Control strategies for rice "straighthead" through physicochemical and biological methods on arsenic transformation and transportation.

Straighthead is a widespread physiological disease affecting rice, characterized by sterile florets and distorted palea and lemma, which can reduce grain yield by up to 100%. In recent decades, arsenic (As) has emerged as a focal point in straighthead research. This paper elucidates the relationship between As toxicity and straighthead while reviewing preventive measures, including water and fertilizer management and the application of resistant cultivars. The optimization of water and fertilizer management enhances the redox potential for As oxidation and/or changes the microbial community involved in As demethylation in rice fields, leading to increased immobility or affinity of As with other minerals. Furthermore, we integrate our previous genetic studies on straighthead with the As metabolism to uncover its genetic foundations. The results indicate that quantitative trait loci (QTL) associated with straighthead co-locate with QTL/genes related to As within the rice genome. These QTL/genes are frequently involved in the phosphate/silicate (Pi/Si) transporter responsible for As uptake. Such co-localizations imply that the Pi/Si transporter facilitates the translocation of As from roots to shoots, thereby contributing to the occurrence of straighthead. Throughout this text, we underscore the preeminence of the genetic strategy as an optimal solution for managing straighthead. The adoption of resistant cultivars effectively tackles the multifaceted challenges related to water management, such as high costs, water resource wastage, and potential yield losses. Additionally, it addresses concerns regarding fertilizer application, which is heavily reliant on soil conditions and poses significant environmental pollution risks.