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To meet the increasing demand of wood biomass worldwide in the context of climate change, developing improved forest tree varieties for high productivity in water-limited conditions is becoming a major issue. This involves breeding for genotypes combining high growth and moderate water loss and thus high water-use efficiency (WUE). The present work provides original data about the genetics of intrinsic WUE (the ratio between net CO2 assimilation rate and stomatal conductance, also estimated by carbon isotope composition of plant material; δ13C) and its relation to growth in Pinus pinaster Ait. First, heritability for δ13C was estimated (0.29) using a 15-year-old progeny trial (Landes provenance), with no significant differences among three sites contrasting in water availability. High intersite correlations (0.63–0.91) and significant but low genotype–environment interactions were detected. Secondly, the genetic architectures of δ13C and growth were studied in a three-generation inbred pedigree, introducing the genetic background of a more-drought-adapted parent (Corsican provenance), at ages of 2 years (greenhouse) and 9 years (plantation). One of the quantitative trait loci (QTLs) identified in the field experiment, explaining 67% of the phenotypic variance, was also found among the QTLs detected in the greenhouse experiment, where it colocalized with QTLs for intrinsic WUE and stomatal conductance. This work was able to show that higher WUE was not genetically linked to less growth, allowing thus genetic improvement of water use. As far as is known, the heritability and QTL effects estimated here are based on the highest number of genotypes measured to date.

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The storage of fresh raw milk at low temperature does not prevent proliferation of psychrotrophic bacteria that can produce heat-resistant proteolytic enzymes contributing to the reduced shelf life of dairy products. This study aimed to identify the dominant psychrotrophic proteolytic enzyme-producing population of raw milk from Brazil. Raw milk samples collected in 3 different cooling tanks in Brazil were stored at optimal (45 h at 4 °C followed by 3 h at 7 °C) and suboptimal (45 h at 7 °C followed by 3 h at 10 °C) conditions to simulate farm storage and transportation allowed by Brazilian laws. The highly proteolytic enzyme-producing strains isolated from stored cold raw milk were characterized by repetitive sequence-based Polymerase Chain Reaction (PCR) analysis. This clustering resulted in 8 different clusters and 4 solitary fingerprints. The most proteolytic isolates from each rep-cluster were selected for identification using miniaturized kit, 16S rDNA and rpoB gene sequencing. Serratia liquefaciens (73.9%) and Pseudomonas spp. (26.1%) were identified as the dominant psychrotrophic microorganisms with high spoilage potential. The knowledge of milk spoilage microbiota will contribute to improved quality of milk and dairy products.

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Sugarcane (Saccharum spp.) bagasse is recognized as a promising feedstock for cellulosic ethanol production. e development of high-quality crop cultivars through plant breeding is a way to improve feedstock quality. is study aimed to directly and indirectly quantify the e ects of agronomic characteristics on the sacchari cation of sugarcane bagasse samples and to identifying the characteristics that can be used as reliable tools for the selection of genotypes for a better biofuel feedstock. e lignin content was determined in bagasse samples of 286 clones from 13 half-sib families. Twenty clones showing a more contrasting lignin content were analyzed for the cellulose and hemicellulose composition in bagasse. ey di ered statistically for cellulose and hemicellulose contents and also for the e ciency of cellulose to glucose conversion. Clones with the highest dry biomass content also had the highest ber content and were grouped among the clones exhibiting the highest lignin content. Lignin content was statistically signi cant and positively correlated with ber (r = 0.485, p < 0.05) and plant biomass (r = 0.654, p < 0.01), and hemicellulose content was statistically signi cant and positively correlated with number of internodes (r = 0.623, p < 0.01). Lignin content and plant biomass had large negative direct e ects (0.405 and 0.784, respectively) on glucose released by enzymatic hydrolysis. Variation among clones for plant productivity parameters and chemical composition of bagasse could be exploited by breeding to increase the amount of cellulosic ethanol produced. Lignin content and plant biomass were the most important components with direct and negative in uences on the conversion of cellulose to glucose.