摘要
以盐碱敏感型番茄品种‘中杂9号’幼苗为试验材料,研究叶面喷施0.25mmol·L-1亚精胺(Spd)对75mmol·L-1盐碱溶液胁迫下番茄幼苗生长、净光合速率及叶绿素合成前体物质含量的影响,探讨Spd在缓解番茄盐碱胁迫伤害的生理机制。结果显示:(1)盐碱胁迫下番茄叶片叶绿素合成前体物质原卟啉Ⅸ(ProtoⅨ)、镁-原卟啉Ⅸ(Mg-protoⅨ)、原叶绿素酸(Pchl)含量均显著降低,而δ-氨基酮戊酸(ALA)、胆色素原(PBG)、尿卟啉原Ⅲ(UroⅢ)显著积累,UroⅢ到ProtoⅨ的转化受阻,引起叶片叶绿素a(Chl a)、叶绿素b(Chl b)和总叶绿素(Chl)含量显著降低,以及幼苗叶片净光合速率(Pn)、叶面积、叶片相对含水量、地上和地下部干鲜重的生长指标均显著降低。(2)盐碱胁迫下,叶面喷施Spd可显著促进番茄幼苗的生长,抑制叶片内ALA、PBG、UroⅢ的积累,并提高ProtoⅨ、Mg-protoⅨ、Pchl、Chl a、Chl b、Chl含量和相应Pn值。研究表明,盐碱胁迫显著抑制番茄幼苗的生长,叶面喷施Spd可通过缓解UroⅢ到ProtoⅨ的转化受阻程度,促进盐碱胁迫下番茄叶片的叶绿素合成,提高叶绿素含量和净光合速率,减轻盐碱胁迫对幼苗生长的伤害。
With the salinity-alkalinity-sensitive tomato al,the effects of foliar-spraying Spd （0.25 mmol · L^-1 cuhivar ＇ Zhongza No. 9＇ as the experimental materi- 1） on the growth paramaters,the net photosynthetic rate （Pn） and contents of chlorophyll biosynthesis precursors in tomato seedlings grown hydroponically under 75 mmol · L^-1 mixed saline-alkaline solution were studied. The results showed that： （1）Under sa- line-alkaline stress, the contents of chlorophyll biosynthesis precursors-protoporphyrin IX （Proto IX ）, Mg- Protoporphyrin IX （Mg-Proto IX）,protochlorophyll （Pchl） were significantly decreased,while the contents of 8-aminolevulinic acid （ALA）, porphobilinogen （PBG）, uroorphyrinogen []I （Uro ]H ） were significantly accumulated in leaves of tomato seedlings. It was showed that stress restrained the transformation obstruc- tion from Uro m to Proto IX and lead to decrease in contents of Chl a,Chl b and total Chl,and reduced the Pn,leaf area,leaf relative water content, fresh and dry weight of shoot and root. （2）Under saline-alkalinestress,foliar-spraying Spd could effectively promote tomato seedlings growth and suppress the accumula- tion of ALA,PBG, URO Ⅲ and also increase contents of Proto Ⅸ, Mg-proto IX and Pchl,and enhance the Pn value. These results indicated that exogenous Spd could significantly relieve the degree of transformation obstruction from Uro Ⅲ to Proto Ⅸ, promote the tomato leaf chlorophyll synthesis and increase the chloro- phyll content and net photosynthetic rate and also alleviate the stress damage under saline-alkaline stress.
出处
《西北植物学报》
CAS
CSCD
北大核心
2015年第1期125-130,共6页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家"十二五"科技支撑计划(2011BAD29B01)
国家星火计划(2012GA850001)
西北农林科技大学校基金(QN2013018)
关键词
叶面喷施
亚精胺
番茄
盐碱胁迫
叶绿素合成前体物质
foliar-spraying
spermidine
tomato
saline-alkaline stress
chlorophyll synthesis precursor
