Hymenopterous Parasitoids of Agromyzid Leafminers（Diptera: Agromyzidae）on Leaves and Flowers of <i>Phacelia tanacetifolia</i> in Chiba Pref., Japan and Potential of <i>P. tanacetifolia</i> as a Banker Plant or Insectary Plant to Control <i>Liriomyza chinensis</i> （Diptera: Agromyzidae）

Abstract

Phacelia tanacetifoliaBentham is known worldwide as a kind of insectary plant and is used in Japan as a green manure crop before Welsh onion planting. To explore the possibility of using P. tanacetifolia as a banker plant or an insectary plant for parasitoids of Liriomyza chinensis Kato, we investigated the seasonal abundance of agromyzid leafminers and their hymenopterous parasitoids on infested leaves and blooming flowers of P. tanacetifolia collected in Chiba Pref., Japan, in 2009Japan, in , 2010Japan, in , and 2012. We also investigated longevity increase in Diglyphus isaea Walker adults with a blooming P. tanacetifolia plant in the laboratory. Almost all agromyzid leafminers reared from leaves were Chromatomyia horticola Goureau . Twenty-one parasitoid species including seven species reported from L. chinensis mines by different authors in Japan were reared from leaves, and nine species including eight species reared from leaves were caught on flowers. The most abundant parasitoid species was D. isaea. In this study, Diglyphus crassinervis Erdös was reared from C. horticola for the first time in Japan. The longevity of D. isaea adults provided with a blooming plant and water was about 18 days at 24 C with a 16L : 8D photoperiod. The log-rank test, used to compare survival curves from the 2 treatments; with and without blooming P. tanacetifolia plant, showed a statistically significant difference between treatments. These results suggest that P. tanacetifolia has potential as a banker plant or insectary plant for parasitoids to control L. chinensis in Welsh onion fields.

Potential for biological control of the vegetable leafminer, Liriomyza sativae (Diptera: Agromyzidae), in Australia with parasitoid wasps

“…() found that flowering strips, with Phacelia tanacetifolia as the dominant component of the planting mixture, promoted parasitism of ectoparasitoids over endoparasitoids of L. huidobrensis attacking lettuce crops in Italy, but there was no reduction in density of agromyzids. Oida & Kawana () used P. tanacetifolia as a banker plant to improve parasitism of L. chinensis in field‐grown onions; the agromyzid Chromatomyia horticola colonised the banker plant naturally and provided a host for parasitoids but did not attack the onions, while the banker plant also acted as an insectary plant for feeding parasitoids emerging from C. horticola . In Argentina, 13 of the 19 parasitoid species attacking Liriomyza commelinae (Frost) on Commelina erecta also attacked L. huidobrensis in the region (Fenoglio & Salvo ).…”