半湿润气候区土壤水分对冬小麦叶绿素值的影响

利用天水地区2007～2010年的冬小麦叶绿素含量(SPAD值)和土壤含水量实际观测资料,分析了土壤水分含量和SPAD值在冬小麦生育期内的动态变化过程,研究了冬小麦叶片SPAD值与不同深度土层土壤水分含量的关系,以及SPAD值与冬小麦生长量、产量构成要素和地段实产的关系。结果表明:(1)在冬小麦生育期内土壤含水量呈现减小趋势,叶片SPAD值则经历了一个先升高后降低的过程,浅层土壤含水量更易受降水的影响而升高;(2)土壤水分含量对冬小麦叶片SPAD值的影响主要集中开花期至乳熟期,土壤水分含量高的年份叶片SPAD值较高,反之则较低;(3)中浅层土壤水分含量与10d后冬小麦叶片SPAD值有显著的正相关性;(4)冬小麦叶片SPAD值与部分生长量和产量构成要素存在相关关系,但是与地段实际产量关系较弱。

Impact of soil moisture on the winter wheat SPAD readings in semi-humid climate zone

By using winter wheat SPAD readings and soil moisture actual observations in Tianshui from 2007 to 2010,the soil moisture contents and winter wheat SPAD readings variation during the growth period,the relationship between winter wheat SPAD readings and soil moisture content in different depth of soil,and relationship between SPAD readings and the amount of winter wheat,yield components and lots chattels were studied.The results shows that:(1) Soil moisture shows decreasing trend during the reproductive period,SPAD readings of leaves through a process firstly increase and then decrease,shallow soil moisture is more vulnerable to the effects of increased precipitation;(2) Impact of the SPAD readings of winter wheat leaves on soil moisture content mainly happens in flowering to milky stage,the leaf SPAD readings are higher in the year the soil moisture content higher,and vice versa;(3) Mid and shallow soil moisture content and winter wheat leaf SPAD readings 10d later have significant positive correlation;(4) Winter wheat leaf SPAD readings are correlated with some elements of the growth and yield,but weak relationship with the actual production lots.