New wheat-rye 5DS-4RS·4RL and 4RS-5DS·5DL translocation lines with powdery mildew resistance

Abstract

Powdery mildew is one of the serious diseases of wheat (Triticum aestivum L., 2 n = 6 × = 42, genomes AABBDD). Rye (Secale cereale L., 2 n = 2 × = 14, genome RR) offers a rich reservoir of powdery mildew resistant genes for wheat breeding program. However, extensive use of these resistant genes may render them susceptible to new pathogen races because of co-evolution of host and pathogen. Therefore, the continuous exploration of new powdery mildew resistant genes is important to wheat breeding program. In the present study, we identified several wheat-rye addition lines from the progeny of T. aestivum L. Mianyang11 × S. cereale L. Kustro, i.e., monosomic addition lines of the rye chromosomes 4R and 6R; a disomic addition line of 6R; and monotelosomic or ditelosomic addition lines of the long arms of rye chromosomes 4R (4 RL) and 6R (6 RL). All these lines displayed immunity to powdery mildew. Thus, we concluded that both the 4 RL and 6 RL arms of Kustro contain powdery mildew resistant genes. It is the first time to discover that 4 RL arm carries powdery mildew resistant gene. Additionally, wheat lines containing new wheat-rye translocation chromosomes were also obtained: these lines retained a short arm of wheat chromosome 5D (5 DS) on which rye chromosome 4R was fused through the short arm 4 RS (designated 5 DS-4 RS · 4 RL; 4 RL stands for the long arm of rye chromosome 4R); or they had an extra short arm of rye chromosome 4R (4 RS) that was attached to the short arm of wheat chromosome 5D (5 DS) (designated 4 RS-5 DS · 5 DL; 5 DL stands for the long arm of wheat chromosome 5D). These two translocation chromosomes could be transmitted to next generation stably, and the wheat lines containing 5 DS-4 RS · 4 RL chromosome also displayed immunity to powdery mildew. The materials obtained in this study can be used for wheat powdery mildew resistant breeding program.

A systematic review of rye (Secale cereale L.) as a source of resistance to pathogens and pests in wheat (Triticum aestivum L.)

“…striiformis Puccinia graminis f. sp. tritici Blumeria graminis ND4BL.4RL + 7AS.4RSGerman white rye; WR41-1 [86] Pm20 6BS.6RLProlific rye; WGRC28 [65]ND5DS-4RS.4RLKustro rye and MK25 triticale [87]ND6RLKustro rye and triticale MK25 [87]ND6RGerman white rye; WR49-1 [88] Schizaphis graminum Diurarphis noxia Rhopalosiphum padi Sitobion avenae Mayetiola destructor H25 4BS.4BL-6RLBalbo rye; 88HF16 wheat [65, 89] Aceria tosichell Heterodera avenae CreR 6DS.6RLT-701 triticale derives [90] Heterodera filipjevi ND(6D) 6R[91] a Gene designations according to McIntosh et al [26] unless: b additional with temporary designation or ND no designation …”

Production and Identification of Wheat-Agropyron cristatum 2P Translocation Lines

“…To date, approximately 42 loci with more than 70 alleles conferring resistance to powdery mildew genes [ 66 ] and more than 70 loci for leaf rust resistance genes [ 67 ] have been reported. Unfortunately, many of these resistance genes usually become ineffective when new pathogen variants emerge due to co-evolution of the host and pathogen [ 68 ]. Hence, there is an urgent need to identify new and effective sources of resistance for wheat improvement.…”

Physical Location of New PCR-Based Markers and Powdery Mildew Resistance Gene(s) on Rye (Secale cereale L.) Chromosome 4 Using 4R Dissection Lines

“…Some of the MK seeds were irradiated with fast neutrons at the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, China. The irradiated MK seeds were used as recipients to cross with common wheat T. aestivum L. Chuannong 27 (CN27), and line 12FT2115 was selected from the progeny of this cross combination ( Fu et al, 2014 ). Some of the selfed progeny (seeds) of lines 12FT2115 and MTA4RL Ku were irradiated with 60 Co-γ rays at the Biotechnology and Nuclear Technology Research Institute, Sichuan Academy of Agricultural Sciences, China.…”

“…New powdery mildew resistance gene(s), which differ from previously reported rye genes, were located on 4R chromosome of rye cultivar German White ( An et al, 2013 ). It has been reported that the 4RL arm of rye Kustro also possesses powdery mildew resistance gene(s) ( Fu et al, 2014 ). Additionally, the 4R chromosome of rye Imperial carries at least two genetic factors that have positive effects on wheat pollination traits ( Nguyen et al, 2015 ).…”