Characterization, identification and evaluation of a set of wheat-Aegilops comosa chromosome lines

Abstract

This study characterized and evaluated a set of wheat-Aegilops comosa introgression lines, including six additions and one substitution. A total of 47 PLUG markers and a set of cytogenetic markers specific for Ae. comosa chromosomes were established after screening 526 PLUG primer pairs and performing FISH using oligonucleotides as probes. Marker analysis confirmed that these lines were wheat-Ae. comosa 2M–7M addition lines and a 6M(6A) substitution line. The molecular and cytogenetic markers developed herein could be used to trace Ae. comosa chromatin in wheat background. In order to evaluate the breeding value of the material, disease resistance tests and agronomical trait investigations were carried out on these alien chromosome introgression lines. Disease resistance tests showed that chromosomes 2M and 7M of Ae. comosa might harbor new stripe rust and powdery mildew resistance genes, respectively, therefore, they could be used as resistance sources for wheat breeding. Investigations into agronomical traits showed that all chromosomes 2M to 7M had detrimental effects on the agronomic performance of wheat, therefore, the selection of plants with relatively negative effects should be avoided when inducing wheat-A. comosa chromosome translocations using chromosome engineering procedures.

Analysis of Structural Genomic Diversity in Aegilops umbellulata, Ae. markgrafii, Ae. comosa, and Ae. uniaristata by Fluorescence In Situ Hybridization Karyotyping

“…Six probes, namely oligo-pSc119.2, oligo-pTa71, oligo-pTa713, (AAC) 5 , (CTT) 12 , and (ACT) 7 , which are suited for use in identifying the chromosomes of common wheat and Aegilops species (Cuadrado and Jouve, 2010;Tang et al, 2014;Zhao et al, 2016) were used in the current investigation. The chromosomes of the four diploid Aegilops species were identified and classified based on the FISH patterns of these DNA probes combined with the C-banding karyotypes in previous investigations (Friebe et al, 1995(Friebe et al, , 1996aBadaeva et al, 1996a;Danilova et al, 2017;Liu et al, 2019;Song et al, 2019). The 5 -ends of oligo-pSc119.2 and oligo-pTa71 were labeled with 6-carboxyfluorescein (6-FAM), and the remaining four probes were labeled with 6carboxy tetramethylrhodamine (Tamra).…”

“…In addition to the evolutionary contribution to polyploid Aegilops species, the diploid Aegilops species including those with U, M, C, and N genomes also harbor abundant beneficial genes for the genetic improvement of bread wheat with respect to, for instance, resistance to leaf and stripe rust (Sears, 1956;Riley et al, 1968;Riar et al, 2012;Toor et al, 2016;Bansal et al, 2017;Liu et al, 2019) and powdery mildew (Gill et al, 1985;Zhu et al, 2006;Weidner et al, 2012), tolerance to salt (Gorham, 1990) and aluminum stress (Miller et al, 1995), accumulation of zinc and iron (Wang et al, 2011;Neelam et al, 2012), high efficiency in zinc uptake (Cakmak et al, 1999), as well as high protein content and gluten content (Gong et al, 2017;Wang et al, 2017).…”

“…comosa, and Ae. uniaristata, and their introgression lines with wheat (Badaeva et al, 1996a(Badaeva et al, , 2011Iqbal et al, 2000;Molnár et al, 2011Molnár et al, , 2015Molnár et al, , 2016Kwiatek et al, 2013;Mirzaghaderi et al, 2014;Danilova et al, 2017;Liu et al, 2019;Song et al, 2019).…”

Identification and Characterization of Wheat - Aegilops Comosa 7M/7A Disomic Substitution Lines with Stripe Rust Resistance

“…comosa amphidiploids and chromosome introgression lines, such as addition, substitution, and translocation lines, are the rst step for transferring desirable genes from Ae. comosa to common wheat (Liu et al 2019). Several wheat -Ae.…”

“…Of these introgression lines, the 2M and 7M chromosomes of Ae. comosa were found to carry genes for resistance to stripe rust (Riley et al 1968) and powdery mildew (Liu et al 2019), respectively. Aegilops geniculata Roth is an annual self-fertilizing tetraploid species (2n = 4x = 28) with genomic formula U g U g M g M g , where the M g genome originated from Ae.…”