Expanding the utilization of sustainable plant products in aquafeeds: a review

Continued growth and intensification of aquaculture production depends upon the development of sustainable protein sources to replace fish meal in aquafeeds. This document reviews various plant feedstuffs, which currently are or potentially may be incorporated into aquafeeds to support the sustainable production of various fish species in aquaculture. The plant feedstuffs considered include oilseeds, legumes and cereal grains, which traditionally have been used as protein or energy concentrates as well as novel products developed through various processing technologies. The nutritional composition of these various feedstuffs are considered along with the presence of any bioactive compounds that may positively or negatively affect the target organism. Lipid composition of these feedstuffs is not specifically considered although it is recognized that incorporating lipid supplements in aquafeeds to achieve proper fatty acid profiles to meet the metabolic requirements of fish and maximize human health benefits are important aspects. Specific strategies and techniques to optimize the nutritional composition of plant feedstuffs and limit potentially adverse effects of bioactive compounds are also described. Such information will provide a foundation for developing strategic research plans for increasing the use of plant feedstuffs in aquaculture to reduce dependence of animal feedstuffs and thereby enhance the sustainability of aquaculture

Perspectives on Low Temperature Tolerance and Vernalization Sensitivity in Barley: Prospects for Facultative Growth Habit

One option to achieving greater resiliency for barley production in the face of climate change is to explore the potential of winter and facultative growth habits: for both types, low temperature tolerance (LTT) and vernalization sensitivity are key traits. Sensitivity to short-day photoperiod is a desirable attribute for facultative types. In order to broaden our understanding of the genetics of these phenotypes, we mapped quantitative trait loci (QTLs) and identified candidate genes using a genome-wide association studies (GWAS) panel composed of 882 barley accessions that was genotyped with the Illumina 9K single-nucleotide polymorphism (SNP) chip. Fifteen loci including 5 known and 10 novel QTL/genes were identified for LTT—assessed as winter survival in 10 field tests and mapped using a GWAS meta-analysis. FR-H1, FR-H2, and FR-H3 were major drivers of LTT, and candidate genes were identified for FR-H3. The principal determinants of vernalization sensitivity were VRN-H1, VRN-H2, and PPD-H1. VRN-H2 deletions conferred insensitive or intermediate sensitivity to vernalization. A subset of accessions with maximum LTT were identified as a resource for allele mining and further characterization. Facultative types comprised a small portion of the GWAS panel but may be useful for developing germplasm with this growth habit

Perspectives on Low Temperature Tolerance and Vernalization Sensitivity in Barley: Prospects for Facultative Growth Habit

15 Pags.- 5 Figs.- 3 TAbls.- Supp. Mat. Copyright Owner, the Authors. Under LicenceCC BY 4.0.One option to achieving greater resiliency for barley production in the face of climate change is to explore the potential of winter and facultative growth habits: for both types, low temperature tolerance (LTT) and vernalization sensitivity are key traits. Sensitivity to short-day photoperiod is a desirable attribute for facultative types. In order to broaden our understanding of the genetics of these phenotypes, we mapped quantitative trait loci (QTLs) and identified candidate genes using a genome-wide association studies (GWAS) panel composed of 882 barley accessions that was genotyped with the Illumina 9K single-nucleotide polymorphism (SNP) chip. Fifteen loci including 5 known and 10 novel QTL/genes were identified for LTT—assessed as winter survival in 10 field tests and mapped using a GWAS meta-analysis. FR-H1, FR-H2, and FR-H3 were major drivers of LTT, and candidate genes were identified for FR-H3. The principal determinants of vernalization sensitivity were VRN-H1, VRN-H2, and PPD-H1. VRN-H2 deletions conferred insensitive or intermediate sensitivity to vernalization. A subset of accessions with maximum LTT were identified as a resource for allele mining and further characterization. Facultative types comprised a small portion of the GWAS panel but may be useful for developing germplasm with this growth habit.Support was provided by the USDA-NIFA TCAP Project no. 2011-68002-30029.Peer reviewe

Perspectives on Low Temperature Tolerance and Vernalization Sensitivity in Barley: Prospects for Facultative Growth Habit

[EN] One option to achieving greater resiliency for barley production in the face of climate change is to explore the potential of winter and facultative growth habits: for both types, low temperature tolerance (LTT) and vernalization sensitivity are key traits. Sensitivity to short-day photoperiod is a desirable attribute for facultative types. In order to broaden our understanding of the genetics of these phenotypes, we mapped quantitative trait loci (QTLs) and identified candidate genes using a genome-wide association studies (GWAS) panel composed of 882 barley accessions that was genotyped with the Illumina 9K single-nucleotide polymorphism (SNP) chip. Fifteen loci including 5 known and 10 novel QTL/genes were identified for LTT—assessed as winter survival in 10 field tests and mapped using a GWAS meta-analysis. FR-H1, FR-H2, and FR-H3 were major drivers of LTT, and candidate genes were identified for FR-H3. The principal determinants of vernalization sensitivity were VRN-H1, VRN-H2, and PPD-H1. VRN-H2 deletions conferred insensitive or intermediate sensitivity to vernalization. A subset of accessions with maximum LTT were identified as a resource for allele mining and further characterization. Facultative types comprised a small portion of the GWAS panel but may be useful for developing germplasm with this growth habitSISupport was provided by the USDA-NIFA TCAP Project no. 2011-68002-3002

Population Genomics Related to Adaptation in Elite Oat Germplasm

Six hundred thirty five oat ( L.) lines and 4561 single-nucleotide polymorphism (SNP) loci were used to evaluate population structure, linkage disequilibrium (LD), and genotype–phenotype association with heading date. The first five principal components (PCs) accounted for 25.3% of genetic variation. Neither the eigenvalues of the first 25 PCs nor the cross-validation errors from = 1 to 20 model-based analyses suggested a structured population. However, the PC and = 2 model-based analyses supported clustering of lines on spring oat vs. southern United States origin, accounting for 16% of genetic variation ( < 0.0001). Single-locus -statistic () in the highest 1% of the distribution suggested linkage groups that may be differentiated between the two population subgroups. Population structure and kinship-corrected LD of = 0.10 was observed at an average pairwise distance of 0.44 cM (0.71 and 2.64 cM within spring and southern oat, respectively). On most linkage groups LD decay was slower within southern lines than within the spring lines. A notable exception was found on linkage group Mrg28, where LD decay was substantially slower in the spring subpopulation. It is speculated that this may be caused by a heterogeneous translocation event on this chromosome. Association with heading date was most consistent across location-years on linkage groups Mrg02, Mrg12, Mrg13, and Mrg24

Astaxanthin improves preserved semen quality at 17 degrees C by enhancing sperm antioxidant and motility properties

Porcine sperm is rich in polyunsaturated fatty acids; therefore, it is highly susceptible to oxidative damage during storage. Inhibition of oxidative stress during preservation is essential for maintaining sperm motility. Astaxanthin is a potent antioxidant used in the cosmetic and pharmaceutical industries. This study aimed to explore the effect of supplementing astaxanthin as an extender of porcine semen preservation dilutions at 17 degrees C. Various concentrations of astaxanthin were added to diluted porcine semen at 17 degrees C. We performed computer-assisted semen analysis, evaluation of plasma membrane integrity and acrosome integrity, and measurement of total antioxidant activity, malondialdehyde (MDA) content, reactive oxygen species levels, superoxide dismutase (SOD) activity, catalase (CAT) activity, glutathione peroxidase (GSH-PX) activity and sperm motility parameters. Compared with the control group, the addition of 0.25 mu g/ml astaxanthin group significantly improved sperm motility parameters stored on the fifth day; these were increased levels of sperm SOD, GSH-PX and CAT (p < .05), increased sperm adenosine trisphosphate and lactate dehydrogenase levels and decreased sperm MDA levels (p < .05). These findings suggest that adding 0.25 mu g/ml of astaxanthin improves the quality of porcine semen stored at 17 degrees C. Our findings provide theoretical support for developing new protective agents critical for preserving pig semen at 17 degrees C

QTL mapping of shoot and seed traits impacted by Drought in Barley using a recombinant inbred line Population

Abstract Background With ongoing climate change, drought events are severely limiting barley production worldwide and pose a significant risk to the malting, brewing and food industry. The genetic diversity inherent in the barley germplasm offers an important resource to develop stress resiliency. The purpose of this study was to identify novel, stable, and adaptive Quantitative Trait Loci (QTL), and candidate genes associated with drought tolerance. A recombinant inbred line (RIL) population (n = 192) developed from a cross between the drought tolerant ‘Otis’ barley variety, and susceptible ‘Golden Promise’(GP) was subjected to short-term progressive drought during heading in the biotron. This population was also evaluated under irrigated and rainfed conditions in the field for yields and seed protein content. Results Barley 50k iSelect SNP Array was used to genotype the RIL population to elucidate drought-adaptive QTL. Twenty-three QTL (eleven for seed weight, eight for shoot dry weight and four for protein content) were identified across several barley chromosomes. QTL analysis identified genomic regions on chromosome 2 and 5 H that appear to be stable across both environments and accounted for nearly 60% variation in shoot weight and 17.6% variation in seed protein content. QTL at approximately 29 Mbp on chromosome 2 H and 488 Mbp on chromosome 5 H are in very close proximity to ascorbate peroxidase (APX) and in the coding sequence of the Dirigent (DIR) gene, respectively. Both APX and DIR are well-known key players in abiotic stress tolerance in several plants. In the quest to identify key recombinants with improved tolerance to drought (like Otis) and good malting profiles (like GP), five drought tolerant RILs were selected for malt quality analysis. The selected drought tolerant RILs exhibited one or more traits that were outside the realms of the suggested limits for acceptable commercial malting quality. Conclusions The candidate genes can be used for marker assisted selection and/or genetic manipulation to develop barley cultivars with improved tolerance to drought. RILs with genetic network reshuffling necessary to generate drought tolerance of Otis and favorable malting quality attributes of GP may be realized by screening a larger population