Sweet potato Breeding by Seeds, with Artificial Induction of Blooming

Abstract

In order to begin the breeding work with sweet potato in the district where no flowering of the plant naturally occurs methods were studied to induce it to bloom and set seed, at the Agricultural Experiment station, Government General of Chosen, in 1937 and 1938. It was found that most of the sweet potato varieties were quite successful to flower under the conditions of short-day-photoperiod controlled at 8 or 10 hours. After natural polination of the flowers 127 mature seed pods were harvested in 1937, and by artificial crossing in 27 varieties of the plant a total of over 2, 000 of pods was produced in 1938., a few examples of the results being as flollows : [table] In the variety sitihuku, on an average of five plants, over 100 pods were produced on a single plant, and on the average of these four varieties, some 50 pods per plant were harvested. Seeds harvested in 1937 were planted in March, 1938., and within four days following the planting 85 per cent tuber, and many other characters were observed in the seedlings. The results indicate that breeding of sweet potato by seeds is decidedly practicable even in these districts where no natural flowering of the plant occurs, by the aid o shot-day treatment inducing the plants to bloom and set successfully.