The vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), is a major pest of vineyards. Here, we tested the efficacy of the mating disruption method against the pest when applied during one or two successive years in high and low infestation levels. Following 1 year of treatment, at low initial infestation levels a shutdown of pheromone traps was observed, along with a significant reduction in infested vines. With initially high infestation levels, a gradual reduction in infested vines was observed, with a trap shutdown seen only after the second year of pheromone application. We discuss the implications of the male mating disruption method for this pest in which the wingless females are aggregated with limited movement among vines, offering multiple mating opportunities for the flying male.

The resistance mechanism in both accessions appears to be antibiosis affecting nymph survival. These resistant accessions may be used as rootstock or as a source of resistant genes in breeding programmes.

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The pear psylla, Cacopsylla bidens (Sulc), is one of the most damaging pests of commercial pear orchards in Israel. However, growers today have only two pesticides left to control the pear psylla, therefore alternative control methods are needed. Our goal was to find ways to control the psylla population through rational use of cultural control methods: manipulating the levels of nitrogen fertilization, and using growth regulators. Our objectives were to determine the impact of nitrogen fertilization level on pear psylla populations, the impact of application of plant growth regulators (clormequat chloride and prohexadion-calcium) on psylla populations, and whether there is an interaction between the two factors in a semi-field-scale and in field-scale experiments. Higher oviposition and nymph development rates were found in trees that had higher leaf-nitrogen contents. Lower oviposition, nymph survival, and nymph development rates were found in trees that were treated with growth regulators. The suppressive impact of growth regulators was expressed even in trees with high nitrogen levels. We concluded that psylla population levels in pear trees can be reduced by using lower levels of nitrogen fertilization and that growth regulators impair psylla growth and development, and may possibly be used to reduce psylla populations.