Impact of foliar applied glycine betaine on growth and physiology of wheat (Triticum aestivum L.) under drought conditions.

Drought is the major abiotic limiting factor for healthy crop growth. Glycinebetaine applied under drought mitigates the adverse effect of drought and improved the plant’s tolerance. The present investigation was conducted to find out the response of wheat ( Triticum aestivum L.) cultivars (Lasani-2008, Auqab-2000) under water deficit conditions to exogenous application of 100 mM glycinebetaine at different growth stages, Zadoks GS 22, GS 60 and GS 73, representing tillering, flower initiation and grain filling stages, respectively. The objective was to find out the best glycinebetaine (GB) application stage for mitigating the negative effect of drought stress on wheat plants. During investigation various growth traits (plant height, spike length, number of spikelets per spike, number of grains per spike, 1000-grain weight and grain yield per plant) and physiological parameters (water potential, osmotic potential and turgor potential) of crop were recorded using standard procedures. Drought stress at all three critical growth stages adversely affected (P<0.05) all the growth, yield and physiological components of wheat plant. The exogenous application of GB at all three critical growth stages improved the drought tolerance of plants and improved the growth, yield and physiological performance of wheat, however, grain filling stage was found more responsive.