EFFECT OF SALINITY ON GROWTH AND YIELD OF COTTON

This experiment was conducted at Professor Purnendu Gain Field Laboratory, Khulna University, Khulna, Bangladesh from September 17, 2019 to March 28, 2020 to determine the effect of salinity on growth and yield of cotton. The experiment was set up in the form of a Completely Randomized Design (CRD) which include two factors, genotypes (CB-9 and CB-15) and salinity treatments (0 dS m-1, 4 dS m-1, 8 dS m-1 and 16 dS m-1). At 45 DAS, maximum Shoot Fresh Weight, Shoot Dry Weight, Shoot Length was recorded (10.20 g, 3.33 g and 32.33 cm, respectively) in CB-9 and minimum (6.58 g, 1.77 g and 25.83 cm, respectively) in CB-15 at 16 dS m-1. On the other hand, at 90 DAS, Shoot Fresh Weight, Shoot Dry Weight, Shoot Length was recorded maximum (37.27 g, 9.42 g and 63.33 cm, respectively) in CB-9 and minimum (31.64 g, 5.68 g and 53.83 cm, respectively) in CB-15 at 16 dS m-1. Like shoot parameters, other morphological parameters such as Root Fresh Weight, Root Dry Weight, Root Length, and Leaf Area also showed more decreasing tendency (3.22 g, 1.06 g, 11.33 cm and 36.35 cm2) in CB-15 compared to CB 9 (4.11 g, 1.85 g, 16.17 cm and 36.35 cm2) at 16 dS m-1. In case of physiological parameters, CB-9 also performs better than CB-15. At 45 DAS, Leaf Relative Water Content, Chlorophyll ‘a’ and ‘b’ Content was recorded maximum (76.41 %, 2.10 mg/g and 0.91 mg/g, respectively) in CB-9 and minimum (67.15 %, 1.43 mg/g and 0.42 mg/g, respectively) in CB-15 at 16 dS m-1. On the other hand, at 90 DAS, Leaf Relative Water Content, Chlorophyll ‘a’ and ‘b’ Content was recorded maximum (59.04 %, 1.70 mg/g and 0.72 mg/g, respectively) in CB-9 and minimum (56.41 %, 1.03 mg/g and 0.47 mg/g, respectively) in CB-15 at 16 dS m-1 .Out of the two genotypes tested, CB-9 showed a better overall performance because Number of bolls, Single boll weight, yield, and Ginning Out Turn was recorded maximum (11.00, 3.47 g, 968.6 kg/ha and 28.52 %, respectively) in CB-9 and minimum (4.67, 2.65 g, 322.3 kg/ha and 21.06 %, respectively) in CB-15 at 16 dS m-1. So, there was a greater reduction of values of all the parameters in case of CB-15 compared to CB-9 with increased salinity. Considering all the growth, yield and yield contributing parameters, CB-9 was supposed to be superior genotype as it showed more resistance to the salts in compared to CB-15.

• Supervision