关键词: 芝麻, 盛花期, 渍水, 株高, 叶龄, 定量分析, 模型构建

Abstract: In order to evaluate the effect of different waterlogging duration at full flowering stage on plant height and leaf age of sesame,two plot experiments were conducted.Two sesame cultivars with different tolerance to waterlogging,Zhongzhi 13(tolerant type) and Zhengzhi 13(susceptible type),were assigned as main plots and five waterlogging duration of 0 h,24 h,36 h,48 h and 60 h at full flowering stage(represented by CK,W24h,W36h,W48h and W60h,respectively) were chosen as subplots.The growth curve,as well as normalization method,were used to quantitatively analyze plant height and leaf age,taking the relative days after emergence as an independent variable and the relative plant height as a dependent variable.The results showed that waterlogging increased plant height,and decreased leaf age of sesa me.The growth dynamics of plant height and leaf age,accorded with the “S” curve,were well simulated by the Logistic equation,with the root mean squared error(RMSE) of 14.68 cm and that of 2.49 pairs.The coefficient of multiple determinations(R²) was 0.970 for plant height and 0.975 for leaf age. Waterlogging had a significant effect on k for plant height and k’ for leaf age.The mean k of all waterlogging treatments increased by 9.34% for Zhongzhi 13 and 10.16% for Zhengzhi 13,respectively.In contrast, the mean k′ in all waterlogging treatments decreased by 10.69% for Zhongzhi 13 and 10.16% for Zhengzhi 13,respectively. Tmax for plant height in both Zhongzhi 13 and Zhengzhi 13 was less than 0.554.In case of leaf age,T_max of four treatments in Zhongzhi 13 changed between 0.554 and 0.590,while T_max of W24h and W36h in Zhengzhi 13 varied between 0.554 and 0.590,and T_max of W48h and W60h in Zhengzhi 13 was lower than 0.554.The mean of T1 ,T2 ,T3 ,t2 of plant height for all waterlogging treatments in Zhongzhi 13 were higher than those in Zhengzhi 13.However,the mean of V2 and V3 of plant height for all waterlogging treatments in Zhongzhi 13 were smaller than those in Zhengzhi 13.The mean of T2 ,T3 ,t2 of leaf age for all waterlogging treatments in Zhongzhi 13 were higher than those in Zhengzhi 13.However,the mean of T1 ,V2 ,V3 ,V2 and V3 of plant height for all waterlogging treatments in Zhongzhi 13 were smaller than those in Zhengzhi 13.The relative growth duration and relative growth rate of plant height,as well as the relative growth rate of leaf age during rapid-increase and slow-increase stage,are the main factors leading to the difference of plant height and leaf age response to waterlogging.

Key words: Sesame, Full flowering stage, Waterlogging, Plant height, Leaf age, Quantitative analysis, Model building