Growth, development and survival of Acyrthosiphon-kondoi (Homoptera, Aphididae) on five cultivars of Lucerne
The performance of Acyrthosiphon kondoi Shinji on winter cuttings of 3 American cultivars of lucerne (cv CUF-101, cv De Kalb 185 and cv Matador) and 2 Australian cultivars (cv Hunter River and cv Trifecta) was monitored in a laboratory study at 20°C. Growth rates, development times, survival rates, embryo numbers and embryo size were recorded on each variety. Aphids reared on cv Trifecta (a tolerant cultivar) performed significantly better than aphids on other cultivars. No significant differences in performance were noted between aphids reared on cv CUF-101 and 3 susceptible varieties. High levels of variation in performance statistics were observed within treatments. The problem of discriminating between host-plant resistance to the aphid and the effect of plant growth activity on the aphid are discussed.