Population dynamics and spatial distribution of Columbia lance nematode in cotton

Abstract

Hoplolaimus columbus, Columbia lance nematode (CLN), can cause severe stunting and considerable yield losses in cotton. A three-year field study was conducted in South Carolina with the purpose of examining the population dynamics and spatial distribution patterns of CLN as influenced by soil texture, the presence of Rotylenchulus reniformis, reniform nematode (RN), and a cotton–corn–soybean rotation scheme. Four plots with different soil textures inferred by soil electrical conductivity were sampled at plant and at harvest for each crop. Population densities of CLN were aggregated and the host plant did not affect the pattern of spatial distribution. Columbia lance nematode and RN were found in spatially distinct areas in the field influenced by differences in soil texture. Columbia lance nematode was mainly found in areas with high sand content (above 75%) and RN in areas with 60–65% sand content. Therefore, depending on the sand content, whenever there are concomitant infestations of CLN and RN in a field, only one species is likely to be the key pest. Knowledge of the distribution patterns of CLN is essential for selecting sampling strategies and for site-specific management.