Molecular Cytogenetic Identification Of Tow Wheat-Leymus Mollis Addition Lines

Leymus mollis?Trin.?Hara,2n=4x=28,NsNsXmXm)is a perennial heterogeneity of the Triticeae family?Hordinae?Leymus Hochst.The tetraploid wild plant has excellent traits such as large ears and many flowers,thick and strong stems,and immunity to various fungal diseases.It is an important tertiary gene source for wheat genetic improvement.Through chromosomal engineering,the excellent genes of Hamai can be transferred into the common wheat background to enrich wheat germplasm resources,broaden the genetic basis of wheat,and increase the diversity of wheat breeding parents.This study comprehensively used cytology,in situ hybridization,molecular marker technology,agronomic traits investigation and stripe rust resistance identification for common wheat-Baimai-derived offspring M11005-1-2-7-10-1-1?M11005A?,M13058A?M13058-1-3-2-1 and M13058-1-3-2-2?were identified as follows:?1?Molecular genetic identification of wheat-Leymus mollis disomic addition line M11005ALeymus mollis is a tertiary gene source for wheat with many excellent traits to improve wheat.M11005-1-2-7-10-1-1?M11005A?is F₆ selected from common wheat cultivar 7182and wheat-L.mollis derived line M42?2n=54?.Cytological observations showed that M11005A has 44 chromosomes with good pairing and it has stable inheritance.In situ hybridization and molecular markers results showed that M11005A contained 42common wheat chromosomes and 1 pair of chromosomes from L.mollis Lm#3Ns,and Lm#3Ns FISH karyotype was obtained by Oligo-pTa535 probe.Screening 6 ESTs and 8 PLUG-specific molecular markers can be used to identify Lm#3Ns chromosomes.Only one EST and four PLUG markers can amplify the bands of L.mollis andPsathyrostachys huashanica in M11005A simultaneously.This indicated that there is a certain difference between the Lm#3Ns chromosome of L.mollis and P.huashanica.M11005A had no significant difference in morphology,such asspikelength,panicle type,spikelets and 1000-grain weight,but the number oftillers was significantly higher than 7182,and the plant height was significantly decreased.The results of stripe rust resistance identification showed that M11005A had high resistance to CYR29 and CYR34,and also high sensitivity to CYR32,but it had high resistance to CYR32 and CYR33 mixed races at the adult stage.It is speculated that the Lm#3Ns chromosome of L.mollis carrying genes which resistant to CYR29 and CYR34,and also genes against CYR32 and CYR33 mixed races in the adult stage are also included.Therefore,M11005A is a wheat-L.mollis disomic addition line,it can be used as a resistant source in the improvement of stripe rust resistance of wheat.?2?Molecular genetic identification of wheat-Leymus mollis double telosome addition line M13058AThe karyotype analysis showed that the karyotype of M13058A was 2n=21.62II+0.28I+0.1IV,and the whole genome DNA of L.mollis,In situ hybridization and molecular marker results indicate that M13058A was attached with a pair of short arm of L.mollis 1Ns chromosome,temporarily named as DT1NsS,and the 1B chromosomeof M13058A is derived from the parental Zhoumai 24,and the 5B chromosome is derived from the parental7182.There is a little difference in the agronomic traits such as plant height,plant type,tillers,panicle length,panicle type,and 1000-grain weight,but it is basically different from Zhoumai 24.In terms of stripe rust,M13058A showed high resistance to CYR29,CYR32,CYR34 races and the mixed races of CYR32 and CYR32,indicating that the resistance genes of these races were carried on the short arm chromosome of Lm#1Ns.M13058A has a wide range of resistance to stripe rust races,which has improved the resistance of Zhoumai24 to stripe rust and has little effect on other agronomic traits.Therefore,M13058A is a wheat-L.mollis DT1NsS double-telosome addition system,which is a great inheritance in the improvement of stripe rust resistance.