不同施肥和栽培密度对双高大豆品种牡丰7号光合特性的影响

Effects of Fertilization Level and Planting Density on the Photosynthetic Characteristics of Double-High Soybean Variety Mufeng No.7

采用裂区设计,以双高大豆牡丰7号为材料,以施肥水平（300、345、390、435和480 kg.hm-2）为主区,栽培密度（30×104、32×104、34×104、36×104和38×104株.hm-2）为副区,研究了施肥水平和栽培密度对大豆光合特性的影响。结果表明：牡丰7号叶片叶绿素a、叶绿素b和总叶绿素含量受施肥量和栽培密度的影响不大,其含量主要是由该品种特性决定的;在一定范围内,牡丰7号群体叶面积指数随着施肥量和栽培密度的增加而增加,分别在施肥量为435 kg.hm-2和密度为36×104株.hm-2时达到最大值;开花期光合速率随着栽培密度的增加逐步降低,在栽培密度超过32×104株.hm-2后结荚期光合速率随着栽培密度的增加逐步增大,而结荚期光合速率随着施肥量的增加呈现出逐渐下降的趋势;随着施肥量的增加,开花期叶片蒸腾速率表现出先增后降的趋势,结荚期表现出逐渐下降的趋势;栽培密度在30×104~36×104株.hm-2时,牡丰7号结荚期叶片蒸腾速率随着栽培密度的增加逐步降低。

Taking double-high soybean variety Mufeng No. 7 as material, the effects of fertilization level and planting density on photosynthetic characteristics were investigated in a split-plot experiment with 5 fertilizer levels（ 300,345,390,435,480 kg-hm2）and 5 planting densities（ 30×104、32×104、34×104、36×104 38×104 plants.hm2 ）. The results showed that： the fertilization levels and planting densities had little impacts on the chlorophyll a,chlorophyll b and total chlorophyll contents for the leaves of Mufeng No. 7,and their contents were mainly determined by the characteristics of the species. Within a certain range, the leaf area index of Mufeng No. 7 increased as the fertilizer application and planting density increased with the peak value for the 435 kg.hm 2 of fertilizer application and 36 ）〈 104 plants.hm 2 of planting density,respectively. During the flow ering period,the photosynthetic rate decreased with the gradual increase of plant density. After the planting density was more than 32 × 104 plants·hm^- 2 the photosynthetic rate increased gradually as the planting densities increased while the photosynthetic rate declined as the fertilizer application increased during the podding period. With the increase of fertilizer application, the transpiration rate first increased and then decreased during the flowering period, while decreased gradually during podding period. In the range of 30 × 104 - 36 ×104 plants· hm ^2 for the planting density,the transpiration rate for leaves of Mufeng No. 7 was reduced gradually as the planting density increased during the podding period.