Compatibility of a Melia azaderach extract with Eriopis connexa (Coleoptera: Coccinellidae)”.

HARAMBOURE, MARINA; MIRANDE, LUCIANA; SMAGGHE, GUY; PINEDA, SAMUEL; SCHNEIDER, MARCELA INÉS

Ghent-Belgium

Simposio; 62nd International Symposium on Crop Protection; 2010

Ghent University

The Integrated Pest Management (IPM) premises claim to a joint use of beneficial organisms (parasitoids and predators) and selective pesticides. Botanical pesticides are being considered as selective pesticides. During the last 20 yr of the 20th century, the plant family Meliaceae was identified as a promising source of compounds with insect-control properties. The Chinaberry tree, Melia azaderach L., is a deciduous tree native to Persia, India, and China, but has been cultivated in many countries including Africa, Australia, and the Americas. It is a source of tetranortriterpenoid compounds called meliatoxins, which have similar structures and insecticidal activities than azadirachtin. Evaluation of the Melia extracts toxicity should be the first step for the joint use of these extracts and natural enemies for pest control according to IPM premises. Eriopis connexa L (Coleoptera: Coccinelidae) is a native predator from Neotropical Region. It is a beneficial organism associated to several agroecosystems, feeding on soft-bodies pest such as aphids, whiteflies and trips. In horticultural crops, it has been observed feeding on worldwide important pest such as Bemisia tabaci Gennadius (Heteroptera: Aleyrodeidae) and Myzus persicae L. (Heteroptera: Aphididae), both of them considered as viruses vectors. The objective of this work was to evaluate the side-effects of M. azaderach (Meliaceas) extract on eggs, larvae and adults of Eriopis connexa. Unripe fruits extracts were employed (1% w.w-1, obtained by the CEPROCOR, Cordoba-Argentina) for ecotoxicological bioassays. The exposure way was by inmersion in eggs and by ingestion of drinking water for adults’ treatment. The botanical extract solutions were prepared using distilled water as solvent and a tensoactive (Tween 20®) for topical application. The bioassays were carried out in the laboratory under controlled conditions: 23±0.5 °C temperature, 75±5% RH and 16:8 L:D of photoperiod. Hatching, development time, adult emergence, pre-oviposition period, fecundity and fertility were evaluated as endpoints. None detrimental effects were observed in treated organisms irrespective of the exposure way and development stage. According to these preliminary results, M. azaderach fruit extracts could be compatible with E. connexa for pest control. However, future studies should be addressed to conclude about its toxicity on beneficial organisms.