Simulation model of dry matter accumulation in peanut under different irrigation quantity

Water test was got in 2007. Controling the soil moisture content in yield forming stage. According to the analysis of the classical growth theory, established a peanut growth model under control the soil water. The model was studies by using one peanut cultivar Fenghua 1. A peanut pool-culture experiment under control of rain protection shed was carried out to keep relative soil water content of 0-30cm layer in 90%, 70%, 50% in yield forming period. By measuring the dry matter accumulation and available water content in soil each treatments. Through regression analysis and curve fitting, dry matter accumulation dynamic accord with S-shaped curve, which can be expressed by logistic equation W=W_m/(1 + ae^-bt). Then make use of it to establish respective dry matter accumulation dynamic model for different water levels. The derivation of equation is dry matter accumulation rate GR and relative growth rate RGR= GR/W. Make available soil water content in the three different water levels as variables to set up the fitted equations RGR=f (Wi,dj)= A+B1*Wi*B2*Wi ̂², which expressed the relation between relative growth rate and relative soil water content. Geting the corresponding parameters A, B1, B2. A, B1, B2 curve fitting with growth process, so bring in the independent variable of growth period (dj). Then simulation model for dry matter accumulation relative growth rate is set up: RGR=f(Wi,dj) (Wi is soil water content at different growth stages, dj is growth period). Finally, the dry matter accumulation prediction model is established as W=f(Wi,dj,t)=W0*(1+RGR). In the present study,the model of peanut growth dynamic under different relative soil water content was obtained,which could descibe systematically yield forming dynamic of peanut, it lay a foundation for management decision using computer and developed precision production,so as to it can serve for high yield cultivation decision in peanut.But,the study only descibed the m- - odel in yield forming period, research emphasis will be the simulation model under control the soil water of the whole growth period in the future.