Effects of Two Plant Growth Regulators, Terpal-C and Cerone, on Freezing Tolerance and Winter Survival of Canola (Brassica napus L.)

One of the most attractive short-term possibilities for increasing freezing tolerance of winter crops may be the application of chemicals. This research was conducted to determine the effect of two plant growth regulators, Terpal-C and Cerone on freezing tolerance and winter survival of canola. Three cultivars were planted on the Michigan State University Agronomy Farm at East Lansing, MI. on Sept. 10, 1992 and 1993. Chemicals were applied to one-month-old plants when they reached the 5 leaf stage. Ion leakage tests for freezing tolerance were conducted before and after chemical treatment. Winter survival was evaluated by counting the plant standing in the fall and spring. Neither of the chemicals had any effect in increasing freezing tolerance and winter survival. Instead, one of the chemicals, Terpal-C. inhibited natural cold hardening.