RNAi-mediated suppression of the abscisic acid catabolism gene OsABA8ox1 increases abscisic acid content and tolerance to saline–alkaline stress in rice (Oryza sativa L.)

Crop Journal

Xianzhi Xie¹  Chang-Jie Jiang²  Yangyang Jin³  Xiaowei Li⁴  Guohui Zhang⁵  Xiaolong Liu⁵  Zhengwei Liang⁵  Chongke Zheng⁶  Lixing Wei⁶ 

[1] College of Life Science and Resources and Environment, Yichun University, Yichun 336000, Jiangxi, China;Da’an Sodic Land Experiment Station, Da’an 131317, Jilin, China;College of Life Sciences, Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, Jilin Agricultural University, Changchun 130118, Jilin, China;Dongying Academy of Agricultural Sciences, Dongying 257091, Shandong, China;Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China;Shandong Rice Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, Shandong, China;

关键词: Rice (Oryza sativa L.);    Saline–alkaline stress;    Abscisic acid (ABA);    OsABA8ox1-kd;    Endogenous ABA levels;   

DOI  :  

来源: DOAJ

【 摘 要 】

Saline–alkaline (SA) stress is characterized by high salinity and high alkalinity (high pH), which severely inhibit plant growth and cause huge losses in crop yields worldwide. Here we show that a moderate elevation of endogenous abscisic acid (ABA) levels by RNAi-mediated suppression of OsABA8ox1 (OsABA8ox1-kd), a key ABA catabolic gene, significantly increased tolerance to SA stress in rice plants. We produced OsABA8ox1-kd lines in two different japonica cultivars, Dongdao 4 and Nipponbare. Compared with non-transgenic control plants (WT), the OsABA8ox1-kd seedlings accumulated 25.9%–55.7% higher levels of endogenous ABA and exhibited reduced plasmalemma injury, ROS accumulation and Na+/K+ ratio, and higher survival rates, under hydroponic alkaline conditions simulated by 10, 15, and 20 mmol L−1 of Na2CO3. In pot trials using SA field soils of different alkali levels (pH 7.59, 8.86, and 9.29), OsABA8ox1–kd plants showed markedly higher seedling survival rates and more vigorous plant growth, resulting in significantly higher yield components including panicle number (85.7%–128.6%), spikelets per panicle (36.9%–61.9%), branches (153.9%–236.7%), 1000–kernel weight (20.0%–28.6%), and percentage of filled spikelets (96.6%–1340.8%) at harvest time. Under severe SA soil conditions (pH = 9.29, EC = 834.4 μS cm−1), OsABA8ox1-kd lines showed an 194.5%–1090.8% increase in grain yield per plant relative to WT plants. These results suggest that suppression of OsABA8ox1 to increase endogenous ABA levels provides a new molecular approach for improving rice yield in SA paddies.

【 授权许可】

Unknown