Skip to main content
SLU publication database (SLUpub)

Research article2020Peer reviewed

Yield reduction of direct-seeded rice under returned straw can be mitigated by appropriate water management improving soil phosphorus availability

Yang, Haishui; Feng, Jinxia; Weih, Martin; Meng, Yi; Li, Yifan; Zhai, Silong; Zhang, Wuyi

Abstract

The yield of direct-seeded rice has been shown to decrease after straw amendment. However, the reasons for the yield decrease, and any measures to alleviate it, are currently unknown. We hypothesised that straw return exerts negative effects on soil fertility and on root growth of direct-seeded rice, which subsequently reduces the remobilisation of reserves to grains under continuous flooding (CF); and that alternate wetting and drying (AWD) irrigation can alleviate these negative impacts. Field and greenhouse experiments were conducted to test the hypotheses, by comparing CF and AWD in combination with two wheat-straw treatments (incorporation and mulching). Under CF, wheat-straw incorporation decreased soil available phosphorus by 23-79%, root biomass by 10%, leaf biomass by 13%, and leaf area by 15% compared with the control with no straw incorporation; negative effects on these characteristics were lessened if the straw was mulched. The AWD treatment alleviated the negative effects of straw incorporation compared with CF, and straw mulching with AWD had no negative effects or resulted in positive effects. The results suggest that CF along with straw incorporation limits soil phosphorus availability, root growth and grain yield by affecting photosynthate accumulation and remobilisation. AWD irrigation mitigates these undesirable effects by decreasing soil total reductants, which subsequently increases soil pH and plant-available phosphorus. The proposed AWD treatment could be a promising strategy for the sustainable production of direct-seeded rice.

Keywords

phosphorus immobilization; rice-wheat rotation system; straw management; yield formation

Published in

Crop & Pasture Science
2020, Volume: 71, number: 2, pages: 134-146
Publisher: CSIRO PUBLISHING

    Sustainable Development Goals

    SDG2 End hunger, achieve food security and improved nutrition and promote sustainable agriculture
    SDG12 Ensure sustainable consumption and production patterns

    UKÄ Subject classification

    Agricultural Science

    Publication identifier

    DOI: https://doi.org/10.1071/CP19396

    Permanent link to this page (URI)

    https://res.slu.se/id/publ/104951