文献类型：期刊文献

英文题名：The Positive Effect of Different 24-epiBL Pretreatments on Salinity Tolerance in Robinia pseudoacacia L. Seedlings

作者：Yue, Jianmin[1,2] Fu, Zhiyuan[1] Zhang, Liang[1] Zhang, Zihan[1,3,4] Zhang, Jinchi[1]

第一作者：Yue, Jianmin

通信作者：Zhang, JC[1]

机构：[1]Nanjing Forestry Univ, Coinnovat Ctr Sustainable Forestry Southern China, Key Lab Soil & Water Conservat & Ecol Restorat, 159 Longpan Rd, Nanjing 21037, Jiangsu, Peoples R China;[2]Univ British Columbia, Fac Forestry, Dept Forest & Conservat Sci, 2424 Main Mall, Vancouver, BC V6T IZ4, Canada;[3]Chinese Acad Forestry, Res Inst Forestry, State Forestry Adm, State Key Lab Tree Genet & Breeding, Beijing 100091, Peoples R China;[4]Chinese Acad Forestry, Res Inst Forestry, State Forestry Adm, Key Lab Tree Breeding & Cultivat, Beijing 100091, Peoples R China

年份：2019

卷号：10

期号：1

外文期刊名：FORESTS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000458910800004)】；

基金：Financial support for this study was provided by the Jiangsu Agriculture Science and Technology Innovation Fund (Grant No. CX(17) 1004), National Special Fund for Forestry Scientific Research in the Public Interest (Grant No. 201504406), Major Fund for Natural Science of Jiangsu Higher Education Institutions (Grant No. 15KJA220004), National Foundation of Forestry Science and Technology Popularization (Grant No. [2015]17), Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and the Doctorate Fellowship Foundation of Nanjing Forestry University.

语种：英文

外文关键词：24-epiBL application; salt stress; ion contents; chloroplast ultrastructure; photosynthesis; Robinia pseudoacacia L

摘要：As a brassinosteroid (BR), 24-epibrassinolide (24-epiBL) has been widely used to enhance the resistance of plants to multiple stresses, including salinity. Black locust (Robinia pseudoacacia L.) is a common species in degraded soils. In the current study, plants were pretreated with three levels of 24-epiBL (0.21, 0.62, or 1.04 mu M) by either soaking seeds during the germination phase (Sew), foliar spraying (Spw), or root dipping (Diw) at the age of 6 months. The plants were exposed to salt stress (100 and 200 mM NaCl) via automatic drip-feeding (water content similar to 40%) for 45 days after each treatment. Increased salinity resulted in a decrease in net photosynthesis rate (P-n), stomatal conductance (G(s)), intercellular:ambient CO2 concentration ratio (C-i/C-a), water-use efficiency (WUEi), and maximum quantum yield of photosystem II (PSII) (F-v/F-m). Non-photochemical quenching (NPQ) and thermal dissipation (H-d) were elevated under stress, which accompanied the reduction in the membrane steady index (MSI), water content (RWC), and pigment concentration (Chl a, Chl b, and Chl). Indicators of oxidative stress (i.e., malondialdehyde (MDA) and antioxidant enzymes (peroxidase (POD) and superoxide dismutase (SOD)) in leaves and Na+ content in chloroplasts increased accompanied by a reduction in chloroplastid K+ and Ca2+. At 200 mM NaCl, the chloroplast and thylakoid ultrastructures were severely disrupted. Exogenous 24-epiBL improved MSI, RWC, K+, and Ca2+ content, reduced Na+ levels, maintained chloroplast and thylakoid membrane structures, and enhanced the antioxidant ability in leaves. 24-epiBL also substantially alleviated stress-induced limitations of photosynthetic ability, reflected by elevated chlorophyll fluorescence, pigment levels, and P-n. The positive effects of alleviating salt stress in R. pseudoacacia seedlings in terms of treatment application was Diw > Sew > Spw, and the most positive impacts were seen with 1.04 mu M 24-epiBL. These results provide diverse choice for 24-epiBL usage to defend against NaCl stress of a plant.