Effects Of Different Ratios Of Red And Blue Light On The Growth And Development Of Of Pepper Seedlings

In order to explore the influence law and mechanism of light quality on plant growth and development,and to provide scientific basis and technical support for light regulation and optimization of light environment in plant factories.In this study,using Capsicum F1 as the material,LED lamp was used as the basic light source,and different proportions of red and blue light were combined to irradiate the pepper seedlings,and the relevant physiological indexes,agronomic traits and photosynthetic characteristics of pepper seedlings under different light quality treatment were analyzed,and the main results were as follows:(1)Under T1 treatment,pepper seedlings increased significantly by 17.34% and 31.44%compared with CK leaf length and leaf area,T1 increased by 26.36% and average root diameter by 9.62% after 20 days of treatment,and the fresh weight of T1 underground part increased by 55.90% compared with the control group after 25 days of treatment,and the comprehensive ranking of T1>T3 >T2 >CK according to the comprehensive ranking of strong seedling index.(2)PAR under T1 was significantly increased by 12.11% compared with the control group,and different light quality treatments had different effects on the change of carbon dioxide concentration between cells,but there was no significant difference.T1 improves the photochemical efficiency(Fv/Fm)of the PSII reaction center of screw pepper seedlings.There were certain differences in the treatment q P values of different light quality,and the q P values were highest under T3 treatment after 30 days of treatment,while there was no significant difference between the NPQ control group and the treatment group.(3)After 25 days of treatment,the chlorophyll content of T3 was significantly reduced by 19.94% compared with the control group,the content of T1 chlorophyll b was significantly increased by 24.6% compared with the control group,and at 30 days of treatment,T1 carotenoids were significantly increased by 21.3% compared with the control group,and T2 was increased by 8.6%.With the increase of treatment days,the soluble sugar and soluble protein content of T1 pepper seedlings was significantly higher than that of other treatment groups at 20 days of treatment,and the soluble protein content of T1 pepper seedlings was significantly higher than that of other treatment groups at 20 days and 25 days of treatment,and the soluble protein content of T1 pepper seedlings was significantly higher than that of the control group at 30 days of treatment,but there was no significant difference with T2.(4)With the extension of treatment days,the activities of T1 and T3 Rubisco enzymes increased,and T1 Rubisco enzyme activities were the largest at 30 days of treatment,and T2 Rubisco enzyme activities were significantly lower than those in other treatment groups.At 25 days and 30 days of treatment,the activities of T2 and T3 PEPC enzymes were significantly higher than those in the control group,while T1 was not significantly different from the control group.The activity of T2 GAPDH enzyme was significantly lower than that of other treatment groups at 20 days of treatment,and there was no significant difference between the control group and the treatment group after 25 days and30 days of treatment.(5)Principal component analysis was carried out for 10 indicators including soluble sugars,soluble protein,chlorophyll a,chlorophyll b,carotenoids,q P,ETR,NPQ,Rubisco enzyme activity and GAPDH enzyme activity to produce an overall ranking,where the optimum light-quality ratio among the treatments set was T1(R48.6%:B20.6%:G30.8%).