基于Logistic模型水稻地上部干物质与叶面积指数模拟与分析

Simulation and analysis of above-ground dry matter and leaf area index of rice based on Logistic model

为研究“单本密植-大苗机插”技术下水稻地上部干物质积累量以及叶面积指数增长特性,以晶两优华占为材料,在3种大田种植密度(常规密度D0:16万穴·hm;、中密度D1:19万穴·hm^(-2)、高密度D2:24万穴·hm^(-2))和2种施肥(常规施肥处理N0、减施肥处理N1:常规施肥基础上减肥24.19%)下比较其产量形成差异,运用Logistic方程对群体叶面积指数和地上部生物学产量增长动态及其特征参数进行模拟,适当增加种植密度减少施肥量可增加产量。结果表明,D2N1处理产量较D0N0处理高2.53%,其主要通过增加单位面积穗数增加产量。通过Logistic模型拟合参数发现,不同种植密度及施肥量群体叶面积指数拐点集中于38.63~43.79 d,R;值为0.909~0.998;地上部干物质量拐点集中于63.80~82.14 d,R2值为0.960~0.996,通过实际观测值与拟合曲线估计值比较发现,群体叶面积指数实际观测值与拟合曲线估计值决定系数大于0.90,地上部干物质量实际观测值与拟合曲线估计值决定系数大于0.95,均较好模拟群体叶面积指数、地上部干物质量增长特性。采用“单本密植-大苗机插”技术,在常规施肥基础上减施肥料24.19%,增加33.30%移栽密度,可增产2.53%;不同种植密度及施肥量群体叶面积指数以及地上部干物质量增长特性符合Logistic模型,利用该模型可有效评价不同种植密度及施肥量水稻群体生长发育,为建立水稻高产群体提供参考。

In order to study the dry matter accumulation and leaf area index growth characteristics of rice above-ground under the technology of"single density planting and large seedling mechanical transplanting",taking Jing Liang You Hua Zhan as the material,the differences of yield formation were compared under three field planting densities(conventional density D0:160000 hole·hm;,medium density D1:190000 hole·hm^(-2),and high density D2:240000 hole·hm^(-2))and two fertilization treatments(conventional fertilization treatment N0,and reduction fertilization treatment N1:conventional fertilization on the basis of 24.19%).Logistic equation was used to simulate the growth dynamics and characteristic parameters of population LAI and above-ground biomass.On the basis of conventional fertilization amount and conventional planting density,increasing planting density appropriately to reduce fertilization amount could increase economic yield.Under the experimental conditions,the yield of D2N1 treatment was 2.53%higher than that of D0N0 treatment,which mainly increased economic yield by increasing the number of panicles per unit area.Through the Logistic model fitting parameters,it was found that the inflection point of leaf area index of different planting densities and fertilizer rates was concentrated in 38.63-43.79 d,and the R;value was 0.909-0.998.The inflection point of above-ground dry matter mass was concentrated in 63.80-82.14 d,and the R;value was 0.960-0.996.Through the comparison between the actual observation value and the estimated value of the fitting curve,it was found that the determination coefficient of the actual observation value and the estimated value of the fitting curve of the population leaf area index was greater than 0.90,and the determination coefficient of the actual observation value and the estimated value of the fitting curve of the above-ground dry matter mass was greater than 0.95,which could simulate the growth characteristics of the population leaf area index and the above-ground dry matter mass.Using the technology of"single close planting-seedling mechanical transplanting",on the basis of conventional fertilization,the fertilization was reduced by 24.19%,and the transplanting density was increased by 33.30%,which could increase the yield by2.53%.The growth characteristics of leaf area index and above-ground dry matter mass of rice population with different planting densities and fertilization amounts were in line with Logistic model,the model could effectively evaluate the growth and development of rice population with different planting densities and fertilization amounts,and provide references for the establishment of high yield rice population.