| Digital agriculture has been the frontier realm of the modernization of agricultural production since the speed up of modern agriculture development. And it facilitates effectively the integration of agricultural production and modernized information technique, and adds fresh blood to the agricultural production. Based on the current state of the construction of digital agriculture and the need of construction and management of agriculture in China, combining with the practical demands of the processing tomato industry of Hexi Corridor of Gansu Province, Comprehensive use of computer vision technology, mathematical model analysis and fertilizer effects and so on, for the processing of tomato fruit lycopene content in rapid detection, and accumulation of simulation and effect of NPK fertilizer to provide a theoretical basis.The main results are as follows:(1) The rapid methods detecting lycopene concentration by the computer vision technology, and a unary quadratic model to predict lycopene content based on color parameters of processing tomato fruit images have been established in this study. The images of processing tomato fruits were taken in the image cameras, then the color characteristics were extracted with the PhotoshopCS4 image processing software. The correlation between color parameters of processing tomato digital image and lycopene content of processing tomato fruit were analyzed by regression models. The results showed that the color characteristics such as R,G,B,R/G,R/(G+B),r,g,b in the RGB color system, and H,I in the HIS color system were significantly correlation with lycopene content of processing tomato fruit at P<0.01. Four sets of prediction model were established and among them 1 model with high fitting degree were selected to use. The prediction accuracy of the selected model were tested, and good of fit value 0.941. According to the predict lycopene content of processing tomato fruit, the corresponding model is:LC= 9.0407-0.08G+1.211X-9.882Y+0.0002G2+0.077X2+6.564Y2。(2) To investigate accumulation characteristics of lycopene in different processing tomato varieties and screen a suitable growth equation to describe the lycopene accumulation, ten varieties were used and tested by the Richards, Logistic and Gompertz equations. The results showed that the Richards equation was more suitable for simulating lycopene accumulation process than the other growth equations in processing tomato. The Richards could improve fitting effect among the three models. Via comparing the accumulation characteristics of lycopene content in different processing tomato cultivars, the accumulation of lycopene in processing tomato could be divided into three stages, which were initial accumulation stage, fast accumulation stage and steady accumulation stage. There were two ways for processing tomato cultivars to increase lycopene content:increasing the rate of lycopene accumulation and extending the time of lycopene accumulation process.(3) The action model was established for the effects of nitrogenous, phosphatic and potassic fertilizer on the content of lycopene by using "3414" fertilizer experiment design. The effects of nitrogenous, phosphatic and potassic fertilizer on the content of lycopene in processing tomato were discussed by this model. The single factor and two-factor interaction effects of nitrogenous, phosphatic and potassic fertilizer on the lycopene content were affected by other factors. Nitrogen fertilizer has produced a positive effect to lycopene content, increasing rate became quickly as nitrogen fertilizer increased. whereas phosphor fertilizer has produced a negative effect to lycopene content, Potassic fertilizer has produced negative effect to lycopene content. Fertilizing measure to getting lycopene contents over 14 mg/100g with 95% possibility comprised nitrogen fertilizer 3.27-28.77(kg/667m2), phosphor fertilizer 7.74-22.7(kg/667m2)and potassic fertilizer 3.63-7.57(kg/667m2). |
