Soybean cultivars and fumigation against Rotylenchulus reniformis in a commerce silt loam soil

Abstract

Reniform nematode (Rotylenchulus reniformis) is highly variable in reproduction and pathogenicity on soybean cultivars. The objectives of this research were to evaluate cultivars with various levels of resistance to this nematode and the impact of fumigation in a field with a Commerce silt loam soil previously planted with cotton. A field study was conducted from 2014-2016 with nine cultivars (three moderately resistant and six susceptible to reniform nematode) each year and two nematicide treatments (the fumigant 1,3-dichloropropene and a no-nematicide control) with six replications. Soil samples were collected at-planting and after harvest for nematode analysis. The fumigant significantly decreased populations of the nematode at the time of planting an average of 87% and after harvest by 59%. There were also significant differences with reniform nematode population density after harvest among the cultivars with the moderately resistant cultivars generally having the lowest populations. The fumigant did not result in significant yield increases in any year. Although there were significant differences in yield among the cultivars each year, there was no fumigant by cultivar interaction. Cultivars in 2014 and 2015 that were moderately resistance to reniform nematode provided a significant increase of 269 and 322.8 kg/ha, respectively over cultivars that were susceptible. These studies indicate that under the soil and environmental conditions present in a Commerce silt loam field, cultivar selection was more important than the use of a nematicide to manage reniform nematode.