Association analysis of resistance to cereal cyst nematodes (<i>Heterodera avenae</i>) and root lesion nematodes (<i>Pratylenchus neglectus</i> and <i>P. thornei</i>) in CIMMYT advanced spring wheat lines for semi-arid conditions

Abstract

To identify loci linked to nematode resistance genes, a total of 126 of CIMMYT advanced spring wheat lines adapted to semi-arid conditions were screened for resistance to Heterodera avenae, Pratylenchus neglectus, and P. thornei, of which 107 lines were genotyped with 1,310 DArT. Association of DArT markers with nematode response was analyzed using the general linear model. Results showed that 11 markers were associated with resistance to H. avenae (pathotype Ha21), 25 markers with resistance to P. neglectus, and 9 significant markers were identified to be linked with resistance to P. thornei. In this work we confirmed that chromosome 4A (~90–105 cM) can be a source of resistance to P. thornei as has been recently reported. Other significant markers were also identified on chromosomal regions where no resistant genes have been reported for both nematodes species. These novel QTL were mapped to chromosomes 5A, 6A, and 7A for H. avenae; on chromosomes 1A, 1B, 3A, 3B, 6B, 7AS, and 7D for P. neglectus; and on chromosomes 1D, 2A, and 5B for P. thornei and represent potentially new loci linked to resistance that may be useful for selecting parents and deploying resistance into elite germplasm adapted to regions where nematodes are causing problem.

Effect of cereal cyst nematode Heterodera filipjevi on wheat yields in Turkey

“…Average grain yield for each treatment was calculated and yield reduction percentage (%) was calculated based on the values derived from the treated and nontreated plots. Dababat et al (2016) reported 484 accessions with resistant reactions that were classified into one of five distinctive groups based on the RF: resistant (R) = RF equal to or less than 1; moderately resistant (MR) = RF between 1 and 2, a few more cysts than in a resistant group; moderately susceptible (MS) = RF between 2 and 3, distinctly more cysts than in a resistant group, but less than in a susceptible group; susceptible (S) = RF between 3 and 4, more cysts than in a susceptible group; and highly susceptible (HS) = RF above 4, cyst number higher than in a susceptible group and taking into account the reaction of the known control lines used in the study. Moreover, Smiley et al (2004) described accession tolerance reactions by classifying them into 4 groups based on RF and yield potential.…”

Cereal Root Interactions with Soilborne Pathogens—From Trait to Gene and Back

“…Native sources of resistance to cereal cyst nematodes include the Cre genes from wild relatives of wheat or adapted cultivars. These have been deployed and combined for resistance against Heterodera avenae [14]. The wheat DArT array was used to discover markers for new nematode resistance loci in 107 spring wheat genotypes from the CIMMYT semi-arid wheat screening nursery [14].…”

“…These have been deployed and combined for resistance against Heterodera avenae [14]. The wheat DArT array was used to discover markers for new nematode resistance loci in 107 spring wheat genotypes from the CIMMYT semi-arid wheat screening nursery [14]. Genotypes grown in this nursery are scored for yield under low or high rainfall (depending upon the year) in soil containing nematodes, root rot pathogens, and other biotic challenges.…”

“…Wheat and rice are major sources of nutrition for 40% and over 50% of the world's population, respectively [14,15]. Wheat, rice, and barley provide about 56% of the caloric content and 50% of…”

Transgenic Strategies for Enhancement of Nematode Resistance in Plants

“…The cultural practices for nematode management include solarization (Katan, 1981), flooding (MacGuidwin, 1993), fallowing (Brodie and Murphy, 1975), crop rotation (Westphal, 2011; Dababat et al, 2015), cover crops (Kirkegaard and Sarwar, 1998), and a combination of some of these (Singh et al, 2009). Similarly, the utilization of natural host resistance from various crop species is a preferred approach for nematode management because it is environmentally safe and cost-saving option as compared to chemical control (Williamson and Kumar, 2006; Dababat et al, 2016). In chemical control, fumigants, organophosphates, and carbamates have been used for inhibiting nematode populations in the soil.…”