Study On Lighting Technology For Greenhouse

Factory rice Seedling nursing is an important part of realizing mechanization of rice production.Factory stereoscopic seedling nursing has got incresing attention in recent years because of the advantages of space utilization,high production efficiency,and the ability to cultivate high quality seedlings suitable for mechanized transplanting.However,the mutual occlusion between the seedling frame lead to a insufficient lighting,thus affects the quality of the seedlings seriously.In most places,lighting technology was used to improve filling conditions in stereoscopic seedling frame to ensure the quality of seedlings.Therefore,to study the technique of greenhouse stereoscopic seedling nursing,and to develop a mobile lighting platform,will have an important guiding significance for greenhouse stereoscopic seedling nursingStudy on stereoscopic seedling nursing in the field of horticultural production has been widely used both in China and abroad.However,the research on light quality,light intensity,red-to-blue-light-ratio and light time is mainly onflowers,vegetables and other crops.While research in filling technology in greenhouse stereoscopic rice seedling nursing is relatively small.Inthis paper,the theory of natural light and Ecotect software was adopt to analysis the light environment of different seedling frames in greenhouse.Orthogonal test was used to study the light environment,filling technology and Mobile filling platform of greenhouse stereoscopic seedling nursing,thus to optimize the filling conditions of seedlings in different seedling frames and seedling layers.According to the filling characteristics.a mobile filling platform was developed to achieve accurate light control on seedlings.The main research contents and conclusions are as follows:(1)The theoretical analysis and calculation of artificial filling in greenhouse were finished.Simulation analysis on the light environment of different seedling frame placement was done with Ecotect software.The light environment of different seedling frame placement in the greenhouse were calculated respectively,thus provide a theoretical reference for the greenhouse rice filling test and the development of mobile filling platform.According to the plant optical theory of plant physiology,the red-to-blue-light-ratio,light intensity and photoperiod required for plant growth was analyzed.According to the analysis and calculation,the annual average illuminance in the greenhouse was 12221 lx.Simulation analysis on the light environment of different seedling frame placement was done with Ecotect software.analysis the light environment in different positions comprehensively,get the illumination range of different location of seedling frame in greenhouse seedling frame,proves the necessity of light greenhouse seedling of stereo,provide the basis for subsequent seedling test.(2)For the parallel arrangement of seedling frame,experimental research on the effect of different layers,filling time,seedling varieties and sowing amount on greenhouse stereoscopic rice seedling nursing quality test was finished,and the filling conditions in each layer of seedling frame was figure out.For the parallel arrangement of seedling frame,using L9(34)orthogonal test,with the seedling layer,fill time,seedling varieties and sowing quantity as experiment factors,filling experiments were carried out.Test results show that according to the seedling index,The order of the factors are:filling time>sowing quantity>seedling varieties>seedling layer,Among them,the effect of seedling layer and seedling varieties are small,while the effect of filling time and sowing quantity are big and close to each other.decreased with increase of filling time and the decrease of sowing rate,seedling index increased gradually.For the second layer and third layer of seedling frame,the light intensity of 25001x,night filling time is 4h and 3h.The first layer(bottom layer)should use the light intensity of 30001x,night filling time of 5h,thus to ensure the quality of hybrid rice under low sowing quantity,so as to meet the Technical requirements for mechanized transplanting.This will provide guidance for the greenhouse stereoscopic rice seedling nursing production and application.(3)For the inside and outside arrangement of seedling frame,experimental research on the effect of different seedling positions,seedling layers,seedling varieties and filling time on greenhouse stereoscopic rice seedling nursing quality test was finished,and the filling conditions in each layer of different seedling frame was obtained.In the inside and outside arrangement of seedling frame,using L9(34)orthogonal test method,with the seedling frame positions,seedling layers,varietis and filling time as the test factors,filling experiments were carried out.Test results show that according to the seedling index,The order of the factors are:filling time>frame positions>varieties>seedling layers,when the light intensity is 30001x,the seedlings on the outside frame require a night filling time of 3h,the seedlings on the button layer of the internal frame require a night filling time of 5h to achieve the requirements of seedling mechanized transplanting.For the seedling tray on the outside frame,vertical placement is better for the seedlings to grow more evenly than horizontal placement,thus to improve the blanket property of seedlings,so as to meet the requirements of mechanized transplanting,which can provide a reference for the industrialized greenhouse stereoscopic seedling nursing.(4)A mobile filling platform was developed to achieve accurate filling control on both time and position.Test shows that the mobile filling platform can achieve a same effect of multiple lamps.A mobile filling platform with the Arduino Uno development board as control core was developed.Including structure design and control system design,step motor and ball screw were used as the main structure of this platform,and the program design was completed with Arduino IDE software.Control system test shows that the platform has a stable performance,high reliability,and can achieve accurate filling control on both time and position according to the actual demand.The filling effect of mobile platform has no significant difference compared to filling by multiple lamps,and the seedlings can meet the requirements of production.This may help to reduce the capital investment.