Feeding injury, oviposition, and nymphal survivorship of the potato leafhopper on red maple and Freeman maple clones

Feeding injury, oviposition, and nymphal survivorship of the potato leafhopper, Emponsca fabae (Harris), were measured among 5 red maple, Acer rubrum L., clones and 2 Freeman maple, A. X freemanii E. Murray, cultivars. Symptoms of feeding injury among the 5 red maple clones varied in severity among trees in the field. Red maple clone 56026 was the most susceptible, and red maple clones 57775 and 55410 were the most tolerant. The Freeman cultivars were most tolerant to feeding, with 'Jeffersred' showing no sign of insect injury. Oviposition was significantly higher on the susceptible clone 56026, but significantly lower on Jeffersred than on the other clones. Fewer nymphs became adults when reared on 'Indian Summer' than when reared on the other clones. Although the data showed that red maple is more susceptible to feeding injury by the potato leafhopper than Freeman maple, no clear-cut relationship exists between susceptibility to feeding injury and host acceptability for oviposition or host suitability for nymphal development. The differences among the maple clones tested in this study suggest that red maple and Freeman maple may have different mechanisms of resistance against the potato leafhopper.