Breeding Success Research Articles

History and prospects of flax genetic markers

Flax (Linum usitatissimum L.) is known as a dual-purpose crop, producing both fiber and oil, which have a wide range of uses. Successful flax breeding requires knowledge on the genetic determinants of flax traits. The former identification of molecular markers for valuable traits used labor-intensive and sometimes poorly reproducible approaches. However, they allowed an assessment of the genetic diversity of flax and its relatives, the construction of linkage maps, and the identification of some markers for important characteristics. The sequencing of flax whole genome triggered the development of genome-wide association studies (GWAS) and quantitative trait locus (QTL) mapping. QTLs and quantitative trait nucleotides (QTNs) were identified for valuable seed- and fiber-related features and for resistance to biotic and abiotic stressors. Cost-effective and accurate analysis of large number of genotypes for multiple markers simultaneously using microarrays or targeted deep sequencing became available, as well as HRM, TaqMan, KASP, and other fluorescence-based high-throughput methods for detecting DNA polymorphisms. However, most DNA markers identified in flax are ambiguously linked to trait expression and are not universally applicable. A major challenge remains the lack of knowledge on functional polymorphisms. To date, only a few are known, mainly mutations in the FAD3 genes responsible for reduced linolenic acid content in linseed oil. For the further development of marker-assisted and genomic selection of flax, it is necessary to analyze exhaustively phenotyped sample sets, to identify DNA polymorphisms that determine valuable traits, and to develop efficient DNA test systems.

New information on the breeding and moulting ecology of the Eastern population of Lesser White-fronted Goose Anser erythropus from GPS/GSM tracking data

Summary The Eastern population of the Lesser White-fronted Goose (EPLWFG) Anser erythropus is shared between Russia and China. The summer range of the EPLWFG has been recognised as a continuous area extending from the Olenyok River in the west to the Anadyr River in the east and northwards from 64°N. The aim of this study was to provide information on breeding behaviour; nest-sites, nesting habitats, and time of nesting; nesting success; timing of summer movements including moult migration; moult timing, duration, and moulting habitats; site fidelity; and the effect of human presence. To accomplish this, we combined the results from field surveys with GPS/GSM tracking. A total of 30 summer tracks from 19 individual EPLWFG were analysed. We estimated breeding propensity in 93.8% of adult LWFG, and this factor did not seem to depend on breeding success in the previous season. Reproductive success was 13.3% in all nesting attempts. Non-breeders arrived three-week later and departed a week earlier. The EPLWFG are highly mobile during the summer. The core moulting site for the entire EPLWFG was discovered by this study and is located along the lower reaches of the San-Yuryakh and Kyuanekhtyakh rivers flowing towards the Omulyakhskaya Bay of the East Siberian Sea. The EPLWFG flightless period was 24.8 ± 2.8 days. A part of failured EPLWFG (43.7 %) migrated back to its early summer breeding/staging site after having completed moult. The strong site fidelity (100%) of adult birds to both nesting and moulting sites promotes the formation of local breeding populations, which could be considered conservation units if genetic studies support this differentiation. The EPLWFG selects the remotest and least human-accessible area for their remigial moult, and the main site was discovered with the help of tracking.

The effect of seasonality on the foraging behaviour and breeding success of a tropical marine top predator

The effect of seasonality on the foraging behaviour and breeding success of a tropical marine top predator

Differences between mates at the TLR1Lb locus are associated with lower reproductive success in a long-lived seabird

Abstract Genetic diversity can influence fitness components such as survival and reproductive success. Yet the association between genetic diversity and fitness based on neutral loci is sometime very weak and inconsistent, with relationships varying among taxa due to confounding effects of population demography and life history. Fitness-diversity relationships are likely to be stronger and more consistent for genes known to influence phenotypic traits, such as immunity-related genes, and may also depend on the genetic differences between breeding partners. We recorded breeding success of individuals and breeding pairs over 20 years to evaluate the relationships between reproductive success and both neutral genetic variation (using 7,830 single nucleotide polymorphisms) and functional variation (four toll-like receptor [TLRs] loci) with reproductive success in thick-billed murres (Uria lomvia). Individual genetic diversity (both neutral and functional) was unrelated to reproductive success, but surprisingly, successful multi-year reproductive success decreased with the genetic difference between breeding partners at TLR1Lb. This result may be due to an advantage of specific alleles at TLR1Lb. This study is one of few addressing both individual genetic variation and genetic similarity between mates at both neutral and functional variation in a long-lived bird.

Diallel analysis and combining ability in crosses between Glycine max and Glycine soja aiming at improving protein, oil and fatty acid contente

The study evaluated the genetic variability in soybean crosses, aiming to improve grain quality for protein, oil and fatty acid contents. Two Glycine max cultivars were crossed with two Glycine soja lines, and the progenies were analyzed for protein, oil and fatty acid contents. The results indicated that the G. soja species has great potential to increase protein and oil contents in commercial cultivars. The choice of parents is crucial for the success of breeding, and the interaction between specific genes also influences grain composition. Genetic variability was observed for all traits, with different levels of influence of general combining ability (GCA) and specific combining ability (SCA). GCA was important in all cases, while SCA was significant for most traits, except for protein content. The study highlights the complexity of the inheritance of soybean grain composition and provides valuable information for the development of superior cultivars, with higher protein and oil contents and optimized fatty acid profiles for various applications.

Advancements in Palynology: Enhancing Plant Breeding through Pollen Studies

Palynology, the study of pollen and spores, has emerged as a vital discipline in plant science, with applications extending into plant breeding. This review explores the role of palynology in understanding reproductive biology, enhancing breeding programs, overcoming hybridization barriers and addressing challenges like male sterility, stress tolerance and species compatibility. Advanced techniques like transcriptomics reveal gene expression profiles, while proteomics and metabolomics provide insights into fertility and stress responses. Pollen-mediated transformation and CRISPR-Cas9 gene editing facilitate targeted trait improvements, with pollen-specific promoters aiding hybrid breeding. Additionally, molecular tools support pollen viability testing, gene flow studies, and stress tolerance research, contributing to hybrid seed production and environmental adaptability. Palynology also ensures biosafety by tracking transgenic pollen, making it an integral component of sustainable crop improvement strategies. Case studies illustrate its impact on cereals, legumes and horticultural crops. The article concludes by highlighting challenges and future directions for integrating palynological studies with emerging technologies to improve plant breeding outcomes. Plant breeding aims to develop superior crop varieties with desirable traits such as higher yields, resistance to biotic and abiotic stresses, improved quality and adaptability to diverse environments. Successful breeding hinges on understanding the reproductive biology of plants, particularly pollen, which serves as the carrier of male gametes.

Effects of experimental nest treatment with herbs on ectoparasites and body condition of nestlings.

Nest fumigation behavior involves the incorporation of fresh green plant fragments that contain ectoparasite-repellent volatile compounds into birds' nests. This behavior is relatively rare among bird species, and there is ongoing debate about whether it benefits parental breeding success. In this study, we experimentally tested whether the inclusion of aromatic-herbal plant fragments in the nests of great tits Parus major affects the physiological condition of nestlings, as indicated by blood levels of hematocrit, hemoglobin, glucose, and body condition indices, such as weight and wing length. We divided the nests into 2 groups, adding aromatic herbs to the test group's nests and non-aromatic plants to the control group. After the nestlings fledged, all nest materials were collected to extract, identify, and count arthropod ectoparasites. Nestlings in nests supplemented with aromatic plant fragments had elevated levels of hematocrit and hemoglobin, indicating improved physiological condition compared to the control group. Ectoparasites were present in both groups, although ticks (Ixodidae) occurred less frequently in nests with aromatic plants. The experimental treatment did not affect fledging success. Further experimental studies are needed to explore the effects of incorporating aromatic plant fragments into tit nests within the frameworks of both the nest protection hypothesis and the drug hypothesis.

Effects of acoustic signals on the breeding success of the tropical weaver bird, ploceus philippinus (l)

In the animal kingdom, vocal communication is the most important way of conveying information among individuals of the same species. The avian communication system is one of the most complex communication systems, not only for claiming territory, lookingfor food, alarming against predators, and calling their young ones but also playing a major role in modulating breeding activities. The study was conducted on the Baya weaver bird, a colonial breeder, to explore the collective efficacy and effects of vocal signals on breeding individuals which has a greater impact on their breeding success. The weaver bird is a seasonal breeder, keeping in flocks and breeding in colonies. It exhibits sexual bimatuarism and dichromatism. The adult male weaver weaves the nest and performs spectacular courtship displays like wing quivering, nest pointing, nest greeting, chasing in and around the nesting colony, and delivering songs. The Oscillograph analysis of different call notes shows that certain vocal signals are delivered only during breeding season suggesting that these songs have a modulating effect on the breeding success.. KEYWORDS :Acoustic signals, Vocal communication, Breeding success, colonial breeders

Climate Change Impacts Pair-Bond Dynamics in a Long-Lived Monogamous Species.

Climate change can influence populations of monogamous species by affecting pair-bond dynamics. This study examined the impact of climate on widowhood and divorce, and the subsequent effects on individual vital rates and life-history outcomes over 54 years in a snow petrel (Pagodroma nivea) population. We found that environmental conditions can affect pair-bond dynamics both directly and indirectly. Divorce was adaptive, occurring more frequently after breeding failure and leading to improved breeding success. Divorce probabilities also increased under severe climatic conditions, regardless of prior breeding success, supporting the 'Habitat-mediated' mechanisms. Overall, pair-bond disruptions reduced subsequent vital rates and lifetime outcomes. Climate forecasts from an Atmosphere-Ocean General Circulation Model projected increased male widowhood rates due to decreased sea ice negatively affecting female survival, despite considerable uncertainty. These findings highlight the importance of environmentally induced changes in demographic and pair-bond disruption rates as crucial factors shaping demographic responses to climate change.

A Review of Studies on the Breeding, Reproduction and Fry Rearing of Largemouth Bass (Micropterus nigricans) in China

ABSTRACTMany countries and regions around the world have been adversely affected by the invasive spread of the largemouth bass (Micropterus nigricans). The breeding practices developed in China can serve as a reference for these regions to manage this species scientifically while providing high‐quality protein for human consumption. As its introduction from Taiwan in 1983, the largemouth bass has become one of the most significant high‐quality freshwater farmed fish in mainland China. The country has developed new varieties that exhibit faster growth rates and enhanced adaptability to artificial compound feed, leading to widespread aquaculture across the nation. This article systematically reviews the technological advancements in the introduction, breeding, reproduction and rearing of fry and fingerlings of largemouth bass in China over the last 40 years. After summarizing the progress in general breeding as well as fry and fingerling rearing technologies, we analyse three successful early breeding and out‐of‐season breeding modes developed in China. The advancement of innovative and practical breeding and seedling technologies has addressed the challenges of natural breeding in regions with relatively low temperatures, where it is not feasible to raise local fry to a marketable size for consumption within the same year. This progress significantly enhances largemouth bass aquaculture in China.

Comparative Analysis of Gut Microbiota Between Wild and Captive Guizhou Snub-Nosed Monkey (Rhinopithecusbrelichi).

Maintaining a healthy status is crucial for the successful captive breeding of critically endangered Rhinopithecus brelichi, it is conducive to ex situ conservation of this species and rejuvenation of its population. However, changes in the feeding environment and food can affect the composition and function of the gut microbiota in R. brelichi, ultimately impacting its health and adaptation. Herein, 16S rRNA gene sequencing was employed to determine the gut microbiota composition and functional variations between wild and captive R. brelichi populations. The results showed that the captive group had higher alpha diversity than the wild group, and significant differences were observed in their beta diversity. Captive and wild R. brelichi showed similar microbiota at the phylum level, which mainly comprised Firmicutes, Bacteroidota, and Spirochaetota, but captivity reduced the Firmicutes/Bacteroides ratio. Differential abundance analysis revealed that the relative abundance of microbiota related to cellulose degradation, such as Prevotellaceae_UCG_001, Christensenellaceae_R_7_group, Ruminococcus, and Fibrobacter, differed significantly between the two groups. Furthermore, the potential pathogens Acinetobacter and Treponema were significantly abundant in wild and captive groups, respectively. Functional predictions demonstrated that the most significant functional pathways at the second level between captive and wild monkeys were carbohydrate, amino acid, and lipid metabolisms. The captive monkeys exhibited higher digestive capacity and endocrine regulation as well as a higher risk of infectious diseases than wild monkeys. These findings can serve as a valuable theoretical basis for promoting the healthy breeding of R. brelichi and as a guide for future evaluation of the health of wild and captive monkeys.

Plastic Behaviour Buffers Climate Variability in the Wandering Albatross.

Climate change has marked effects on global weather patterns and oceanic systems, impacting animal behaviour and fitness in potentially profound ways. Despite this, we lack detailed information about species' responses to climatic variation. Using an 11-year tracking dataset of over 300 individual birds, we explore the consequences of variation in the southern annular mode (SAM) and southern oscillation index (SOI) for individual behaviour and fitness in wandering albatrosses Diomedea exulans breeding in the Southern Indian Ocean. Our results reveal distinct responses between males and females to climatic variation that align with the impacts of each climatic index on the distinct foraging ranges of each sex. In positive SAM phases, linked to poorer foraging conditions in female ranges and better conditions in male ranges, females exhibited behaviour consistent with reduced foraging success: that is, fewer prey capture attempts and more movement between feeding patches. Males, on the other hand, showed no behavioural change. During positive SOI phases, associated with good foraging conditions in both male and female foraging ranges, both sexes showed evidence of more successful foraging, with birds engaging in more search behaviour, and taking shorter trips with fewer prey capture attempts, together indicating increased food intake per unit time. We found limited evidence for a role of individual variation, as measured through differences in personality, suggesting that plastic responses to climate are sufficiently important so as to obscure inter-individual variation. Supporting this was the finding that individual breeding success was unaffected by climatic variation, suggesting that plastic foraging behaviour allows albatrosses to mitigate climate impacts and maintain reproductive output.

Breeding Success of Eurasian Cranes (Grus grus, Gruiformes, Aves) in Conditions of Changing Environment: Effect of Climatic and Hydrometeorological Trends

Breeding Success of Eurasian Cranes (Grus grus, Gruiformes, Aves) in Conditions of Changing Environment: Effect of Climatic and Hydrometeorological Trends

Metabolic marker-assisted genomic prediction improves hybrid breeding

Hybrid breeding is widely acknowledged as the most effective method for increasing crop yield, particularly in maize and rice. However, a major challenge in hybrid breeding is selecting desirable combinations from a vast pool of potential crosses. Genomic selection (GS) has emerged as a powerful tool to tackle this challenge, but its success in practical breeding depends on prediction accuracy. Several strategies have been explored to enhance the prediction accuracy for complex traits, such as incorporating functional markers and multi-omics data. Metabolome-wide association studies (MWAS) help identify metabolites closely linked to phenotype, known as metabolic markers. However, the use of preselected metabolic markers from parental lines to predict hybrid performance has not yet been explored. In this study, we developed a novel approach called metabolic marker-assisted genomic prediction (MM_GP) that incorporates significant metabolites identified from MWAS into GS models to improve the accuracy of genomic hybrid prediction. In maize and rice hybrid populations, MM_GP outperformed GP for all traits, regardless of the methods used (GBLUP or XGBoost). On average, MM_GP yielded 4.6% and 13.6% higher predictive abilities compared to GP in maize and rice, respectively. Additionally, MM_GP could match or even surpass the predictive ability of M_GP (integrated genomic-metabolomic prediction) for most traits. Notably, integrating only six metabolic markers significantly related to multiple traits resulted in a 5.0% and 3.1% higher average predictive ability than GP and M_GP in maize, respectively. With the advancement of high-throughput metabolomics technologies and prediction models, this approach holds great promise to revolutionize genomic hybrid breeding by enhancing its accuracy and efficiency.

Life history, population dynamics and impacts of cat predation on an endemic gadfly petrel in Cabo Verde

Insular fauna often suffers significant predation from invasive mammals, yet robust evidence of their impact from rigorous demographic analysis remains scarce. We aimed to understand the life history and population dynamics of the elusive Cape Verde petrel Pterodroma feae, an endemic seabird of the Cabo Verde archipelago, which is severely predated by cats. We analysed capture-mark-recapture data from birds mist-netted in a courtship area in 2007-2021 and monitored their nests between 2012 and 2021 on Fogo Island. Across all islands where this species breeds, we recorded cat predation rates and made additional captures of petrels in courtship areas. Demographic analysis revealed an 8.8% annual population decline of Cape Verde petrels, primarily driven by a 14.7% surplus mortality among breeders from threats in breeding areas, likely tied to the annual cat predation rate of at least 4% observed in monitored nests. Immature males exhibited lower survival rates, likely due to their increased vulnerability while seeking initial nest sites. The limited connectivity detected among and within islands, along with strong nest-site and mate fidelity rates, highlight the urgency of preventing local extinctions, which would be challenging to reverse. This study emphasizes the unsustainability of cat predation rates and the insufficiency of enhancing breeding success to counter the population decline, and it provides compelling evidence of a concerning decline of the Cape Verde petrel, primarily attributable to cat predation. Moreover, it emphasizes the significance of long-term demographic studies to understand the impact of invasive species on endangered populations.

Conspecific breeding success does not guide nest-site choice for the next year in three leaf warbler species (Passeriformes, Phylloscopidae)

Conspecific breeding success does not guide nest-site choice for the next year in three leaf warbler species (Passeriformes, Phylloscopidae)

SimpleMating: R-package for prediction and optimization of breeding crosses using genomic selection.

Selecting parents and crosses is a critical step for a successful breeding program. The ability to design crosses with high means that will maintain genetic variation in the population is the goal for long-term applications. Herein, we describe a new computational package for mate allocation in a breeding program. SimpleMating is a flexible and open-source R package originally designed to predict and optimize breeding crosses in crops with different reproductive systems and breeding designs. Divided into modules, SimpleMating first estimates the cross performance (criterion), such as mid-parental value, cross total genetic value, and/or usefulness of a set of crosses. The second module implements an optimization algorithm to maximize a target criterion while minimizing next-generation inbreeding. The software is flexible, enabling users to specify the desired number of crosses, set maximum and minimum crosses per parent, and define the maximum allowable parent relationship for creating crosses. As an outcome, SimpleMating generates a mating plan from the target parental population using single or multi-trait criteria. For example, we implemented and tested SimpleMating in a simulated maize breeding program obtained through stochastic simulations. The crosses designed via SimpleMating showed a large genetic mean over time (up to 22% more genetic gain than conventional genomic selection programs, with lesser loss of genetic diversity over time), supporting the use of this tool, as well as the use of data-driven decisions in breeding programs.

Egg Production, Egg Development, and Mortality of Zoo-Bred Ozark Hellbenders (Cryptobranchus alleganiensis bishopi).

Populations of Ozark hellbenders (Cryptobranchus alleganiensis bishopi, Grobman 1943) in Missouri and Arkansas are federally listed as endangered. The Saint Louis Zoo WildCare Institute's Ron and Karen Goellner Center for Hellbender Conservation, in collaboration with the Missouri Department of Conservation and US Fish and Wildlife Service, has developed a sustainable conservation breeding and head-starting program, a priority for species recovery. Using 9 years of program data, we examined various egg production, egg development, and mortality responses of Zoo-bred Ozark hellbenders. Our results identified river of origin and breeding location as important predictors of egg production responses including average breeding female total lengths as well as brooding male clutch size, total egg count, and the estimated number of female clutches, respectively. We found that breeding group generation was a significant predictor of Zoo-bred hellbender egg development responses with hellbenders from the first breeding group generation ovipositing later and producing eggs that hatch later and develop longer than hellbenders from the second-generation breeding group. These responses are consistent with females from the first breeding group generation being larger at the time of reproduction. Breeding group generation was also a significant predictor of proportional egg and total mortality, while the proportion of hatchling mortality was best predicted by breeding location, and the proportion of larval mortality was best predicted by river of origin. Ultimately, our results provide baseline metrics for the program and identify areas for further inquiry to maximize the success of future conservation breeding and head-starting efforts at the Zoo.

Characterization of Citrus × Poncirus Embryo Rescued Hybrids as Rootstock Candidate using Morphological Markers

Generally, there are both nucellar and zygotic embryos in the citrus seeds after cross breeding. Since genetic variations are very important for the success of plant breeding, morphological traits of individuals are evaluated to identify diversity. The present study aimed to characterize of citrus hybrids for new rootstock genotypes based on their morphological characters at the seedling stage. A total of 335 putative interspecific hybrids, derived from 3 crosses [Common sour orange (Citrus aurantium L.) × Troyer citrange (Citrus sinensis L. × Poncirus trifoliata L.), Common mandarin (Citrus deliciosa Ten.) × Troyer citrange (Citrus sinensis L. × Poncirus trifoliata L.) and King mandarin (Citrus nobilis L.) × Carrizo citrange (Citrus sinensis L. × Poncirus trifoliata L.)], were observed by their plant morphology. The eight qualitative and five quantitative characteristics of hybrid plants such as seedling growth, leaf and thorniness characteristics were evaluated. The average plant height of the population was found between 70.2 cm and 133.2 cm. The average stem diameter varied between 5.9 mm and 8.0 mm. Hybrid seedlings were separated on the basis of dominant trifoliate leaf marker. There was wide diversity among the accessions with respect to quantitative leaf characters. In terms of leaf division, 268 genotypes have bifoliate and 67 were trifoliate in all combinations, and many intermediate forms were also observed. In addition 66 of the genotypes were thornless while 269 of the genotypes were thorny. The genotype No. 4, has been assessed as triploid, from Common mandarin × Troyer citrange combination, has the longest and dense spines. Morphological markers data were analyzed by clustering method to compare similarities of hybrids. The dissimilarity index was observed between 0.004 and 17.318 within three hybridization combinations. The hybrids obtained at 110 days after pollination were more distant relative to each other in all hybridization combination.

Unexpected soundscape response to insecticide application in oak forests.

Rachel Carson's warning of a silent spring directed attention to unwanted side effects of pesticide application. Though her work led to policies restricting insecticide use, various insecticides currently in use affect nontarget organisms and may contribute to population declines. The insecticide tebufenozide is used to control defoliating Lepidoptera in oak forests harboring rich insect faunas. Over 3years, we tested the effect of its aerial application on bird populations with autonomous sound recorders in a large, replicated, full factorial field experiment during a spongy moth (Lymantria dispar) outbreak. The soundscape analysis combined automated aggregation of recordings into sound indices with species identification by experts. After pesticide application in the year of the outbreak, acoustic complexity in early summer was significantly reduced. The soundscape analysis showed that the reduction was not related to birds, but instead to the large reduction in caterpillar feeding and frass dropping. Effects on the vocal activity of birds were smaller than originally expected from a related study demonstrating tebufenozide's negative effect on bird breeding success. The legacy of the pesticide treatment, in terms of soundscape variation, was not present in the second year when the outbreak had ended. Our results showed a dimension of insecticide-induced acoustic variation not immediately accessible to the human ear. It also illustrated how a multifaceted soundscape analysis can be used as a generic approach to quantify the impact of anthropogenic stressors in novel ways by providing an example of remote and continuous sound monitoring not possible in conventional field surveys.