五个典型柑桔品种的落花落果规律调查

以成年纽荷尔脐橙、兴津温州蜜柑、沙田柚、尤力克柠檬和圆金柑为材料，探索其花果脱落规律。结果表明，最终坐果率与总花量（含花蕾）显著负相关（P < 0.01）；平均单株花果脱落总数量为兴津温州蜜柑 > 纽荷尔脐橙 > 沙田柚 > 圆金柑 > 尤力克柠檬；平均单株花果脱落总干重为兴津温州蜜柑 > 纽荷尔脐橙 > 沙田柚 > 尤力克柠檬 > 圆金柑；纽荷尔脐橙、兴津温州蜜柑和沙田柚第一次生理落果数量大于第二次生理落果，尤力克柠檬和圆金柑第二次生理落果数量大于第一次生理落果。因此，纽荷尔脐橙、兴津温州蜜柑和沙田柚应重点防止第一次生理落果，尤力克柠檬和圆金柑应重点防止第二次生理落果。

Characteristics of flower and young fruit drop of five typical citrus varieties

Characteristics of flower and young fruit drop of 5 typical China citrus varieties, Newhall navel orange (Citrus sinensis L. Osb.cv.''Newhall''), Okitsu Wase satsuma (Citrus unshiu Marc.cv.Okitsu wase), Shatian pomelo (Citrus grandis Osb.cv. ''Shatian''), Eureka lemon (Citrus limon Burm.f.) and Round kumquat (Fortunella japonica Swingle) , were investigated in 2012. Results showed that the final fruit set ratios were significantly negative correlated with the total numbers of flower buds (P < 0.01). The total numbers of dropped flower buds, dropped flowers and dropped fruits were Okitsu Wase satsuma > Newhall navel orange > Shatian pomelo > Round kumquat > Eureka lemon, while the total dry weights of those dropped oragens were Newhall navel orange > Okitsu Wase satsuma > Shatian pomelo > Eureka lemon > Round kumquat. For Newhall navel orange, Okitsu Wase satsuma and Shatian pomelo, the numbers of fruits dropped during the first physiological drop (FPD) were greater than the second physiological drop (SPD), while it was contrary for Eureka lemon and Round kumquat. Therefore, for Newhall navel orange and Okitsu Wase satsuma, it is necessary to control excessive flowering. Furthermore, it is important to reduce FPD for Newhall navel orange, Okitsu Wase satsuma and Shatian pomelo, while to prevent SPD is important for Eureka lemon and Round kumquat.