ABSTRACT

Plant growth regulators (PGRs) are used in cotton production to optimize yield and quality and even suppressing excess growth whenever necessary. Experiments were conducted PGRs are used in cotton production to optimize yield and quality and even suppressing excess growth whenever necessary. Experiments were conducted in 2017 at Cotton Seed Multiplication, Training and Research Farm, Sreepur, Bangladesh to study the response of cotton yield and quality to different plant spacings, concentration and time of application of mepiquat chloride (MC) growth regulator. The maximum seeds boll-1 (119.61) was recorded at spacing 75 cm × 30 cm and lowest seeds boll-1 (116.92) was marked from spacing 45 × 30 cm. in respect of MC, the highest seeds boll-1 (122) was obtained from foliar sprayed at 3.0 ml L-1 water at 75 DAE and the lowest (109.33) was observed in 1.0 ml MC L-1 water at 25 DAE. Considering combined action, seeds boll-1 was marked highest (122.67) from 3 ml MC L-1 water at 75 DAE with 60 cm × 30 cm spacing and became lowest (106.42) at 1 ml MC L-1 water sprayed at 50 DAE with 45 cm × 30 cm spacing.  So, plant spacing of 60 cm x 30 cm can be practiced for profitable cotton production in Sreepur areas of Bangladesh.

Key words: Plant spacing, growth regulator, time of foliar, seed boll, cotton.