Establishment of Cytogenetic Marker for Aegilops searsii

Ding Hongke; Gong Wenping; Ni Jiajun; Wang Kai; Cui Fa; Liu Jianjun; Liu Cheng

doi:10.14083/j.issn.1001-4942.2025.05.007

Abstract：Aegilops searsii,a related plant of wheat,has excellent resistance to abiotic and biotic stres-ses,which is an excellent gene source for wheat improvement.Fluorescence in situ hybridization(FISH)is a powerful cytogenetic tool for detecting the chromosomes of some related plants of wheat.In order to verify its feasibility to identify the chromosomes of A.searii in wheat background,the FISH analysis of the Chinese Spring-A.searsii 1Ss to 7Ss addition lines was performed with Oligo-pSc119.2-1,Oligo-pTa535-1 and(GAA)8 as probes,and using Chinese Spring as control.The results of double-color FISH with Oligo-pSc119.2-1 and Oligo-pTa535-1 as probes showed that Oligo-pSc119.2-1 had hybridization signals at ends or proximal ends of the long and short arms of chromosomes in A.searii 1Ss to 7Ss,whereas Oligo-pTa535-1 had relatively weak hybridization signals only at near middle of 3Ss L and near terminal of 7Ss S.The result of FISH using(GAA)8 as probe showed that the hybridization signal was present in different positions on chromosomes 1Ss to 7Ss.At the same time,the ratio of long arm to short arm of each chromosome in A.searsii was analyzed and the results showed that the ratio of 1Ss to 7Ss chromosomes were different,among which,1Ss to 5Ss were subcentral cen-tromere chromosomes,and 6Ss and 7Ss were central centromere chromosomes.Therefore,combined with chro-mosome arm ratio,the FISH hybridization signal of Oligo-pSc119.2-1 or(GAA)8 could not only accurately distinguish each chromosome of A.searsii,but also be used as cytogenetic marker to identify the chromosome of A.searsii in wheat background.