Integrated effect of planting dates and irrigation regimes on morpho-physiological response, forage yield and quality, and water use efficiency of clitoria (Clitoria ternatea L.) in arid region

A 2-year field experiment (2015/2016) was conducted on clitoria planted on May 20 as early (P-E) and June 20 as late (P-L) under 100% = I-100%, 80% = I-80% and 60% = I-60% of allowable soil moisture depletion (ASMD). The objective was to investigate the complementary effect of planting date and deficit irrigation on morpho-physiological responses, forage quantity and quality, and water use efficiency (WUE) of clitoria. Early planting date (P-E) significantly improved almost all attributes. Clitoria plants exposed to (I-100% or 80%) had higher almost parameters except for leaf/stem ratio (LSR), protein, and WUE in both seasons. Higher cumulative dry forage yield CDFY (6.5 and 6.4 t ha(-1)) and cumulative protein yield CPY (1.4 and 1.2 t ha(-1)) resulted from I-80% and I-100% whereas, highest WUE (1.8 and 1.6 kg m(-3)) from I-60% in both the seasons, respectively. Clitoria planted early and irrigated with I-100% or 80% had higher morpho-physiological responses and yields in both cuts of both seasons. Therefore, the adverse effects of drought can be diminished by planting early (P-E) and watering with (I-100% or 80%), particularly under limited water and could be suggested as a non-monetary practice for upgrade the drought tolerance in clitoria and maximizing yield and quality in arid environments.