人工授粉对永嘉早香柚果实发育与贮藏品质的影响

Effect of artificial pollination on fruit development and quality in storage of Yongjiazaoxiangyou pomelo

永嘉早香柚是浙江温州地方名柚,具单性结实能力,可在无授粉品种混植时结无籽果,也可经人工授粉处理形成有籽果。研究表明,未授粉果实具有无籽优势,但糖酸指标则逊于授粉果。正常采收期(花后165d)未授粉果实果肉可溶性糖含量比授粉果低4.72mg/gFW,而果汁pH低0.07。75d贮藏期间果肉可溶性糖含量无明显变化,而果汁pH趋于上升,授粉果果汁pH上升0.29而未授粉果仅上升0.19。授粉果实在45d贮藏期间未发生明显枯水,而且不溶性膳食纤维含量下降38.10%,而未授粉果实贮藏期间易发生枯水,贮藏45d后枯水指数达0.5,不溶性膳食纤维含量上升至2.33mg/gFW,为同期授粉果实的2.56倍。未授粉果实枯水发生前期汁囊组织出汁率无明显下降而严重枯水(贮藏45d)时下降至64.08%(贮藏前为75.70%)。人工授粉显著改善了永嘉早香柚果实品质。

Yongjiazaoxiangyou pumelo (Citrus grandis Osbeck) is a famous local pomelo cultivar grown in Wenzhou, Zhejiang Province. Parthenocarpically seedless fruit can be produced without pollination, but the big difference in fruit quality and storage performance were found between seedless (unpollinated) and seeded (hand pollinated) fruit. Unpollinated fruit harvested at 165 d after full blossom had a lower content (by 4.72 mg/gFW) of soluble sugars and a lower juice pH (by 0.07) than those of hand pollinated ones. No significant changes in soluble sugar contents, and an increase in juice pH by 0.29 and 0.19, respectively for hand pollinated and unpollinated fruit, were observed during 75-day storage. Unpollinated fruit were highly susceptible to juice sac granulation, with a grannulation index as high as 0.5 at 45 d in storage, while no obvious granulation occurred for pollinated ones. The content of insoluble dietary fibers for unpollinated fruit after stored for 45 days increased to 2.33 mg/g FW, 1.56 times higher than that of hand pollinated ones (the content for hand pollinated ones decreased only by 38.10%). The juice percentage of umpollinated fruit declined significantly (from 75.70% to 64.08%) when stored for 45-day. In conclusion, the hand pollination significantly improved the fruit quality of Yongjiazaoxiangyou pumelo.