Kankonda O. M., Akaibe B. D., Musyoka B., Bruce Y. A., Le Rü Bruno. (2017). Disturbance of the rainforest has the potential to enhance egg parasitism of lepidopteran noctuid stemborers in Kisangani, DR Congo. African Journal of Ecology, 55 (3), p. 328-341. ISSN 0141-6707.
Titre du document
Disturbance of the rainforest has the potential to enhance egg parasitism of lepidopteran noctuid stemborers in Kisangani, DR Congo
Kankonda O. M., Akaibe B. D., Musyoka B., Bruce Y. A., Le Rü Bruno
Source
African Journal of Ecology, 2017,
55 (3), p. 328-341 ISSN 0141-6707
Landscape context influences population dynamics of insects and impacts biological processes within communities. It was expected that anthropogenic disturbances of the rainforest landscape in DR Congo would lead to a decreased level of noctuid stemborer egg parasitism as a consequence of a decoupling between stemborers and their naturally occurring parasitoids through dispersal. To test this hypothesis, noctuid egg batches were collected in maize fields along an anthropogenic disturbance gradient to assess change in the rates of eggs parasitism and maize plant infestation with noctuid egg batches. Our results showed that, in contrast to what was initially expected, egg parasitism increased from less to highly disturbed landscape whereas maize infestation had an inverse tendency. Discovery efficiency and mean egg parasitism were 1.416 and 1.392 times higher, respectively, in the most than in the less disturbed landscape. The numbers of eggs and egg batches per 100 maize plants were 0.55 times and 0.532 times the value in the less disturbed landscape, suggesting a dilution of the stemborer population within a large habitat patch encompassing cultivated fields and the surrounding wild host plants. It was concluded that the presence of suitable host plants enhances noctuid stemborers egg parasitism in adjacent maize fields.
Plan de classement
Sciences du monde végétal [076]
;
Etudes, transformation, conservation du milieu naturel [082]
