不同品种龙眼果实发育进程对其生理落果和熟性的影响

Influences of fruit development progress on the physiological abscission and maturity of different varieties of Longan

以早熟1号、石硖、储良、实生迟熟和立冬本5个不同熟性的龙眼(Dimocarps longana Lour)品种为材料,研究了果实发育进程对其生理落果和熟性的影响。结果表明:在分大小果期间的第2次生理落果高峰之后直至成熟,龙眼果实的落果率趋于稳定低水平,单穗果数缓慢下降,但品种间差异与熟性无关;在不同熟性龙眼果实的发育过程中,果实大小、单果质量、果形指数、果肉厚度、可食率和TSS含量的变化规律相似,但因熟性不同而表现为进程差异;与早熟品种相比,迟熟品种果实个体发育速率较慢,果形变化迟,子叶生长、种子发育完成、果实进入成熟期、完熟期和过熟期均需要较长的时间。与谢花期对果实熟性的影响相比,果实发育进程对决定品种熟性更有意义。

The influences of fruit development process on the physiological abscission and maturity of 5 different varieties of longan fruits （var. Zaoshu No.1, Shixia, Chuliang, Shisheng chishu and Lidongben） were all studied. The results demonstrated that, after the developing and aborted fruits discriminated, fruit abscission rates tended to be steady at a low level and the fruit amounts per cluster descended slowly from the second fruit abscission peak to maturation period, but were not relevant to the maturity of longan varieties. In the developing process of 5 varieties of longan fruits with different maturity, although the changes in the indices including fruit size, mass per fruit, fruit shape index, aril thickness, edible rate and TSS content showed a similar law, the differences in the fruit development progress varied with the different maturity of varieties. Compared with the late-maturity varieties, the single fruit of early-maturity varieties developed at a slower rate, turned in shape from ellipse into spherical more lately, and needed a long time to finish the periods of cotyledon and seed development, fruit maturing, ripening and over ripening. In a word, the maturity of different longan varieties could be determined by the fruit developing progress more than the anthesis.