Genetic Diversity and Agricultural Potential in Phaseolus vulgaris L

Summary

To assess the potentialities of Ph. vulgaris for haricot type bean production in Britain, a large collection of types was surveyed. One hundred varieties, mostly but not exclusively bush types, were grown both in the greenhouse and in the field. Characters of agronomic importance were evaluated. The morphological basis of the difference between the climbing and the bush habit was shown to be the interaction between two character contrasts, indeterminate versus determinate vegetative growth, and long versus short internodes. The four classes resulting from this interaction were identified and are described. Flowering habit, pod type and seed size were surveyed. Among the bush beans, wide variation in day length sensitivity in flowering was shown, and it is clear that day length neutral types can easily be selected. Among the determinate dwarfs, pods are either leathery or fleshy. Leathery types dry out readily, and do not dehisce freely in the field, and are therefore agronomically desirable in dry bean production. Fleshy pods are used for culinary purposes. The indeterminate bush types included in this survey have parchmented pods, which tend to dehisce when dry, and hence are subject to crop loss in the field. A wide range of seed size and seed colour is available for selection according to requirement. Two small variety trials yielded evidence that Colombian determinate bush types grow and crop satisfactorily within the limits of the growing season in eastern England. From two spacing trials, optimum within-row spacing was deduced.