Cold Test and Saturated Cold Test Reliability for Testing Carryover Corn Seed Treated with Seed-applied Insecticides
Goggi, A. Susana
The cold test germination percentage of carryover seed corn lots treated with a seed-applied insecticide (SAI) can be below the seed industry's sale standard. However, the same seed lots have good emergence (Bo to 90%) when planted in the field. The objectives of this study were to 1) evaluate the extent of cold test germination differences between carryover seed lots treated with fungicide + SAI or fungicide-only; 2) determine if an alternative preparation can be made to a seed lot prior to the cold test and the saturated cold test; and 3) address the accuracy of the conventional cold versus the saturated cold testing method in predicting field emergence. Nineteen seed lots treated with fungicide-only or fungicide + SAI were tested in the laboratory and the field. The cold test germination percentage of carryover seed lots treated with fungicide + SAI was lower than fungicide-only treated seed. When the treatments were removed with Tween 20, the cold test germination of the fungicide+ SAI-treated seed was not significantly different from the fungicide-only treated control. The cold test of fungicide-only treated and fungicide+ SAI-treated seed correctly estimated emergence under all field conditions. After the fungicide + SAI seed treatment was removed, the saturated cold test accurately predicted field emergence under "poor" field conditions but underestimated field emergence under "average" or "good" field conditions. Removing the fungicide + SAI treatment before conducting the cold test may help seed companies better predict field emergence of the seed lots.
This article is published as Goggi, A. Susana, Daniel Curry, and Jeff Daniels. "Cold test and saturated cold test reliability for testing carryover corn seed treated with seed-applied insecticides." Seed Technology 31 (2009): 7-20. Posted with permission.