Development of visual tools for selecting qualitative corm characteristics of taro (Colocasia esculenta (L.) Schott)

Abstract

Taro (Colocasia esculenta (L.) Schott) is an allogamous and polymorphic species with thousands of cultivars. Tremendous morphological variation can be created by artificial genetic recombination. The breeding of taro is expensive, especially when the breeders have to deal with large populations of 10 000 or more individuals. One of the most efficient ways to improve the breeding efficiency is to start selection in an early stage of development, without uprooting the plants, which usually takes 15 months after the germination of seeds. Such an approach has been considered for determining taro corm flesh and corm fibre colours, as these traits are very important for marketing. In the present study, the phenotypic correlation analysis shows that most of the colours of the corm flesh and corm fibres can be determined by scoring the colour of the petiole base and the colour of the lower part of the petiole (2–3 mm above the base). This can be done in an early stage of development and speeds up the recurrent selection process.