Marker Assisted Gene Pyramiding (MAGP) for bacterial blight and blast resistance into mega rice variety “Tellahamsa”

Abstract

Bacterial blight (BB) and fungal blast diseases are the major biotic constraints that limit rice productivity. To sustain yield improvement in rice, it is necessary to developed yield potential of the rice varieties by incorporation of biotic stress resistance genes. Tellahamsa is a welladapted popular high yielding rice variety in Telangana state, India. However, the variety is highly susceptible to BB and blast. In this study, simultaneous stepwise transfer of genes through marker-assisted backcross breeding (MABB) strategy was used to introgress two major BB (Xa21 and xa13) and two major blast resistance genes (Pi54 and Pi1) into Tellahamsa. In each generation (from F 1 to ICF 3) foreground selection was done using gene-specific markers viz., pTA248 (Xa21), xa13prom (xa13), Pi54MAS (Pi54) and RM224 (Pi1). Two independent BC 2 F 1 lines of Tellahamsa/ISM (Cross-I) and Tellahamsa/NLR145 (Cross-II) possessing 92% and 94% recurrent parent genome (RPG) respectively were intercrossed to develop ICF1-ICF 3 generations. These gene pyramided lines were evaluated for key agro-morphological traits, quality, and resistance against blast at three different hotspot locations as well as BB at two locations. Two ICF 3 gene pyramided lines viz., TH-625-159 and TH-625-491 possessing four genes exhibited a high level of resistance to BB and blast. In the future, these improved Tellahamsa lines could be developed as mega varieties for different agro-climatic zones and also as potential donors for different pre-breeding rice research.

Development of white-grain pre-harvest sprouting tolerant and pyramided protein-rich leaf rust resistant wheats using molecular breeding

“…RPG recovery in the two crosses in the present study did not differ from several earlier wheat breeding programmes where MABB was used for introgression of genes/QTL for biotic and abiotic stresses in wheat (Yadav et al 2015;Mallick et al 2015;Vishwakarma et al 2016;Rai et al 2018;Randhawa et al 2019;Todkar et al 2020: Gautam et al 2020a). This con rmed the utility of MABB for effective introgression of genes/QTL into the agronomically superior genotypes associated with recovery of recurrent parent genome in a relatively short time as also reported earlier in wheat (Mallick et al 2015), rice (Divya et al 2015;Ellur et al 2016;Ramalingam et al 2020;Jamaloddin et al 2020), and maize (Sureshkumar et al 2014;Kaur R et al 2020).…”

Rice Blast Disease in India: Present Status and Future Challenges

“…For example, in a recent study, gene pyramided lines were evaluated for key agro-morphological traits, quality, and resistance against blast at different hotspot locations. Two ICF 3 genes, pyramided lines viz., TH-625-159, and TH-625-491 possessing Pi54 and Pi1 genes, exhibited a high level of resistance to blast [195]. Often gene pyramiding, ably supported by MAS, involves assembling more than one gene for different insect pests or diseases or a combination of both.…”

Molecular Breeding Strategy and Challenges Towards Improvement of Downy Mildew Resistance in Cauliflower (Brassica oleracea var. botrytis L.)

“…Marker-assisted gene pyramiding of resistance QTLs have been successfully applied in several crops consequently producing a number of varieties and lines with improved resistances against biotic stresses, such as late blight, bacterial blight, gall midge, mosaic viruses, powdery mildew and many abiotic stresses, such as salinity, drought, heat, and cold with a higher yield and desired nutritional quality (reviewed by Dormatey et al, 2020 ). Especially, the multi-loci polymerization resistance breeding is a success story in rice where plant scientists successfully utilized this technique to accomplish durable resistance against various diseases such as gall midge ( Das and Rao, 2015 ), blast ( Jamaloddin et al, 2020 ), brown planthopper ( Liu et al, 2016 ), bacterial blight ( Singh et al, 2001 ; Joseph et al, 2004 ; Jamaloddin et al, 2020 ; Ramalingam et al, 2020 ), sheath blight ( Ramalingam et al, 2020 ), blast and bacterial blight ( Narayanan et al, 2002 ), bacterial, sheath blight and stem borer ( Datta et al, 2002 ) etc. Wu et al (2019) identified 37 SNP polymerization regions for 36 agronomic traits in 287 pepper accessions which could be the focus of molecular marker development to improve the efficiency of multi-trait pyramid breeding.…”