1531 and GW273 was found susceptible to drought stress. It was concluded that measuring stress by elicited indices varies with the stress severity and provides an effectual platform for rapid screening of tolerant genotypes against potent drought stress at seedling stage.