草业科学2024，Vol.41Issue(2)：241-251,11.DOI:10.11829/j.issn.1001-0629.2023-0013
遮阴条件下两种短命植物的叶绿素荧光特性及适应性差异
Chlorophyll fluorescence characteristics and adaptability differences of two ephemeral plants under shaded conditions
摘要
Abstract
In order to explore the photosynthetic adaptability of ephemeral plants,this paper took Malcolmia scorpioides and Arnebia decumbens as the experimental objects.The daily changes in chlorophyll fluorescence and the changes in chlorophyll content and biomass of two ephemeral plants were studied under four time gradients(0,1,7,14 d)with a shading rate of 75%.The results showed that:1)At 0 d,the maximum photochemical efficiency(Fv/Fm)and the actual photosynthetic efficiency Y(Ⅰ)and Y(Ⅱ)of the two ephemeral plants decreased significantly at mid-afternoon(14:00),showing a phenomenon of"midday photoinhibition".2)After being shaded for 1 and 7 d,the diurnal variation of photosynthetic efficiency of the two ephemeral plants showed a"single peak"curve.This increased to the peak value at 14:00,and the quantum yield of cyclic electron flow Y(CEF)increased,and the midday photoinhibition was improved.At 14 d,the quantum yield caused by PSⅠ acceptor-side limitation Y(NA)and the quantum yield of non-regulated energy dissipation in PSⅡ Y(NO)increased,the photosynthetic system was damaged,and the photosynthetic activity decreased.3)Compared with the unshaded environment,at 14:00,the photosynthetic activity of M.scorpioides decreased by 95.3%and the degree of light damage increased by 95%under shade.However,the photosynthetic activity of A.decumbens increased by 4%and heat dissipation efficiency decreased by 18.6%.4)After 14 d of shading,the chlorophyll content and biomass of the two ephemeral plants decreased,and the decline rate of M.scorpioides was higher than that of A.decumbens.In conclusion,the shade tolerance of A.decumbens is higher than that of M.scorpioides.Shading within 14 d can improve the light protection ability of A.decumbens and improve the light inhibition.Meanwhile,the improvement effect of M.scorpioideswas only within 7 d,and the photosynthetic utilization rate decreased after 7 d.关键词
光抑制/光损伤/光保护/光合效率/日变化/卷果涩芥/硬萼软紫草Key words
photoinhibition/photodamage/photoprotection/photosynthetic efficiency/diurnal variation/Malcolmia scorpioides/Arnebia decumbens引用本文复制引用
付慧蓉,李嫚,景玉婷,赵恒明,伍勇,张城铭,刘红玲,庄丽..遮阴条件下两种短命植物的叶绿素荧光特性及适应性差异[J].草业科学,2024,41(2):241-251,11.基金项目
国家自然科学基金项目(31871568、31560656) （31871568、31560656）
成都师范学院创新研究团队项目(CSCXTD2020A04) （CSCXTD2020A04）
