ARS | Publication request: DYNAMICS OF NEMATODE POPULATIONS IN CACAO GROWN UNDER TRADIONALLY SYSTEM OF MANAGEMENT IN PERUVIAN AMAZON

Submitted to: Biodiversity of Soil International Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: September 24, 2007
Publication Date: September 29, 2007
Citation: Arevalo, G.E., Zuniga, C.L., Baligar, V.C., Canto, S.M. 2007. Dynamics of nematode populations in cacao grown under tradionally system of management in peruvian amazon. Biodiversity of Soil International Conference Proceedings. 9.29.2007.

Technical Abstract: Nature of crops and management systems greatly influences population dynamics of parasitic and nonparasitic nematodes in soil. An experiment was undertaken at Tropical Crop Research institute (ICT), Tarapoto, Peru to assess the population dynamics of nematodes in a Cocoa (Theobroma cacao L.)-Banana (Musa spp.)-Guaba (Inga edulis) cropping system. The banana was used as a temporary shade crop and Guaba was planted as permanent shade crop. The objectives of this study were to determine the population dynamics of nematodes in different soil depths (0-20, 20-40, 40-60 cm) and to evaluate their relationships to soil edaphic and climatic conditions. The experiment was carried out from 1999 to 2004. Cobb’s modified method was used to extract the nematodes. At all soil depths, the nematode population (parasitic and nonparasitic) in this system of management increased through the years from 1999 to 2004 (125 to 798.2 nematodes/100g of soil). The soil depth had profound effects on nematode population, the highest density of nematodes was observed in the first 20 cm of soil depth (261.3 nematodes/100g soil). Population of both parasitic and nonparasitic nematodes declined considerably with soil depth. The most frequent parasitic nematodes, associated with this system of cropping, were Meloidogyne, Helicotylenchus and Pratylenchus, while the nonparasitic nematodeswere Dorylaimida and Rhabditida. Soil edaphic factors and prevailing high average aerial temperature of 26°C have an effect on the differences in nematode populations at various soil depths. The soil edaphic conditions to the depth 0-20cm were sandy-loam texture with 60% sand, low pH (4.4 to4.6), and low content of organic matter (<1.5%), appears to have favorable for higher nematode development in the surface soil layer.