Response Of Cucumber And Cherry Tomato Growth To CO₂ Enrichment And LED Light Supplement In Solar Greenhouse

In Ningxia autumn,winter and early spring fruit planting in solar greenhouse,the problem of low quality and low yield of greenhouse cucumber caused by weak light and low CO₂ con centration caused by season was discussed.The effects of light intensity and CO₂ enrichment o n growth,photosynthesis,quality and yield of cucumber in solar greenhouse were studied.The cucumber ’Jindong 626’ was used as experimental material,and two experimental factors were li ght intensity and CO₂ concentration.The light intensity was set at three levels:natural light,na tural light+LED supplementary light 50 μmol/（m2 · s）and natural light+LED supplementary li ght 100 μmol/（m2·s）.CO₂ concentration:natural CO₂ concentration,400±50 μL/L and 800±50 μL/L3.The effects of different CO₂ concentration and light intensity on cucumber growth,ph otosynthetic characteristics,quality and yield were studied in order to obtain the suitable light i ntensity and CO₂ concentration conditions for cucumber cultivation in autumn and winter in sol ar greenhouse,and to provide accurate and reasonable theoretical support and technical guidance for cucumber production in facilities in the future.At the same time,the best phosgene ratio was applied to the cultivation of cherry tomato in winter solar greenhouse."Xiangfei 3" was us ed as the test material,and two treatments,natural environment treatment（CK）and CO-treatme nt of CO₂ enrichment and LED lighting（LC）,were set to explore the response of cherry tomat o to CO₂ enrichment and LED lighting.The test results are as follows:1.Interaction of CO₂ enrichment and light intensity on cucumber growth and development in solar greenhouseUnder different light intensities,100 μmol/（m2 · s）light intensities significantly promoted t he plant height,stem diameter,leaf area,root index and dry/fresh weight of overground and un derground parts of cucumber.When CO₂ concentration was 800±50 μL/L,the growth and deve lopment indexes of cucumber plants were most significantly improved.In conclusion,under the combined treatment of 100 μmol/（m2 · s）light intensity and CO₂ concentration of 800±50 μL/L,the growth and development of cucumber plants were most significantly promoted.2.Interaction of CO₂ enrichment and light intensity on photosynthetic characteristics of cuc umber in solar greenhouseUnder the same light intensity,the increase of CO₂ concentration significantly promoted the accumulation of photosynthetic pigments in cucumber leaves,and increased the net photosynthe tic rate,intercellular CO₂ concentration,maximum photochemical quantum efficiency,photochemi cal quenching coefficient and photoelectr transfer rate.Under the same CO₂ concentration,the r esponse of photosynthetic characteristics of cucumber leaves to light intensity was high light int ensity>low light intensity>natural light intensity.In conclusion,the combined treatment of 100 μmol/（m2 · s）light intensity and CO₂ concentration of 800±50 μL/L promoted photosynthes is of cucumber leaves most significantly.3.Interaction of CO₂ enrichment and light intensity on yield and quality of cucumber in s olar greenhouseUnder the combined treatment of 100 μmol/（m2 · s）and CO₂ concentration of 800±50 μL/L,the longitudinal longitude,transverse longitude,stalk length and nutritional quality of cucum ber fruits were significantly improved,and the net photosynthetic rate of cucumber leaves was promoted,and the dry matter synthesis and accumulation and yield were increased.At the same time,the yield of cucumber in winter solar greenhouse increased most significantly under this treatment.4.Effects of CO₂ enrichment and LED lighting on yield,quality and volatile compounds of cherry tomato in solar greenhouseCO₂ enrichment and LED light supplementation promoted the growth and development of c herry tomato plants,and increased the accumulation of photosynthetic pigments and net photosy nthetic rate of leaves.Compared with the natural environment,the fruit yield of cherry tomato was increased 18.18%by the treatment of the two factors at the same time.Compared with th e natural environment treatment,CO₂ enrichment and LED lighting treatment at the same time i ncreased the types and contents of volatile compounds in cherry tomato fruits to varying degree s,including 36 kinds of volatile compounds in the natural environment treatment,with a total c ontent of 2756.65 μg/g,and 55 kinds of volatile compounds in the natural environment treatme nt,with a total content of 4048μg/g.In conclusion,light intensity of 100 μmol/（m2·s）and CO₂ concentration of 800±50 μL/L were the optimal phosgene combinations for cucumber cultivation in winter solar greenhouse.E xperiments on the obtained phosgene combinations in winter solar greenhouse cultivation of che rry tomato showed that,CO₂ enrichment and LED lighting have great potential to improve the growth and development,photosynthetic characteristics,yield,fruit quality and volatile substance s of cherry tomato.