SCREENING OF SALT TOLERANT GENOTYPES OF SOYBEAN

Abstract

An experiment was carried out in the central laboratory of Sher-e-Bangla Agricultural University, Dhaka during January to March 2017 for screening salt tolerant genotypes of soybean. The experiment consisted of 15 soybean genotypes viz, V 1 (Shohagh), V (BD-2326), V 6 2 (BARI soybean 5), V (BD-2337), V 7 (BD-2346), V ii

3 (BARI soybean 6), V 8 (BD-2349), V 9 4 (BD-2324), V (BD-2351), V (BD2352),

V 11 (BD-2353), V 12 (BD-9402), V 13 (BD-9418), V 14 10 (BD-9420) and V (BD-9426). Seeds of 15 genotypes were collected from Bangladesh Agricultural Research Institute (BARI). The performance of the genotypes was tested under 5 levels of salinity viz. Control (No salt), 5, 10, 15 and 20 dSm -1 . The experiment was laid out in Completely Randomized Design (CRD) with five replications. There are significant differences observed among the different levels of salinity in case of almost all the parameters. For all the soybean genotypes used in the study, the highest seedling emergence rate was observed under control condition where no salinity stress was imposed. Salinity stress both at 15 dSm -1 and 20 dSm NaCl significantly reduced the seedling emergence rate for all soybean genotypes. The highest germination rate (85.88%) was found from V (BARI soybean 6) followed by V 2 (BARI soybean 5) and V 9 3 (BD-2351) which were 83.64 and 69.98% respectively at control and the lowest germination rate was found from V (BD2326)

(18.97%) followed by V 11 (BD-2353) (24.09%), V (BD-2352) (30.10%) and V 14 (BD-9420) (29.65%) at 20 dSm -1 10 . Accordingly, more or less similar trend was found on shoot length, root length, fresh weight plant -1 -1 5 , dry weight plant , relative water content, turgid weight, water retention capacity, water saturation deficit and vigour index. Among 15 soybean genotypes V (BARI soybean 5) and V 9 3 (BARI soybean 6), V (BD-2351) are salt tolerant which are attributed to higher germination rate, shoot length, root length, dry weight, relative water content, water retention capacity and vigour index and rest of the soybean genotypes were found to be sensitive to salt stress.