Valuable New Leaf or Inflorescence Resistances Ensure Improved Management of White Rust (Albugo candida) in Mustard (Brassica juncea) Crops

Abstract

Field resistances/susceptibilities against Albugo candida race 2V were determined for 29 Indian Brassica juncea varieties and compared with resistant varieties from China (6) and Australia (7). 'Basanti' (AUDPC incidence 46.7; AUDPC severity 29.2) represents the first high-level resistance to race 2V in Indian varieties. Several others showed lower but still useful levels of resistance, including Narendra Ageti Rai-4 (AUDPC incidence 150.6; AUDPC severity 66.8) and JM1 (AUDPC incidence 167.1; AUDPC severity 83.7). Highly susceptible Indian varieties had AUDPC incidence values >200 and severity >100. 'Basanti' had least stagheads/ plant (0.32), while Narendra Ageti Rai-4 had lowest % plants with stagheads (2.48). In contrast, almost half of Indian varieties had stagheads/ plant >1 and % plants with stagheads >4, and >26 for 'Kranti'. The resistance in 'Basanti' paves the way forward towards significantly improved white rust management in mustard in India. JM06011, JM06021, JR049 from Australia and CJB-003 from China had zero leaf incidence. There were significant (P < 0.001) relationships between disease incidence with severity (R 2 0.92), stagheads/plant (R 2 0.69) and also % plants with stagheads (R 2 0.60); between disease severity with stagheads/plant (R 2 0.68) and also % plants with stagheads (R 2 0.69); and between stagheads/plant with % plants with stagheads (R 2 0.59).

Molecular characterization of disease resistance in Brassica juncea – The current status and the way forward

“…Variants of race 2 are the main A. candida types affecting B. juncea, particularly pathotype 2A (Gurung et al, 2007) and the more virulent 2V (Kaur et al, 2011c). Many studies have demonstrated resistance to A. candida in B. juncea, including specifically against race 2V (Li et al, 2007(Li et al, , 2008b(Li et al, , 2009bBarbetti et al, 2016), and also against isolates sourced from non-B. juncea hosts (Pidskalny and Rimmer, 1985;Kolte et al, 1991;Dang et al, 2000;Kaur et al, 2008b;Li et al, 2008b;Ahmad et al, 2014).…”

“…White rust, caused by A. candida , affects B . juncea and other oilseed brassicas worldwide (Saharan and Verma, 1992; Saharan, 1993; Katiyar and Chamola, 2003; Barbetti et al, 2016; Mandiriza‐Mukwirimba et al, 2016). Symptoms for white rust usually include the development of white blister‐like pustules on the underside of leaves, stems, and inflorescence of the plant, along with chlorosis on the leaf surface.…”

“…candida in B . juncea , including specifically against race 2V (Li et al, 2007, 2008b, 2009b; Barbetti et al, 2016), and also against isolates sourced from non‐ B . juncea hosts (Pidskalny and Rimmer, 1985; Kolte et al, 1991; Dang et al, 2000; Kaur et al, 2008b; Li et al, 2008b; Ahmad et al, 2014).…”

The integrated LIM-peptidase domain of the CSA1/CHS3 paired immune receptor detects changes in DA1 family peptidase inhibitors to confer Albugo candida resistance in Arabidopsis

“…White blister rust, caused by the oomycete Albugo candida , is a widespread disease of Brassica crops such as Brassica juncea (oilseed mustard) and B. oleracea vegetables [1]. White rust resistance ( WRR) genes encoding nucleotide-binding leucine-rich repeat (NLR) immune receptors were mapped in or cloned from oilseed mustard [2, 3] and Arabidopsis [4, 5].…”

In silico prediction and analysis of transmembrane‐coiled‐coil resistance gene analogues in 27Brassicaceaespecies

“…Brassicaceae species, especially the crop species, are vulnerable to various pathogenic organisms, for instance, Leptosphaeria species (L. maculans, L. biglobosa), Sclerotinia sclerotiorum, Albugo candida, Plasmodiophora brassicae, Rhizoctonia solani and Xanthomonas spp., which cause blackleg (BL), Sclerotinia stem rot (SSR), white rust (WR), clubroot (CR), hypocotyl rot (HR) and black rot (BR), respectively (Barbetti et al, 2015(Barbetti et al, , 2016Bhattacharya et al, 2014;Chattopadhyay et al, 2015;Mani et al, 2020), severely impacting their production (Thomas et al, 2022;Zhang et al, 2021). Crops overcome pathogenic diseases by having natural resistance in the form of qualitative and quantitative resistance.…”