钠盐和氯化物对真盐生植物盐地碱蓬营养生长的影响

Effects of sodium salt and chloride on vegetative growth of euhalophyte Suaeda salsa

200mmol·L^(-1)NaCl显著促进真盐生植物盐地碱蓬(Suaeda salsa)的营养生长,但具体是Na^+、Cl^-还是二者共同起作用尚不清楚。本文分别采用0、200mmol·L^(-1)NaCl以及相同浓度的钠盐(由NaNO_3、NaH_2PO_4、Na_2SO_4组成)、氯化物(由MgCl_2、KCl、CaCl_2、NH_4Cl组成)自种子播种开始处理盐地碱蓬,对植株的生物量、离子含量、光合和荧光等营养生长相关参数进行研究,结果表明:200mmol·L^(-1)NaCl和钠盐处理显著增加盐地碱蓬的株高、分枝数、干鲜重等,其中200mmol·L^(-1)钠盐处理的促进作用最显著;而200mmol·L^(-1)氯化物处理显著抑制了盐地碱蓬的营养生长,植物矮小,黄化严重。进一步研究发现NaCl和钠盐处理显著增加了盐地碱蓬叶片中叶绿素含量,提高了植株净光合速率;而同浓度氯化物处理降低了盐地碱蓬叶片中叶绿素含量,其净光合速率显著下降。以上结果表明:Na^+通过促进光合作用促进稀盐型盐生植物盐地碱蓬的营养生长,而Cl^-有抑制作用。

NaCl（200 mmol·L^（-1））significantly promotes the vegetative growth of euhalophyte Suaeda salsa.However,the single effects of sodium and chloride are still unclear.To investigate the roles of sodium and chloride on the vegetative growth of S.salsa,plant biomass,ion content,chlorophyll content,photosynthesis and fluorescence parameters were determined under the conditions of control,200 mmol·L^（-1） Na Cl,200 mmol·L^（-1）sodium salt（composed of Na NO_3,NaH_2PO_4 and Na_2SO_4）and 200 mmol·L^（-1） chloride（composed of MgCl_2,KCl,CaCl_2 and NH_4Cl）,respectively.The results show that the plant height,fresh weight,dry weight and branch number of S.salsa were significantly promoted by Na Cl and sodium salt treatments,while inhibited by chloride treatment.Further experiments indicate that the content of chlorophyll,net photosynthetic rate,Φ_（PSII）and F_v/F_m of S.salsa were also markedly increased when treated by NaCl and sodium salt,and significantly decreased by 200 mmol·L^（-1） chloride treatment.The results indicate that Na~＋was the main factor to promote the vegetative growth of S.salsa via improving the photosynthesis parameters.