Publications des scientifiques de l'IRD

Mwalusepo S., Tonnang H. E. Z., Massawe E. S., Okuku G. O., Khadioli N., Johansson T., Calatayud Paul-André, Le Rü Bruno. (2015). Predicting the impact of temperature change on the future distribution of maize stem borers and their natural enemies along east african mountain gradients using phenology models. Plos One, 10 (6), p. e0130427 [23 p.]. ISSN 1932-6203.

Titre du document
Predicting the impact of temperature change on the future distribution of maize stem borers and their natural enemies along east african mountain gradients using phenology models
Année de publication
2015
Type de document
Article référencé dans le Web of Science WOS:000356329900172
Auteurs
Mwalusepo S., Tonnang H. E. Z., Massawe E. S., Okuku G. O., Khadioli N., Johansson T., Calatayud Paul-André, Le Rü Bruno
Source
Plos One, 2015, 10 (6), p. e0130427 [23 p.] ISSN 1932-6203
Lepidopteran stem borers are among the most important pests of maize in East Africa. The objective of the present study was to predict the impact of temperature change on the distribution and abundance of the crambid Chilo partellus, the noctuid Busseola fusca, and their larval parasitoids Cotesia flavipes and Cotesia sesamiae at local scale along Kilimanjaro and Taita Hills gradients in Tanzania and Kenya, respectively. Temperature-dependent phenology models of pests and parasitoids were used in a geographic information system for mapping. The three risk indices namely establishment, generation, and activity indices were computed using current temperature data record from local weather stations and future (i.e., 2055) climatic condition based on downscaled climate change data from the AFRICLIM database. The calculations were carried out using index interpolator, a sub-module of the Insect Life Cycle Modeling (ILCYM) software. Thin plate algorithm was used for interpolation of the indices. Our study confirmed that temperature was a key factor explaining the distribution of stem borers and their natural enemies but other climatic factors and factors related to the top-down regulation of pests by parasitoids (host-parasitoid synchrony) also played a role. Results based on temperature only indicated a worsening of stem borer impact on maize production along the two East African mountain gradients studied. This was attributed to three main changes occurring simultaneously: (1) range expansion of the lowland species C. partellus in areas above 1200 m.a.s.l.; (2) increase of the number of pest generations across all altitudes, thus by 2055 damage by both pests will increase in the most productive maize zones of both transects; (3) disruption of the geographical distribution of pests and their larval parasitoids will cause an improvement of biological control at altitude below 1200 m.a.s.l. and a deterioration above 1200 m.a.s.l. The predicted increase in pest activity will significantly increase maize yield losses in all agro-ecological zones across both transects but to a much greater extent in lower areas.
Plan de classement
Sciences du monde végétal [076] ; Sciences du monde animal [080]
Description Géographique
AFRIQUE DE L'EST ; TANZANIE ; KENYA
Localisation
Fonds IRD [F B010064727]
Identifiant IRD
fdi:010064727
Contact