VARIABILITY IN POD FILLING CHARACTERISTICS OF PEAS (Pisum sativum L.) UNDER FIELD CONDITIONS

The average rates of pod dry weight increase, final pod weights and durations of pod growth were estimated for peas (Pisum sativum L.) growing in the field. The effects of plant genotype, field location and the time of season on these characters were studied in several populations of pea genotypes. Rate of pod filling and final pod weight were both affected by genotype, year and initiation time during the season. Effective duration of pod filling was not affected by any of these factors and final pod weight was always strongly related to the rate of filling. For 46 genotypes, the rate of pod filling ranged from 16 to 75 mg∙day−1 in a single location. Despite the large environmental and seasonal variation, the interactions with genotype were small and estimates of broad sense heritability were high. Across genotypes, rate of pod filling was correlated with weight per 100 seeds and final seed yields. The large changes in rate of pod filling during the season were similar in pattern in 2 yr. However, because...