Effects of 6-BA on the growth and photosynthetic characteristics of two cultivars of cucumber seedlings under low light environment

XUN Tianzhuo; HU Haoxiang; TAO Zhe; LAN Xin; LI Wenwen; XU Hongjun; SUN Yanru; ZHANG Weihua; JIA Kai

doi:10.16861/j.cnki.zggc.2024.0676

Abstract：To mitigate the effects of low-light stress on vegetable seedlings in spring production,the cucumber light-sensitive variety Ruixiangmici and the low-light-tolerant variety Jinshun A4 were used as test materials,and set up normal light(500 μmol·m-2·s-1)in the light incubator as the normal light control CK1,and the low light environment(80-100 μmol·m-2·s-1)in the daylight chamber of Xinjiang Agricultural University as the low light control CK2.After the cotyledons unfolded at 7 d of seedling age,different concentrations of 6-BA solution(40,60,80 mg·L-1)were sprayed on the foliage to analyze the effects of different treatments on cucumber seedling growth,seedling growth index,and photo-synthesis indexes under low-light environment.The results showed that the two varieties of cucumber showed the same performance in growth indexes and photosynthetic characteristics.Compared with the low-light control,spraying differ-ent concentrations of 6-BA inhibited plant height elongation,increased stem thickness,maximum leaf area,root length,aboveground dry and fresh mass,root dry and fresh mass,and seedling index,and increased the relative content of chlorophyll,photosynthetic gas exchange parameters,and chlorophyll fluorescence parameters,among which,Ruixiangmici and Jinshun A4 treated with 80 mg·L-1 6-BA were more effective in the growth indexes.Ruixiangmici and Jinshun A4 seedlings sprayed with 80 mg·L-1 6-BA increased significantly the strong seedling index by 13.79％and 80.77％,and the net photosyn-thetic rate by 65.92％and 19.65％,respectively.After the comprehensive analysis of the affiliation function,the concentra-tion of 80 mg·L-1 of 6-BA had the best effect on the mitigation of cucumber seedling growth under low light environment.