PLANT ROW AND SOIL FACTORS INFLUENCING THE MICROSPATIAL PATTERNS OF PLANT-PARASITIC NEMATODES ON SUGARCANE IN MARTINIQUE

This study compares the microdistribution of plant-parasitic nematodes and sugarcane roots in relation to the row and some soil parameters o n a ferrisol characterized by three degrees of hillock levelling. Soil and root samples were collected on a grid located between two rows of sugarcane. In the most levelled location, where carbon, nitrogen and potassium contents were the poorest, Pratylenchus zeae presented a spa tial pattern related to the row. This was also observed with Helicotyl enchus erythrinae in the three locations. On the contrary, Criconemell a onoensis did not show a marked spatial pattern related to the row or root quantity in any of the situations. Hemicriconemoides cocophillus appeared to be distributed parallel to sugarcane rows in the directio n of the slope. Spatial patterns were figured by graphical displays an d analyzed using semi-variograms to confirm and characterize the obser ved patterns. The use of cross semi-variograms showed antagonistic dis tributions between C. onoensis and the other species which were more p rominent in the levelled locations. In respect to hillock levelling in tensity leading to variations of soil parameters, micro-spatial patter ns and interactions among plant parasitic nematodes vary quantitativel y and qualitatively.