Yield and some agronomic parameters of upland cotton as affected by planting dates

Abstract

A field experiment was conducted at ICI Research Farm, Multan to evaluate the effect of different sowing dates on plant height, number of monopodia, number of sympodia, number of bolls per plant, boll weight, seed cotton yield kg/ha of two upland cotton varieties (ICI-2121 and ICI-2424) developed by ICI Pakistan Limited, Multan against a standard check variety IUB-2013 during 2019, and 2020 years.  These varieties were planted on 1^st April, 15^th April, 1^st May, 15^th May, 1^st June, and 15^th June, at ICI Cotton Research Station, 19-Kasi Vehari Road, Multan.  Results revealed that statistically highly significant differences in planting dates were observed for all the parameters studied except number of monopodial branches and boll weight which depicted non-significant differences. Regarding varieties and interaction between varieties and planting times, similar trend of statistical differences was observed. As regards to planting dates, generally, all the parameters under study showed their maximum performance when crop was planted on 1^st May followed by 1^st April planting date, whereas, minimum performance of the parameters was recorded when the crop was planted on 15^th June followed by 1^st June. Regarding varietal performance, on an average, maximum plant height (146cm) was observed in ICI-2121 followed by IUB-2013. Same trend of performance of varieties regarding number of monopodia and sympodia per plant was observed.  Regarding average number of bolls per plant in different varieties, it was observed that ICI-2121 produced maximum (32 bolls) followed by ICI-2424 (31 bolls) and IUB-2013 (28 bolls) irrespective of planting dates. The same trend of varietal performance regarding boll weight was recorded. When seed cotton yield (kg/ha) was evaluated, on an average of varieties, ICI-2121 produced maximum seed cotton yield (1228 kg/ha) followed by ICI-2424 and IUB-2013 which produced 1147 and 1046 kg/ha seed cotton yield respectively irrespective of planting dates. It was concluded that under agro-climatic conditions of Multan, 1^st May planting date was evaluated as optimum cotton sowing time. Before or after 1^st May, this study does not recommend growing cotton in this particular zone.  Among cotton varieties, ICI-2121 is recommended for sowing under this planting time being producing higher yields.