Development And Molecular Cytogenetic Identification Of Spontaneous Chromosome Structural Aberrations Between Common Wheat And Thinopyrum Bessarabicum

Thinopyrum bessarabicum(2n = 2x = 14,JJ or EbEb)is an important genetic resource for wheat improvement.In our previous study,several spontaneous translocations have been identified from hybrids of wheat Chinese Spring(CS)and CS-Thinopyrum bessarabicum amphiploid.Molecular markers play important roles in chromosome engineering.In this study,transferability of rye EST markers derived from transcriptome sequences was identified,new markers specific for Thinopyrum bessarabicum were developed and used for chromosome mapping and marker-aided selection of wheat-Thinopyrum bessarabicum spontaneous translocations occurred in hybrids of CS and CS-Thinopyrum bessarabicum amphiploid.The major results were as following.Amplified in rye,CS,Thinopyrum bessarabicum and CS-Thinopyrum bessarabicum amphiploid,of 277 pairs of rye transcriptome-derived primers,223(80.5%)produced amplicons in Thinopyrum bessarabicum,and 40 Thinopyrum bessarabicum specific markers derived from 25 primer pairs were identified.Using 8 CS-Thinopyrum bessarabicum alien chromosome lines involving 7 chromosomes of Thinopyrum bessarabicum,14 markers were mapped to chromosome 1 J(2),2J(3),4J(3),5J(3),6J(2)and 7J(1),3 were mapped in more than two chromosomes,the other 23 remained no mapping information in the current lines.Marker aided selection and cytogenetic analysis identified 24 wheat alien lines from hybrids F9-F11 of CS and CS-Thinopyrum bessarabicum amphiploid,which involved 6 additions,13 small segmental translocations,2 telosomes and 3 complex variations.19 alien lines were characterized based on the analysis of the 40 current and 19 previous markers,17 contained some of these markers,which involved chromosomes 1JS,2JS,4JS,5J,6JS and 7JS,while the other two did not carry any of these markers,indicating new kind of telosome or small segmental tranlocations.Phenotypic analysis of 28 CS-Thinopyrum bessarabicum alien chromosome lines found that plant height,spike length and spikelets per spike varied much.Of them,the plant height varied from 69～162 cm,spike length varied from 4～15 cm and spikelets per spike varied from 11～27.Lines added chromosomes 5J showed reduced plant height.Except above traits,the other traits of these lines showed no obvious changes in comparison with their wheat parent Chinese Spring.