植物体内光合同化物韧皮部装载和卸出研究进展  

Progress in phloem Ioading and unloading of plant photoassimiate

作　　者：龚月桦[1] 高俊凤[1] 李锦辉 

机构地区：[1]西北农业大学基础科学系,陕西杨陵712100

出　　处：《西北植物学报》1999年第4期738-745,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金!39670436

摘　　要：近年来研究表明，植物体内光合同化物的韧皮部装载和卸出均有共质体途径和质外体途径，装载转运的糖类主要有：（1）棉子糖及其类似物（以共质体方式装载）；（2）蔗糖（以质外体方式装载）。同化物的共质体卸出可通过扩散和集流两种作用实现，而质外体卸出则根据蔗糖在质外体是否水解而分为两种类型。卸出和装载的途径、机理因植物种类及库源关系而不同，也会受生长发育阶段及环境的变化而调整。深入研究韧皮部装载和卸出调控机制，对高产农业的理论发展和生产实践都有重要意义。The research of recent years shows that phloem loading and unloading of plant photoassimi1ate both have symplasmic and apoplasmic pathways. Sugars transported by loading main1y are: (1) raf finose and its analogue (in symplasmic pathway), (2) sucrose (in apoplasmic). Symplasmic unloadlng of photoassimilate occurs through bulk flow and diffusion,but apoplasmic unloading is clarified into two types according whether sucrose is hydrolysable or not. The mechanisms of loading and unloading are different with plant species and the sink－source relationship of the whole plant. They also adapted with growth stages and the change of enviroment. It has important significance for theory development and practice of high－yie1d agriculture to study in advance the control mechanism of phloem loading and unloading.

关 键 词：光合同化物 韧皮部 装载 卸出 

分 类 号：Q945.18[生物学—植物学]