Research on Growth Model for Hydroponic Lettuce in Facility Plastic Greenhouse in Southern China
In order to optimize the digital production management measures of hydroponic lettuce in facility plastic greenhouse in southern China,the hydroponic planting experiments on'Italian lettuce'were conducted in facility plastic greenhouse of Guangdong Agro-meteorological Experimental Station from November 2021 to February 2022.Models for predicting hydroponic lettuce growth index based on two agro-meteorological indicators of effective accumulated temperature(EAT)and product of thermal effectiveness and PAR(TEP)were used to determine greenhouse environmental elements and lettuce growth data,and the models were validated by independent experimental sampling data.The results showed that,(1)the determination coefficients(R2)of the predicted and measured values of leaf number,leaf area,leaf fresh and dry weight based on the EAT model were as follows:0.911,0.963,0.948 and 0.934,the root mean square errors were 3.194 pieces,398.298 cm2,26.488 g and 1.934 g.(2)The R2 of the predicted and measured values of the model based on the TEP indicator were 0.940,0.972,0.965 and 0.956,the root mean square errors were 1.260 pieces,170.672 cm2,9.261 g and 0.464 g,respectively.This study suggests that the TEP model is superior to EAT model in general,and the fitting accuracy of TEP model between the predicted value and the measured value is better than EAT model in facility plastic greenhouse of southern China.