Search results for "Aphis gossypii"
showing 4 items of 4 documents
Olfactory response of two aphid parasitoids, Lysiphlebus testaceipes and Aphidius colemani, to aphid-infested plants from a distance
2004
The role of volatile stimuli in the host-searching behaviour of the two parasitoid species Lysiphlebus testaceipes Cresson and Aphidius colemani Viereck (Hymenoptera: Braconidae) was studied in relation to the host Aphis gossypii Glover (Homoptera: Aphididae) on cucumber plants, Cucumis sativa L. (Cucurbitaceae). Experiments were carried out in the laboratory in a wind tunnel, exposing individual parasitoids to signals from three sources simultaneously: (1) a complex of cucumber plants, Cucumis sativa , and A. gossypii ; (2) uninfested cucumber plants; and (3) dummy cardboard plants. The flight response of the female parasitoids was considered oriented when they landed on plants and non-ori…
Species composition and richness of aphid parasitoid wasps in cotton fields in northern China
2017
AbstractThe cotton aphid, Aphis gossypii (Hemiptera: Aphididae), is a serious pest of cotton across the globe, particularly in the cotton agroecosystems of northern China. Parasitic wasps are deemed to be important natural enemies of A. gossypii, but limited information exists about their species composition, richness and seasonal dynamics in northern China. In this study, we combine sampling over a broad geographical area with intensive field trials over the course of three cropping seasons to describe parasitoid-hyperparasitoid communities in cotton crops. We delineate a speciose complex of primary parasitoids and hyperparasitoids associated with A. gossypii. Over 90% of the primary paras…
Ecology of the aphid pests of protected pepper crops and their parasitoids
2011
Abstract Myzus persicae, Macrosiphum euphorbiae, Aphis gossypii and Aulacorthum solani (Homoptera: Aphididae) are principal pests of protected pepper crops in southeastern Spain. Our goal was to determine the incidence of aphids on pepper crops and the role of vegetation surrounding greenhouses as a source of aphids and their parasitoids. The population dynamics were followed in six commercial greenhouses during 3 years. Another 82 greenhouses and their surrounding vegetation were surveyed occasionally. Myzus persicae had the highest incidence in pepper greenhouses followed by M. euphorbiae and A. solani. Parasitism of all aphid species in greenhouses was low, Aphidius matricariae and Aphid…
Incidence and epidemiology of Citrus tristeza virus in the Valencian Community of Spain
2000
Abstract The first outbreak of citrus tristeza disease in Spain caused by Citrus tristeza virus (CTV) was recorded in 1957 in the Valencian Community (VC). In total c. 40 million trees, mainly of sweet orange and mandarin grafted on sour orange rootstocks, declined due to CTV. Large-scale surveys in different municipalities of the VC indicated that the disease spread very fast. Incidence increased from 11% in 1989 to 53% in 1998. Toxoptera aurantii and Aphis spiraecola (inefficient aphid vectors of CTV) predominated before 1985–87. Since then the relatively efficient vector Aphis gossypii has become dominant and induced an epidemic that has been modelled. The large number of A.gossypii that…