澳洲坚果生理落果期果柄离区形态学结构及细胞壁相关酶活性分析  

Analysis of Morphological Structure and Cell Wall-Related Enzyme Activity in Carpopodium Abscission Zone of Macadamia during the Physiological Nut-Drop Period

作　　者：李穆[1] 李菊馨 曾黎明[1] 黄锦媛[1] 唐圣理 赵渊 LI Mu;LI Juxin;ZENG Liming;HUANG Jinyuan;TANG Shengli;ZHAO Yuan(Guangxi Subtropical Crops Research Institute,Nanning,Guangxi 530001,China)

机构地区：[1]广西壮族自治区亚热带作物研究所,广西南宁530001

出　　处：《农业研究与应用》2023年第5期21-25,共5页Agricultural Research and Application

基　　金：广西农业科学院基本科研业务费项目(桂农科2024YP131,2022YM11,2021YT155);广西农业科学院科技先锋队“强农富民“”六个一”专项行动项目(桂农科盟202304-07);广西科技基地和人才专项(桂科AD18281005)。

摘　　要：对比分析澳洲坚果早期生理落果期间正常果与脱落果果柄离区的形态学结构和细胞壁相关酶活性,为落果生理基础研究及生产上制定保果调控措施提供理论依据。通过制作石蜡切片观察果柄离区的形态学结构,采用生化微量法分别测定盛花后30 d、40 d、50 d果柄离区中纤维素酶、多聚半乳糖醛酸酶的活性并分析其差异性。结果表明,正常果果柄表皮细胞排列紧密,无离层区域,而脱落果果柄具有明显的离层区域,离层由2~3层大体积、椭圆形的细胞松散排列组成,细胞间隙较大,木质化程度高于周围组织细胞;在澳洲坚果早期生理落果期间,脱落果果柄离区中纤维素酶、多聚半乳糖醛酸酶活性均显著高于正常果果柄。研究结果表明,果柄离层木质化程度、纤维素酶、多聚半乳糖醛酸酶等细胞壁相关酶活性变化是造成澳洲坚果早期生理落果的重要因素。The morphological structure and cell wall-related enzyme activity in carpopodium ab‐scission zone of normal and dropped macadamia nuts in the early physiological nut-drop period were compared for theoretical basis on physiological research of nut and the formulation of nut preserva‐tion control measures in production.Paraffin section was used to observe the morphological structure of carpopodium abscission zone of macadamia.The activity of cellulase and polygalacturonase en‐zymes in carpopodium abscission zone of macadamia on 30 d,40 d and 50 d after flowering were tested by biochemical micromethod and their differences were analyzed.The results showed that the epidermal cells of the normal carpopodium were tightly arranged without the abscission zone,while the carpopodium of dropped nuts had obvious abscission zone.The abscission zone was composed of 2-3 large and elliptical cells that were loosely arranged,with larger cell gap and higher lignifica‐tion degree than the surrounding tissue cells.During the early physiological nut-drop period,the ac‐tivity of cellulase and polygalacturonase in carpopodium of dropped nuts were significantly higher than those in normal macadamia nuts.The results shows that the lignification degree of carpopodium abscission zone and the activity change of cell wall-related enzyme such as cellulase and polygalactu‐ronase are the important factors causing the early physiological nut drop of macadamia.

关 键 词：澳洲坚果 离区 果柄 纤维素酶 多聚半乳糖醛酸酶 

分 类 号：S664.9[农业科学—果树学]