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Biology subjects

Welch, S.

Publications and source records attributed to Welch, S..

2 recordsLinked to original sources

Integrating transcriptomic network reconstruction and QTL analyses reveals mechanistic connections between genomic architecture and Brassica rapa development

Plant developmental dynamics can be heritable, genetically correlated with fitness and yield, and undergo selection. Therefore, characterizing the mechanistic connections between the genetic architecture governing plant development and the resulting ontogenetic dynamics of plants in field settings is critically important for agricultural production and evolutionary ecology. We use a hierarchical Bayesian Function-Valued Trait (FVT) approach to estimate Brassica rapa growth curves throughout ontogeny, across two treatments and in two growing seasons. We find that the shape of growth curves is relatively plastic across environments compared to final height, and that there are trade-offs between growth rate and duration. We determined that combining FVT Quantitative Trait Loci (QTL) and genes/eigengene expression identified via transcriptomic co-expression network reconstructions best characterized phenotypic variation. Further, targeted eQTL analyses identified regulatory hotspots that colocalized with FVT QTL and co-expression network identified genes and mechanistically link FVT QTL with structural trait variation throughout development in agroecologically relevant field settings.

genomics↗

Problems with Estimating Anthesis Phenology Parameters in Zea mays: Consequences for Combining Ecophysiological Models with Genetics

Ecophysiological crop models encode intra-species behaviors using constant parameters that are presumed to summarize genotypic properties. Accurate estimation of these parameters is crucial because much recent work has sought to link them to genotypes. The original goal of this study was to fit the anthesis date component of the CERES-Maize model to 5266 genetic lines grown at 11 site-years and genetically map the resulting parameter estimates. Although the resulting estimates had high predictive quality, numerous artifacts emerged during estimation. The first arose in situations where the model was unable to express the observed data for many lines, which ended up sharing the same parameter value. In the second (2254 lines), the model reproduced the data but there were often many parameter sets that did so equally well (equifinality). These artifacts made genetic mapping impossible, thus, revealing cautionary insights regarding a major current paradigm for linking process based models to genetics.

genetics↗