论文部分内容阅读
【目的】分析Na Cl处理下一年生黑桑移栽苗叶片的光合作用及叶绿素荧光参数的变化,研究一年生黑桑移栽苗的耐盐特性,为黑桑在盐碱地的推广应用提供理论依据。【方法】以一年生黑桑移栽苗为材料进行不同程度的Na Cl处理,Na Cl处理浓度为0、50、100、150、200、250、300 mmol/L,在加Na Cl处理后的第12 d测定不同Na Cl处理的黑桑叶片光合生理指标和叶绿素荧光参数,选择生长一致的一年生黑桑移栽苗并挂牌定株,统一选择植株的第4片完全叶(也挂牌做标记)进行测定,每个处理分别测定5株。【结果】低浓度盐分(Na Cl为50 mmol/L)对一年生黑桑移栽苗的PSⅡ光化学量子效率(ΦPSⅡ)、光化学猝灭系数(q P)、电子传递速率(ETR)和激发能捕获效率(Fv’/Fm’)无显著影响;高浓度盐分(Na Cl≥100 mmol/L)导致叶片净光合速率(Pn)、气孔导度(Gs)、电子传递速率(ETR)、激发能捕获效率(Fv’/Fm’)、PSⅡ光化学量子效率(ΦPSⅡ)、光化学猝灭系数(q P)均下降,胞间CO2浓度(Ci)的提高。【结论】一年生黑桑移栽苗在50 mmol/L Na Cl处理下生长良好,其光合荧光特性没有受到影响。在100、150 mmol/L Na Cl处理下,其光合荧光特性虽受到抑制,但仍维持有较高的光合净积累,一年生黑桑移栽苗受到的伤害较轻且仍能存活。在200、250、300 mmol/L Na Cl处理下,一年生黑桑移栽苗受到的伤害较严重,尤其是250、300 mmol/L Na Cl处理下,其叶片干枯萎蔫严重,并脱落。随着Na Cl浓度的增加,引起一年生黑桑移栽苗光合速率下降的原因是逐渐由气孔限制转向非气孔限制,光合参数、叶绿素荧光参数的变化与黑桑的抗性及盐浓度密切相关。
【Objective】 The objective of this study was to analyze the photosynthesis and chlorophyll fluorescence parameters of the leaves of annual black transplanted seedlings under NaCl treatment and to study the salt tolerance of annual black mulberry transplanting seedlings and to provide a theoretical basis for the popularization and application of black mulberry in saline-alkali soil. 【Method】 One-year old black mulberry transplanting seedlings were treated with different concentrations of Na Cl. The concentrations of Na Cl were 0, 50, 100, 150, 200, 250 and 300 mmol / L. The photosynthetic physiological parameters and chlorophyll fluorescence parameters of black mulberry leaves treated with different NaCl were measured on the 12th day. One-year-old black mulberry transplanting seedlings with the same growth were selected and screened. The fourth leaf of the plant was also selected (labeled) Five strains were measured for each treatment. 【Result】 The results showed that PSⅡ photochemical quantum efficiency (ΦPSⅡ), photochemical quenching coefficient (q P), electron transfer rate (ETR) and excitation energy of one-year old black mulberry transplanting seedlings under low NaCl concentration (NaCl 50 mmol / L) (Fv ’/ Fm’). High concentrations of salt (Na Cl ≥100 mmol / L) led to the changes of net photosynthetic rate (Pn), stomatal conductance (Gs), electron transfer rate (Fv ’/ Fm’), PSⅡ photochemical quantum efficiency (ΦPSⅡ), photochemical quenching coefficient (q P) decreased and intercellular CO2 concentration (Ci) increased. 【Conclusion】 One-year-old black mulberry transplanting seedlings grew well under 50 mmol / L NaCl treatment, and their photosynthetic fluorescence characteristics were not affected. Under the conditions of 100 and 150 mmol / L NaCl, the photosynthetic fluorescence characteristics were inhibited, but the photosynthetic net photosynthesis still maintained a high net accumulation, and annual black mulberry transplanting seedlings were less damaged and survived. Under 200, 250 and 300 mmol / L NaCl treatment, annual black mulberry transplanting seedlings were harmed seriously, especially 250 and 300 mmol / L NaCl, their leaves wilted and wilted. With the increase of NaCl concentration, the reason of decrease of photosynthetic rate of annual black mulberry transplanting seedlings was gradually shifted from stomatal limitation to non-stomatal limitation. The changes of photosynthetic parameters and chlorophyll fluorescence parameters were closely related to the resistance and salt concentration of black mulberry.