カキの果実品質に及ぼす開花日, 種子, GA処理ならびに結果部位の影響

Abstract

The effects of bloom date, seediness and location of the fruit in the foliar canopy on the fruit quality of persimmon cv. Maekawa-Jiro and the relation between GA treatment and fruit quality of persimmon cv. Jiro were studied.1. Flowers which bloomed 12d later (delayed flowers) than those of the main flower population (normal flowers), gave rise to small, poorly colored fruits having low soluble solids content.2. Fruits borne high and on the outer periphery of the foliar canopy developed better color and had high soluble solids content as compared to those borne low and in the interior part of the canopy. The width of epidermal cracks at the apex of fruits derived from delayed flowers were as wide as cracks on fruits which developed from normal flowers. Seeded fruits, especially those borne on the periphery of the canopy and exposed to high light intensities, possessed wide apical cracks. Conversely, on trees which produced predominantly seedless fruits, the apical cracks were narrow, independent of their location in the canopy.3. On trees which produced many seeded fruits, the seedless ones were small, slow in developing color, and possessed low soluble solids content as compared to seeded fruits, whereas, on trees bearing fruits with a few seeds, seedless and seeded fruits were similar in size, color and soluble solids content.4. Hand pollination of normal and delayed ‘Jiro’ flowers increased the percentage fruit set. Gibberellic acid (GA3) applications to pollinated and nonpollinated flowers improved fruit set but decreased seed count/fruit compared to untreated fruits. GA-treated fruits were smaller and the widths of apex crackings were narrower than those of untreated ones.