FIELD ASSESSMENT OF DIFFERENT SAMPLING STRATEGIES FOR COFFEE PLANTATIONS PARASITIZED BY <I>MELOIDOGYNE EXIGUA</I>

Abstract

Souza, R. M., A. R. Volpato, and A. P. Viana. 2007. Field assessment of different sampling strategies for coffee plantations parasitized by Meloidogyne exigua. Nematropica 37:345-355. To this date, there has been no assessment of strategies for quantitative sampling of Meloidogyne exigua. This imposes a major obstacle for realistic estimation of nematode population levels, establishment of damage thresholds, and improvement of the decision process for nematode management in coffee plantations. In this work, a commercial coffee plantation naturally infested by M. exigua was sampled for two years for comparison of different sampling core locations and J2- and root gallingrelated epidemiological variables. The sampling strategy primarily used by nematologists and agricultural workers-sampling near the edge of the coffee canopy to quantify second-stage juveniles in the soil-was revealed as inadequate for assessment of M. exigua populations. The best strategy for this nematode is to quantify the number of root galls/5 g of roots obtained from sampling cores located under the canopy, at the depth of 0-25 cm.