Effect of Lateral Branch Wire-Girdling on Fruit Growth and Flower Bud Formation in 'Taishu' Japanese Persimmon

Lateral branches on 'Taishu' Japanese persimmon (Diospyros kaki Thunb.) were bound tightly with covered insulated wire (2 mm diam.) (wire-girdling) 2 weeks before full bloom to test its effects on fruit growth, fruit quality, leaf dry weight and female flower bud formation. The wire rings were removed at 60 days after treating. Fruit set percentage was increased by the treatments. After June to October, fruit growth was promoted by the treatment. Fruit size and weight, peel coloration and Brix value in fruit at harvest were promoted by the treatment. Dry matter percentage of leaf and specific leaf weight were increased from June to October by the treatment. From June to July, pistillate floral primordium was differentiated early in shoots on branches treated wire-girdling. In the next spring season, the number of female flowers on shoots sprouted in wired branches increased. It was suggested that promoted fruit growth, high Brix value in fruit and high female flower bud formation by wire-girdling lateral branches were caused by high dry weight accumulation in leaves.