Evaluation of irrigated cotton cultivars in South Africa

Cotton (Gossypium hirsutum) is a globally important fibre crop. The cottonseed has a high oil and protein content and is used for human and animal consumption. Innumerable commodities are made from cotton. Annual cultivar evaluations are essential to compare the yield and quality obtained in different production areas, to obtain experimental data to recommend the most suitable cultivar for a production area. The objective of this study was to evaluate the performance of different cotton cultivars under irrigation in South Africa. The cultivars planted from the 2003/2004 season up to the 2005/2006 season were NuOPAL, DeltaOPAL, DeltaOpal RR, LS9219 and SZ9314. The localities were Loskop (Mpumalanga Province), Makhathini (KwaZulu- Natal), Rustenburg (North-West Province), Vaalharts and Upington (Northern Cape) and Weipe (Limpopo Province). The Additive Main Effects and Multiplicative Interaction (AMMI) statistical model was used to describe the effect of cultivar x environment interaction on the yield of cotton planted under irrigated conditions. It is recommended that cotton producers should plant NuOPAL, since it was selected by the AMMI model as the best performer in respect of seed cotton yield and fibre yield (kg ha-1) in fifteen out of eighteen environments.