Identifying and evaluating plant feeding phytoseiids for pest control in orchard systems – a tricky business


Abstract: We have shown that Euseius species actively feed on plant tissue, raising the question whether these phytoseiids may be affected by cultivar as are their pest counterparts and whether cultivar could also affect intraguild predation (IGP). Recently we reported that the plant feeding Euseius species are more effective citrus rust mite Phyllocoptruta oleivora predators than the non-plant feeding species Amblyseius swirskii. Developing and integrating the use of resistant cultivars for pest control is an important tool in IPM. Resistance may be constitutive or induced and can be affected by environmental conditions such as light spectrum. In the field on pomelo, provisioned with windborne pollen from flowering cover crops, establishment of E. stipulatus was minimal whereas population levels of the naturally occurring IGP A. swirskii were high. In contrast on Shamouti, with the same pollen provisioning, populations of E. stipulatus, were higher than those of A. swirskii. Establishment of E. scutalis in both plots and in the seedling trial was nil and low, respectively. In the E. stipulatus seedling trial the levels of A. swirskii were substantially higher on pomelo than on Shamouti, whereas the populations of E. stipulatus were not affected by cultivar. UV affected mite establishment, where populations were highest without UV. Evidently IGP, cultivar and UV need to be considered when evaluating biocontrol under controlled and semi controlled conditions, regardless of whether the phytoseiids feed on the plant or not.Abstract only

Cookie Consent with Real Cookie Banner