The experiment was conducted at the research field of Agronomy Division BARI, Joydebpur, Gazipur during the rabi season of 2013-14. The soil of the research area belongs to the Chhihata series under AEZ-28. The soil was clay loam with pH 6.1. The monthly mean maximum air temperature of 34.330C and minimum 8.340C were recorded. Moreover, 0.3 mm, 3.8 mm, 0.40 mm and 4.5 mm rainfall that occurred 22, 81,112 and 115 days after seed sowing. Thirty three (33) grass pea genotypes namely BD 5253, BD 5260, BD 5261, BD 5262, BD 5263, BD 5264, BD 5265, BD 5267, BD 5268, BD 5269, BD 5270, BD 5271, BD 5272, BD 5273, BD 5274, BD 5275, BD 5276, BD 5278, BD 5279, BD 5280, BD 5281, BD 5282, BD 5284, BD 5285, BD 5286, BD 5288, BD 5291, BD 5313, BD 5317, BD 5316, BARI Kheshari-1, BARI Kheshari-2 and BARI Kheshari-3 were evaluated under drought and control condition (No drought). The experiments were laid out in factorial randomized complete block design with three replications. The seeds were sown on 30 November, 2013 maintaining row to row distance at 30 cm with continuous sowing. Fertilizers @ 23-18-20 kg ha-1 NPK were applied in the form of Urea, Triple super phosphate (TSP) and Muriate of potash (MoP) respectively. All fertilizers were applied at the time of final land preparation. A light irrigation was given after sowing of seeds for uniform germination both for control and drought condition. The control plots were irrigated three times at 25, 45 and 65 days after sowing (DAS). Other intercultural operations like-thinning, weeding, and pesticide application were done as and when required. For dry matter estimation, 5 plants were sampled at 5 days interval up to maturity. The collected samples were dried component-wise in an oven at 70oC for 72 hours. Moisture content of soil was measured by gravimetric method. The yield component data was taken from 10 randomly selected plants prior to harvest from each plot. At harvest, the yield data was recorded line wise. The collected data were analyzed statistically and the means were adjusted following LSD test. Four selection indices viz. Yield Stability Index/ Relative Yield and Stress Tolerance Index (Sharma et al, 2009) were calculated by using the following formula:
1) Relative yield/ Yield
Stability Index (YSI) =
2) Stress Tolerance Index (STI) = (Yp/Ys)/YP2
3) Stress intensity (SI %) = 1- (Ys/Yp) x 100
Here Yp = Yield of cultivar in normal condition, Ys = Yield of cultivar in stress condition, YP = Total yield mean in normal condition and YS = Total yield mean in stress condition.