Evaluation of cauliflower genebank accessions under organic and conventional cultivation in Southern Germany

Abstract

In recent years, public attention increased towards products from organic farming due to their presumed higher quality and health benefits. Frequently, organic farming is characterized by lower yields than conventional farming. One reason may be the use of varieties that were bred for conventional cultivation and are not adapted to organic farming. This raises the question if high yielding varieties differ in their performance under different cultivation methods allowing the selection of varieties with superior performance in organic cultivation. To answer this question and to identify suitable genotypes we evaluated a collection of 178 cauliflower genebank accessions under organic and conventional farming conditions. Two traits (curd width and time to budding) were evaluated for mean and stability. We observed a significant genotype × cultivation method interaction because genotypes differed in their performance between cultivation methods. Of the two traits investigated, curd width showed a lower heritability (Formula presented.) = 0.37) and low genotypic correlation between organic and conventional systems, compared to days to budding that show high heritability (Formula presented.) = 0.87) and a high correlation between the two farming systems. Our results demonstrate that the selection for curd width should be preferably conducted under organic conditions, whereas selection for number of days can be carried out under organic or conventional conditions. The evaluation of genotypes at both environments identified genotypes that may be used as parental lines for breeding under organic conditions.