Tannic Acid Effects on Hatching of Heterodera glycines in Vitro

Effects of tannic acid on hatching of Heterodera glycines eggs were determined in vitro using three batches of eggs obtained from greenhouse cultures in Florida or from naturally infested field soil in Minnesota. A quadratic model fits the percentage egg hatch. Hatch increased with increasing tannic acid concentrations from 0 to about 39 mg/liter, then declined with further increases in concentration. Tannic acid did not induce hatching of dormant eggs obtained from the field.