SCREENING OF BLACKGRAM VARIETIES FOR TOLERANCE TO SALINE IRRIGATION WATER

The effect of salinity in irrigation water on germination, crop stand at different stages and yield of nineteen released and pre-release varieties of blackgram was studied. Saline water with different electrical conductivities (dSm-1) viz., control (best available water-BAW), 2 E.C., 4 E.C. and 6 E.C. was used as irrigation water for rabi blackgram crop in a non-saline sandy loam soil of Bapatla, Andhra Pradesh. It was important to observe that the different salinity levels did not affect the germination percentage of varieties tested during the two years of study. The results indicated that at 2.0 EC level, variety LBG-623 recorded highest mortality rate followed by LBG-727, 17, 22 and LBG-733. Lowest mortality levels of below 10% were recorded in LBG-20, 402, 611, 648, 685, 726, 730, 733, 738 and T-9. At 4.0 EC most of the varieties registered mortality rate between 20 and 50 percent, while at this E.C. varieties LBG-22, LBG-402 and LBG-738 recorded low mortality rates. At 6.0 E.C. (dSm-1) LBG-402 and LBG-738 maintained lower mortality values during both the years of study, while in other varieties the mortality rate was still higher. This indicated that in other varieties, considerable damage has been done at 4.0 EC level itself. During two years of study, there was significant variation in grain yields between all four treatments. The highest yields of seed were recorded in varieties LBG-733, 726, 738, 723 and 727 under BAW. In other salinity levels (2.0, 4.0 and 6.0 EC levels), LBG-738 performed better than all other varieties recording 9.89 q ha –1, 6.54 q ha –1 and 5.2 q ha –1, respectively. Varieties LBG-648, LBG-708, LBG-723 and LBG-726 also performed commendably as compared to other varieties.