Genome-Wide Association Mapping of Freezing Tolerance Loci in Canola (Brassica napus L.) (original) (raw)

The genetic architecture of freezing tolerance varies across the range of Arabidopsis thaliana

Plant, cell & environment, 2016

The capacity to tolerate freezing temperatures limits the geographical distribution of many plants, including several species of agricultural importance. However, the genes involved in freezing tolerance remain largely unknown. Here we describe the variation in constitutive freezing tolerance that occurs among worldwide accessions of Arabidopsis thaliana. We found that, although plants from high latitudes tend to be more freezing tolerant than plants from low latitudes, the environmental factors that shape cold adaptation differ across the species range. Consistent with this, we found that the genetic architecture of freezing tolerance also differs across its range. Conventional genome wide association studies (GWAS) helped identify a priori and other promising candidate genes. However, simultaneously modeling climate variables and freezing tolerance together pinpointed other excellent a priori candidate genes. This suggests that, if the selective factor underlying phenotypic variat...

Genome-wide association study identifies favorable SNP alleles and candidate genes for frost tolerance in pea

BMC Genomics

Background Frost is a limiting abiotic stress for the winter pea crop (Pisum sativum L.) and identifying the genetic determinants of frost tolerance is a major issue to breed varieties for cold northern areas. Quantitative trait loci (QTLs) have previously been detected from bi-parental mapping populations, giving an overview of the genome regions governing this trait. The recent development of high-throughput genotyping tools for pea brings the opportunity to undertake genetic association studies in order to capture a higher allelic diversity within large collections of genetic resources as well as to refine the localization of the causal polymorphisms thanks to the high marker density. In this study, a genome-wide association study (GWAS) was performed using a set of 365 pea accessions. Phenotyping was carried out by scoring frost damages in the field and in controlled conditions. The association mapping collection was also genotyped using an Illumina Infinium® BeadChip, which all...

Can genomics assist the phenological adaptation of canola to new and changing environments?

Crop and Pasture Science, 2016

Timing of life history events (phenology) is a key driver for the adaptation of grain crops to their environments. Anthesis (flowering) date is the critical phenological stage that has been most extensively studied. Maximum crop yield is achieved by maximising the duration of the pre-anthesis biomass accumulation phase and hence yield potential, while minimising the risk of water stress and temperature stress (heat and cold) during flowering and grain-filling stages. In this article, we review our understanding of phenology of the valuable oilseed crop canola (oilseed rape, Brassica napus L.) from the perspectives of biophysical modelling and genetics. In conjunction, we review the genomic resources for canola and how they could be used to develop models that can accurately predict flowering date in any given set of environmental conditions. Finally, we discuss how molecular marker tools can help canola breeders to continue to improve canola productivity in the light of climate chan...

Genome Wide Association Study of Frost Tolerance in Wheat

2021

Winter wheat growing areas in the Northern hemisphere are regularly exposed to heavy frost. Due to the negative impact on yield, the identification of genetic factors controlling frost tolerance (FroT) and development of tools for breeding is of prime importance. Here, we detected QTL associated with FroT by genome wide association studies (GWAS) using a diverse panel of 276 winter wheat genotypes that was phenotyped at five locations in Germany and Russia in three years. The panel was genotyped using the 90K iSelect array and SNPs in FroT candidate genes. In total, 17,566 SNPs were used for GWAS resulting in the identification of 53 markers significantly associated (LOD ≥4) to FroT, corresponding to 23 QTL regions located on 11 chromosomes (1A, 1B, 2A, 2B, 2D, 3A, 3D, 4A, 5A, 5B and 7D). The strongest QTL effect confirmed the importance of chromosome 5A for FroT. In addition, to our best knowledge, seven FroT QTLs were discovered for the first time in this study comprising QTLs on ...

Prospects for Transgenic and Molecular Breeding for Cold Tolerance in Canola (Brassica napus L.)

2012

Canola is cultivated both during winter and spring seasons in the United States and this exposes the crop to winter kill, frost, and high temperatures, during the reproductive period. The temperatures during winter and spring are known to influence all the crucial steps of the reproductive cycle including gametogenesis, pollination, fertilization and embryogenesis (Angadi, 2000). Winter rapeseed has been successfully grown in the Pacific Northwest, southern Great Plains, Midwest, and southeast regions of the USA. The hardiest cultivars will routinely survive winters in the north east of USA but survival is inconsistent further south (Rife et al., 2001). Winter-grown canola (Brassica napus L.) production is limited mostly by frost and winter-kill in the southern canola-growing regions of the United States (Singh et al., 2008). For instance, the late freeze in 2007 resulted in significant damage to most of the winter canola cultivars at the National Winter Canola Variety Trials in Ala...