Drought Effects on Green Pea Texture and Related Physical-Chemical Properties at Comparable Maturity

Abstract

Yield and seed texture were studied in green peas (Pisum sativum L.) subjected to drought stress during flowering and pod filling. Field experiments were conducted with two cultivars on a sandy loam soil and drought conditions were obtained using movable rain shelters. The plants were harvested at three to five stages of maturity determined by tenderometer values and the concentration of alcohol-insoluble solids (AIS). Measured variables were related to the concentration of AIS in order to eliminate the influence of maturity when comparing between stress and nonstress conditions. Drought stress during flowering or pod filling reduced yield, but did not affect the size distribution consistently. To lessen the differences caused by variation in size distribution, all quality measurements were carried out on peas graded to 8.75 to 10.2 mm. Drought stress increased the concentration of sucrose at an AIS concentration of 140 g·kg-1. Besides the concentration of dry matter and starch the mean pea weight and testa weight did not reflect any consistency in relation to drought-stress conditions. The sensory scores for pea mealiness was not significantly increased in drought stress, and other sensory quality attributes were unaffected. In this study, the effect of drought stress on pea texture quality is weak and inconsistent when comparisons are made at the same stage of maturity. As texture quality is highly correlated to stage of maturity, the tenderometer value or AIS concentration is reliable when determining time of harvest for the production of high quality peas irrespective of drought-stress conditions during maturation.