Olfactory response of Myzus persicae (Homoptera: Aphididae) to volatiles from leek and chive: Potential for intercropping with sweet pepper

Abstract

Odour-mediated effects of leek Allium porum and chives Allium schoenoprasum (Alliaceae) on the host searching behaviour of the aphid Myzus persicae (Sulzer) (Homoptera: Aphididae) were studied. In an olfactometer, odour of the host plant sweet pepper Capsicum annuum L. (Solanaceae) was significantly attractive, whereas odour of chives was significantly repellent. Combined odour of sweet pepper and chives was neither attractive nor repellent. When sweet pepper plants were exposed to volatiles from chives for five days, their odour subsequently became repellent to M. persicae. An extract of leek plants was significantly repellent to aphids in the olfactometer, as were sweet pepper plants sprayed with this extract. Because both leek and chives can disrupt host finding by the aphid, both plants have potential for intercropping with sweet pepper. If successful in the field, such a system could bring economic benefits for farmers in the wet zone of Sri Lanka and other parts of the world.     

When is it biological control? A framework of definitions,mechanisms, and classifications

Journal of Pest Science - Biological control, or biocontrol, is the exploitation of living agents (incl. viruses) to combat pestilential organisms (incl. pathogens, pests, and weeds) for diverse...     

Correction to: When is it biological control? A framework of definitions,mechanisms, and classifications

Journal of Pest Science - A correction to this paper has been published: https://doi.org/10.1007/s10340-021-01386-z     

Aphid acceptance of Hordeum genotypes is affected by plant volatile exposure and is correlated with aphid growth

Nineteen genotypes of Hordeum vulgare (L.) were screened and characterized as partially resistant or susceptible regarding growth of the bird cherry—oat aphid (Rhopalosiphum padi L.). In a separate test, these same genotypes were treated with volatiles from undamaged plants of barley cultivar Alva. As a result of this treatment, aphid host acceptance (AHA) was significantly affected in seven genotypes, and the magnitude of the effect was positively correlated with aphid growth (AG) in the independent resistance screening test. Changes in AHA induced by volatiles from the same genotype as the volatile receiver were also positively correlated with AG. All the 19 genotypes were also tested as inducers with cultivar Kara as the receiver of volatiles. Five genotypes induced significant reductions in AHA of Kara. The results show that aphids are able to detect changes in responding plants induced by volatiles from another plant. Plant volatile interactions may thus be a component of induced resistance to aphids. These interactions could influence the results of experiments used to select for insect-resistant plants in plant breeding programmes, where normally plant genotypes are mixed at testing.