Determination of yield and quality characteristics of some cotton (Gossypium hirsutum L.) varieties in second crop conditions

This research was carried out to determine the yield and fiber quality characteristics of some cotton (Gossypium hirsutum L.) varieties under second crop conditions. The research was carried out in the experimental areas of GAP International Agricultural Research and Training Center Directorate (GAPUTAEM) in Diyarbakır province during the 2022 cotton growing season. In the study 9 cotton varieties, including 7 varieties (GW 2345, BA 1010, BA 440, Lima, Bomba, Optasia and Özbek 100) and 2 control varieties (STV 468 and DP 396), were used as material. In the study, significant statistical differences were obtained among the varieties in terms of seed cotton yield, fiber yield, plant height, boll weight, seed cotton boll weight, fiber fineness, fiber length, fiber elongation, short fiber ratio, fiber yellowness, fiber reflectance and spinning consistency index. Among the other characteristics examined, it was observed that the differences between the varieties were not significant in terms of the number of monopodial branches, number of sympodial branches, number of nodes of the first fruiting branches, number of bolls, 100 seed weight, ginning percentage, chlorophyll content, NDVI value, canopy temperature, fiber strength and fiber uniformity ratio. As a result of the study, it was determined that the seed cotton yield varied between 119,64 kg/da and 299,64 kg/da and the highest seed cotton yield was obtained from the GW 2345 cotton variety with 299,64 kg/da. Ozbek 100 and Bomba varieties followed the ranking. DP 396 and Lima varieties showed higher values in terms of plant height, and OZBEK 100 and DP 396 cotton varieties showed higher values than other varieties in terms of boll weight and seed cotton boll weight. No significant differences were found between the varieties in terms of the physiological parameters examined in the study. When fiber quality criteria are examined; it has been determined that the Lima variety has the finest fiber value and the highest brightness value, GW 2345 and Bomba varieties stand out in terms of fiber length and fiber elongation, GW 2345 variety stands out in terms of short fiber ratio and spinning consistency index, and Bomba variety stands out in terms of fiber yellowness value. In this research conducted under second crop conditions, the fact that GW 2345, OZBEK 100 and BOMBA cotton varieties came to the fore in terms of seed cotton yield, fiber yield and many fiber quality criteria shows that these varieties may be suitable for second crop cotton cultivation.