Field evaluation of early maturity group IV soybean cultivars for resistance to southern stem canker, 2007

摘要

The susceptibility of 57 very early maturity group IV soybean cultivars to stem canker was evaluated in a trial at Stoneville, MS. Soybean cultivars were planted in sandy loam soil on 27 Apr 07 at a rate of 10 seed per row ft in a randomized completeblock design with four replications. Plots were one row wide, 13.3 in. spacing, and 20 ft long. The first 12 plants of each plot were inoculated with Diaporthe phaseolorum var. meridionalis by inserting infested toothpicks in the upper 1/3 of the plant on 31 May 07. Disease resistance was rated on 3 Aug 07 based on a 1 to 5 rating scale where 1 = resistant, 2 = moderately resistant, 3 = moderately susceptible, 4 = susceptible, and 5 = very susceptible. Disease rating was reported as an average of four.