REDISTRIBUTION OF STEM CARBOHYDRATE IN A DROUGHT RESISTANT AND SUSCEPTIBLE SHEATH CULTIVARS UNDER WATER-STRESS CONDITIONS

Two wheat cultivars viz. AZS-4, AZS-17 drought resistant and non-resis tant were grown in irrigated and non-irrigated conditions. The changes in stem water soluble carbohydrate (WSC) during post-jointing was stu died. Results for both cultivars were identical, anthesis and peak WSC concentrations were 5-6 days and physiological maturity 10-12 days ea rlier under non-irrigated than irrigated treatment. The concentration of WSC in stem continued to increase 5-10 days after anthesis and then declined till physiological maturity of grain. It is evident that ste m acts as a storage site for WSC from where it is remobilized in part to grain development. The pattern of storage and retranslocation was i dentical in both cultivars, however, in drought susceptible WSC were l ess on per plant basis.