Quantitative variation in cold climate adapted white cabbage (Brassica oleracea L. var. capitata)

Abstract

The variation in growth period, mean head weight, and some form related characters was analysed in a cabbage breeding population. For all of the characters except growth period, the additive component of the variation was highly significant. Though not significant because of large interactions, the variation in growth period was due to additive as well as dominant gene actions. Dominance variance was of little importance for the other characters. A significant genotype by environment interaction was found for most of the characters observed. For growth period in particular, the implication is that it may be difficult to develop early, wide adapted varieties. Heritability estimates for half-sib selection varied from h2=0.70 for the head form to h2=0.38 for growth period. The heritability estimates for full-sib within half-sib selection were significantly lower. Estimated correlations between characters were considerably lower than those reported by others, ranging from -0.34 to 0.54. No reciprocal differences were observed.