Ecological Interaction in the Proliferation of Phytoparasitic Nematodes in Coffee var. Typica

Abstract

Phytoparasitic nematodes are a common problem in coffee production worldwide. In Peru, the proliferation of phytoparasitic nematodes in Coffea arabica L. var. Typica has negative impacts on coffee production and huge economic losses. The objective of this study was to determine the ecological interactions that influence the proliferation of phytoparasitic nematodes in C. arabica var. Typica in Quillabamba, Cusco, Peru. The density of phytoparasitic nematodes in the soil and root was evaluated using the modified Baermann channel method. Identification of genera and species of phytoparasitic nematodes was carried out in the different samples, based on descriptions and taxonomic keys. Physical and chemical parameters of the soil were evaluated. Principal component analysis (PCA) and a correlation network were employed to distribute the different species of nematodes. The variables soil texture, organic matter, pH, altitude, temperature and humidity were used. During the sampling, several genera of plant-parasitic nematodes were identified in addition to various categories of nematodes. Meloidogyne exigua, Pratylenchus coffeae, Allotrichodorus longispiculis and Helicotylenchus longicaudatus are among the specific species of nematodes identified. The genus with the highest incidence was Meloidogyne spp. with 77.3% in soil and 96% in roots, reaching an average density of 340 nematodes in 100 g of soil and 368 nematodes in 1 g of roots. The PCA results show that 63.7% of the variability of the data is retained in the first two components. PCA shows that the sampled areas were differentiated and grouped with the evaluated characteristics, while the nematodes overlap in the representation of the analysis, thus making it difficult to select them. Pearson’s correlation showed a negative correlation between altitude and soil nematode density (−0.22), suggesting that conditions at higher altitudes may be more unfavorable for nematode growth. In addition, a positive correlation was found between soil pH and organic matter (0.93, p < 0.001) and may influence nematode density. The factors that influence the density of nematodes in the soil and plant roots are multiple and complex, and their understanding is essential for the success of coffee production. The finding of the current study may be useful in the development of sustainable strategies for managing nematodes in coffee network production.