鱼腥草幼苗叶片结构和光合荧光特性对不同光质的响应

Response of leaf structure and photosynthetic fluorescence characteristics of Houttuynia cordata Thund. seedlings to different lights

以4种不同光质(红光、蓝光、黄光、绿光)为光源(白光为对照),研究出苗后30 d和60 d的鱼腥草幼苗叶片结构和光合荧光特性对不同光质的响应。结果表明:与CK相比,黄光、蓝光、红光处理下鱼腥草幼苗的叶片厚度及叶片的上表皮、下表皮、栅栏组织、海绵组织厚度均有不同程度的增加,而绿光处理下的却表现为降低;与30 d的幼苗相比,60 d幼苗的叶片厚度在蓝光处理下的增幅最大;蓝光处理下鱼腥草幼苗叶片的叶绿素a、叶绿素b和叶绿素总含量均表现最高,白光处理的次之,绿光处理的最小;在不同光质下,幼苗叶片的光合速率呈显著性差异;蓝光处理下的光合荧光参数(F0、Fm、qP和NPQ)均大于白光处理的,说明蓝光处理最有利于鱼腥草叶片结构和光合荧光特性的改善。

To understand the response of leaf structure and photosynthetic characteristics of seedlings to different light,we apply four LED lights,red,blue,yellow,green as the light source to30d and60d Houttuynia cordata Thund.Seedlings.Compared with that treated by white light(CK),the leaf structure under yellow light,blue light and red light treatments showed advantages in leaf thickness,upper epidermis and lower epidermis thickness,palisade tissue and spongy tissue thickness,while that treated by green light displayed disadvantages.And compared with30d seedlings growth,the increment of leaf structure on60d seedlings by blue light was most among all the treatments.The increment of mount of chlorophyll a,chlorophyll b and total chlorophyll under the blue light treatment was the highest followed by the treatments of white,yellow,red,and green light.Seedling leaf photosynthetic rate showed significant differences under different lights,the photosynthetic fluorescence parameters(F0,Fm,qP and NPQ)of seedlings under blue light treatment were greater than those of white light treatment,which indicated blue light treatment was most suitable for enhancing leaf structure and photosynthetic fluorescence characteristics of Houttuynia cordata Thunb.