In vitro plant extract test for screening relative resistance of wheat cultivars against Mycosphaerella graminicola

Abstract

Septoria tritici blotch (STB) caused by Mycosphaerella graminicola, is one of the most devastating disease of wheat worldwide. Due to time and rate of defense genes expression, cultivar reaction to disease is different. So time and rate of defense genes expression can lead to develop an in vitro test for screening relative resistance of cultivars against pathogen. Forty wheat genotypes were screened by artificial infection and Marvdasht and Chamran as a resistant and Darab2 and Tajan as a susceptible cultivar were selected. Two treatments including scratched and not scratched leaves were considered for each cultivar. The soluble components were extracted 24 and 48 h after scratching the leaves and effect of extracts on sporulation and germination of M.graminicola spores was investigated. Increment of spore population in resistant cultivars was lower than susceptible ones. Also germination percent on media with resistant cultivars extract was lower as compared with media with extracts of very susceptible cultivars extract. The cDNA-AFLP experiment showed that expression of peroxidase 3 and 8 genes was increased in Chamran and Marvdasht cultivars respectively 48 hour after scratching the leaves. So it seems that we can use in vitro plant extract for screening relative resistance of wheat cultivars against M.graminicola.

Keywords

• leaf extract of resistant and sensitive wheat cultivar
• spore population
• septoria
• cdna-aflp
• defense genes