钾营养对甘薯块根薄壁细胞微结构、^(14)C同化物分配和产量的影响

Effects of potassium on the parenchyma cell structure of storage root,the distribution of ^(14)C photosynthates and yield in sweet potato

选用徐薯 18号为材料 ,通过大田试验研究了供钾水平对甘薯块根薄壁细胞显微和超微结构、块根呼吸速率和ATP含量、14 C同化物分配和产量等的影响。结果表明 ,施用适量钾肥 ,甘薯块根薄壁细胞膜结构完整、清晰 ,内含较多的线粒体和质体 ,胞质较丰富 ;块根的呼吸速率和ATP含量较高 ,有利于提高块根“库”的活性。适量供钾 ,增加单位体积块根内的淀粉粒数 ,提高块根淀粉含量 ;促进光合产物由叶片向块根的运输 ,提高了14 C同化物在块根中的分配比例 ;促进块根迅速膨大 ,增加单薯重 ;

Field experiment with different potassium levels was carried to study the effect of potassium on the microstructure and ultrastructure of storage root parenchyma cells,the respiratory rate and ATP content of storage root,the distribution of 14C photosynthates and the storage root yield in sweet potato (Ipomoea batatas(L)Lam cv. Xushu18).The results showed that the application of adequate potassium was favorable to promote the sink activity,for in the storage root of sweet potato the parenchyma cells which were perfect in membrane and rich in cytoplasm contained much more mitochondrion and plastid;the respiratory rate and ATP content were all increased.Adequate K application increased starch grains in a unit volume and starch content of storage root,accelerated the transportation of 14C photosynthates from leaf to storage root and increased its proportion in storage root,promoted the storage root growth rate and increased its fresh weight.All of those contribute to increase storage root yield.