POD AND SEED GROWTH OF BEAN-PLANTS

Four varieties of bean (Phaseolus vulgaris) were sown in the greenhouse and in the field to study pod and seed growth and quantify yield. One variety, 'Cacahuete 72', has determinate growth (Type I)' the other three, 'Zacatecas 21-1-2', 'Michoacan 12A-3', and 'Chapingo 72', have indeterminate growth (Type II). In the greenhouse, after anthesis (defined as day 0 in pod and seed growth), pod length (cm) and seed length (mm) and fresh and dry weight of pods and of seeds in each pod (mg) were measured in ten pods per variety every three days. In the field, at the time of physiological pod maturity, dry weight of seeds per pod and per plant, number of seeds per pod and per plant, size of seeds (dry weight of 100 seeds), and number of pods per plant were noted for 40 plants per variety. It was found that pods and seeds grow very rapidly in the few days, and that increase of fresh and dry seed weight occurs in the three phases. No relationship was found between rate of pod and seed growth and yield per plant (dry seed weight). Number of seeds per plant appears to be the variable that shows greatest correlation with yield.