Reference "Characterizing rice lesion mimic mutants and identifying a mutant with broad-spectrum resistance to rice blast and bacterial blight"

Reference ID

5157

Title

Characterizing rice lesion mimic mutants and identifying a mutant with broad-spectrum resistance to rice blast and bacterial blight

Source

Molecular plant-microbe interactions : MPMI, 2000, vol. 13, pp. 869-876

Authors (7)

Yin-Z	Chen-J
Zeng-L	Goh-M
Leung-H	Khush-G-S
Wang-G-L

Abstract

Many plant mutants develop spontaneous lesions that resemble disease symptoms in
the absence of pathogen attack. In several pathosystems, lesion mimic mutations
have been shown to be involved in programmed cell death, which in some instances
leads to enhanced disease resistance to multiple pathogens. We investigated the
relationship between spontaneous cell death and disease resistance in rice with
nine mutants with a range of lesion mimic phenotypes. All nine mutations are
controlled by recessive genes and some of these mutants have stunted growth and
other abnormal characteristics. The lesion mimics that appeared on the leaves of
these mutants were caused by cell death as measured by trypan blue staining.
Activation of six defense-related genes was observed in most of the mutants when
the mimic lesions developed. Four mutants exhibited significant enhanced
resistance to rice blast. One of the mutants, spl11, confers non-race-specific
resistance not only to blast but also to bacterial blight. The level of
resistance in the spl11 mutant to the two pathogens correlates with the defense-
related gene expression and lesion development on the leaves. The results
suggest that some lesion mimic mutations in rice may be involved in disease
resistance, and cloning of these genes may provide a clue to developing broad-
spectrum resistance to diverse pathogens.