RNAi-mediated suppression of the abscisic acid catabolism gene Os ABA8ox1 increases abscisic acid content and tolerance to saline–alkaline stress in rice(Oryza sativa L.)  

作　　者：Xiaolong Liu Xianzhi Xie Chongke Zheng Lixing Wei Xiaowei Li Yangyang Jin Guohui Zhang Chang-Jie Jiang Zhengwei Liang 

机构地区：[1]Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,Jilin,China [2]Shandong Rice Research Institute,Shandong Academy of Agricultural Sciences,Jinan 250100,Shandong,China [3]College of Life Science and Resources and Environment,Yichun University,Yichun 336000,Jiangxi,China [4]Da’an Sodic Land Experiment Station,Da’an 131317,Jilin,China [5]Dongying Academy of Agricultural Sciences,Dongying 257091,Shandong,China [6]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 [7]Institute of Agrobiological Sciences,NARO,Kannondai 2-1-2,Tsukuba 305-8602,Japan

出　　处：《The Crop Journal》2022年第2期354-367,共14页作物学报（英文版）

基　　金：supported by National Key Research and Development Program of China(SQ2018YFD020224);Chinese Academy of Sciences STS Network Foundation(KFJ-SW-STS-141-01);the Strategic Priority Research Program of Chinese Academy of Sciences(XDA080X0X0X);the Foundation of Innovation team International Partner Program of Chinese Academy of Sciences(KZZD-EW-TZ-07-08)。

摘　　要：Saline–alkaline(SA) stress is characterized by high salinity and high alkalinity(high p H), 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 Os ABA8 ox1(Os ABA8 ox1-kd), a key ABA catabolic gene, significantly increased tolerance to SA stress in rice plants. We produced Os ABA8 ox1-kd lines in two different japonica cultivars, Dongdao 4 and Nipponbare. Compared with nontransgenic control plants(WT), the Os ABA8 ox1-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 Na;CO;. In pot trials using SA field soils of different alkali levels(p H 7.59, 8.86, and 9.29), Os ABA8 ox1–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(p H = 9.29, EC = 834.4 μS cm-1),Os ABA8 ox1-kd lines showed an 194.5%–1090.8% increase in grain yield per plant relative to WT plants.These results suggest that suppression of Os ABA8 ox1 to increase endogenous ABA levels provides a new molecular approach for improving rice yield in SA paddies.

关 键 词：Rice(Oryza sativa L.) Saline–alkaline stress Abscisic acid(ABA) OsABA8ox1-kd Endogenous ABA levels 

分 类 号：S511[农业科学—作物学]