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Sclerotinia stem rot, caused by fungus Sclerotinia sclerotiorum, is one of the most devastating diseases of rapeseed (Brassica napus L.) in China.The two major factors in limiting developing disease resistance are (1) the absence of accessions with complete resistance and (2) the lack of a single method that can be solely used to assess the resistance (i.e tolerance).However accessions with differential tolerance to S.sclerotiorum have been identified in China.In the present study, one DH population consisting of 72 lines, derived from the F1 generation of a cross between a partially resistant line (DH821) and a susceptible line (DHBao604), was used to identify quantitative trait loci (QTL) involved in the resistance to S.sclerotiorum.Three inoculation methods: mycelial toothpick inoculation (MTI), mycelial plug inoculation (MPI) and infected petal inoculation (IPI) were employed for the assessment of resistance to stem inoculation at the adult plant stage in vivo.A total of 252 molecular markers including 91 SSRs, 72 RAPDs, 86 SRAPs, 2 RFLPs and one EST were used to construct a genetic linkage map with 20 linkage groups covering 1,746.5 cM with an average space of 6.93cM.Composite interval mapping identified ten, one and ten QTL for MTI, MPI and IPI, respectively, at a LOD > 2.5.There was one QTL detected in linkage group N12 by mycelial toothpick inoculation method in 2004 and 2005 and by petiole inoculation method in 2005.One QTL was detected in linkage group N3 and N4 by MPI in 2006 and 2007.There was one common QTL detected by MTI in 2005 and by MPI in 2006.The results provided information about the genetic control of the resistance to S.sclerotiorum in oilseed rape.