Potassium leaching test in evaluation of popcorn seed vigor

The search for tests that offer fast and reliable information on the physiological potential of seeds is of fundamental importance for quality control programs. The aim of this study was to evaluate the efficiency of the potassium leaching test in identification of different vigor levels of popcorn seed lots. Five seed lots of the hybrids AP8203 and AP4512 were tested for moisture content, and physiological quality was evaluated by tests of germination, first count of germination, and seedling emergence in the field. These results were compared to variations in the potassium leaching test (temperatures of 25 degrees C and 30 degrees C, volumes of 50 mL and 75 mL of water, fifty and one hundred seeds, and periods of 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 4 h and 5 h). Results showed that the potassium leaching test is efficient in separating the popcorn seed lots regarding physiological potential, and the most adequate conditions for this test are the use of fifty seeds with 50 mLof water for two hours at 30 degrees C.