Molecular Breeding for Iron Toxicity Tolerance in Rice ( Oryza sativa L.)

Abstract

Rice consumption is on an upward trajectory worldwide based on changes in eating habits, population growth, and ease of cooking and yet rice production is not keeping up. There are many constraints including abiotic stresses that significantly reduce rice yields and hence lower rice production. Iron (Fe) toxicity is one of the abiotic stresses that affect lowland rice ecology, mostly under poorly drained field conditions. Excessive iron uptake can lead to complete crop failure if the planted variety is highly sensitive. Fortunately, sources of Fe toxicity tolerance have been reported in both cultivated and wild rice and breeding efforts have resulted in improved rice varieties that are tolerant to this stress. Genetic mapping has led to the identification of several quantitative trait loci (QTL) associated with iron toxicity tolerance. However, understanding the molecular mechanism for tolerance to Fe toxicity is limited. This chapter will cover key achievements in breeding for Fe toxicity tolerance in rice with a key focus on molecular breeding.