摘要
为探讨沙生植物幼苗对沙埋逆境的适应机理,以中国特有种沙芥(Pugionium cornutum L.)和濒危种斧形沙芥(P.dolabratum Maxim)为研究材料,取自然生境的沙土,采用人工模拟试验,研究沙埋对沙芥、斧形沙芥幼苗生长的影响。结果表明:遭受沙埋后,沙芥和斧形沙芥幼苗节间伸长的顺序均为T2/3>T1/2>T1/3>T0。沙埋深度在沙芥与斧形沙芥幼苗高度的1/3、1/2时,幼苗存活率100%,地上干重、总生物量、叶面积增长百分率、每天净增加的生物量和每天单位面积所固定的净光合产物均明显高于对照,根冠比显著低于对照;沙埋深度在幼苗高度2/3时,沙芥和斧形沙芥存活率分别为80%、60%,以上各指标均明显低于对照,根冠比显著高于对照;全部沙埋时,均不能成活。研究表明,沙芥、斧形沙芥幼苗对沙埋具有较强的适应性,当幼苗遭受到沙埋后,沙芥、斧形沙芥延长了节间伸长和分配较多的生物量用于地上部分的生长,这种生长方式和分配模式可能是沙芥和斧形沙芥幼苗对沙埋环境的重要适应对策。
In order to investigate the impacts of sand burial on seedling survival and growth of the species, the author took sand from natural habitats and use of indoor artificial simulation test, studied the effects of different depth sand burial on the seedling growth of P. cornutum and P. dolabratum. Results showed when the sand burial depth was up to 1/3-1/2 of their height, all the seedlings from P. cornutum and P. dolabratum could survive, and their growth characteristics which included biomass, growth percent of leaf area, RGR and NAR were significantly higher than the unburied seedlings, had lower root-top ratio. When the burial depth increased to 2/3 of their heigh, 80% of P. cornutum seedlings and 60% of P. dolabratum seedlings could survive, their growth characteristics were significantly lower than the unburied seedlings, had higher root-top ratio. No seedlings could survive when they were wholly buried in sand. Therefore, the seedlings growth of P. cornutum and P. dolabratum had strong adaptability to sand burial. When buried by sand, the seedlings extended stem and allocated more biomass for the growth of their overground part, which might be two important adaptation strategies of P. cornutum and P. dolabratum sand burial.
出处
《中国农学通报》
CSCD
2012年第7期194-198,共5页
Chinese Agricultural Science Bulletin
基金
国家自然科学基金项目"蒙古高原沙地特有属沙芥属蔬菜濒危机理及保护生物学研究"(30460080)
"蒙古高原特有属--十字花科沙芥属蔬菜植物遗传多样性研究"(30860174)
内蒙古自然科学基金项目"沙芥属植物种质保存及其适应沙漠生态环境机制研究"(20080404MS0305)
关键词
毛乌素沙地
沙芥属
沙芥
斧形沙芥
沙埋
幼苗生长
Mu Us sandy land
Pugionium Gaertn
P. cornutum
P. dolabratum
sand burial
seedling growth
作者简介
第一作者简介：黄修梅，女，1971年出生，讲师，博士，主要从事沙生蔬菜种质资源与种质创新研究。通信地址：010019内蒙古呼和浩特市新建东街275号内蒙古农业大学农学院沙生蔬菜教研室，E—mail：Huangxm0404@126．com。
通讯作者：郝丽珍，女，1960年出生，内蒙古人，教授，博士生导师，研究方向：沙生蔬菜种质资源与种质创新。通信地址：010019内蒙古呼和浩特市新建东街275号内蒙古农业大学农学院沙生蔬菜教研室，E—mail：haolizhen_1960@163．com。
