320 REPRODUCTIVE DEVELOPMENT AND FRUIT QUALITY OF SWEET CHERRY

Abstract

Variability in maturity and quality of sweet cherry (Prunus avium L. `Bing') fruit at harvest is a major limitation to the crop's storage and marketing potential. Later blooming flowers resulted in poorer fruit quality Differences in bloom date were related to differences in flower primordial development during winter. Vigorous shoots grown in the previous season produced fewer flower buds per length of shoot than did shorter, less vigorous shoots, resulting in larger flower primordia on vigorous shoots, The effects on primordial and fruit development of altered leaf areas per flower bud the previous summer were examined. A decrease in leaf area per bud during summer reduced primordium size in mid-winter. Dormant flower primordia of 6-yr-old `Bing' trees on precocious `Giessen' rootstock, Gil48/1, were larger than those with `Mazzard' as rootstock. Flower primordia on dwarfing Gil48/8 rootstock were intermediate in size. Differences in primordial development and bloom date, whether due to management practices or rootstock, may affect fruit development and contribute to variability in fruit maturity and quality.