Reference Report for IND81107997
Title: | Effects of row width and plant growth habit on Septoria glycines brown spot development and soybean yield |
Authors: | Pataky, J.K., Lim, S.J. |
Source: | Phytopath. 1981, 71:1051-1056 |
Abstract: | The effects of row width and soybean growth habit on the development of Septoria brown spot and on reductions of yield or seed weight due to brown spot were studied at two Illinois locations. In plots of artificially inoculated and naturally infected soybeans, the vertical progress of brown spot was greater for Elf, a determinate cultivar, than for Williams, an indeterminate cultivar. Brown spot severity and area-under-the-disease-progress-curve (AUDPC) were similar for both cultivars. Differences in disease severity among plots with 17-, 50-, and 75-cm row widths were not consistent although there was a trend toward greater brown spot infection at wider row widths. In inoculated plots, brown spot reduced yields from 12.9 to 20.8% for Elf and from 7.6 to 14.1% for Williams. The disease parameters that correlated best with yield reductions were disease severity at the R5 growth stage, brown spot vertical progress at the R6 growth stage, and AUDPC. Results indicate that planting soybeans in narrow rows will not increase brown spot; however, growing semidwarf determinate cultivars may increase losses due to this disease |