Effect of Density on Reproduction and Survival of Pea Aphid on Cool Season Food Legumes

Abstract

The effect o f pea aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae) density per plant on reproduction and survival was studied on four cool season food-legumes, Faba bean, Field pea, Lentil and Grass pea in the greenhouse conditions. There was a
general trend o f decreasing survival with increasing aphid density though there was no significant difference in survival among four densities (2, 6, 10 and 14 nymphs/plant) on faba bean. While significantly (P < 0.05) higher survival was observed under the lower density (2/plant) on lentil. Progeny production declined with increasing aphid density per plant on the four crops. The highest mean progeny production (37.3 offspring/female) was observed at the lowest aphid density o f 2/plant, among all the plant species tested. The number o f nymphs produced per aphid was significantly lower on faba bean compared to the other host plants regardless of density, indicating that faba bean is less suitable for the pea aphid survival and reproduction.