Crude Protein and Proline in Dry Bean Seed Respond to Weeding and Soil Fertility Regimes

Abstract

The objective of this study was to investigate the effect of weeds and fertilizer application on dry bean seed quality. Four dry bean (Phaseolus vulgaris L.) cultivars, Caledon (C), Ukulinga (U), Gadra (G) and uMtata (M) were planted for seed production using a field experiment designed as a split, replicated three times. There were three levels of weeding W0 (no weeding), W1 (weeding until 50% flowering) and W2 (weeding all the time until harvest). The weeding treatments were split into no fertilizer application (F0) and optimum fertilizer application (F1) according to soil fertility analysis. At harvest maturity, seeds were compared for quality with respect to size, germination and total protein content. Proline content was determined as a measure of crop response to the weed and fertilizer stresses during crop production. Although seed size was affected by management stress, seed germination was not significantly affected by weeding and fertilizer even when it was explored in terms of seed vigor by determining rate of germination and seedling size. However, weed management and fertilizer application significantly affected proline and total crude protein contents in seeds (P < 0.05). The findings of this study show that the biotic stress of weeds and abiotic stress of soil fertility can be used to determine seed physiological quality of dry bean seeds.