The osmolyte-producing endophyte Streptomyces albidoflavus OsiLf-2 induces drought and salt tolerance in rice via a multi-level mechanism
Shuqi Niu,
Yan Gao,
Huixian Zi,
Ying Liu,
Xuanming Liu,
Xianqiu Xiong,
Qingqing Yao,
Ziwei Qin,
Ning Chen,
Liang Guo,
Yuanzhu Yang,
Peng Qin,
Jianzhong Lin,
Yonghua Zhu
Affiliations
Shuqi Niu
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Yan Gao
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Huixian Zi
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Ying Liu
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Xuanming Liu
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Xianqiu Xiong
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Qingqing Yao
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Ziwei Qin
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Ning Chen
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Liang Guo
Yuan Longping High-Tech Agriculture Co., Ltd., Changsha 410001, Hunan, China
Yuanzhu Yang
Yuan Longping High-Tech Agriculture Co., Ltd., Changsha 410001, Hunan, China
Peng Qin
Yuan Longping High-Tech Agriculture Co., Ltd., Changsha 410001, Hunan, China
Jianzhong Lin
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China
Yonghua Zhu
Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410008, Hunan, China; Corresponding author.
Drought and salinity are major environmental stresses that impair crop growth and productivity worldwide. Improving drought and salt tolerance of crops with microbial mutualists is an effective and environmentally sound strategy to meet the demands of the ever-growing world population. In the present study, we found that the Streptomyces albidoflavus OsiLf-2, a moderately salt-tolerant endophytic actinomycete, produced abundant osmolytes, including proline, polysaccharides, and ectoine. Inoculation with OsiLf-2 increased the osmotic-adjustment ability of the rice host by increasing the proline content (by 250.3% and 49.4%) and soluble sugar (by 20.9% and 49.4%) in rice under drought and salt conditions, relative to the uninoculated control. OsiLf-2 increased stress responses in the rice host at the physiological and biochemical levels (photosynthesis efficiency, osmolytes and antioxidant content), and the gene level (osmolytes synthesis, stress-responsive and ion-transport related genes), raising rice yields under both greenhouse and saline–alkaline soil conditions. The use of endophytic actinomycetes offers a promising biotechnological approach to developing stress-tolerant plants.
