Studies On Temperature-Driven Morphogenesis Simulation Of Greenhouse Melon Aerial Part

Virtual Reality (VR) model of plant can be achieved by following steps. Firstly, practical measurement of plant growing data. Secondly, building of plant growing simulation models(based on agricultural informations and mathematical modeling methods). Thirdly, management of different model base(model base managing platform). Forthly, the building of plant visualization model. Finally, Virtual Reality (VR) model of plant can be synthetized by computer technologies. The calculation of plant growth process is the first vital step to realize the VR model. Melon growth and development was effected by too many factors, such as temperature, humidity, light, carbondioxide, cultivars , nutrition, etc. The calculation of Accumulated Thermal Units(∑TU) can overcome the disadvantage of conventional methods, such as GDD which can not clearly describe the temperature effect to melon growth when the temperature excesses the optimum point. Otherwise, the heat needed in the whole life of different genotypes melon is nearly certain. In this study, taking∑TU as the model driving force mainly based on melon biological regularity and in the consideration of model stability. The differences of the different genotypes melon geometric indexes treated with four different rates of organic fertilizer during the process of growth and development were comprehensively analyzed, thus built morphology dynamic simulation models of melon organs aboved the ground with the mathematical modeling tools and has a good performance on the explanation and prediction of different genotypes melon growth and development characters. Thus all that referred aboved laid an important and basical technical support for the construction of greenhouse melon VR model.Building mathematical models based on dynamic growth process of greenhouse melon leaf length,leaf width leaf and leaf area growth were important parts to achieve the VR model of greenhouse melon. In this study, the leaf length, leaf width and leaf area growth and development characters of three different genotypes melon, Cucumis melo L. (Dongfang-mi NO.1), Cucumis melo var.reticulatus Naud.(Wanglu), Cucumis melo var. cantalupensis. (Jinlu) treated with four different levels of organic fertilizer rates on different leaf positions were observed at fixed point from time to time and comprehensively analyzed the differences of the melon leaf geometric indexes during the process of growth and development, thus built dynamic simulation models of melon leaf length,leaf width and leaf area growth. The result showed the dynamic elongation of leaf length,leaf width growth with the dynamic changes of∑TU accord with an objective law of logistic mathematical models, both of leaf morphology indexes and growing rates of these treated melon have significant differences. Logarithmic equation and quadratic curve equation were used to describe the dynamic changes of leaf length and leaf width growing to fixed point with changes on different leaf positions, the leaf area dynamic changes with the elongation of leaf length and width were simulated by binary regression equation. In addition, leaf nitrogen contents models were used to describe the quantitative impact on the leaf morphogenesis under different levels of organic fertilizer. The model was validated with independent field experiment datas and the results showed and the results showed that the mean RMSEs of leaf length,leaf width and leaf area under different∑TU were 0.54 cm,1.19cm,0.4435cm2. These leaf length,leaf width,leaf area mathematical model have a good performance in prediction and thus laid a technical support for the greenhouse melon VR leaves models.Simulation of melon internode and leaf angle was important part to realize the melon growth morphology model and also was the key point to achieve the melon Virtual Reality (VR) model. The characters of melon internode length, leaf angle treated with four different levels of organic fertilizer rates on different leaf positions were observed at fixed point from time to time and comprehensively analyzed the differences of the melon leaf geometric indexes during the process of growth and development, thus built dynamic simulation models of melon internode and leaf angle growth.The result showed that the difference of three different genotype melon treated with four different rates of organic fertilizer was significant,logistic mathematical models were used to simulate the dynamic elongation of internode length with the dynamic changes of∑TU, dynamic changing characters of leaf angle on different leaf positions were respectively described with piecewise functions of logarithmic equation,quadratic curve equation,linear equation with the dynamic changes of∑TU. At last, leaf nitrogen contents models were used to describe the quantitative impacts on the leaf morphogenesis under different levels of organic fertilizer. The model was validated with independent field experiment datas and the results showed that the mean RMSEs of internode length, leaf angle under different∑TU were 0.21 cm, 4.34°.Greenhouse muskmelon fruit growth morphology simulation model is one of the important parts to achieve the greenhouse melon aerial part growth model and also the first important step to success in getting fruit VR model.In this research, muskmelon(Cucumis melo var.reticulatus Naud.) fruit morphology growth was automatically recorded by digital camera by non-destructive method at fixed point from time to time during the whole period of fruit growth and development period. At last, temperature-driven Logistic mathematical model was built to simulate the of muskmelon fruit dynamic growth process and was validated by separated abserved data. The result showed that the RMSE of fruit longitudinal and equatorial diameter was 0.263 cm,0.174 cm.