Fertilization Effects of Phosphorus and Sulfur on Chemical Composition of Seeds of <i>Pisum sativum</i> L. and Relative Infestation by <i>Bruchus pisorum</i> L.

Abstract

The effect of different rates of phosphorus (P) and sulfur (S) application to soil on chemical composition and level of seed infestation by Bruchus pisorum was studied under field conditions using three pea (Pisum sativum L.) varieties. The cultivar Ballet (BA) had greater concentration of total phenols, phytic acid, and protein (P < 0.05) than cultivars Renata (RE) and Solara (SO). Tannin content in RE was less than that in SO and BA (P < 0.05). A close correlation (r2 = 0.928, 0.987, 0.984) was observed between different P application rates and phytic acid levels in RE, SO, and BA, respectively. Otherwise, only SO showed a linear correlation between S fertilization and total protein content (r2 = 0.867). Sulfur application rate was correlated with albumin fraction (r2 = 0.987, 0.979, 0.750), Cys (r2 = 0.951, 0.884, 0.764), and Met (r2 = 0.995, 0.893, 0.964) contents of RE, SO, and BA cultivars, respectively. The proportion of grains infested by B. pisorum was greater in BA than in SO and RE (P < 0.05). Infestation levels in all cultivars were unaffected by fertilization rates (P > 0.05). However, a linear correlation between both protein and phytic acid content and B. pisorum infestation was observed (r2 = 0.735 and 0.732, respectively). The results suggest that greater phytate and protein contents reduce the risk of Bruchus infestation in pea seeds. Keywords: Tannins; phytates; nutritional quality; Pisum sativum; insect infestation; Bruchus pisorum; fertilization