利用砂培试验研究了不同氮素形态对向日葵生长和光合功能的影响.结果表明:NO3- - N NN 处理的株高、叶面积、干物质重显著高于NH4 + - N AA 处理,施用NO3- - N的植株有较高的净光合速率 Pn 和较低的气孔导度 Cs 、细胞间隙CO2 浓度 Ci ...利用砂培试验研究了不同氮素形态对向日葵生长和光合功能的影响.结果表明:NO3- - N NN 处理的株高、叶面积、干物质重显著高于NH4 + - N AA 处理,施用NO3- - N的植株有较高的净光合速率 Pn 和较低的气孔导度 Cs 、细胞间隙CO2 浓度 Ci .不同处理之间Fv/ Fm没有显著差异,NN处理的植株PS 线性电子传递量子效率ΦPS 、光化学荧光猝灭系数q P和表观光合电子传递效率ETR都显著高于AA处理的植株;而非光化学荧光猝灭系数q N则明显低于AA处理的植株.碳同化受到抑制是NH4 + - N条件下净光合速率下降的重要原因.展开更多
Acid rain(AR),which occurs frequently in southern China,negatively affects the growth of subtropical tree species.Arbuscular mycorrhizal fungi(AMF)mitigate the detrimental effects induced by AR.However,the mechanisms ...Acid rain(AR),which occurs frequently in southern China,negatively affects the growth of subtropical tree species.Arbuscular mycorrhizal fungi(AMF)mitigate the detrimental effects induced by AR.However,the mechanisms by which AMF protect Zelkova serrata,an economically important tree species in southern China,from AR stress remain unclear.We conducted a greenhouse experiment in which Z.serrata plants were inoculated with AMF species Rhizophagus intraradices and Diversispora versiformis,either alone or as a mixed culture,or with a sterilized inoculum(negative control).The plants were subjected to three levels of simulated sulfuric AR and nitric AR(pH 2.5,4.0 and 5.6)to examine any interactive effects on growth,photosynthetic capabilities,antioxidant enzymes,osmotic adjustment and soil enzymes.AR significantly decreased dry weight,chlorophyll content,net photosynthetic rate and soluble protein(SP)of non-mycorrhizal plants.Mycorrhizal inoculation,especially a combination of R.intraradices and D.versiformis,notably improved dry weight,photosynthetic capabilities,catalase,peroxidase,superoxide dismutase,SP and root acid phosphatase activity of Z.serrata under harsh AR stress.Moreover,the benefits from AMF symbionts depended on the identity of AM fungal species and the gradient of AR stress.Our results indicate that AM fungi protect z.serrata against AR stress by synchronously activating photosynthetic ability,antioxidant enzymes and osmolyte accumulation.These findings suggest that a combination of R.intraradices and D.versiformis may be a preferable choice for culturing Z.serratain southern China.展开更多
基金the National Natural ScienceFoundationofChina(32071644and 31400366)the Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(LTY22C030003)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB 31030000)the Special Foundation for National Science and Technology Basic Research Program of China(2019FY102000)the Key Research and Development Plan of Zhejiang Province(2017C02028).
文摘Acid rain(AR),which occurs frequently in southern China,negatively affects the growth of subtropical tree species.Arbuscular mycorrhizal fungi(AMF)mitigate the detrimental effects induced by AR.However,the mechanisms by which AMF protect Zelkova serrata,an economically important tree species in southern China,from AR stress remain unclear.We conducted a greenhouse experiment in which Z.serrata plants were inoculated with AMF species Rhizophagus intraradices and Diversispora versiformis,either alone or as a mixed culture,or with a sterilized inoculum(negative control).The plants were subjected to three levels of simulated sulfuric AR and nitric AR(pH 2.5,4.0 and 5.6)to examine any interactive effects on growth,photosynthetic capabilities,antioxidant enzymes,osmotic adjustment and soil enzymes.AR significantly decreased dry weight,chlorophyll content,net photosynthetic rate and soluble protein(SP)of non-mycorrhizal plants.Mycorrhizal inoculation,especially a combination of R.intraradices and D.versiformis,notably improved dry weight,photosynthetic capabilities,catalase,peroxidase,superoxide dismutase,SP and root acid phosphatase activity of Z.serrata under harsh AR stress.Moreover,the benefits from AMF symbionts depended on the identity of AM fungal species and the gradient of AR stress.Our results indicate that AM fungi protect z.serrata against AR stress by synchronously activating photosynthetic ability,antioxidant enzymes and osmolyte accumulation.These findings suggest that a combination of R.intraradices and D.versiformis may be a preferable choice for culturing Z.serratain southern China.
