Wheat Sharp Eyespot Resistance Evaluation Of Wheat-psathyrostachys Huashanica Derived Lines And Development Of Ns Chromosome Specific SCAR Markers

Psathyrostachys huashanica is one of the most significant wild relatives of wheat.It has many good traits such as disease-resistance and stress resistance,makes it become a fine gene resource of distant hybridization.In this study,53 common wheat and wheat-psathyrostachys huashanica derivative line materials were tesed to identify the resistance to wheat sharp eyespot by means of artificial sharp eyespot inoculation,combined with morphologic observation and cytological detecion to screen out the disease-resistant material;RAPD markers were screened in a complete set of wheat-psathyrostachys huashanica disomic addition lines,to develop psathyrostachys huashanica Ns chromosome specific SCAR markers.Main results of the experiment are as follows,1.Wheat-psathyrostachys huashanica derivative line materials wheat sharp eyespot resistance assessment and cytology identification.51 wheat-psathyrostachys huashanica derivative line materials used as test group,2 common wheat varieties 7182 and Yangmai 158 were used as high susceptible cultivars control set.Artificial evaluation for resistance to wheat sharp eyespot of 53 wheat materials showed that sharp eyespot resistance among different materials are varied,average disease index value range from 20.0% to 82.0%.11 materials were identified as disease resistance level(R),account for 21.6% of the total number of materials.Disease index value by an average of 26.8%.27 materials were identified as moderately resistance level(MR),with an average disease index value of 46.9%,account for 52.9% of the total.13 materials were identified as lower than moderately susceptible level(MS),with an average disease index value of 61.9%,account for 25.5% of the total.Cytogenetic analysis and genomic in situ hybridization(GISH)were conducted in 11 disease resistance materials.All 11 materials have 42 chromosomes in root tip cells,and no positive signals were perceived in GISH.Due to the significant difference among the test materials and parental material 7182 in disease resistance trait and other agronomic traits,conclude these 11 materials are wheat-P.huashanica small fragment chromosome translocation lines.2.Development of Ns chromosome specific SCAR markers.of Psathyrostachys huashanica.180 RAPD primers were screend in 8 wheat-P.huashanica disomic addition lines and parental material 7182.5 RAPD primers have specific PCR amplification in P.huashanica chromosomes 1Ns,2Ns,4Ns and 5Ns respectively.Specific fragments were purificated from gel and cloned for sequencing.5 SCAR markers were designed based on fragments sequence and verified in 9 wheat materials.One of the markers S2Ns-131 can only amplified the specific bands on Psathyrostachys huashanica and wheat-P.huashanica 2Ns disomic addition line,and no bands were amplified in parental material 7182.Proved that SCAR marker S2Ns-131 could be used as specific marker to detect 2Ns chromosome of Psathyrostachys huashanica.