不同覆盖物对甘薯光合特性和产量的影响

Impact of Different Film Mulching on the Photosynthetic Characteristics and the Yield of Sweet Potato Varieties

【目的】筛选甘薯栽培的最佳覆盖方式,为甘薯高产栽培提供理论依据。【方法】以‘榕薯819’为材料,栽培过程中采用稻草加土、黑色地膜和透明地膜进行覆盖,测定了甘薯产量及叶片相关的光合特性指标,并对其进行相关性分析。【结果】(1)覆盖黑膜的处理产量最高,透明膜其次,草+土最低,这3个处理均显著高于对照,分别比对照增产29.17%、20.83%和11.11%;(2)3个处理的甘薯产量与净光合速率、胞间CO_2浓度、叶绿素含量均呈极显著正相关,与蒸腾速率呈显著正相关;(3)3个处理的净光合速率与胞间CO_2浓度、蒸腾速率和叶绿素含量均呈极显著正相关,与水分利用率呈显著正相关,与气孔阻抗呈极显著负相关。【结论】生产上宜选用黑膜作为覆盖物,可以增强光合速率,进而提高甘薯产量。

[ Purposes ] The experiment was to choose the best mulching method and provide a theoret-ical basis of high-yield cultivation of sweet potato. [ Methods] We tested the yield and the photosyn- thetic characteristics related indicators of leaves and carried out the relevance analysis, using the straw and soil, black plastic film, and transparent plastic film as the mulching during cultivation of ＇ Rong- shu-819＇. [Results] （1） The yield of the treatment with the black plastic film mulching was the highest, the transparent plastic film treatment lower, and the straw and soil treatment was the lowest. （2） The yield of three treatments all had extremely significant positive correlations with net photosyn- thesis rate （Pn）, intercellular CO2 concentration （ Ci ） and the contents of chlorophyll, significant positive correlations with transpiration rate （Tr）. （3） In three treatments, P, all had extremely signif- icant positive correlations with Ci, Tr and the contents of chlorophyll, positive correlations with water use efficiency （WUE）, and significant negative correlations with stomatal resistance （St）. [ Con- clusion ] In this experiment, we concluded that the black plastic film could be used as the mulching in production, which could increase P, and the yield of sweet potatoes.