濒危植物峨眉含笑种子发育的形态解剖研究  

Study on Morphology and Anatomy during Seed Development of the Endangered Plant Michelia wilsonii

作　　者：陈小红[1] 陈俐洁 龚志鸿 赵安玖[1] CHEN Xiaohong;CHEN Lijie;GONG Zhihong;ZHAO Anjiu(College of Forestry,Sichuan Agricultural University,Chengdu 611130,China;Leshan Academy of Forestry,Leshan 614000,Sichuan,China)

机构地区：[1]四川农业大学林学院,成都611130 [2]乐山市林业科学研究院,四川乐山614000

出　　处：《四川农业大学学报》2024年第5期1077-1084,共8页Journal of Sichuan Agricultural University

基　　金：四川省自然科学基金(22NSFSC0135)。

摘　　要：【目的】探究峨眉含笑种子发育过程中的形态解剖特征变化,解析其种子繁殖的生物学机制和濒危原因,为濒危植物的生态保育提供理论依据。【方法】以不同发育阶段的峨眉含笑种子为实验材料,采用石蜡切片法在显微镜下观测形态学变化和解剖结构特征,并用植物生理学方法对营养物质含量进行测定。【结果】种子发育初期为黄绿色圆球形,成熟后圆形子弹头状。外种皮红色革质,由3~4层表皮细胞构成;中种皮为橘红色肉质,由薄壁组织构成,细胞内后含物丰富,油脂感显著;内种皮中的扁平细胞分化成厚壁细胞,逐渐坚硬木质化,颜色由白色变为黑色。胚乳由薄壁细胞组成,胞内染成红色的后含物越来越多,形态从透明液态逐渐发育为坚实凝固态。种胚经历了球形胚、心形胚、鱼雷形胚和子叶形胚4个阶段,种子掉落时子叶形胚已发育完全。可溶性糖含量随种子发育呈先上升后下降的变化;淀粉和可溶性蛋白含量初期缓慢上升,中后期逐渐稳定;粗脂肪含量前期快速上升、后期积累放缓。【结论】种子发育过程中出现外种皮色彩鲜艳、中种皮油脂含量高、内种皮通透性差、种子早期停止生长、中后期胚乳发育异常和含胚率低等问题,导致峨眉含笑种子质量低下,限制了种子自然萌发和天然更新进程,是种群衰退甚至濒危的重要原因之一。【Objective】This study aims to explore the morphological and anatomical characteristics dur⁃ing seed development of Michelia wilsonii,analyze the biological mechanism of seed reproduction and the reasons for their endangerment,and provide theoretical basis for the ecological conservation of endan⁃gered plants.【Method】The seeds of M.wilsonii at different developmental stages were used as experi⁃mental materials,the morphological and anatomical characteristics were observed by paraffin section under microscope,and the nutrient content was measured by plant physiological methods.【Result】At the initial stage of development,the seeds exhibited a yellow-green hue and a spherosome shape,eventually matur⁃ing into a round-bullet shaped.The epidermis was characterized by a red,and leathery texture and con⁃sisted of 3-4 layers of epidermal cells.The mesotesta displayed an orange-red and fleshy appearance,composed of parenchyma tissue,contained abundant ergastic substance,with a pronounced oily texture.The flat cells within the endothelium differentiated into sclerenchymatous cells,which gradually became hard and woody,undergoing a color transition from white to black.The endosperm was composed of paren⁃chymal cells,containing a higher concentration of colored ergastic substance inside the cells.Its morphol⁃ogy gradually developed from transparent liquid state to solid solidified state.The development of the seed embryo proceeded through four stages:spherical,heart-shaped,torpedo shaped,and cotyledon shaped.By the time of the seed dispersed,the cotyledon-shaped embryo was fully developed.The soluble sugar content initially increased during seed development but subsequently decreased.The con⁃tents of starch and soluble protein exhibited a gradual increase during the initial stages of seed develop⁃ment,and gradually stabilized in the middle and later stages.The crude fat content increased rapidly in the early stage,followed by a deceleration in the later stages.【Conclusion】During the process of

关 键 词：种子发育 形态解剖 营养物质 峨眉含笑 

分 类 号：Q944.5[生物学—植物学]