Emergence of Alfalfa Seed Chalcid, Bruchophagus roddi (Hymenoptera: Eurytomidae), from Overwintered Seeds in Oklahoma

Abstract

In 1983, alfalfa seed chalcids (ASC), Bruchophagus roddi (Gussakovsky), emerged from overwintered alfalfa, Medicago sativa L., seeds between 2 May and 5 August. In 1984, this emergence occurred between 15 April and 3 August. Seeds were sorted from screenings that had been collected in the fall in 1982 and 1983 from four locations in Oklahoma. Peak emergence of ASC was in mid-June, with significantly higher emergence occurring during the entire month of June. ASC emerged earlier at lower elevations and at more southern locations than at higher elevations or at the most northern location. Male ASC emerged earlier and in greater numbers than females until early June. Thereafter, more females emerged. Overall, 60% of emerging ASC were female. A small number of ASC (39) emerged the second year (1984) from seeds collected in the fall of 1982.