Plasticity of photorespiratory carbon concentration mechanism in Sedobassia sedoides(Pall.)Freitag&G.Kadereit under elevated CO_(2)concentration and salinity  

作　　者：Zulfira RAKHMANKULOVA Elena SHUYSKAYA Maria PROKOFIEVA Kristina TODERICH Pavel VORONIN 

机构地区：[1]Timiryazev Institute of Plant Physiology,Russian Academy of Sciences,Moscow 127276,Russia [2]Graduate School of Bioresources,Mie University,1577 Kurimamachiya,Tsu 514-8507,Japan

出　　处：《Journal of Arid Land》2024年第7期963-982,共20页干旱区科学（英文版）

基　　金：partially supported by the Science and Technology Research Partnership for Sustainable Development(SATREPS);in collaboration with the Japan Science and Technology Agency(JPMJSA2001);the state assignment of Ministry of Science and Higher Education of the Russian Federation(122042700044-6).

摘　　要：Rising atmospheric CO_(2)(carbon dioxide)concentrations and salinization are manifestations of climate change that affect plant growth and productivity.Species with an intermediate C_(3)-C_(4)type of photosynthesis live in a wide range of precipitation,temperature,and soil quality,but are more often found in warm and dry habitats.One of the intermediate C_(3)-C_(4)photosynthetic type is C_(2)photosynthesis with a carbon concentration mechanism(CCM)that reassimilates CO_(2)released via photorespiration.However,the ecological significance under which C_(2)photosynthesis has advantages over C_(3)and C_(4)plants remains largely unexplored.Salt tolerance and functioning of CCM were studied in plants from two populations(P1 and P2)of Sedobassia sedoides(Pall.)Freitag&G.Kadereit Asch.species with C_(2)photosynthesis exposed to 4 d and 10 d salinity(200 mM NaCl)at ambient(785.7 mg/m^(3),aCO_(2)and elevated(1571.4 mg/m^(3),eCO_(2))CO_(2).On the fourth day of salinity,an increase in Na+content,activity catalase,and superoxide dismutase was observed in both populations.P2 plants showed an increase in proline content and a decrease in photosynthetic enzyme content:rubisco,phosphoenolpyruvate carboxylase(PEPC),and glycine decarboxylase(GDC),which indicated a weakening of C_(2)and C_(4)characteristics under salinity.Treatment under 10 d salinity led to an increased Na^(+)content and activity of cyclic electron flow around photosystem I(PSI CEF),a decreased content of K^(+)and GDC in both populations.P1 plants showed greater salt tolerance,which was assessed by the degree of reduction in photosynthetic enzyme content,PSI CEF activity,and changes in relative growth rate(RGR).Differences between populations were evident under the combination of eCO_(2)and salinity.Under long-term salinity and eCO_(2),more salt-tolerant P1 plants had a higher dry biomass(DW),which was positively correlated with PSI CEF activity.In less salt-tolerant P2 plants,DW correlated with transpiration and dark respiration.Thus,S.sedoides showed a high degre

关 键 词：photosystemsⅠandⅡ carbon-concentrating mechanism glycine decarboxylase RUBISCO phosphoenolpyruvate carboxylase(PEPC) cyclic electron flow salinity stress DRYLANDS 

分 类 号：P467[天文地球—大气科学及气象学] Q945[生物学—植物学]