CROP PRODUCTION AND ENVIRONMENT DIVISION: Physiological mechanisms of aluminum resistance of rice varieties and the development of a rapid screening method for resistant genotypes

摘要

Upland rice is an important crop for small farmers in developing countries. The growth of upland rice is often reduced by the soil acidity of highly weathered soils (Oxisols and Ultisols) that are widely distributed in tropical regions. Since many farmers cannot apply high levels of lime to correct soil pH due to economic constraints, the development of genotypes resistant to soil acidity is necessitated. Few studies have been conducted for the acid-soil resistance of upland rice compared to those ofother crops such as wheat. A previous study conducted by JIRCAS in the savannas of South America revealed that calcium (Ca) plays a major role in the genotypic differences of upland rice that are responsible for resistance to soil acidity in Oxisols. In this study, the mechanisms of resistance to acid soils in rice was elucidated in relation to Ca in comparison to cases of wheat, and a new efficient screening method was proposed.