Location and crop-year effects on sugarcane genotype performance for the coastal short cycle breeding programmes in South Africa

Abstract

Genotypes are tested in several environments to evaluate the influence of genotype × environment interactions prior to their release as cultivars. The objective of this study was to determine location and crop-year effects and their implications on coastal short cycle sugarcane breeding programmes. Data for yield, quality and stalk traits were collected from five trial series each planted to two and three sites at Gingindlovu and Empangeni, respectively. Trials were harvested in the plant, first and second ratoon crops. Genotype effects were highly significant (p < 0.0001) for all traits, indicating differences in genetic values among genotypes within and across populations. Genotype × location was non-significant (p > 0.05), indicating that genotype trait value rankings were similar at both locations. Genotype × crop-year was significant (p < 0.05) for tons cane per hectare, tons sugar per hectare, estimable recoverable crystal, brix% cane and pol% cane, indicating that genotype values for these traits fluctuated differently across ratoons. Genotype × location × crop-year was non-significant (p > 0.05) for all traits. Crop-year effects had a greater influence on genotype performance than location effects. Therefore testing genotypes across more ratoons would be more important than across locations.

Keywords:

• genotype × crop-year
• genotype × location
• quality
• stalk traits
• sugarcane
• yield