LED光源不同光强对冀星9号辣椒幼苗生长和光合特性的影响

Effects of Different LED Light Intensities on Growth and Photosynthetic Characteristics of Jixing-9 Pepper Seedlings

本试验以冀星9号牛角椒2叶1心幼苗为试验材料,以自然光为对照(CK),在红光∶蓝光=5∶1的光质配比条件下,研究了不同光强[80、120、160、200μmol/(m^(2)·s)]对辣椒幼苗生长和光合特性的影响。结果表明:与CK相比,不同光强LED处理20 d和30 d后,幼苗株高显著降低;光强为120、160μmol/(m^(2)·s)时,幼苗茎粗、叶面积、地下部鲜重、地上部干重、根长、根尖数、根系活力和光合色素含量等指标均表现较优;光强为120、160μmol/(m^(2)·s)时幼苗净光合速率、光强为160μmol/(m^(2)·s)时幼苗气孔导度和蒸腾速率均高于其他处理;光强为120、160、200μmol/(m^(2)·s)时,壮苗指数较高。综合分析,LED光源光强为120、160μmol/(m^(2)·s)时较利于辣椒幼苗生长。

In this experiment,Jixing-9 pepper seedlings at 2 leaves stage were used as the experimental materials,and natural light was used as the control,the effects of different light intensities[80,120,160 and 200μmol/(m^(2)·s)]on the growth and photosynthetic characteristics of pepper seedlings were studied at the light quality ratio of red light∶blue light=5∶1.The results showed that compared with the CK,the seedling height decreased significantly after LED treatment for 20 and 30 days.When the light intensity was 120 and 160μmol/(m^(2)·s),the indexes of seedlings such as stem diameter,leaf area,fresh weight of underground parts,dry weight of aboveground parts,root length,root tip number,root activity and photosynthetic pigment content were better.The net photosynthetic rate of seedlings under light intensity of 120 and 160μmol/(m^(2)·s)and the stomatal conductance and transpiration rate of seedlings under light intensity of 160μmol/(m^(2)·s)were higher than those of other treatments.When the light intensity was 120,160 and 200μmol/(m^(2)·s),the healthy seedling index was higher.Comprehensive analysis showed that when the light intensity of LED light source was 120 and 160μmol/(m^(2)·s),it was more beneficial to the growth of pepper seedlings.