Breeding Opportunities Research Articles

On the Future Perspectives of Some Medicinal Plants within Lamiaceae Botanic Family Regarding Their Comprehensive Properties and Resistance against Biotic and Abiotic Stresses.

Lamiaceae is one of the largest botanical families, encompassing over 6000 species that include a variety of aromatic and medicinal spices. The current study is focused on three plants within this botanical family: basil (Ocimum basilicum L.), thyme (Thymus vulgaris L.), and summer savory (Satureja hortensis L.). These three species contain primary and secondary metabolites such as phenolic and flavonoid compounds, fatty acids, antioxidants, and essential oils and have traditionally been used for flavoring, food preservation, and medicinal purposes. The goal of this study is to provide an overview of the nutraceutical, therapeutic, antioxidant, and antibacterial key features of these three aromatics to explore new breeding challenges and opportunities for varietal development. In this context, a literature search has been performed to describe the phytochemical profile of both primary and secondary metabolites and their pharmacological uses, as well as to further explore accession availability in the medicine industry and also to emphasize their bioactive roles in plant ecology and biotic and abiotic stress adaptability. The aim of this review is to explore future perspectives on the development of new, highly valuable basil, summer savory, and thyme cultivars. The findings of the current review emphasize the importance of identifying the key compounds and genes involved in stress resistance that can also provide valuable insights for further improvement of these important medicinal plants.

Genome-Wide Identification of the KNOX Gene Family in Japanese Apricot (Prunus mume Sieb. et Zucc.) and Functional Characterization of PmKNAT2 Genes.

The Knotted1-like Homeobox gene is crucial for plant morphological development and growth. Physicochemical characteristics, phylogenetic relationships, chromosomal localization, cis-acting elements, and tissue-specific expression patterns of the 11 PmKNOX genes found in the Japanese apricot genome in this study were examined. Proteins of 11 PmKNOX were soluble proteins with isoelectric points between 4.29 and 6.53, molecular masses between 15.732 and 44.011 kDa, and amino acid counts between 140 and 430. The identified PmKNOX gene family was split into three subfamilies by jointly constructing the phylogenetic tree of KNOX proteins in Japanese apricot and Arabidopsis thaliana. Combined outcomes of the analyzed conserved motifs and gene structures of the 11 PmKNOX genes from the same subfamily displayed comparable gene structure and motif patterns. The 11 PmKNOX members were distributed across six chromosomes, while two sets of PmKNOX genes were found to be collinear. Analysis of the 2000 bp promoter upstream of the coding region of the PmKNOX gene revealed that most PmKNOX genes might be involved in the physiological metabolism, growth and development processes of plants. The PmKNOX gene expression profile revealed that these genes were expressed at varying levels in different tissues, and most of them were linked to the meristems of leaf and flower buds, suggesting that PmKNOX may be involved in plants' apical meristems. In Arabidopsis thaliana, functional validation of PmKNAT2a and PmKNAT2b revealed that these two genes might be involved in regulating leaf and stem development. In addition to laying the groundwork for future research on the function of these genes, understanding the evolutionary relationships between members of the PmKNOX gene family provides opportunities for future breeding in Japanese apricots.

An overview of genome engineering in plants, including its scope, technologies, progress and grand challenges.

Genome editing is a useful, adaptable, and favored technique for both functional genomics and crop enhancement. Over the years, rapidly evolving genome editing technologies, including clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas), transcription activator-like effector nucleases (TALENs), and zinc finger nucleases (ZFNs), have shown broad application prospects in gene function research and improvement of critical agronomic traits in many crops. These technologies have also opened up opportunities for plant breeding. These techniques provide excellent chances for the quick modification of crops and the advancement of plant science in the future. The current review describes various genome editing techniques and how they function, particularly CRISPR/Cas9 systems, which can contribute significantly to the most accurate characterization of genomic rearrangement and plant gene functions as well as the enhancement of critical traits in field crops. To accelerate the use of gene-editing technologies for crop enhancement, the speed editing strategy of gene-family members was designed. As it permits genome editing in numerous biological systems, the CRISPR technology provides a valuable edge in this regard that particularly captures the attention of scientists.

Contributions of plant breeding to soil carbon storage: Retrospect and prospects

AbstractThere is interest in harnessing cropland C storage potential at a large scale to mitigate climate change and improve land productivity. While the effects of soil management practices on C storage have been studied extensively, opportunities to select for C sequestration traits in crop plants remain largely unexplored. This review describes how genetic improvement of major US crops may have altered soil C stocks historically and identifies potential opportunities for plant breeding to increase cropland C stocks. Through quantitative literature review, we find that breeding has led to an increase in aboveground residue C inputs to the soil for corn (Zea maysL.) and soybeans (Glycine max(L.) Merr) and a decrease in aboveground residue C inputs for wheat (Triticum aestivumL. andTriticum turgidumL.). Breeding has largely not altered the root:shoot ratio of these crops. Given that there is limited potential for further major improvements in harvest index, breeding for high grain yields may necessitate increasing aboveground biomass and residue production in the future. Crop root traits and residue quality may influence the stabilization of crop‐derived C in soil, but there is uncertainty regarding historical changes in these traits due to breeding, the magnitude of their effect on soil organic C stocks, and tradeoffs or synergies with breeding for high yield. Nevertheless, root traits such as suberin content, rhizodeposition, mycorrhizal association, and depth emerge as potential targets for more efficient C stabilization. There is also a large opportunity for plant breeding to enhance the performance of cover crops, double crops, perennial grains, and perennial groundcovers, which can increase annual C inputs to the soil by occupying fallow periods. Our review reveals that there are many opportunities for plant genetic improvement to fix more C in cropping systems and enhance its stabilization in the soil to meet the goals of sustainable intensification and cropland C capture.

Landscape characteristics and predation risk influence spatial variation in auditory courtship of an upland game bird

ContextNumerous wildlife species use a polygynous mating system, where males use auditory courtship behaviors to secure breeding opportunities. The acoustic adaptation hypothesis, risk reward, and landscape of fear theories suggest spatial variation in male auditory courtship will be influenced by areas in landscapes where sound transmission is increased, and predation risk is reduced. However, it is often unclear what landscape features drive spatial variation in courtship behaviors.ObjectivesWe quantified the influence of predation risk, land cover type, and resource selection on spatial trends in the auditory courtship behavior (gobbling activity) of Eastern wild turkeys (Meleagris gallopavo silvestris).MethodsWe used 53,025 gobbles coupled with GPS locations from 111 turkeys and 36 coyotes (Canis latrans), and distance metrics associated with hunter activity and land cover type, to investigate influences of predation risk, resource selection, and land cover type on spatial variation in gobbling activity in Georgia, USA.ResultsDistance to public access during hunting was the most influential predictor of gobbling activity, wherein the expected number of daily gobbles increased by 40% for every 500 m farther from public access. Daily gobbles decreased by 22% for every 500 m farther away from private property during hunting. We failed to find significant effects of land cover type and coyote use but found limited evidence that areas with increased predicted probability of turkey use was associated with increased gobbling.ConclusionsPredation risk associated with increased anthropogenic disturbance had the greatest influence on gobbling activity. Our findings suggest that altering hunter access by closing roads to vehicle use, reducing hunter activity, or creating refuge areas on the landscape could positively influence gobbling activity.

Breeding phase and outcome determine space use in European rollers Coracias garrulus prior to migration.

The breeding period is a demanding and time-constrained phase for migratory bird species. Breeding outcome and duration can interact with the extent and duration of post-breeding movements, resulting in individual differences in space use ultimately influencing later stages of the annual cycle. We present space-use and home range estimates during the breeding season for 21 European rollers Coracias garrulus tracked between 2018 and 2022, in Italy and Croatia. Using high-resolution spatial GPS data coupled with regular nest-box monitoring, we analyzed differences in space use during the incubation/nestling period versus post-breeding period prior to migration, accounting for the breeding outcome (successful vs. failure). We found that adult movements were strongly reduced during the first phase, whereas increased in the post-breeding phase, especially for failed breeders. Successful breeders remained in the surroundings of the nest site, whereas unsuccessful ones tended to abandon the nest and visit distant areas (up to 500 km) for long periods (60.5 ± 6.2 days). Breeding outcome did not influence the departure date of autumn migration, suggesting that failed breeders used this period for exploratory movements but not for advancing the onset of migration. Such exploratory movements may be functional to prospect and inform settlement decisions in failed breeders in search of new breeding opportunities and may be particularly important in migratory species, which generally have a limited period to gather information prior to autumn migration. The study demonstrates the need to investigate seasonal movements in different populations and the potential importance of prospecting post-breeding movements for long-distance migratory species.

Engineered biocontainable RNA virus vectors for non-transgenic genome editing across crop species and genotypes

CRISPR/Cas genome-editing tools provide unprecedented opportunities for basic plant biology research and crop breeding. However, the lack of robust delivery methods has limited the widespread adoption of these revolutionary technologies in plant science. Here, we report an efficient, non-transgenic CRISPR/Cas delivery platform based on the engineered tomato spotted wilt virus (TSWV), an RNA virus with a host range of over 1000 plant species. We eliminated viral elements essential for insect transmission to liberate genome space for accommodating large genetic cargoes without sacrificing the ability to infect plant hosts. The resulting non-insect-transmissible viral vectors enabled effective and stable in planta delivery of Cas12a and Cas9 nucleases as well as adenine and cytosine base editors. In systemically infected plant tissues, the deconstructed TSWV-derived vectors induced efficient somatic gene mutations and base conversions in multiple crop species with little genotype dependency. Plants with heritable, bi-allelic mutations could be readily regenerated by culturing the virus-infected tissues in vitro without antibiotic selection. Moreover, we showed that antiviral treatment with ribavirin during tissue culture cleared the viral vectors in 100% of regenerated plants and further augmented the recovery of heritable mutations. Because many plants are recalcitrant to stable transformation, the viral delivery system developed in this work provides a promising tool to overcome gene delivery bottlenecks for genome editing in various crop species and elite varieties.

Rust (Uromyces viciae-fabae Pers. de-Bary) of Pea (Pisum sativum L.): Present Status and Future Resistance Breeding Opportunities.

Uromyces viciae-fabae Pers. de-Bary is an important fungal pathogen causing rust in peas (Pisum sativum L.). It is reported in mild to severe forms from different parts of the world where the pea is grown. Host specificity has been indicated in this pathogen in the field but has not yet been established under controlled conditions. The uredinial states of U. viciae-fabae are infective under temperate and tropical conditions. Aeciospores are infective in the Indian subcontinent. The genetics of rust resistance was reported qualitatively. However, non-hypersensitive resistance responses and more recent studies emphasized the quantitative nature of pea rust resistance. Partial resistance/slow rusting had been described as a durable resistance in peas. Such resistance is of the pre-haustorial type and expressed as longer incubation and latent period, poor infection efficiency, a smaller number of aecial cups/pustules, and lower units of AUDPC (Area Under Disease Progress Curve). Screening techniques dealing with slow rusting should consider growth stages and environment, as both have a significant influence on the disease scores. Our knowledge about the genetics of rust resistance is increasing, and now molecular markers linked with gene/QTLs (Quantitative Trait Loci) of rust resistance have been identified in peas. The mapping efforts conducted in peas came out with some potent markers associated with rust resistance, but they must be validated under multi-location trails before use in the marker-assisted selection of rust resistance in pea breeding programs.

Genetic diversity and population structure assessment of Western Canadian barley cooperative trials.

Studying the population structure and genetic diversity of historical datasets is a proposed use for association analysis. This is particularly important when the dataset contains traits that are time-consuming or costly to measure. A set of 96 elite barley genotypes, developed from eight breeding programs of the Western Canadian Cooperative Trials were used in the current study. Genetic diversity, allelic variation, and linkage disequilibrium (LD) were investigated using 5063 high-quality SNP markers via the Illumina 9K Barley Infinium iSelect SNP assay. The distribution of SNPs markers across the barley genome ranged from 449 markers on chromosome 1H to 1111 markers on chromosome 5H. The average polymorphism information content (PIC) per locus was 0.275 and ranged from 0.094 to 0.375. Bayesian clustering in STRUCTURE and principal coordinate analysis revealed that the populations are differentiated primarily due to the different breeding program origins and ear-row type into five subpopulations. Analysis of molecular variance based on PhiPT values suggested that high values of genetic diversity were observed within populations and accounted for 90% of the total variance. Subpopulation 5 exhibited the most diversity with the highest values of the diversity indices, which represent the breeding program gene pool of AFC, AAFRD, AU, and BARI. With increasing genetic distance, the LD values, expressed as r2, declined to below the critical r2 = 0.18 after 3.91 cM, and the same pattern was observed on each chromosome. Our results identified an important pattern of genetic diversity among the Canadian barley panel that was proposed to be representative of target breeding programs and may have important implications for association mapping in the future. This highlight, that efforts to identify novel variability underlying this diversity may present practical breeding opportunities to develop new barley genotypes.

Wheat end-use quality: State of art, genetics, genomics-assisted improvement, future challenges, and opportunities.

Wheat is the most important source of food, feed, and nutrition for humans and livestock around the world. The expanding population has increasing demands for various wheat products with different quality attributes requiring the development of wheat cultivars that fulfills specific demands of end-users including millers and bakers in the international market. Therefore, wheat breeding programs continually strive to meet these quality standards by screening their improved breeding lines every year. However, the direct measurement of various end-use quality traits such as milling and baking qualities requires a large quantity of grain, traits-specific expensive instruments, time, and an expert workforce which limits the screening process. With the advancement of sequencing technologies, the study of the entire plant genome is possible, and genetic mapping techniques such as quantitative trait locus mapping and genome-wide association studies have enabled researchers to identify loci/genes associated with various end-use quality traits in wheat. Modern breeding techniques such as marker-assisted selection and genomic selection allow the utilization of these genomic resources for the prediction of quality attributes with high accuracy and efficiency which speeds up crop improvement and cultivar development endeavors. In addition, the candidate gene approach through functional as well as comparative genomics has facilitated the translation of the genomic information from several crop species including wild relatives to wheat. This review discusses the various end-use quality traits of wheat, their genetic control mechanisms, the use of genetics and genomics approaches for their improvement, and future challenges and opportunities for wheat breeding.

Investigation of Herd Structure and Breeding Practices in Sheep Farms in Elazig Province

Bu araştırmanın amacı, Elazığ ilindeki işletmelerde koyun varlığının, sürü yapısının ve temel yetiştiricilik faaliyetlerinin durumunu belirlemektir. Araştırmada 167 adet koyunculuk işletmesinde Mayıs-Aralık 2020 tarihlerinde yetiştiricilerle yüz yüze anket gerçekleştirilmiştir. Çalışmada, işletmelerin %61.inin 7-17 baş koça sahip olması, %83.9’unda dişi tokluların damızlıkta ilk kez 12-17 aylıkken, %100’ünde erkek tokluların ilk kez 1.5-2 yaşındayken aşımda kullanılması, %71.7’sinin damızlıkları kendi işletmesinden sağlaması, %83.7’sinin koçları sürüde kızgınlık süresince tutması, %73.1’inin yeme tuz ve mineral ilavesi yapması, %77.7’sinin kadın ve erkek birlikte sağım yapması, %78.2’sinin sütü peynir yapması olumlu ve yeterli olarak belirlenmiştir. Bunun yanında, işletmelerin ancak %66.1’sında kayıtların tutulması, %90.4’ünde serbest aşım metodunun tercih edilmesi, %89.9’unda kuzulara doğal büyütme uygulanması, yetiştiricilerin %55.7’sinin koyunlarına kaba yem olarak sadece saman vermesi, %44.6’sının ek yemleme yapmaması, %78.4’ünün yemi fabrikalardan temin etmesi, %97.6’sının sağımı elle gerçekleştirmesi ve %89.3’ünün kırkımı makasla yapması ise mevcut olumsuzluklar ve yetersizlikler olarak saptanmıştır. Sonuç olarak, koyun sayısı ve yetiştiricilik imkânları bakımından önemli bir potansiyeli olan Elazığ ilinde, işletmelerdeki yeterli-olumlu yetiştiricilik faaliyetlerinin sürdürülmesi yanında, belirlenmiş yetersizliklerin ve olumsuzlukların giderilmesiyle gelir ve ekonomik kazancın artırılabileceği kanaatine varılmıştır.

Effects of forest management on the spatial distribution of the willow tit (Poecile montanus)

Modification, fragmentation and loss of boreal forest habitats have been intensive during the last century due to forestry practises and land use. This has been related to population declines of many forest species, yet the mechanisms affecting on the background are largely unknown. The willow tit, a primary cavity-nesting species that was once the 4th most common bird species in Finland is nowadays endangered. Earlier findings suggest that the willow tit population is affected by the reduction of nesting sites, decaying snags in forests and the loss of mature forests which contain the food storages during the winter. In this study we are searching for the mechanisms how the forest management methods could explain the decline of the willow tit population. We used long-term breeding data of the willow tit nesting sites from 1990 to 2020 collected in a study area in northern Finland to analyse if forest management affected nearest neighbour distances and natal dispersal and breeding dispersal distances. We used Geographic Information System (GIS) methods to combine the ecological breeding data to accurate spatial forest management and habitat quality data. The data was analysed with linear mixed models. We found that clear-cuttings affected the willow tit dispersal and neighbouring nest distances more than thinnings. Both clear-cuttings and thinnings increased the nearest neighbour distances. The natal and breeding dispersal distances were lengthened by increasing proportions of clear-cuttings. The habitat loss caused by clear-cuttings and the decrease in habitat quality caused by thinnings has had a major role in the decline of the willow tit population. The forest management actions were estimated to explain about 65 % of the willow tit breeding density decrease in the study area. The effects of forest management were witnessed in a cumulative 0–30-year period meaning that forest management causes long-term habitat degradation and loss. Availability of deciduous snags in the forests can compensate the habitat loss to some extent by providing better breeding opportunities. As the effects of clear-cutting were more severe to the willow tit than thinning, we recommend using other forest management methods than clear-cutting as the main management method.

Host plant status and damage threshold of spinach (Spinacia oleracea) for the temperate root-knot nematode Meloidogyne chitwoodi

Summary Problems with plant-parasitic nematodes remain a major challenge in most field vegetable crops worldwide. In agricultural fields in Belgium, these problems have increased in recent years. A major problem is the quarantine root-knot nematode Meloidogyne chitwoodi. The host plant status of the most commonly grown cultivars of spinach (Spinacia oleracea) and the damage threshold for M. chitwoodi were determined in a climate-controlled glasshouse and in a naturally infested field. The yield data with the final population densities were fitted to Seinhorst’s yield and population dynamic models, respectively. The damage threshold values (T) for the relative fresh weight yield were 0.14, 1.08, 11.53 J2 (100 cm3 soil)−1, minimum yield (m) of 0.84, 0.64, 0.52 and maximum yield () of 12.51, 12.44 and 9.60 for ‘Gnu’, ‘Meerkat’ and ‘Whale’ spinach cultivars, respectively. The maximum multiplication rates (a) were 3.81, 2.38 and 2.72, whilst the maximum population densities (M) were 563, 916, and 922 J2 (100 cm3 soil)−1 for ‘Gnu’, ‘Meerkat’ and ‘Whale’, respectively. Meloidogyne chitwoodi had an impact on the spinach yield. The higher the nematode density the lower the yield and vice versa. The tested cultivars were all hosts for M. chitwoodi but differences between cultivars occurred. ‘Kolibri’ and ‘Rhino’ were tested as the least sensitive cultivars for M. chitwoodi during the host screening test and bring opportunities for resistance breeding. This is the first report of spinach as a host for M. chitwoodi.

Morphological, Cytological, and Molecular Comparison between Diploid and Induced Autotetraploids of Callisia fragrans (Lindl.) Woodson

The objective of the current study was to assess the efficiency of oryzalin in inducing polyploids in Callisia fragrans (Lindl.) Woodson by in vitro polyploidization. Shoot tips were subjected to Murashige and Skoog (MS) medium containing oryzalin at concentrations 1, 5, and 10 μM for 4 and 8 weeks. Further, the ploidy levels of the plants were confirmed using flow cytometry and chromosome counting. Among all treatments, six tetraploid plants (2n = 4x = 24) were obtained after 8 weeks in MS medium containing 5 μM oryzalin. Upon ex vitro transfer, tetraploid plants were morphologically distinct compared to diploid plants. The size of the leaf and flower increased significantly and nearly doubled when compared to the mother diploid plant. Further, inductively coupled plasma–optical emission spectrometry showed that tetraploid plants exhibited significantly higher sodium, iron, and calcium content, and the potassium content was increased by 100%. Molecular analysis utilizing iPBS and CDDP markers was tested for the first time in C. fragrans to assess the variation between tetraploid and diploid genotypes. Both the markers generated three major clusters, indicating a clear distinction between diploid, tetraploid, and the mixoploid genotypes. In conclusion, in vitro polyploidization using oryzalin could effectively induce polyploids in this and related species. Additionally, the results obtained in this study will provide a basis for future breeding opportunities in this species.

Promoting Sustainable Utilization and Genetic Improvement of Indonesian Local Beef Cattle Breeds: A Review

This paper reviews the literature relevant to the breeding of cattle grazed in tropical environments and particularly Indonesia. The aim is to identify new breeding opportunities for cattle owned by Indonesia’s smallholder farmers, whilst also conserving unique local cattle beef breeds. Crossbreeding has been practiced extensively in Indonesia, but to date there have been no well-designed programs, resulting in many mixed-breed animals and no ability to determine their genetic composition, productive capabilities or adaptation to environmental stressors. An example of within-breed selection of Bali cattle based on measured live weight has similarly disregarded other productive and adaptive traits. It is unlikely that smallholder farmers could manage effective crossbreeding programs due to the complexities of management required. However, a tropically adapted composite breed(s) could perhaps be developed and improved using within-breed selection. Establishing reference population(s) of local breeds or composites and using within-breed selection to genetically improve those herds may be feasible, particularly if international collaborations can be established to allow data-pooling across countries. The use of genomic information and a strong focus on all economically important traits in practical breeding objectives is critical to enable genetic improvement and conservation of unique Indonesian cattle breeds.

Applications of Artificial Intelligence in Climate-Resilient Smart-Crop Breeding.

Recently, Artificial intelligence (AI) has emerged as a revolutionary field, providing a great opportunity in shaping modern crop breeding, and is extensively used indoors for plant science. Advances in crop phenomics, enviromics, together with the other “omics” approaches are paving ways for elucidating the detailed complex biological mechanisms that motivate crop functions in response to environmental trepidations. These “omics” approaches have provided plant researchers with precise tools to evaluate the important agronomic traits for larger-sized germplasm at a reduced time interval in the early growth stages. However, the big data and the complex relationships within impede the understanding of the complex mechanisms behind genes driving the agronomic-trait formations. AI brings huge computational power and many new tools and strategies for future breeding. The present review will encompass how applications of AI technology, utilized for current breeding practice, assist to solve the problem in high-throughput phenotyping and gene functional analysis, and how advances in AI technologies bring new opportunities for future breeding, to make envirotyping data widely utilized in breeding. Furthermore, in the current breeding methods, linking genotype to phenotype remains a massive challenge and impedes the optimal application of high-throughput field phenotyping, genomics, and enviromics. In this review, we elaborate on how AI will be the preferred tool to increase the accuracy in high-throughput crop phenotyping, genotyping, and envirotyping data; moreover, we explore the developing approaches and challenges for multiomics big computing data integration. Therefore, the integration of AI with “omics” tools can allow rapid gene identification and eventually accelerate crop-improvement programs.

Genetic Improvement in Sesame (Sesamum indicum L.): Progress and Outlook: A Review

Sesame production and productivity are severely constrained by a lack of high-yielding and locally adapted varieties, susceptibility to capsule shattering and low seed retention, biotic and abiotic stresses, and a lack of modern production and pre- and post-harvest technologies. Unimproved landraces are widely cultivated in sub-Saharan Africa, including Ethiopia. The landrace varieties are low yielders (<0.6 tons·ha−1), but they possess intrinsic seed oil quality characteristics, such as unique aroma and taste. Therefore, current and future sesame genetic improvement programs should integrate yield- and quality-promoting traits, local adaptation, amenability to machine harvesting, and other industrially essential food and feed attributes for multiple utilities. This can be achieved by integrating the conventional breeding methods, as well as genetic and genomic techniques such as mutation breeding and genomics-assisted breeding. Therefore, the objective of this review is to document the breeding progress, opportunities, and challenges of sesame with regard to genetic improvement, variety release, and deployment with enhanced seed yield and related agronomic traits, as well as oil content and fatty acid compositions. The review highlights sesame’s economic values, production status, major production constraints, conventional breeding methods, and genomics-assisted breeding, as well as their integration, for accelerated breeding and cultivar development with market-preferred traits.

Should I stay or should I go: factors influencing mate retention and divorce in a colonial seabird

Divorce among serially monogamous birds can lead to increased reproductive success if an individual obtains a higher-quality mate or nest site, or it can lead to lower reproductive success due to lack of pair experience or reduced breeding opportunities. Identifying the drivers and consequences of mate retention and divorce are necessary then to understand population dynamics, particularly as animals may alter behaviours in response to climate-induced environmental changes. We used a 33-year data set from a declining Magellanic penguin, Spheniscus magellanicus, colony to identify drivers of mate retention and divorce and test whether the nature of those drivers differed between first-year and long-term pairs. In a pair's first year, breeding outcome was the most important predictor of whether mates would reunite: failure rates were high and 71% of first-year pairs divorced on the whole, but only 47% of pairs that fledged a chick divorced. For long-term pairs, both breeding outcome and between-season changes to nest quality were the most important predictors of whether a pair stayed together: pairs that had a chick hatch or fledge divorced at lower rates than those that failed at the egg stage, and pairs whose nest quality declined were more likely to divorce. We also examined the fitness consequences of divorce by comparing the rates at which females and males obtained new mates and fledged chicks in the following year. Although females were more likely than males to secure a new mate, both sexes experienced similarly increased reproductive success with their new mates compared to their old mates, showing that divorce is adaptive.

Why do males stay in biparental burying beetles?

Abstract Biparental associations are rare in most taxa. A second parent should stay with its current brood only to enhance brood fitness or to increase its own future breeding opportunities. I compared the breeding performance of Nicrophorus defodiens pairs and single females while confronting a conspecific male intruder. Pairs fared better than single females in defending a brood, and age had a strong effect on contest outcomes even though defenders and intruders were of the same age. Pairs also produced larger broods than single females, but only on larger carcasses. The results and a review of prior studies suggest that the benefits for a male that stays with a partner during the post-hatch period, whether gains from offspring success or protecting mating opportunities, are observed primarily in the context of intruder pressure, and that paternal care such as regurgitations to young and nest maintenance would not have evolved in a rival-free world.

Optimized utilization of Salix—Perspectives for the genetic improvement toward sustainable biofuel value chains

AbstractBioenergy will be one of the most important renewable energy sources in the conversion from fossil fuels to bio‐based products. Short rotation coppice Salix could be a key player in this conversion since Salix has rapid growth, positive energy balance, easy to manage cultivation system with vegetative propagation of plant material and multiple harvests from the same plantation. The aim of the present paper is to provide an overview of the main challenges and key issues in willow genetic improvement toward sustainable biofuel value chains. Primarily based on results from the research project “Optimized Utilization of Salix” (OPTUS), the influence of Salix wood quality on the potential for biofuel use is discussed, followed by issues related to the conversion of Salix biomass into liquid and gaseous transportation fuels. Thereafter, the studies address genotypic influence on soil carbon sequestration in Salix plantations, as well as on soil carbon dynamics and climate change impacts. Finally, the opportunities for plant breeding are discussed using willow as a resource for sustainable biofuel production. Substantial phenotypic and genotypic variation was reported for different wood quality traits important in biological (i.e., enzymatic and anaerobic) and thermochemical conversion processes, which is a prerequisite for plant breeding. Furthermore, different Salix genotypes can affect soil carbon sequestration variably, and life cycle assessment illustrates that these differences can result in different climate mitigation potential depending on genotype. Thus, the potential of Salix plantations for sustainable biomass production and its conversion into biofuels is shown. Large genetic variation in various wood and biomass traits, important for different conversion processes and carbon sequestration, provides opportunities to enhance the sustainability of the production system via plant breeding. This includes new breeding targets in addition to traditional targets for high yield to improve biomass quality and carbon sequestration potential.