Studies on the practical use of one year stored pear pollens in the Nijisseiki pear culture

Abstract

The possibility of practical use of one year stored pear pollens for the artificial pollination of Nijisseiki pear was investigated in 1962-1965.
1. At the optimum storage condition in a home use electric refrigerator one year stored pear pollens of three varieties gave a germination of 80.3% for Chojuro, 67.4% for Okusankichi, and 85.0% for Yagumo, respectively. They were 5-10% lower than the germination rate of freshly collected pollens in the respective varieties.
2. As the result of artificial pollination of stored pollens in the field, more than 80% of the flowers developed into fruit having average 7 seeds per fruit when the pollens had more than 30% of germination rate. Also, there found no differences between stored and freshly collected pollens in the rate of fruit set, fruit development, and quality after harvest. It seemd that there was no trouble to use one year stored pollens in practical Nijisseiki pear culture.
3. It was recognizied that one year stored pollens collected from vigorous tree gave a germination of more than 70% when they were put into the refrigerator within 24 hours after collected and were kept at 5°C and 30-50% relative humidity.