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[目的]解决丘陵地区甘薯栽插密度过稀(37 500~40 500株/hm2)的问题。[方法]以淀粉型甘薯品种济薯21和鲜食型甘薯品种济薯22号为试验材料,研究了栽插密度对甘薯产量及源库特性的影响。[结果]济薯21和济薯22号叶面积系数随密度的增加而增大,同一密度在全生育期呈单峰曲线,40~80 d为快速上升期,80 d左右为最高峰,随后开始缓慢下降;随密度的增加,群体通风透光性下降,两个品种的单株叶数、分枝数、蔓长、茎叶干鲜重呈下降趋势,当密度超过75 000株/hm2时,产量显著降低。品种间最适栽植密度存在差异,济薯21最适栽植密度为45 000~60 000株/hm2,济薯22号最适栽植密度为60 000~75 000株/hm2。[结论]适宜的密度可产生合理的群体结构,较好协调甘薯地上部生长和地下部生长的关系,可以获得高产。品种间最适栽插密度存在差异,在确定品种栽插密度时,应综合考虑基因型、环境、地力、栽插期等因素。
[Objective] The research aimed to solve the problem of sweet potato transplanting density (37 500 ~ 40 500 plants / hm 2) in hilly areas. [Method] The effects of planting density on sweet potato yield and source sink characteristics were studied with two sweet potato varieties, namely, Yishu 21 and sweet potato variety Xiashu 22. [Result] The leaf area coefficient of Jinshu 21 and Jishu 22 increased with the increase of density. The same density showed a single peak curve during the whole growth period, 40 ~ 80 d was the rapid rising period, and the peak was about 80 d, then Began to decline slowly. With the increase of density, population ventilation and transpiration decreased. The number of leaves per plant, number of branches, length of stems, dry weight of stems and leaves decreased in both varieties. When the density exceeded 75 000 plants / hm2 , Yield is significantly reduced. The optimum planting densities among cultivars were different. The optimal planting densities of Jishu 21 was 45 000 ~ 60 000 plants / hm2, while that of Jishu 22 was 60 000 ~ 75 000 plants / hm2. [Conclusion] The appropriate density could produce a reasonable population structure, which could well coordinate the relationship between shoot growth and underground growth of sweet potato and obtain high yield. The optimal transplanting density is different among breeds. When determining transplanting density, the factors such as genotype, environment, fertility and planting period should all be considered.