Evaluation of perennial Glycine species for resistance to M. incognita

The Bartlett tests for homogeneity of variance for eggs per gram of root and gall index were not significant (P> 0.05) between trials, so data were pooled for analysis (Table 2). Our results demonstrate substantial variation in nematode reproduction and gall index among perennial Glycine accessions (Table 2 and Fig. 1). The susceptible check soybean cv. Pickett 71 was not significantly different from the resistant check cv. Forrest in eggs per gram of root but had a significantly greater gall index (Table 2; Fig. 1A, B). Ten perennial Glycine accessions (PIs 373990, 339655, 440932, 440960, 441001, 446974, 446983, 505197, 509472, and 559300) had significantly fewer eggs per gram of root than the susceptible check cv. Pickett 71, and fewer root galls (Fig. 1 C-F). Among the accessions, all but PI 440960 had significantly fewer eggs per gram of root than the resistant check cv. Forrest. All the tested PIs except PIs 573045 and 559298 had lower gall indices than cv. Pickett 71. Only G. tomentella PIs 339655 and 446983 had a significantly lower gall index (Fig. 1C) than cv. Forrest.