Morphological influences on the seed yield of field peas

Abstract

In a preliminary trial at Perth with spaced plants which were supported to prevent lodging and allow for irrigation, the seed weight on plants was correlated with the ability of pea plants to produce reproductive nodes on the main stem and branches. Tall cultivars such as Dundale, Dun and Wirrega produced more aerial branches than dwarf cultivars like Huka which gave more basal branches. By contrast, in the dry, short-season Mediterranean climate of the Western Australian wheatbelt at Merredin, the seed yield of peas was derived principally from yield components on the main stem. The plant characters; the number of reproductive nodes, plant height and seed number per pod, had a significant (P< 0.01) and positive correlation with seed yield. The early- and mid-flowering cultivars, Collegian and Dundale (67 and 72 days to flower respectively), had more reproductive nodes on the main stem, with more seeds produced on the first six reproductive nodes than later flowering (88-96 days) cultivars such as Dun and Wirrega. At Merredin, basal branch number was negatively correlated with seed yield and tall cultivars like Collegian, Dundale and Dun had significantly (P< 0.05) less basal branches. Plant breeders should select for increased seed number per pod in early flowering, medium to tall pea plants, to improve the total seed weight from the first three reproductive nodes produced on the main stem.