【目的】无患子(Sapindus mukorossi)是重要的生物日化和生物质能源树种,近年来我国无患子产业蓬勃发展,但目前在生产上仍没有明确的采收期或者确定最适采收时间的方法。通过对果实生长发育过程及内含物含量动态变化间的关系研究,确定无患子果实的最适采收时间。【方法】选取5株长势中等、开花结实良好的8年生实生无患子树,于果实膨大期的末期到果实脱落期,每隔4 d每株树采摘15个发育正常的果实,观察其外观变化,并进行果实、种子、果皮及种仁干质量,果实横径、纵径、侧径,种子横径、纵径、侧径共10项表型指标测定,以及种仁含油率、单种仁油质量、果皮含皂苷率、单果皮皂苷质量及含水率的测定。【结果】①9月底果实由绿色变为金黄色,随后在10月上半个月内失水,果皮表面皱缩,果实横径下降7.95%,侧径下降10.71%。②8月底至9月初种仁体积较小,呈绿色,随后逐渐长大,在9月20日左右由绿转黄,且在9月底完全变为黄色。种子横径、纵径和侧径在10月上旬明显下降, 其中横径下降10.81%,纵径下降4.87%,侧径下降8.96%。③果实和果皮的干质量变化趋势相同,均在10月15日之前上升,随后小幅波动,且果皮干质量发生第2次明显上升时种子干质量下降。④种仁油质量在9月中旬及之后较高,果皮皂苷质量在10月上旬和中旬较高。【结论】果皮中皂苷和种仁中油的积累在10月上旬均达到最高,针对果皮皂苷和种仁油的应用,最佳采果期在10月上旬和中旬。由果实外观判断,生产上,果实完全变为金黄且果皮开始皱缩后的20 d内,为最佳采果期。

【Objective】Soapberry (Sapindus mukorossi) is an important raw material species for biochemical, biomass energy industries. In recent years, China’s soapberry industry has seen booming growth. The fruiting period of soapberry is several months long and there is no clear harvesting period or method to determine the harvesting time during production. In this study, we conducted observations of fruit growth and development dynamics, as well as dynamic changes in the contents of inclusions, to clearly determine the harvesting time of soapberry fruits during production.【Method】Five eight-year-old living soapberry trees with medium growth and good flowering, and fruit set were selected. Three fruit sequences were randomly chosen from each tree every four days from the end of the fruit expansion period to the fruit abscission period. The ten phenotypic indicators, seed kernel oil content, mass of single kernel oil, pericarp saponin content, mass of single pericarp saponin and water content were determined.【Result】① The change in fruit color from green to golden yellow occurred at the end of September, followed by a water loss in the first half of October, along with wrinkling of the pericarp surface. A 7.95% decrease in the transverse diameter and a 10.71% decrease in the lateral diameter of the fruit were also observed. ② The seed kernels were small and green from the end of August to the beginning of September; these then grew gradually before changing from green to yellow around September 20 and completely changed to yellow at the end of September. The transverse diameter, longitudinal diameter and lateral diameter of the seeds decreased significantly in early October, with the transverse diameter decreasing by 10.81%, the longitudinal diameter by 4.87%, and the lateral diameter by 8.96%. ③ The dry mass of the fruit and pericarp showed the same trend, both rising until October 15 and then fluctuating slightly. We innovatively found that the dry mass of seeds decreased when the se-cond significant rise in pericarp dry mass occurred. The fruits finished drying in mid-October. ④ The content of single kernel oil was higher in mid-September and thereafter, whereas the content of single pericarp saponin was higher in early and mid-October.【Conclusion】 The accumulation of saponins in the peel and the oil of the seed kernels was the highest in early October, and the best fruit harvesting periods for peel saponin and the oil of single seed kernels were in early and mid-October. Judging from the fruit’s appearance, the optimum fruit harvesting period was within 20 days after the fruit completely turned golden yellow and the peel started to wrinkle in production.