自然干旱胁迫对米槁幼苗叶片显微结构及叶绿素含量的影响

Effect of Natural Drought Stress on Microstructure and Chlorophyll Content of Cinnamomum migao H.W.Li Seedlings

以一年生米槁为试材,在为期22d的自然失水胁迫处理下,研究了米槁生长形态、叶形态解剖结构以及光合色素在不同胁迫时间下的变化特点,以期探讨米槁幼苗对持续干旱胁迫的适应能力及对策。结果表明:随着胁迫时间的增加,其生长指标受显著抑制;叶绿素a、b含量呈先降低后升高再降低的趋势,但叶绿素a/b的趋势相反,类胡萝卜素含量先下降后上升;叶片厚度、上表皮细胞厚度、叶脉周长和面积呈先下降后上升趋势;海绵组织厚度呈上升的趋势,栅栏组织厚度和叶片组织结构紧密度(CTR)呈先下降后上升的趋势。表明米槁在干旱胁迫时可以通过改变叶片内组织结构来提高其抗旱性。

Taking the annual Cinnamomum migao H.W.Li as material,in a period of 22 days natural drought stress treatment,the effect of different stress time on growth,leaf anatomical characteristics and photosynthetic pigment contents of Cinnamomum migao H.W.Li were studied,in order to assess the ability and countermeasure of tolerating drought in the species.The results showed that with increasing stress time,their growth targets was significantly inhibitted;Chl a and Chl b increased after the first decreased and then decreased,Chl a/b opposited and Car first declined then increased;leaf thickness,the thickness of the skin,veins perimeter and area decresed at first and then increased;spongy tissue upward,and palisade tissue and CTR decresed at first and then increased.The study showed that Cinnamomum migao H.W.Li during drought stress could improve its drought resistance by changing the organizational structure of the blade.