不同土层土壤容重组合对花生光合特性和干物质积累的影响

摘要

为探究土壤容重影响花生生长的作用机制并为花生高产耕作栽培体系的建立提供理论依据,本试验以高产花生品种青花7号为材料,设置0～20 cm土层土壤容重分别为1.2、1.3 g/cm32个水平,21 ～40 cm土层土壤容重分别为1.3、1.4、1.5 g/cm33个水平,共组合为6个处理(T23、T24、T25、T33、T34、T35),采用土柱栽培法,研究了不同土层土壤容重组合处理对花生不同生育期光合特性和干物质积累的影响.结果表明,在21 ～40 cm土层土壤容重相同条件下,0～20 cm土层土壤容重1.2 g/cm3处理的单株叶面积、光合速率、根茎叶干物质积累在苗期、荚果干物质积累在花针期均较1 .3 g/cm3处理高,其他生育期则均较1 .3 g/cm3处理低;在0～20 cm土层土壤容重相同条件下,花生单株叶面积、光合速率、根茎叶荚果干物质积累均随着21 ～40 cm土层土壤容重的增大而降低.0～20 cm土层土壤容重为1 .2 g/cm3时有利于花生苗期光合特性提高和干物质积累,但不利于花生中后期光合特性提高和干物质积累,21 ～40 cm土层土壤容重过高则在整个生育期间均不利于光合特性提高和干物质积累.适宜的土壤容重组合T23、T33 既利于花生苗期光合特性提高和干物质积累,又利于中后期光合特性提高和干物质积累.%In order to explore the mechanism of soil bulk density on peanut growth and provide theoreti-cal bases for the establishment of high-yield cultivation system of peanut,the high-yield peanut cultivar Qin-ghua 7 was used as the material in this study.The soil bulk densities were set as 1.2 g/cm3and 1.3 g/cm3in 0～20-cm soil layer,and 1 .3,1 .4 g/cm3and 1 .5 g/cm3in 21 ～40-cm soil layer,which formed 6 treat-ments (T23,T24,T25,T33,T34,T35)in total.The effects of soil bulk density on the photosynthetic charac-teristics and dry matter accumulation of peanut were studied using soil column method.The results showed that,under the same bulk density in 21 ～40-cm soil layer,the leaf area,photosynthetic rate,dry matter ac-cumulation in root,stem and leaf in seedling period and dry matter of pod in pod-pin stage under 1 .2 g/cm3 were higher than those under 1 .3 g/cm3in 0～20-cm soil layer,but lower than 1 .3 g/cm3in other periods. Under the same soil bulk density in 0～20-cm soil layer,the leaf area,photosynthetic rate,dry matter accu-mulation in root,stem,leaf and pod decreased with the increase of soil bulk density in 21 ～40-cm soil lay-er.It indicated that,the soil bulk density of 1 .2 g/cm3in 0～20-cm soil layer was beneficial to improve the photosynthetic characteristics and dry matter accumulation of peanut seedlings,but was not conducive to the improvement of photosynthetic characteristics and dry matter accumulation in the middle and late growth stage. Higher soil bulk density in 21 ～40 -cm soil layer was not conducive to the improvement of photosynthetic characteristics and dry matter accumulation in whole growth period.The suitable bulk density combination T23 and T33 were conducive to the improvement of photosynthetic characteristics and dry matter accumulation in seedling,middle and later periods.