The role of Crambe abyssinica in the control of Heterodera glycines (Thylenchida: Heteroidae)

The soybean cyst nematode (SCN), Heterodera glycines, is present in more than 150 municipalities in Brazil, and the long persistence of the cysts in the soil combined with the severe degree of parasitism induces high soybean production losses. The objective of this study was to evaluate the biofumigant effect of Crambe abyssinica on the SCN population in the second soybean crop season. The experiment was conducted on a rural property whose soil was naturally infested with SCN. Crambe abyssinica was planted in the second crop season following harvest, and in the subsequent crop season, 4 soybean varieties, 2 resistant and 2 susceptible to SCN, were planted. The nematode population was evaluated every month for 90 days after planting. In the second crop season, when C. abyssinica was in the field, there was a significant decrease in the number of adult SCN females and cysts. During the 90-day period after C. abyssinica cultivation, when plant residues were incorporated into the soil and the area was planted with soybeans, both the number of adult SCN females / 10 g roots and the number of cysts decreased. This result indicates that C. abyssinica reduced the nematode population during its time in the field. Key words: Crambe, Glycine max, soybean nematode cyst, culture control.