摘要
以‘武川’和‘浑源’2个蒙古黄芪地方品种为试材,采用盆栽控水模拟干旱处理,研究干旱胁迫下黄芪生物量及根际微生物数量的动态变化规律。结果显示:随着干旱程度的加剧,2个品种的根际细菌和放线菌种群数量均呈先上升后下降的变化趋势,真菌数量却呈现持续减少,而细菌数量在根际微生物区系中占绝对优势;随干旱强度升高,2个品种黄芪根、叶组织相对含水量均表现出明显的逐渐下降趋势,其地上部生物量、根系生物量也均降低,而根冠比却逐渐增大;黄芪根际各菌类数量与其地上生物量存在显著正相关关系,但与根系生物量无显著相关关系。研究表明,黄芪的生长及其根际微生物数量均受到干旱胁迫的影响,且适度干旱有助于提高黄芪根际细菌及放线菌的数量,从而改变根际微生物群落结构组成,促进黄芪地上生物量的积累。
The experiment was conducted in pot with‘Wuchuan＇and‘Hunyuan＇（biennial Astragalus mongholicus at greenhouse in Inner Mongolia University.The dynamic of rhizosphere microbial quantity and biomass on the two cultivars under continuous drought was studied through artificially controlling soil water content to stimulate drought condition.The results show that there are the obvious differences in bacteria,actinomycetes and fungi,and the microbial flora composition is dominated by bacteria,and then actinomycets.And along with continuous drought stress,bacteria and actinomycete amounts in the rhizosphere soil of two cultivar A.mongholicusfirst increased then decreased.However,the fungus amounts in the rhizosphere soil of A.mongholicus decreased continually comparing to the control.At the same time,the growth of A.mongholicus was inhabited by drought stress.The biomass in aboveground and roots parts of two cultivars A.mongholicus,root and leaf tissue relative water content all declined but R/S-ratio increased with the increase of drought intensity.Correlation analysis showed that the number of rhizosphere soil microbe had a significant positive correlation with aboveground biomass,but weak relation with roots biomass.The results indicated that the moderate drought improved the quantities of bacteria and actinomycetes,thereby altering the microbial community structure,which is beneficial to the accumulation of aboveground biomassof A.mongholicus.
出处
《西北植物学报》
CAS
CSCD
北大核心
2015年第9期1868-1874,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金(81460578)
内蒙古自然科学基金(2014MS0308)
关键词
黄芪
干旱胁迫
根际
微生物
生物量
Astragalus mongholicus
drought stress
rhizosphere
microbe
biomass
