Impact of Earliness, Flowering Time and Plant Design on Late Sown Cotton Production

Abstract Extremely diversified cropping environments prevails in most of the cotton growing areas of the country due to the prevailing rainfed conditions and thus cotton is cultivated over a prolonged period. This study examined the production and growth pattern of 8 cotton genotypes to find out the most effective strategies that could be transformed into breeding traits. Four experiments were conducted in 2018 and 2019 at two locations in Dera Ismail Khan to associate the 8 genotypes at 3 planting densities and two sowing dates. Various attributes like days to 1st flower opening, affective time of flowering, monopodial branches per plant, height of plant at the time of harvesting, ratio of height to node length of fruiting branch and average number of bolls retained at the 1st site of fruiting branch were investigated. Results revealed two ideotypes which performed better than the others. Genotype CIM-632 yielded better in late sowing-high plant density and regarded as by less growth of vegetative branches and early start of flowering, short flowering duration and less bolls retained at the 1st position of sympodia. Genotype CIM-663 and CIM-343 performed outstandingly in early sowing-low plant density and regarded by more growth of vegetative branches, delayed flowering, lengthy flowering duration and more bolls retained at 1st position. Based on these attributes, a breeding scheme for these ideotypes is proposed with high heritability for flower opening, height of plant at the time of harvesting, ratio of height to node and fruiting branch length and medium heritability for monopodial branches, effective flowering time and bolls retained at 1st position of sympodia (fruit branch).