不同形态氮素对盐胁迫下番茄细胞超微结构与光合作用的影响  

Effect of Nitrogen Forms on Cell Ultrastructure and Photosynthesis of Tomato Under Salinity

作　　者：刘冉[1] 石峰[1] 刘伟成[2] 马梅[1] 李镇[1] 郭世伟[1] 郑青松[1] 郑春芳[2] 

机构地区：[1]南京农业大学资源与环境科学学院,江苏省海洋生物学重点实验室,南京210095 [2]浙江省海洋水产养殖研究所,浙江省永兴水产种业有限公司

出　　处：《园艺学报》2015年第3期471-479,共9页Acta Horticulturae Sinica

基　　金：浙江省重大科研专项(2012C12017-3);浙江省专项资金-浙江省海洋与渔业局项目计划{浙海渔计[2013(18)]};江苏省农业科技自主创新项目[CX(12)1005-04]

摘　　要：研究了在150 mmol·L^(-1) NaCl胁迫下含铵态氮、硝态氮和硝酸铵(氮素浓度均为3 mmol·L^(-1))的营养液培养的番茄幼苗生长、细胞超微结构、根系活力和光合作用参数的变化。结果表明:NaCl胁迫下,硝态氮处理叶片细胞出现伤害现象,而硝酸铵处理未见明显变化。铵态氮处理细胞超微结构明显发生破坏性变化,盐胁迫下,其伤害加剧。NaCl处理下,不同氮素形态处理下的植株生物量和根系活力均显著下降,其中硝酸铵处理的植株生物量和根系活力维持最高。NaCl胁迫下3种氮素形态处理的植株净光合速率(Pn)和蒸腾速率(Tr)均显著下降,其中硝酸铵处理的Pn和Tr要明显高于其他氮素处理。NaCl胁迫下,硝态氮处理和硝酸铵处理的水分利用效率(WUE)和气孔限制值(Ls)均明显上升,而铵态氮处理显著降低。综上,盐胁迫下,硝酸铵处理下番茄幼苗可维持较好的细胞超微结构、根系活力和较高的光合作用,维持较高的生物量,从而维持较高的耐盐性。In order to study effects of different nitrogen sources on the responses of tomato plants to salt stress,the effects of 150 mmol · L^(-1) NaCl on growth,cell ultrastructure,root vigor and photosynthesis of tomato seedlings were investigated by supplying with ammonium(3 mmol · L^(-1) nitrogen),nitrate(3 mmol · L^(-1) nitrogen)and ammonium nitrate(3 mmol · L^(-1) nitrogen)in nutrient solution. The results showed that salt-stressed leaf cells were damaged under nitrate source,but were not obviously affected under ammonium nitrate source,that leaf cell ultrastructure showed obvious damage under ammonium source,and salinity aggravate the damage. Under NaCl stress,the biomass and root vigor of plants were both significantly decreased fed with three nitrogen sources,with ammonium nitrate fed seedlings retaining the highest biomass and root vigor. It showed that salinity caused a significant decrease of Pn and Tr of all the plants fed with different nitrogen sources,and Pn and Tr of plants fed with ammonium nitrate was higher significantly than that fed with the other two nitrogen sources. The WUE and Ls of nitrate- and ammonium nitrate-fed plants were increased under salinity stress,however,those of ammonium-fed plants were decreased by salinity. To sum up,under salt stress,ammonium nitrate-fed tomato seedlings showed better leaf cell ultrastructure,higher root vigor and higher photosynthesis than nitrate-fed tomato seedlings,so that better salt tolerance was achieved. However,pure ammonium application produced greater damage or decline to cell ultrastructure,root vigor and photosynthesis,and salinity worsened these phenomena.

关 键 词：番茄 幼苗 NACL胁迫 氮素形态 细胞超微结构 光合作用 

分 类 号：S641.2[农业科学—蔬菜学]