Locus for Malate Secretion in Rice Chromosome 3

Abstract

Aluminum (Al) toxicity is a major limiting factor of rice production in acid soil. One of the tolerance mechanisms of plant to Al stress is the secretion of malate from plant root. The objective of this research is to identifiy quantitative triat loci (QTL) in chromosome 3 that controls malate secretion from rice root during the period of Al stress. The research was conducted in laboratory and green house. An F2 population derived from the cross between rice genotype Hawara Bunar and cultivar lR64 was used in this experiment. Analysis malate secretion was carried out based on enzymatic method. Rice simple sequence repeats from chromosome 3 were as moelcular marker. The mapping and QTL anaysis was performed using Mapmaker 3 and Mapmaker/QTL. The result showed that the malate secretion trait was normally distributed in the rice F2 population indicating that he trait is polygenic trait. A QTL for malate secretion was identified in the short arm of rice chromosome 3 located in between markers RM545 and RM517.