Effect of grafting and nematicide treatments on damage by root-lesion nematodes (Pratylenchus spp.) to Coffea arabica L. in Guatemala

Root-lesion nemattodes, Pratylenchus spp., are among the pests with the greatest negative impact on the economy of coffee production in Guatemala. A field experiment was undertaken in southwest Guatemala to assess damage due to a root-lesion nematode and to compare two methods of management: grafting onto Coffea canephora Pierre, 1897, and nematicide treatments (terbufos). The experiment was carried out for five years, and included the first three harvests. Root population densities of nematodes, coffee berry yield losses, and plant mortality rates were highest on ungrafted C. arabica, confirming its high degree of vulnerability to this root-lesion nematode population. Grafting onto C. canephora provided efficient control of populations of root-lesion nematodes and resulted in significantly greater yields compared to ungrafted plants. Nematicide treatments suppressed populations of this root-lesion nematodes only until the second year after planting. This was sufficient to significantly reduce rates of plant mortality in ungrafted plants. However, nematicide treatments did not result in significant Increase of yield regardless of the rootstocks used. This work also provided evidence that growing grafted coffee trees under shade may be a beneficial tactic for managing these root-lesion nematodes.