Pea aphids, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), from 4 geographically different localities were reared on a chemically defined diet. Other groups of aphids from the same 4 localities were reared on Vicia faba L. and on Pisum satvum L. All were maintained in the same controlled environment. Number of days to adult and survival rates were recorded for all aphids on all food sources. These trials were replicated 24 times. Aphid individuals from all 4 localities matured earliest and showed best survival rates on V. faba, indicating marked specificity for this food source. Randomly selected, newly molted 4th-stage nymphs of the F2 generation were wired according to the procedure described previously, starved for 1 hour, and then given access to a food source for 4 hours. Ingestion and salivation studies were replicated 10 times for individuals of each of the 4 populations on each of the rearing-recording combinations: (1) plant-to-diet, (2) plant-to-plant, (3) diet-to-diet, (4) diet-to-plant. Parameters studied were mean base time (no probing), mean salivation time, and mean ingestion time. Mean ingestion time data indicated that the aphids did not readily adapt to a new food source, regardless of whether it was plant-to-diet or diet-to-plant. They found the plant-to-diet change least acceptable, possibly because they were reluctant to probe the Parafilm® membrane. The fact that ingestion times for all 4 aphid types on each food source were similar suggests that diet composition rather than diet quantity may be the important variable in survival on a food source. Indications of an external physical stimulus to probing, possible correlation between ingestion time and survival rate, and biotypical differences in feeding behavior are discussed.
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D. L. McLean (1971) studied this question.