A study on the incidence of woolly poplar aphid, Phloemyzus passerinii (Hom.: Aphididae) on poplar species and clones in Hamedan province, Iran

Woolly poplar aphid, Phloeomyzus passerinii (Signoret), is considered as an important and serious pest of poplar in Iran and many countries. During 2002-2003, resistance and susceptibility of 12 poplar clones to P. passerinii were evaluated in Hamedan province of Iran. Number of formed aphid colonies found in a surface unit was counted three times during a growing season. The clones Populus alba 58/57, P. deltoides 72/51, P. deltoides missoriensis, P. x. euramericana 214, P. nigra 62/72, P. nigra 62/140 and P. nigra 62/149 were immune to the insect pest, but the remaining of P. nigra clones were infested variously. Analysis of variance conducted on obtained data, revealed a significant difference (α = 1%) between the clones. Mean infestation of P. nigra 56/72 was significantly higher than other studied clones in all sampling dates. Mean infestation of branches (at four main geographical directions of tree) was significantly different in the first sampling date, but not in two other dates. Natural enemies of the aphid collected in this region were Exochomus nigromaculatus (Goeze), Chilocorus bipustulatus L., Sympherobius pygmaeus (Rambur), Anthocoris sp., Orius sp. and Chiracanthium sp. The species, E. nigromaculatus and S. pygmaeusâ are reported for the first time on P. passerinii. The two parasitoid species, Thaumatomyia elongatula (Becker) and Pachyneuron sp., are reported for the first time on this pest from Iran. Mean density of T. elongatula and S. pygmaeusâ were higher than other natural enemy species and placed in same LSD test class. Mean density of the parasitoid wasp, Pachyneuron sp., was less than other natural enemies

Distribution and New Host Plants of Seed Beetles (Col.: Chrysomelidae: Bruchinae) from Iran

This report is part of a national project for gathering and classifying the arthropod seed feeders in different provinces of Iran between 2008–2014. In this paper, nineteen host species with their areas of distribution are presented for twelve species of seed beetles (Chrysomelidae: Bruchinae). Most of the identified host plants (84%) belong to the family Fabaceae (Leguminosae). In addition, all known hosts for these beetles are discussed. The identified species in this study were confirmed by Dr. Alex Delobel in the Natural history Museum of Paris. The studied material is deposited in the arthropod collection of Research Institute of Forests and Rangelands

Unraveling the tripartite interactions among the woolly poplar aphid, its host tree, and their environment: a lead to improve the management of a major tree plantation pest?

Article en open accessInternational audienceKey message For an optimal deployment of poplar resistance to the gall-inducing aphid Phloeomyzus passerinii, a laboratory susceptibility assay has been developed. The nature of aphid–tree interactions during compatible and incompatible situations has been studied in detail. This should help at identifying specific resistance markers and at testing effects of site conditions on tree–pest interactions. Context P. passerinii is a major pest of poplar plantations in Europe, and the plantation of resistant poplar genotypes is regarded as the best long-term management strategy for this pest. This requires a sound knowledge of the interactions among the pest, its host and their environment. Aims Here, we review the recent advances aiming at developing an optimal deployment of host resistance versus P. passerinii. Results Investigations on aphid-host interactions demonstrated that P. passerinii induces pseudogalls within the bark of susceptible hosts. This results in a reduction of starch bark content during aphid outbreaks, which could be involved in tree death. The constitutive level of starch in the bark could be related to the tolerance level of trees. A susceptibility test has been designed for poplar genotypes, discriminating three categories of susceptibility depending on tree’s ability to totally or partially inhibit pseudogall induction. The test still has several limitations however. It neither takes into account the large level of individual genetic diversity of the aphid in France, nor the environmental modulation of tree resistance and tolerance, while water deficit and fertilization could potentially affect these parameters. Conclusion The hypotheses drawn regarding the processes leading to tree death or resistance should help at identifying resistance markers, and at testing effects of site conditions on tree–pest interactions