Description

Summary: A field research trial was conducted to investigate the effects of a cover crop (Arachis pintoi) on abundances of an aphid (Aphis craccivora), one of its ladybird beetle predators (Menochilus sexmaculatus), predatory soil-dwelling arthropods (Formicidae, Gryllidae and Araneida), and on yield of yard-long bean (Vigna sesquipedalis). This field trial was carried out from February to May 2008 in Hambaro Village, Nanggung Subdistrict, Bogor District, West Java, Indonesia, while the laboratory analysis was conducted in the Insect Ecology Laboratory, Plant Protection Department, College of Agriculture, Bogor Agricultural University, Indonesia.

Results showed that the A. pintoi cover crop had no effect on abundances of the aphid, A. craccivora, or the ladybird beetle, M. sexmaculatus, on yard-long bean. However, abundances of several groups of soil-dwelling arthropods tended to be higher in the plots with the cover crop than in those without. There was also a tendency for the yard-long bean yields to be lower in the plots with the cover crop than in those without. The authors conclude that results from this experiment have not demonstrated that the A. pintoi cover crop provides ecological benefits in terms of reducing pest numbers, or economic benefits by raising yard-long bean yields. It is recommended that the trial be repeated at least one more season. To reduce competition for nutrients between the yard-long bean and the cover crop, it is recommended that the cover crop be cleared from the area around the yard-long bean roots. It would also be advisable to measure the long-term effects on nutrient availability and soil conservation from the presence of the cover crop.