Effects of enhanced UV-B radiation on nitrogen transformation and functional biological properties in the rice rhizosphere. Issue 9 (29th July 2023)

• Record Type: Journal Article
• Authors: Xiao, Huichuan; Wu, Jiong; Zhang, Yanxue; Li, Zuran; Zhan, Fangdong; Li, Yuan; He, Yongmei
• Is Part Of: Archives of agronomy and soil science. Volume 69:Issue 9(2023)
• Page Start: 1645
• Page End: 1659
• Publication Date: 2023-07-29
• Subjects: UV-B radiation -- rice rhizosphere -- nitrogen transformation -- gene expression -- N2O emissions; Horticulture -- Periodicals; Soils -- Periodicals; 630.5
• DOI: 10.1080/03650340.2022.2103675
• Languages: English
• ISSNs: 0365-0340

Abstract

ABSTRACT: To clarify the effect of enhanced UV-B radiation on soil nitrogen transformation and its biological processes in paddy fields, the effects of enhanced ultraviolet-B radiation (0, 2.5, 5.0 and 7.5 kJ m −2 ) on soil nitrogen transformation and N2 O emission, functional microbial quantity, enzyme activity, and gene expression during the growth period (tillering, jointing, booting and maturity stage) of rice were investigated in situ in a rice paddy field in the Yuanyang terraces, Yunnan Province, southwest China. The results show that UV-B radiation decreased the NH4 + -N content, increased the NO3 – N content in the rhizosphere, decreased N2 O emissions from paddy fields, and significantly affected the properties of soil nitrogen transforming microorganisms. The 5.0 kJ m −2 UV-B radiation increased the quantity of ammonifying bacteria and ammonia oxidizing bacteria by 18–160% and 34–151%, respectively, decreased the urease activity in the rice rhizosphere by 11.9–27%; and significantly increased the expression of AOB-amoA and nosZ genes. Thus, the enhanced UV-B radiation increased the ammonia-oxidizing bacteria and AOB-amoA and nosZ gene expression, promoted the transformation of NH4 + -N to NO3 – N in the rice rhizosphere, and reduced N2 O emissions in the paddy field.