Characterization of New Wheat-<b><i>Dasypyrum breviaristatum</i></b> Introgression Lines with Superior Gene(s) for Spike Length and Stripe Rust Resistance

Abstract

Dasypyrum breviaristatum (genome V^bV^b) contains potentially important traits for commercial wheat production. Chromosome 2V^b of D. breviaristatum carries several desirable agronomic characters, including long spike length as well as enhanced resistance to stripe rust, which are expressed in a common wheat background. In this study, wheat-D. breviaristatum 2V^b deletion lines were produced and identified by fluorescence in situ hybridization (FISH), and 74 molecular markers specific to D. breviaristatum chromosome 2V^b were physically localized in 4 distinct chromosomal regions. New wheat-D. breviaristatum 2V^b translocation lines were also characterized by FISH. The breakpoint of the translocation T3AS.3AL-2V^bS was determined by physically mapped molecular markers. Field evaluation revealed that genes affecting plant height and spike length are located on fraction length (FL) 0.65-1.00 of 2V^bS, while the stripe rust resistance gene(s) are located on FL 0.40-1.00 of D. breviaristatum chromosome 2V^bL. The newly characterized wheat-Dasypyrum chromosomal introgressions are of potential value for the improvement of the yield and disease resistance of wheat.

Diversified Chromosome Rearrangements Detected in a Wheat‒Dasypyrum breviaristatum Substitution Line Induced by Gamma-Ray Irradiation

“…Wang et al [27] identified the two wheat‒ D. breviaristatum 2V b introgression lines D11-5 (2V b ) and D2230 (deletion 2V b -1) by Oligo-pSc119.2, Oligo-pTa535 and Oligo-(CAA) 7 , and constructed a karyotype of chromosome 2V b . In the present study, sequential ND-FISH was performed with new Oligo probes Oligo-pDb12H, Oligo-B11, Oligo-k288, Oligo-D, Oligo-713, and Oligo-k566 for distinguishing the wheat and 2V b chromosomes, and then we obtained an updated FISH karyotype for 2V b (Figure 1).…”

“…In the present study, we report extensive chromosomal rearrangements in the D. breviaristatum 2V b (2D) [25] and 2V b -1(2D) [27] substitution lines induced by gamma ray radiation. The breakage and re-fusion among wheat chromosomes and between wheat and D. breviaristatum chromosomes were investigated by using ND-FISH.…”

“…These results indicated that novel agronomic traits for facilitating wheat breeding programs can be obtained by inducing irradiation through inheritable multiple chromosome translocations. Furthermore, a wheat‒ D. breviaristatum homologous translocation line, T2B:2V b -1, can serve as a bridge material for transferring the stripe rust resistance gene(s) located on 2V b L (FL 0.40–1.00) to the wheat background [27]. These non-Robertsonian translocations have high potential to clarify our understanding of the contribution of chromosomal rearrangements to agronomic traits in the wheat genome.…”

“…A fertility-improved partial amphiploid TDH-2 (AABBV b V b ), was produced and identified from progeny of a Chinese Spring wheat‒ D. breviaristatum amphiploid following self-pollination [24]. One wheat‒ D. breviaristatum 7V b disomic addition line and a 2V b (2D) substitution line with high resistance to wheat stripe rust races, and a 1V b substitution line with novel HMW-GS gene have been characterized by integrated molecular and concise cytogenetic techniques sequentially [25,26,27].…”

Использование Генетического Потенциала Многолетних Дикорастущих Злаков В Селекци-Онном Улучшении Пшеницы

“…На основе амфиплоидов, полученных гибридизацией пшеницы и D. breviaristatum, созданы дополненные линии, несущие гены устойчивости к полосатой, стеблевой ржавчине, мучнистой росе (116,117). С помощью молекулярных маркеров выявлено замещение 2V b (2D) в линии мягкой пшеницы, устойчивой к полосатой ржавчине (118), на основе которой получена интрогрессивная устойчивая форма с более длинным колосом (119). Интрогрессии сегментов хромосомы 1V b позволили создать формы пшеницы с новыми высокомолекулярными глютенинами (119,120).…”