Efecto de la sombra y del manejo del café sobre la dinámica poblacional de Hypothenemus hampei Ferrari en frutos nuevos y remanentes en Turrialba

Sanchez Gonzalez Esteban. 2011. Efecto de la sombra y del manejo del café sobre la dinámica poblacional de Hypothenemus hampei Ferrari en frutos nuevos y remanentes en Turrialba. Turrialba : CATIE, 106 p. Tesis Magister : Scientiae. Agricultura ecologica : Centro Agronomico Tropical de Investigacion y Ensenanza

Titre anglais : Identification of the variation sources affecting coffee quality (coffea arabica) in El Paraíso and Alauca municipalities, Honduras

Résumé : The effects of shade on the population dynamics of Hypothenemus hampei are controversial. Shade can directly affect H. hampei lyfe cycle through the microclimate, or indirectly by altering the fruit phenology that affects the availability of habitat and ecological niche. For its part, the conventional management with insecticide for H. hampei control is a practice that increases the risk of environmental degradation, while the effects of management aimed at increasing selective diversity use, as Beauveria bassiana, can be an acceptable strategy under shade conditions. The objective of this study was to clarify the effects of shade and coffee tree management on the populations of H. hampei. The research was carried out in Turrialba, Costa Rica, at an altitude of 600 m and average annual rainfall of 2700 mm. We studied three levels of exposure to light (full sun, regular shade of Erythrina poeppigiana, dense shade of E. poeppigiana and Abarema idiopoda) and three management intensities (organic with B. bassiana, conventional with insecticide, and conventional insecticide-free). We studied the effect of different combinations of these factors on (i) the population of H. hampei in green fruits and fruits remaining from the harvest, (ii) the number of bored green fruits from february to september 2010 (iii) and the composition of fruit populations over time. We monitored the microclimate in two extreme conditions of sun and shade. The dense shade level caused significant differences (F1, 68=5.08, p<0.0274) in populations of alive adult females of H. hampei in ripe fruits 1.91 ± 0.31 females / fruit with respect to full sun 1.20 ± 0.23 females / fruit, while alive females in dry fruits remaining in the coffee tree increased significantly (F1, 63=10.17, p<0.0022), p <0.0022) from 4.01 ± 1.63 females / fruit in full sun to 11.12 ± 1.63 females / fruit with medium shade. This can be explained by the favorable microclimatic conditions under shade, preventing the rapid dehydration of fruits and favoring the insect's life cycle. For example, we observed at noon in days with rainfall ? 5 mm, lower temperatures and relative humidities, 3 ºC and 12 % respectively, under shade as compared to full sun. In addition, we observed an advanced ripening at full sun exposure compared with dense shade. In July-August, at full sun exposure, 11 % of the fruits suitable to coffee berry borer were ripening fruit, whereas only 3 % of these fruits were found under dense shade. These ripening fruits were proportionally more attacked than green fruits, as they comprised 29 % of the bored fruits at full sun, and 9 % under dense shade. Regarding the effect of agricultural management on H. hampei we observed 11.12 ± 1.63 alive adult females / dry fruit in the conventional insecticide-free management, a number significantly higher (F1, 63=12.10, p<0.0009) than the number observed under the organic management with B. bassiana (3.36 ± 1.63 alive adult females / dry fruit. The results indicate antagonistic effects of shade on H. hampei. In one side, shade favors coffee berry borer multiplication inside the fruits, but in the other side, the more palatable fruits are more abundant at full sun exposure. These effects could explain the spatial distribution of the insect at plot and micro-landscape scales. H. hampei could migrate from the shaded areas, where it multiplies better in the interseason, to the sunny area where the most palatable fruits of the new crop can be encountered sooner and in greater amounts, and then gradually spreads to the rest of the plantation or the micro-landscape. This suggests the possibility of implementing control measures targeted to those sunny areas. It was also confirmed that, shaded coffee plantations are a favorable habitat for the enhancement of the suppressive effects of B. bassiana on H. hampei populations, which is useful in order to develop management strategies more effective and environmentally friendly.

Mots-clés Agrovoc : Coffea, Hypothenemus hampei, agroforesterie

Mots-clés géographiques Agrovoc : Costa Rica

Classification Agris : H10 - Ravageurs des plantes
F08 - Systèmes et modes de culture
F62 - Physiologie végétale - Croissance et développement

Auteurs et affiliations

• Sanchez Gonzalez Esteban, CATIE (CRI)

Source : Cirad - Agritrop (https://agritrop.cirad.fr/562215/)

Métriques

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