![]() ![]() Information about QTLs for leaf rust resistance has also been recently reviewed ( Pinto da Silva et al., 2018). The use of APR genes along with 4–5 Lr genes is a strategy that provides durable resistance.Ī number of reviews on leaf rust resistance in wheat have already been published ( Kolmer 1996 Kolmer 2013 McCallum et al., 2016 Pinto da Silva et al., 2018 Dinh et al., 2020 Figlan et al., 2020 Ghimire et al., 2020 Prasad et al., 2020). These gene complexes confer durable resistance not only against leaf rust, but also against stripe rust, stem rust, powdery mildew, and barley yellow dwarf virus ( Singh and Rajaram, 1993). Some of the APR genes like Lr34 and Lr67 have also been cloned and were found to be complex loci including Lr34/ Sr57/ Yr18/ Pm38 and Lr67/ Sr55/ Yr46/ Pm46 ( Lagudah et al., 2006 Moore et al., 2015). It is also known that ASR genes provide resistance, which breaks down within a few years, while APR provides long-term durable resistance ( Ellis et al., 2014). ![]() Lr genes provide either seedling resistance (SR), also described as all stage resistance (ASR), or adult plant resistance (APR genes), the latter expressed only at the adult plant stage, particularly after booting. It is thus obvious that a majority of race specific Lr genes individually do not provide durable resistance ( Johnson 1984). ![]() ![]() Therefore, the host resistance breaks down and is short-lived. The pathogen Pt keeps on developing new virulent races through mutations or recombination involving Avr genes new strains may also migrate from other geographical areas, and may carry one or more new Avr genes for which the corresponding R gene may be absent in the host ( Samborski 1985 Bolton et al., 2008). triticina ( Pt), which must carry the corresponding avirulence (Avr) gene, such that a specific Lr gene in the host and the corresponding specific Avr gene in the pathogen always follow a “gene-for-gene” relationship ( Flor 1946). Each individual Lr gene apparently shows resistance against a specific race of P. The study of the genetic basis of this disease and breeding for leaf rust resistance in wheat has been an important area of research ( Dyck 1993 Kolmer and Liu, 2002 Oelke and Kolmer 2005 Datta et al., 2008 Rosa et al., 2016 Aoun et al., 2017). Henn is an important disease in wheat, which causes significant yield losses, sometimes approaching up to >50% ( Riaz and Wong 2017). Leaf rust caused by the fungal pathogen Puccinia triticina Eriks. We believe that the information in this review will prove useful for wheat geneticists/breeders, not only in the development of leaf rust-resistant wheat cultivars, but also in the study of molecular mechanism of leaf rust resistance in wheat. Challenges and future perspectives of breeding for leaf rust resistance are also provided at the end of this mini-review. In the present mini-review, we provide updated information on (i) all Lr genes including those derived from alien sources and 14 other novel resistance genes (ii) a list of QTLs identified using interval mapping and MTAs identified using GWAS (particular those reported recently i.e., after 2018) and their association with known Lr genes (iii) introgression/pyramiding of individual Lr genes in commercial/prominent cultivars from 18 different countries including India. The production and productivity of wheat is adversely affected by several diseases including leaf rust, which can cause yield losses, sometimes approaching >50%. Wheat is one of the most important cereal crops in the world. 3Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, United States.2Division of Genetics and Plant Breeding, Faculty of Agriculture, Sher-e-Kashmir University of Agricultural Sciences and Technology, Wadura, India.1Department of Genetics and Plant Breeding, Chaudhary Charan Singh University, Meerut, India.Kuldeep Kumar 1 †, Irfat Jan 1,2 †, Gautam Saripalli 1,3, P. ![]()
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