Effect of drought stress on chlorophyll content, protein and total free amino acid in [Cajanuscajan(L.)Millspaugh]

Physiological and biochemical analysis responses of 6-day-old seedlings of two pigeon pea (Cajanuscajan(L.) millspaugh) cultivars namely ICPL-85063 (short duration, lakshmi) and ICPL -87119 (medium duration, Asha) were studied. Stress was applied with polyethylene glycol (PEG-6000) and water potentials were: zero (control), -0.3Mpa (50mM),-1.1Mpa (100mM) and -2.3Mpa (150mM). In this study, the water stress effects on different parameters like chlorophyll content, protein and total amino acid content was measured following the standard methods. Total free amino acid content registered higher values in ICPL-85063. The protein and total chlorophyll content was observed as lower values when compared to their controls in lakshmi cultivar. It was observed that amino acid content was highest in stress level was -2.3Mpa and the least exist in blank. The results of chlorophyll content demonstrate a concentration dependant decline with increasing concentration of polyethylene glycol (PEG-6000). ICPL-85063 cultivar showed better performance in total amino acid content than Asha cultivar. It was established that the applied doses of PEG-6000 caused stress on young pigeon pea plants, which found suppression of photosynthesis.