甘薯产量形成动态及蛋白质的分配与积累

THE DEVELOPMENT OF YIELD AND THE DISTRIBUTION AND ACCUMULATION OF PROTEIN IN SWEET POTATOES

根据甘薯产量性状形成动态,将全生长过程分为3个时期:前期为植后60d内,中期为60～90d,后期为90～150d。干、鲜蔓重,中期达最大值,以后下降;干、鲜薯重,前期增长慢,中、后期增长快;生物总产量,受薯重影响大,后期增长较快;薯块烘干率、淀粉率,均以中期增长快,并现峰值;薯块可溶性糖的含量和产量,主要在后期递增。 全生长期内,甘薯各器官蛋白质含量的高低顺序:叶片>吸收根>叶柄>地上茎>块根。各器官蛋白质含量,均以植后30d起呈递减。蛋白质分配主流,随生长期进展,从地上部逐渐转向地下部(块根)。蛋白质积累产量,前期直线上升,中期相对稳定,后期缓升,块根蛋白质积累产量与块根干物率和干、鲜薯重,呈极显著正相关。

In accordance with the development of yield,the growth process of the sweet potato plant could be divded into three phases; 60, 60-90 and 90-150 days after planting were defined as early,middle and late growth stages respectively.The fresh and dry weights of vines reached the maximum amount in the early stage and decreased from then on. The fresh and dry weights of tubers increased slowly during the early stage and speeded up in the middle and late atages. Total biological yield,which was greatly affected by tuber weight,increased relatively faster in the late growth stage. The ratio of fresh weight to dry weight and the percentage of starch in tuber increased relatively faster and reached peak value in the middle growth stage. The accumulated yield and the content of soluble sugar in tubers increased mainly in the late stage.For the whole growth season the protein contents in organs of the sweet potato plant were ranked as follows:leaf blade>root>leaf- stalk>stem>tuber. The protein contents of the various organs began to decrease 30 days after planting, with the development of plant growth the main flow of protein movement shifted from the aerial parts to underground parts (tubers). The accumulated yield of protein had a linear increase in the early growth stage, remained relatively stable in the middle stage and increased slowly again in the late stage. There was a very significant positive correlation between the accumulated protein amount of tubers and the dry matter ratio, as well as between it and the dry weight and fresh weight of tuber.