No abstract

While the genetic control of wheat processing characteristics such as dough rheology is well understood, limited information is available concerning the genetic control of baking parameters, particularly sponge and dough (S&D) baking. In this study, a quantitative trait loci (QTL) analysis was performed using a population of doubled haploid lines derived from a cross between Australian cultivars Kukri x Janz grown at sites across different Australian wheat production zones (Queensland in 2001 and 2002 and Southern and Northern New South Wales in 2003) in order to examine the genetic control of protein content, protein expression, dough rheology and sponge and dough baking performance. The study highlighted the inconsistent genetic control of protein content across the test sites, with only two loci (3A and 7A) showing QTL at three of the five sites. Dough rheology QTL were highly consistent across the 5 sites, with major effects associated with the Glu-B1 and Glu-D1 loci. The Glu-D1 5 + 10 allele had consistent effects on S&D properties across sites; however, there was no evidence for a positive effect of the high dough strength Glu-B1-al allele at Glu-B1. A second locus on 5D had positive effects on S&D baking at three of five sites. This study demonstrated that dough rheology measurements were poor predictors of S&D quality. In the absence of robust predictive tests, high heritability values for S&D demonstrate that direct selection is the current best option for achieving genetic gain in this product category.

No abstract

Using large-scale field surveys across 12 estuaries in two provinces in Atlantic Canada, we analyzed changes in phytoplankton and benthic macroalgal communities as well as the canopy structure of eelgrass beds and quantified their carbon and nitrogen storage with increasing eutrophication. As eutrophication increased, phytoplankton biomass increased on average 1.8 times and phaeopigments doubled. Among macroalgae, the epiphytic Ulothrix speciosa increased 40 times in New Brunswick, and benthic Ulva lactuca 670 times in Prince Edward Island covering 61% of the bottom. Eelgrass showed a significant increase in leaf length and declines in shoot density and aboveground and belowground biomass, consistent with increased shading by opportunistic algae. As eelgrass biomass declined, so did the carbon storage capacity of the habitat. Nitrogen storage only declined in belowground eelgrass beds due to increasing tissue nitrogen content above ground with eutrophication. Despite province-and species-specific responses of primary producers to nutrient loading, principal component analysis revealed an overall shift from perennial eelgrass to opportunistic macroalgae and phytoplankton with eutrophication at the regional scale, indicating generalized eutrophication effects on primary producer assemblages.