干旱胁迫及复水下朱槿生长及根际土壤微生物多样性的变化特征

Variation Characteristics of Drought and Rehydration on the Growth of Hibiscus rosa-sinensis Linn.and Soil Microbial Diversity in Rhizosphere

以朱槿品种‘紫牡丹’为试验材料,采用盆栽试验,研究了苗期重度干旱胁迫及复水对其根系生理特性的影响,并运用高通量测序技术分析干旱胁迫及复水下朱槿根际土壤微生物多样性的变化特征。结果显示:与正常处理(CK)相比,重度干旱胁迫及复水处理(T2)的总根长、根表面积及根尖数等根系生长指标呈现显著减少的结果,但与重度干旱胁迫(T1)处理相比,均显著增加。通过对朱槿根际土壤样品中细菌群落结构的研究发现,属分类水平上,厌氧绳菌属(Anaerolineaceae),酸杆菌属(Acidobacteria)、酸微菌属(Acidimicrobiales)、幽门螺杆菌属(Sphaerobacter)、链霉菌属(Streptomyces)等是不同处理土壤样品中的优势菌群。T1处理下的嗜青霉属(Algiphilus)、奥利螺旋菌属(Aureispira)、绿线菌属(Chloronema)、扁棒壳属(Acrospermum)为不同处理下的特殊细菌。真菌方面,属的分类水平上发现,粪壳菌属(Sordariale)、散囊菌属(Eurotiales)、拟青霉属(Pseudallescheria)、格孢腔菌属(Pleosporales)、枝孢霉属(Cladosporium)等是不同处理土壤样品中的优势菌群;T1和T2处理下的样品中,侧角藻属(Goniomonas)、齿盘菌属(Lamprospora)和索罗迪夫斯菌属(Sorodiplophrys)为不同处理下的特殊真菌属。其中,有促生作用的细菌如酸微菌属(Acidimicrobium)、厌氧绳菌属(Anaerolineaceae)嗜青霉属(Algiphilus)以及具有一定生防作用真菌如拟青霉属(Pseudallescheria)、枝孢霉属(Cladosporium)等均可以合理的应用在农业生产中,为植物的抗干旱胁迫以及提高朱槿在干旱胁迫下的水分利用做出贡献。

A pot experiment using a cultivar‘Purple Peony’as the experimental material was conducted under drought and rehydration condition.The effects of drought at seedling stage and rehydration on the physiological characteristics of roots and the soil microbial diversity in the rhizoshere were studied.The total root length,root surface area and root tip numbers were significantly decreased in the drought and rehydration treatment(T2),compared to the normal condition(CK),but they were significantly increased compared with the drought stress without rehydration(T1).Under drought stress(T1),Algiphilus,Aureispira,Chloronema,Acrospermum were the special bacteria.Anaerolineaceae,Acidobacteria,Acidimicrobiales,Sphaerobacter and Streptomyces were the dominant bacteria in the rhizoshpres of all drought and normal treatments.Sordariale,Eurotiales,Pseudallescheria,Pleosporales and Cladosporium were the dominant fungi.Goniomonas,Lamprospora and Sorodiplophrys were the special fungi in drought stress(T1)and rehydration after drought stress(T2).Bacteria such as Acidimicrobium,Anaerolineaceae,Algiphilus,Pseudallescheria,Cladosporium,having certain biocontrol effects,could be reasonably used in agricultural production,which could contribute to the resistance of plants to drought stress and the improvement of water use of Hibiscus under drought stress.