Project description:Germination of seeds of Orobanche species requires specific chemicals exuded by host roots. A family of “divergent” KARRIKIN INSENSITIVE2 (KAI2d) genes encode proteins that recognize strigolactone (SL) class germination simulants. We explored specificity of germination stimulant detection by analyzing interspecific segregants of a cross between Orobanche cernua and O. cumana, closely related species that differ in stimulant response. O. cernua parasitizes tomato and germinates in response to the SL orobanchol, while O. cumana parasitizes sunflower and responds to dehydrocostus lactone (DCL). KAI2d genes were catalogued in parents and in segregants that showed stimulant specificity. KAI2d genes were also functionally assayed in the Arabidopsis kai2 mutant background. We identified five full-length KAI2d genes in O. cernua and eight in O. cumana. The O. cernua KAI2d2, as well as its ortholog in O. cumana, are associated with SL perception. A cluster of O. cumana KAI2d genes was genetically linked to DCL perception, although no specific receptor gene was identified by heterologous complementation. These findings support the KAI2d-mediated perception of SLs, but fall short of explaining how O. cumana perceives DCL. The ability of some O. cumana KAI2d genes to detect SLs points to the involvement of additional factors in regulating stimulant specificity.
2022-02-20 | GSE196954 | GEO
Project description:Biological and transcriptomic characterization of resistance to sunflower broomrape (Orobanche cumana W.) in sunflower (Helianthus annuus L.)
Project description:affy_mildew_sunflower - A quantitative resistance of sunflower to downy mildew (Plasmopara halstedii) has been mapped on LG10 (Vear et al., 2008). Is this quantitative resistance involving novel biological mechanisms? Compare the pattern of expression of specific resistances harboured by the Pl5/Pl2 alleles and the quantitative resistance harboured by the favourable allele at the mapped QTL, during compatible and incompatible interactions in the pathosystem Helianthus annuus / Plasmopara halstedii 60 arrays - SUNFLOWER; normal vs disease comparison
Project description:affy_mildew_sunflower - A quantitative resistance of sunflower to downy mildew (Plasmopara halstedii) has been mapped on LG10 (Vear et al., 2008). Is this quantitative resistance involving novel biological mechanisms? Compare the pattern of expression of specific resistances harboured by the Pl5/Pl2 alleles and the quantitative resistance harboured by the favourable allele at the mapped QTL, during compatible and incompatible interactions in the pathosystem Helianthus annuus / Plasmopara halstedii
