基于有效积温的玉米叶片和叶鞘干物质动态积累模型及特征参数分析OA

[Objective]To explore the dynamic accumulation model of leaves and leaf sheaths dry matter in maize varie-ties based on effective accumulated temperature and analyze its characteristic parameters,which could provide theoretical basis for breeding maize varieties that efficiently utilized light and heat resources and tap into the yield potential of varie-ties.[Method]A field experiment was conducted with spring and summer sowing maize varieties Zhuyu 216,Yufeng 303,Zhongkeyu 505,and Zhengdan 958 in 2023 as experimental materials,the Logistic equation was used to construct the dynamic accumulation model of dry matter in leaves and leaf sheaths of different maize varieties based on effective ac-cumulated temperature,the model was tested by field measured values,and its characteristic parameters were analyzed.[Result]There was an extremely significant positive correlation between leaf and leaf sheath dry matter in spring and sum-mer sowing maize varieties with effective accumulated temperature(P<0.01),the dry matter mass of leaves and leaf sheaths went through three periods:gradual increase period,rapid increase period,and slow increase period,it showed an S-shaped trend with effective accumulated temperature,and the accumulation pattern of dry matter in leaves and leaf sheaths was basically the same among different maize varieties.The Logistic model of leaves and leaf sheaths dry matter growth of maize varieties based on effective accumulated temperature had the good practical biological significance,the determination coefficients R2 were 0.9799-0.9922 and 0.9781-0.9963 respectively,and the standardized root mean square errors nRMSE were 10.38％-23.71％and 12.71％-28.80％respectively.The measured values were evenly distributed on both sides of the simulation curve,and were very close to the simulation curve,reaching a good prediction level.The ef-fective accumulated temperatures required for the rapid increase of leaves and leaf sheaths dry matter in spring and sum-mer sowing maize varieties were 479.21-576.75℃·d and 550.39-665.42℃·d respectively,the effective accumulated temperatures required to reach the maximum growth rate were 579.74-731.68℃·d and 647.94-810.14℃·d respectively.The average growth rates in rapid growth period were 0.0680-0.1276 g/℃·d and 0.0404-0.0706 g/℃·d respectively.[Conclusion]The Logistic model based on effective accumulated temperature has good prediction and interpretation for the accumulation dynamics of maize leaves and leaf sheaths dry matter,and can be used for dynamic estimation of dry matter accumulation in leaves and leaf sheaths of different maize varieties,with strong application value.