Enhanced Rice Resistance to Sheath Blight through Nitrate Transporter 1.1B Mutation without Yield Loss under NH4 + Fertilization

• Published in: Journal of agricultural and food chemistry Vol. 71; no. 50; pp. 19958 - 19969
• Main Authors: Li, Dandan, Wu, Xianxin, Huang, Chunyan, Lin, Qiujun, Wang, Yan, Yang, Xu, Wang, Chuang, Xuan, Yuanhu, Wei, Songhong, Mei, Qiong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 20.12.2023
• Subjects: Agricultural and Environmental Chemistry; sheath blight; NH4 + fertilizer; rice; resistance; Nitrate transporter 1.1B
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.3c05350

Nitrogen fertilization can promote rice yield but decrease resistance to sheath blight (ShB). In this study, the nitrate transporter 1.1b (nrt1.1b) mutant that exhibited less susceptibility to ShB but without compromising yield under NH4 + fertilization was screened. NRT1.1B’s regulation of ShB resistance was independent of the total nitrogen concentration in rice under NH4 + conditions. In nrt1.1b mutant plants, the NH4 + application modulated auxin signaling, chlorophyll content, and phosphate signaling to promote ShB resistance. Furthermore, the findings indicated that NRT1.1B negatively regulated ShB resistance by positively modulating the expression of H+-ATPase gene OSA3 and phosphate transport gene PT8. The mutation of OSA3 and PT8 promoted ShB resistance by increasing the apoplastic pH in rice. Our study identified the ShB resistance mutant nrt1.1b, which maintained normal nitrogen use efficiency without compromising yield.