Influence of cabbage resistance and colour upon the diamondback moth and its parasitoid Oomyzus sokolowskii |
| |
Authors: | Felipe Colares Christian S A Silva‐Torres Jorge B Torres Eduardo M Barros Angelo Pallini |
| |
Affiliation: | 1. Departamento de Agronomia – Entomologia, Universidade Federal Rural de Pernambuco, , Recife, PE, 52171‐900 Brazil;2. Departamento de Biologia Animal, Universidade Federal de Vi?osa (UFV), , Vi?osa, MG, 36570‐000 Brazil |
| |
Abstract: | Host plant resistance and biological control are vital integrated pest management tools against the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), but to date no study has investigated this system including the DBM parasitoid Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae). We examined oviposition and development of P. xylostella exposed to two commercial cabbage cultivars (green ‘Chato de quintal’ and red ‘Roxo’) and possible effects upon O. sokolowskii. Under free‐choice tests, DBM females laid significantly more eggs on plants of the green cabbage, even though several population growth parameters showed that DBM developed better on the red cabbage. Furthermore, a laboratory free‐choice test with artificially green‐ and red‐painted kale leaf discs demonstrated a similar oviposition preference pattern, with green colour being preferred over red colour. The preference was apparently visually mediated; olfactometer tests showed similar attraction of moths to both green and red cultivars in choice and non‐choice tests. Host plant cultivar had no statistically significant effect on female parasitoid behaviour towards DBM larvae, nor on parasitoid numbers or longevity. Moreover, wasps parasitizing DBM larvae reared on the green cultivar developed more quickly and in larger numbers per parasitized larva. Thus, feeding on green cabbage rather than red does not hinder, and potentially even enhances, control of DBM by O. sokolowskii. On a practical level, these results suggest that intercalating green cabbage cultivars as a trap crop might help protect more profitable red cultivars in growing fields. |
| |
Keywords: | oviposition preference integrated pest management IPM biological control host plant resistance
Plutella xylostella
Lepidoptera Plutellidae Hymenoptera Eulophidae
Brassica oleracea
|
|
|