Interference of Soybean,<i>Glycine max</i>, Cultivars with Sicklepod,<i>Cassia obtusifolia</i>

Abstract

Greenhouse and field experiments were conducted at Athens, GA, during 1984 and 1985 to evaluate the interference of several soybean cultivars with sicklepod. The 12 soybean cultivats evaluated in the field were commonly used from 1907 to the present. No correlation of soybean cultivar maturity group or date of introduction with interference on sicklepod was observed. ‘Essex’ and ‘Bragg’ soybean reduced sicklepod dry weight in the field; however, only Essex was unaffected by sicklepod. In the greenhouse experiments, root and shoot growth of sicklepod was less than the cultivars ‘CNS', ‘Peking’, and ‘Forrest’. Sicklepod produced the least above- and below-ground growth while ‘CNS' produced the most of the three cultivars. When grown together, the combined total root growth of each cultivar plus sicklepod was less than calculated expected values. The genetic development of soybean cultivars with improved tolerance to sicklepod infestations possibly could reduce weed control inputs.