Reference "Candidate defense genes from rice, barley, and maize and their association with qualitative and quantitative resistance in rice"

Reference ID

7755

Title

Candidate defense genes from rice, barley, and maize and their association with qualitative and quantitative resistance in rice

Source

Molecular plant-microbe interactions : MPMI, 2003, vol. 16, pp. 14-24

Authors (11)

Ramalingam-J	Kukreja-K	Chittoor-J-M	Wu-J-L
Lee-S-W	Baraoidan-M	George-M-L	Cohen-M-B
Hulbert-S-H	Leach-J-E	Leung-H

Abstract

Candidate genes involved in both recognition (resistance gene analogs [RGAs])
and general plant defense (putative defense response [DR]) were used as
molecular markers to test for association with resistance in rice to blast,
bacterial blight (BB), sheath blight, and brown plant-hopper (BPH). The 118
marker loci were either polymerase chain reaction-based RGA markers or
restriction fragment length polymorphism (RFLP) markers that included RGAs or
putative DR genes from rice, barley, and maize. The markers were placed on an
existing RFLP map generated from a mapping population of 116 doubled haploid
(DH) lines derived from a cross between an improved indica rice cultivar, IR64,
and a traditional japonica cultivar, Azucena. Most of the RGAs and DR genes
detected a single locus with variable copy number and mapped on different
chromosomes. Clusters of RGAs were observed, most notably on chromosome 11 where
many known blast and BB resistance genes and quantitative trait loci (QTL) for
blast, BB, sheath blight, and BPH were located. Major resistance genes and QTL
for blast and BB resistance located on different chromosomes were associated
with several candidate genes. Six putative QTL for BB were located on
chromosomes 2, 3, 5, 7, and 8 and nine QTL for BPH resistance were located to
chromosomes 3, 4, 6, 11, and 12. The alleles of QTL for BPH resistance were
mostly from IR64 and each explained between 11.3 and 20.6% of the phenotypic
variance. The alleles for BB resistance were only from the Azucena parent and
each explained at least 8.4% of the variation. Several candidate RGA and DR gene
markers were associated with QTL from the pathogens and pest. Several RGAs were
mapped to BB QTL. Dihydrofolate reductase thymidylate synthase co-localized with
two BPH QTL associated with plant response to feeding and also to blast QTL.
Blast QTL also were associated with aldose reductase, oxalate oxidase, JAMyb (a
jasmonic acid-induced Myb transcription factor), and peroxidase markers. The
frame map provides reference points to select candidate genes for cosegregation
analysis using other mapping populations, isogenic lines, and mutants.