Mapping resistance responses to Sclerotinia infestation in introgression lines of Brassica juncea carrying genomic segments from wild Brassicaceae B. fruticulosa

Abstract

Sclerotinia stem rot (Sclerotinia sclerotiorum) is a major disease of Brassica oilseeds. As suitable donors to develop resistant cultivars are not available in crop Brassicas, we introgressed resistance from a wild Brassicaceae species, B. fruticulosa. We produced 206 B. juncea-B. fruticulosa introgression lines (ILs). These were assessed for pollen grain fertility, genome size variations and resistance responses to Sclerotinia following stem inoculations under disease-conducive conditions. Of these, 115 ILs showing normal fertility and genome size were selected for cytogenetic characterization using florescent genomic in situ hybridization (Fl-GISH). B. fruticulosa segment substitutions were indicated in 28 ILs. These were predominantly terminal and located on B-genome chromosomes. A final set of 93 highly fertile and euploid (2n = 36) ILs were repeat-evaluated for their resistance responses during 2014–15. They were also genotyped with 202 transferable and 60 candidate gene SSRs. Association mapping allowed detection of ten significant marker trait associations (MTAs) after Bonferroni correction. These were: CNU-m157-2, RA2G05, CNU-m353-3, CNU-m442-5, ACMP00454-2, ACMP00454-3, EIN2-3-1, M641-1, Na10D09-1 and Na10D11-1. This is the first time such a molecular mapping technique has been deployed with introgression lines carrying genomic segments from B. fruticulosa, and the first to show that they possess high levels of resistance against S. sclerotiorum.

Partial stem resistance in Brassica napus to highly aggressive and genetically diverse Sclerotinia sclerotiorum isolates from Australia

“…The majority of commercial oilseed rape varieties in Australia are susceptible to SSR (Uloth et al, 2015;Rana et al, 2017). However, a growing list of publications show that partial, quantitative resistance exists in B. napus germplasm and many of its close relatives (Mei et al, 2011;Uloth et al, 2013Uloth et al, , 2015Taylor et al, 2015;Rana et al, 2017). In some cases, resistance has been identified by inoculation of the main stem of adult plants (Buchwaldt et al, 2005;Gyawali et al, 2016).…”

Enzymatic activities and pathogenesis-related genes expression in sunflower inbred lines affected bySclerotinia sclerotiorumculture filtrate

“…; Rana et al . ). In general, different parts of sunflower plant display independent types of tolerance to S. sclerotiorum infection (Tuorvieille and Vear ).…”

“…Earlier studies suggested that resistance to S. sclerotiorum is polygenic in nature (Cheng et al 2009;Rana et al 2017). In general, different parts of sunflower plant display independent types of tolerance to S. sclerotiorum infection (Tuorvieille and Vear 1990).…”

Identifying chromosomal introgressions from a wild species Arachis diogoi into interspecific peanut hybrids

“…Previous studies have shown that the wild species typically have higher resistance to abiotic and biotic stresses in comparison with cultivated peanut (Brasileiro et al, 2015; Han et al, 2017; Michelotto et al, 2017). Several successful cases were reported on introgression of disease resistance from wild‐type species into cultivated crops through interspecific hybridization such as potato ( Solanum tuberosum ) and brown mustard ( Brassica juncea ) (Boschi et al, 2017; Rana et al, 2017) and peanut (Fávero, Santos, Simpson, Valls, & Vello, 2015; Michelotto et al, 2015; Sharma, Kalia, Singh, & Sharma, 2017; Simpson, Nelson, Starr, Woodard, & Smith, 1993; Stalker & Lynch, 2002). Therefore, a wild species with known resistance to spotted wilt can be used to create peanut interspecific hybrid lines with superior host resistance.…”