摘要
采用蛭石栽培,以耐盐性不同的2个菜用大豆[Glycine max(L.)Merr.]品种为试材,研究外源壳聚糖对NaCl胁迫下幼苗叶片光合及叶绿素荧光参数的影响,探讨外源壳聚糖调控菜用大豆光合作用的生理机制。结果显示:(1)外源壳聚糖通过诱导非气孔因素显著缓解了盐敏感品种‘理想高产95-1’(LX)在胁迫第6、9、12天时净光合速率(Pn)的下降,但胁迫第15天该作用消失;通过同时诱导气孔因素和非气孔因素缓解了耐盐品种‘绿领特早’(LL)在胁迫第3、6天时Pn的下降,其后Pn下降的缓解则主要通过诱导非气孔因素实现,且LL的Pn较盐处理的增幅均高于同期的LX。(2)外源壳聚糖阻止了LX在盐胁迫第12天、LL在胁迫第15天时非光化学猝灭系数(NPQ)的下降;外源壳聚糖显著缓解了LL在盐胁迫第15天时光化学猝灭系数(qP)、实际光化学效率(ФPSⅡ)的下降。(3)无盐条件下,外源壳聚糖在处理早期通过诱导气孔导度(Gs)、qP及ФPSⅡ等气孔和非气孔因素显著提高了两品种菜用大豆的Pn,但中、后期该作用消失。研究表明,菜用大豆具有潜在的抗逆性,外源壳聚糖在NaCl胁迫下对菜用大豆的作用与无盐条件下不同;壳聚糖只有在菜用大豆受到盐胁迫伤害时才可诱导其潜在的抗盐性,但其诱导途径、诱导时效、诱导效果因品种耐盐性不同而异;耐盐品种LL具有较强、持久且多元的潜在抗逆能力,这可能是其经壳聚糖诱导后能维持相对较高Pn的重要原因之一。
In order to investigate the physiological regulation mechanism of exogenous chitosan on vegetable soybean photosynthesis,we studied the effects of exogenous chitosan on photosynthetic and chlorophyll fluorescence parameters in seedling leaves of two vegetable soybean [Glycine max (L.) Merr.] cultivars with different salt tolerance under NaCl stress by adopting vermiculite culture.The results showed:(1)exogenous chitosan alleviated the decline of net photosynthetic rate (Pn) of salt-sensitive cultivar LX markedly at the 6th,9th and 12th days of salinity by inducing non stomatal factors,but this effect disappeared after 15 days of salt stress.For salt-tolerant cultivar LL,chitosan reduced the decline of Pn significantly at the 3rd and 6th days of salinity by inducing stomatal factors and non stomatal factors simultaneously,and reduced that of the 9th,12th and 15th days of salt treatment mainly by inducing non stomatal factors,and its growth of Pn compare with NaCl treatment were higher than that of LX.(2)Exogenous chitosan prevented the decline of non photochemical quenching coefficient (NPQ) of LX after 12 days of salinity,and prevented the decline of NPQ and markedly alleviated the decline of photochemical quenching coefficient (qP) and actual photochemical efficiency (ФPSⅡ) of LL after 15 days of salinity.(3)Under no NaCl condition,chitosan increased the Pn of two vegetable soybean cultivars significantly by inducing stomatal factors and non stomatal factors such as stomatal conductance (Gs),qP and ФPSⅡ at the early stage of spraying chitosan,but these effects disappeared at middle and later stage.All the results suggest that:vegetable soybean has potential resistance.The effects of exogenous chitosan on vegetable soybean under NaCl stress differ from those of no NaCl condition.Chitosan can only induce potential salt resistance of vegetable soybean when it is injured by salt stress.However,the induction route,induction timeline and induction effect of chitosan on vegetable soybean were different because of different salt tolerance of vegetable soybean.The salt tolerant cultivar LL has strong,durable and multiple potential resistance ability,which may play an important role in maintaining relatively higher Pn induced by chitosan.
出处
《西北植物学报》
CAS
CSCD
北大核心
2015年第6期1198-1205,共8页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金(31260472
31260483)
内蒙古民族大学科研创新团队计划(NMD1003)
关键词
外源壳聚糖
NACL胁迫
菜用大豆
不同品种
光合作用
exogenous chitosan
NaCl stress
vegetable soybean
different varieties
photosynthesis