Breeding Stage Research Articles

Assessment of ecological plasticity and stability of promising potato hybrids of the Komi Republic (Russia)

In the Republic of Komi (Russia), one of the main agricultural vegetable crops cultivated by agro-enterprises, peasant farms and the population in the private sector is potatoes. The food security of Russia in the Arctic zone and obtaining competitive varieties for the regions of the Far North of our country is the main task solved by agricultural science in the field of breeding. New, promising varieties of potatoes must meet modern requirements for high yields obtained in various natural, soil and climatic conditions of their cultivation. In addition, varieties should have high stability in terms of commercial and economic characteristics and give an equivalent yield in constantly changing environmental conditions, both for the better (favorable) and for the worse (unfavorable). The use of modern methods of mathematical, statistical analysis, calculation of the assessment of environmental stability, plasticity, adaptability, as well as an objective and complete assessment of the potential of potato genomes, rigorous selection of promising lines and hybrids and screening for various negative traits, especially at the first stages of breeding, variety samples that do not correspond and do not satisfy these parameters, allow you to quickly obtain new varieties adapted to the Arctic zone of the Russian Federation. In order to strengthen breeding work aimed at breeding promising varieties of potatoes, in 2020-2022, a research program was carried out in breeding nurseries of the dynamic competitive first, second and third years of testing (hybrids of the sixth, seventh and eighth tuber generation) on the basis of the Institute of Agricultural Biotechnology of the Federal Research Center Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences (Russia, Syktyvkar). New promising potato hybrids (varieties) were selected as the object of study: 2341-265 (Amur x Gala), 2339-8 (Oksania x Gala), 2339-9 (Oksania x Gala), 1992-14 (Udacha x Elmundo), 2000-60 (Colette x FZ 1867); the standards were zoned and recommended for this region varieties of two groups of ripeness: Udacha - early, early ripening, Nevsky - medium early. As a result of research work in the course of a comprehensive assessment of ecological plasticity and stability, a promising potato hybrid 2000-60 was identified. This hybrid is characterized by stability to growing conditions,responsiveness to improved cultivation conditions, high average yield (33.7 t/ha).

Nutritivni sastav i bioaktivna svojstva integralnog brašna dobijenog od inbred linija kukuruza

The aim of this study was to assess the chemical composition and bioactive properties of the wholegrain flour obtained from eleven maize inbred lines to identify genotypes with increased potential for the development of hybrids with high nutritional and functional value, suitable for food production. The maize inbreds, including seven standard yellow, two QPM (quality protein maize) and two lines for red kernel hybrids, were grown in the experimental field of the Maize Research Institute at the location of Zemun Polje, Serbia. Wholegrain maize flour was got by grinding the maize grain in a laboratory mill. The assessment of the chemical composition and content of certain bioactive compounds, as well as the total antioxidant capacity, was conducted using standard laboratory procedures. The highest starch content (73.73%) was determined in line L8, while line L10 had the highest protein content (12.82%). Among soluble proteins, the a-zein fraction was dominant in most of the lines, ranging from 0.92% to 3.57%. The highest content of total fibres (NDF) was determined in red kernel line L9 (15.77%). Line L8 was the richest in total carotenoids (21.08 mg bCE/g d.m.), while line L7 had the highest total antioxidant capacity (34.30 mmol Trolox/kg d.m.), which can be explained by the presence of anthocyanins in the red grain. Line L1 had the highest content of total sugars (3.36%), and line L4 had the lowest (1.44%). Most of the samples of inbred lines investigated in this study showed good quality parameters regarding chemical composition and bioactive properties. The obtained results may provide some valuable guidelines needed in the following stages of maize breeding and open up various possibilities for the utilization of wholegrain maize flour in the food industry.

Heritability and amylose content in hybrid lines of late-generation rice with colored pericarp.

Improving grain quality in rice breeding is one of the main tasks. This concerns the creation of rice varieties with colored pericarp uncommon in the Republic of Kazakhstan, and the assessment of its quality is an important stage of breeding. Rice with colored pericarp is an important dietary crop, more useful for the human body than white rice. Regardless of the type of rice, the amount of amylose in rice grain is a crucial indicator that determines the quality of rice. The paper presents the results of electrophoretic separation of spare grain proteins of rice hybrids and dihaploids with colored pericarp and their parent forms obtained as a result of the hybridization of varieties with colored pericarp (Black Rice (China), Mavr (Russia), and Yir 5815 (Ukraine)) with white rice varieties zoned in Kazakhstan. The hybridization of the rice varieties with colored pericarp with white rice varieties was carried out to obtain rice varieties with colored pericarp oriented to the soil and climate of Kazakhstan. Analyzing the results of electrophoresis and the amount of amylose, it was found that hybrid lines differed in amylose content. One of the studied hybrids was high in amylose, four had a medium amylose content, ten had a low amylose content, three had a very low amylose content, and six were glutinous. According to the results of electrophoretic separation of spare rice grain proteins, the spectrum of the enzyme determining amylose was detected in five hybrids, which corresponds to the results of spectrophotometric determination of amylose: high amylose in one hybrid and medium amylose content in four. The results show that the hybrids obtained as a result of hybridization are true hybrids and as a result of long-term selection, the amylose content in the F7-F8 hybrids stabilized. The hybrids can be used in further breeding of rice with colored pericarp.

Adaptabilidade e estabilidade de linhagens de feijão-mungo na região médio-norte de Mato Grosso, Brasil

ABSTRACT Evaluation of genotype x environment interactions is essential in plant breeding aimed at adapting crops to new settings. Considering the need for research on the adaptation of mungbean to grain-production regions of Brazil, this study evaluated the agronomic performance, adaptability, and stability of mungbean production in the mid-north of Mato Grosso using different genotypes. Two experiments (with and without fertilizer application) were carried out in Sorriso and Sinop in 2019 and 2020, totaling eight environments. The treatments were 10 mungbean lines and the control cultivar BRSMG Camaleão. In general, significant differences among the treatments were observed in the yield, mass of 100 grains, and value for cultivation. The genotype x environment interactions were significant for yield. On average, the yield was in the range of 734-1305 kg ha-1, the mass of 100 grains was 4.63-6.56 g, and the value for cultivation was 2.08-3.56. Genotypes BRA-08654-1, BRA-000027, BRA-084654-2, and BG3 combined high average yield and mass of 100 grains. These genotypes also showed good adaptability for cultivation in the mid-north of Mato Grosso. The yellow seed-coated genotype BRA-084689 also showed good agronomic performance and adaptability. Genotypes BRA-08654-1, BRA-000027, BRA-084654-2, BRA-084689, and BG3 are promising for further experiments evaluating the value for cultivation and use, the final breeding stage consisting of tests at a national level.

Conceptual principles of food loss reduction and food waste

The article substantiates the conceptual principles of reducing food loss and food waste from the standpoint of ensuring food security and environmental sustainability. The approaches to the interpretation of the concepts of food loss and waste are summarized, the similarities and differences between them, as well as the reasons for their formation and the connection between them, are noted. The main causes of food losses and food waste, which are caused by human, technical-technological, natural-climatic, economic, market, etc., are considered. factors. It is argued that Ukraine's waging of war caused the deterioration of food security both at the local and national levels, and at the international level. The main factors that lead to the loss of agri-food in the supply chain during wartime and the decrease in its production volumes are systematized, which will negatively affect the provision of food security in the country and the formation of export potential at the level of previous years. The dynamics of losses in terms of individual types of products were analyzed and it was established that the highest losses are observed for potatoes - 18.1 %, vegetables and melons - 12.0 %, fruits and vegetables - 10.0 %, and for livestock products this indicator is not significant It was found that the greatest losses of crop products occur at the stage of growing and harvesting, the value of which varies from 3 to 12 %, as well as sales. In dairy and meat breeding, the greatest losses occur at the stage of livestock breeding, milking and primary processing of products, as well as due to the lack of a full production cycle. It is estimated that the amount of food waste in Ukraine in households is 76 kg per capita, which is almost equal to the indicators of most countries, but the values are higher in the catering sector - 28 kg and retail trade - 16 kg. It was concluded that there is a need to develop effective measures to reduce food waste and losses in order to increase the sustainability and competitiveness of agri-food supply chains. It is substantiated that the conceptual principles of the need to reduce food losses and food waste should be considered in the aspect of ensuring food security and minimizing the negative impact on the environment. Among the priority directions for solving the problem of food losses and waste, the following are highlighted: development of a comprehensive program for the preservation and restoration of agricultural production in the conditions of martial law; development and improvement of market infrastructure elements; technical and technological modernization of agricultural production, processing facilities; improvement of distribution infrastructure elements, especially transportation of live animals; creation of innovative warehouse facilities; formation of a rational consumption culture among the population; development of wholesale food markets, livestock markets, development of public-private partnerships in the implementation of projects to reduce food losses and food waste; development of effective levers of state regulation in the aspect of motivation of chain participants; development of a methodical approach to estimating the amount of food losses; formation of an information array of data, etc. Key words: food loss, food waste, supply chain, food security, environmental sustainability, martial law.

THE PRODUCTIVITY OF THE FIRST CALVING COWS OF DIFFERENT CONDITIONS GROWING AND HOUSING

Introduction. The purpose of the work was to study the influence of different conditions of rearing and housing of the first calving cows on their productivity, reproductive capacity and stayability during lactation at the current stage of breeding. Materials and methods of research. The work was carried out based on the data of four breeding plants for the breeding of Ukrainian black and white dairy cows. The data of 3.610 first calving cows that calved during the last six years were analyzed. Statistical processing of the obtained data was carried out by the method of two-factor variance analysis using computer programs. During the analysis, the data were divided by the age of first fertilization and the average daily gain before fertilization. Only animals with a duration of lactation of more than 200 days were selected to determine productivity indicators for lactation. The stayability was determined for the first 10 months of lactation. In determining the probability of abortion and stillbirth, calvings with stillborn calves and abortions after which lactation began are taken into account. Research results. It was established that the live weight of first calving cows, regardless of the housing, increased proportionally to the intensity of their growing. In stall housing, the live weight of first servis that were fertilized at different ages had no significant differences, while in free stall housing, the first calving cows that were inseminated before the age of 470 days had an advantage of 12–19 kg. In terms of milk yield for 305 days of lactation, the first calving cow that were kept tethered and were fertilized at an earlier age exceeded the animals of other groups by 29–148 kg of milk, and those kept without tethering by 564–989 kg. Intensively reared animals produced 244–539 kg of milk more when tethered, and when tethered, this difference was significantly greater and amounted to 530–1081 kg, compared to first calving cow with an increase of less than 800 g. A reading has been established for the trend of increasing the milk yields from the changes in the first fertilization. The intensity of the growth of the heifers before the flooding also has a positive impact on their day milk yield. The probability of unsuccessful calving does not depend on the age of the first insemination in stall housing, but in free housing, animals that were inseminated before 470 days of age had 36–46% more unfavorable results with calving than those that were inseminated in older age The probability of abortion and the birth of a dead calf during stall housing heifers with different intensities of growing before fertilization also had no significant differences, and during free housing heifers with an average daily gain of more than 800 g had 7–9 more cases of unsuccessful calving, calculated on 100 animal compared to heifers with a lower intensity of growing. Conclusions. Increasing the intensity of raising heifers and reducing the age of first insemination contribute to increasing their productivity. It is necessary to carry out constant monitoring of repair youngsters for fatness and to prevent obesity. It leads to a decrease in reproductive capacity, unfavorable calving and, as a result, an increase in the probability of culling in the first lactation, especially in in free housing.

Prevalence and Persistence of Ceftiofur-Resistant Escherichia coli in A Chicken Layer Breeding Program

We determined the longitudinal persistence of ceftiofur-resistant Escherichia coli from a chicken breeding farm in China. A total of 150 samples were collected from 5 breeding periods in a flock of layer hens, and the prevalence of ceftiofur-resistant E. coli fluctuated across the 5 chicken breeding stages: eggs, 3.33%; growing period, 100%; early laying period, 36.7%; peak laying period, 66.7% and late laying period, 80%. The most prevalent ceftiofur resistance genes were blaCTX-M-55, blaCMY and blaNDM, and ST101 was the most prevalent and persistent sequence type across the breeding periods. Our results indicated that this breeder flock was heavily contaminated by ST101 ceftiofur-resistant E. coli and that its presence should be intensively monitored on chicken farms.

Potential negative effects of the installation of video surveillance cameras in raptors’ nests

Video surveillance cameras installed on birds’ nests are a cost-effective tool to study many aspects of ecology and behaviour that would otherwise be practically impossible to obtain. However, although most studies report neutral effects of cameras on birds, very few studies analyse in detail the potential negative effects of their use, particularly on raptors. Here, using a long-term database of a population of Bonelli’s eagle (Aquila fasciata) collected from 2000 to 2022, I show how the inappropriate use of video surveillance cameras could result in negative effects on the reproduction of a threatened species through a before-and-after control-impact study design. Pairs under video surveillance showed lower productivity, lower breeding success and unusual delayed laying dates. The installation of cameras close to the laying date, coinciding with the mating phase of individuals, most of them subadult inexperienced birds; in combination to the reiteration of visits to the nests once the cameras were installed to check the system, particularly during the incubation period and early stages of breeding; and the installation of cameras in a particular area subject to constant human disturbance, might explain these results. Potential management actions to mitigate the effect of the installation of video cameras on birds’ behaviour should include the need to plan the intervention dates, testing the systems beforehand under controlled conditions and adequate post-installation monitoring to avoid unnecessary disturbance to animals. Finally, I urge the scientific community to report the potential negative effects observed in their studies, especially if the target species are threatened with extinction.

The Development of Forest Genetic Breeding and the Application of Genome Selection and CRISPR/Cas9 in Forest Breeding

With the birth of classical genetics, forest genetic breeding has laid a foundation in the formation of the basic theories of population genetics, quantitative genetics, cytogenetics, and molecular genetics. Driven by the rapid growth of social demand for wood and other forest products, modern genetics, biotechnology, biostatistics, crop and animal husbandry breeding theories, and technical achievements have been continuously introduced for innovation, thus forming a close combination of genetic basic research and breeding practice. Forest tree breeding research in the world has a history of more than 200 years. By the middle of the 20th century, the forest tree genetic breeding system was gradually formed. After entering the 21st century, the in-depth development stage of molecular design breeding was opened. With the continuous improvement of traditional genetic breeding methods, emerging modern bioengineering technology has also continuously promoted the development of forest genetic breeding. This study mainly summarizes the research history of forest tree genetics and breeding, as well as discusses the application of modern bioengineering technology represented by genome selection and gene editing in forest tree breeding, so as to provide better reference for forest tree breeding research.

Mitochondrial Features and Expressions of MFN2 and DRP1 during Spermiogenesis in Phascolosoma esculenta.

Mitochondria can fuse or divide, a phenomenon known as mitochondrial dynamics, and their distribution within a cell changes according to the physiological status of the cell. However, the functions of mitochondrial dynamics during spermatogenesis in animals other than mammals and fruit flies are poorly understood. In this study, we analyzed mitochondrial distribution and morphology during spermiogenesis in Sipuncula (Phascolosoma esculenta) and investigated the expression dynamics of mitochondrial fusion-related protein MFN2 and fission-related protein DRP1 during spermiogenesis. The mitochondria, which were elliptic with abundant lamellar cristae, were mainly localized near the nucleus and distributed unilaterally in cells during most stages of spermiogenesis. Their major axis length, average diameter, cross-sectional area, and volume are significantly changed during spermiogenesis. mfn2 and drp1 mRNA and proteins were most highly expressed in coelomic fluid, a spermatid development site for male P. esculenta, and highly expressed in the breeding stage compared to in the non-breeding stage. MFN2 and DRP1 expression levels were higher in components with many spermatids than in spermatid-free components. Immunofluorescence revealed that MFN2 and DRP1 were consistently expressed and that MFN2 co-localizes with mitochondria during spermiogenesis. The results provide evidence for an important role of mitochondrial dynamics during spermiogenesis from morphology and molecular biology in P. esculenta, broadening insights into the role of mitochondrial dynamics in animal spermiogenesis.

Partner intrinsic characteristics influence foraging trip duration, but not coordination of care in wandering albatrosses Diomedea exulans.

Long-lived monogamous species gain long-term fitness benefits by equalizing effort during biparental care. For example, many seabird species coordinate care by matching foraging trip durations within pairs. Age affects coordination in some seabird species; however, the impact of other intrinsic traits, including personality, on potential intraspecific variation in coordination strength is less well understood. The impacts of pair members' intrinsic traits on trip duration and coordination strength were investigated using data from saltwater immersion loggers deployed on 71 pairs of wandering albatrosses Diomedea exulans. These were modeled against pair members' age, boldness, and their partner's previous trip duration. At the population level, the birds exhibited some coordination of parental care that was of equal strength during incubation and chick-brooding. However, there was low variation in coordination between pairs and coordination strength was unaffected by the birds' boldness or age in either breeding stage. Surprisingly, during incubation, foraging trip duration was mainly driven by partner traits, as birds which were paired to older and bolder partners took shorter trips. During chick-brooding, shorter foraging trips were associated with greater boldness in focal birds and their partners, but age had no effect. These results suggest that an individual's assessment of their partner's capacity or willingness to provide care may be a major driver of trip duration, thereby highlighting the importance of accounting for pair behavior when studying parental care strategies.

Curves for Curlew: Identifying Curlew breeding status from GPS tracking data.

Identifying the breeding status of cryptic bird species has proved problematic without intense or inherently expensive monitoring. Most, if not all, intensive bird monitoring comes with disturbance risks and many projects now rely on tagging of individuals to provide remote information on movements. Given the importance of breeding status when targeting conservation interventions novel methods are needed. This study aimed to identify breeding status in Eurasian Curlew (Numenius arquata) from GPS tag movement patterns using the "recurse" package in R. This package identifies foci of activity (using K-means clustering) based on revisitations. Using a training data set from an individual of known breeding status, we visually assessed the frequency of revisits to particular locations to identify prebreeding, incubation, chick guarding, and post-breeding stages to an accuracy of a within at most half a day and thus breeding outcomes. Limited validation was provided by additional field observations. Based on our results, we estimate a low daily nest survival rate of 0.935 during incubation, that only a small proportion of individuals successfully raised young, and that there was a high proportion (26%) of non-breeders in the population. The Eurasian Curlew is a species of high conservation concern across Europe, and our results concur with recent studies highlighting that population declines are likely to be driven by low levels of productivity. The acquisition of improved knowledge on the behaviors of individuals at each stage of breeding enables more targeted conservation efforts and reduces the need for additional monitoring visits that may cause increased disturbance and risk of nest failure. We hope that the approach outlined may be developed to provide practitioners who have detailed knowledge of the behavior of their study species with a practical means of assessing the breeding status and outcomes of their study populations.

The effect of seabird presence and seasonality on ground-active spider communities across temperate islands.

Seabirds influence island ecosystems through nutrient additions and physical disturbance. These influences can have opposing effects on an island's invertebrate predator populations. Spiders (order: Araneae) are an important predator in many terrestrial island ecosystems, yet little is known about how seabird presence influences spider communities at the intraisland scale, or how they respond to seasonality in seabird colony attendance.We investigated the effects of seabird presence and seasonality on ground-active spider community structure (activity-density, family-level richness, age class, and sex structure) and composition at the family-level across five short-tailed shearwater breeding islands around south-eastern Tasmania, Australia. Using 75 pitfall traps (15 per island), spiders were collected inside, near, and outside seabird colonies on each island, at five different stages of the short-tailed shearwater breeding cycle over a year. Pitfall traps were deployed for a total of 2674 days, capturing 1592 spiders from 26 families with Linyphiidae and Lycosidae the most common. Spider activity-density was generally greater inside than outside seabird colonies, while family-level richness was generally higher outside seabird colonies. For these islands, seabird breeding stage did not affect activity-densities, but there were some seasonal changes in age class and sex structures with more adult males captured during winter. Our results provide some of the first insights into the spatial and temporal influences seabirds have on spider communities. We also provide some of the first records of spider family occurrences for south-eastern Tasmanian islands, which will provide an important baseline for assessing future change.

Quality attributes of garden strawberry fruits and breeding for their improvement

Based on the analysis of domestic and foreign literary sources the information about the main quality attributes of garden strawberry fruits (large fruit size, hardness or firmness of fruits, biochemical composition) and breeding possibilities of their improvement at the present stage of breeding is summarized. Quality characteristics of garden strawberries are differentiated by groups: commercial, consumer, biochemical, physical and mechanical, technological. When growing garden strawberries for fresh consumption, the following large-fruited varieties were identified: Clery (Italy), Florence (UK), Alba (Italy), Roxana (Italy), Vima Xima (Netherlands), Vima Tarda (Netherlands), Vima Kimberly (Netherlands), Maya (Italy), San Andreas (USA), Taira, Nelly, Kemiya, Elegy, Alpha, Bereginya, Tsaritsa, Krymchanka 87, Arossa, Zarya, Krymskaya rannaya, Uniol, Jantarnaja. The trait of fruit hardness refers to the technological characteristics, but it also depends on the appearance of fruits during harvesting and transportation, which determines the commercial appearance. The following varieties have a high degree of fruit hardness: Tsaritsa, Surprise olympics, Rubinovy kulon, Feyerverk, Aquarelle, Alina, Nelli, Induka (Netherlands), Clery, Darselect (France), Tenira (Netherlands), Selekta (Canada), Polka (Netherlands), Irma (Italy), Alba, Asia (Italy), Syria (Italy), Onda (Italy), Vivaldi (Netherlands). Strawberry fruits are characterized by a unique composition of biologically active compounds that determine the nutritional value of the crop as a source of dietary and therapeutic and preventive nutrition. Studies indicate a predominant role of genotype in the accumulation of antioxidants in garden strawberry fruits, as well as the influence of growing conditions on the realization of the genetic potential of the varieties. Due to the development of cultivation technologies and the expansion of knowledge about the nutraceutical value of garden strawberries, improving the quality of fruits has become one of the priority objectives of breeding programs around the world. To increase the level of fruit quality traits in garden strawberry, the greatest effect can be achieved by using the original forms with proven donor properties on these traits in breeding.

Assessment of Garlic Production Constraints and Trait Preferences in Garlic Cultivar Development in Two Woredas, Sidama Region, Ethiopia

Garlic (Allium sativium L.) is the major food and cash crop in the highland regions of Ethiopia. However, farmers are not integrated into the garlic breeding process. The objectives of this assessment were to identify farmers’ key garlic production constraints and establish preferred traits in garlic cultivar development in the two woredas of Sidama Region (Ethiopia). A participatory rural appraisal (PRA) study was conducted through a structured survey involving 36 households in Malga and Gorche woredas. A structured survey used a questionnaire which was administered to farmers to collect information on key production constraints, varieties of garlic seed used for production, seed source etc., according to the assessment result of this study, the cultivar used for garlic production is the local variety in the two woredas. Hence, the most important garlic production constraints are lack of high yielding cultivars, garlic disease and insects. To conclude active farmer participation in early breeding stages is critical for a successful garlic breeding program. Based on the assessment it is possible to recommend that high yielder garlic variety, disease tolerance, insect resistant and cultivars having high dry matter content are the most important parameters preferred by farmers, which helps them to produce maximum products and serve as a source of income to many rural farmers.

Results of the first year of sturgeon hybrid breeding in an industrial fishery

The paper presents the results of rearing hybrid breeding (Siberian sturgeon × beluga sturgeon (SS×BS), Russian sturgeon × beluga sturgeon (RS×BS), and Russian sturgeon × kaluga sturgeon (RS×KS)) in a recirculating aquaculture system (RAS) and flow-through tanks at the Konakovo Division of the Branch for Freshwater Fisheries of the Federal State Budget Scientific Institution “Russian Federal Research Institute of Fisheries and Oceanography” (VNIIPRKH). The productive and biological characteristics of the arental sturgeon species used to obtain hybrids are discussed. The Siberian sturgeon × beluga sturgeon hybrids produced the most viable. The first stage of breeding in a RAS revealed that juvenile RS×BS and SS×KS hybrids had the best weight gain coefficient, with an average water temperature in rearing tanks of 16.9 °С. During the second stage of rearing in flow-through tanks, hydrological and hydrochemical conditions were generally similar for all intergeneric hybrids. This allowed us to compare the productive and biological characteristics. During the rearing period of 206 days in flow-through tanks, at an average water temperature of 19.5 °С and thermal constant of 3,519.2 degree days, SS×BS hybrid had the best weight gain coefficient and, consequently, the best average body weight (329 g). However, its survival rate was the lowest (48.8%). RS×BS hybrid showed intermediate results for the average body weight (249 g) and survival (72.3%). RS×KS hybrid showed the lowest growth and average body weight (190 g), but the highest survival rate (81.0%). It was discovered that the temperature conditions in flow-through tanks are quite favorable for sturgeon breeding during the summer. Thus, seeding for sturgeon hybrids can be carried out not only in a RAS, but also in flow-through tanks.

New techniques for breeding maize (Zea mays) varieties with fall armyworm resistance and market‐preferred traits for sub‐Saharan Africa

AbstractDeploying maize varieties with fall armyworm (Spodoptera frugiperda [J.E. Smith]; FAW) resistance, desirable product profiles (PPs) and climate resilience is fundamental for food and economic security in sub‐Saharan Africa (SSA). This study reviewed and identified challenges and opportunities for effective and accelerated breeding of demand‐led maize hybrids with FAW resistance and adaptation to the diverse agro‐ecologies of SSA. Lessons were drawn on improving breeding efficiency through adequate genetic variation delivered via prebreeding programmes, speed breeding and a reduced breeding stage plan. Appropriate PPs aligned with demand‐led breeding approaches were highlighted as foundations for variety design and commercialization. Challenges to accelerated FAW resistance breeding in maize included inadequate funds and modern tools; poor adaptation of some exotic donor parental lines; lack of information on FAW resistance among local varieties; lack of integration of molecular markers associated with FAW resistance and agronomic traits into selection plans; and limited infrastructure for FAW rearing and germplasm screening. Integration of modern breeding tools and scientific innovations were recommended for accelerated development and release of FAW resistant and market‐preferred maize varieties.

Lipid accumulation and oxidative stress in the crop tissues of male and female pigeons during incubation and chick-rearing periods

The current study aimed to evaluate the changes in lipid accumulation and oxidative status in pigeon crops during different breeding stages. Forty-two pairs of adult pigeons were randomly assigned to 7 groups. Lipid droplet accumulation in pigeon crops was visualized by using oil red O staining from d 17 of incubation (I17) to d 7 of chick rearing (R7). Transmission electron microscopy analysis showed swollen mitochondria with disintegration of cristae and typical characteristics of endoplasmic reticulum stress in crop tissues at R1 compared with those at I4. During the peak of pigeon milk formation, the concentrations of reactive oxygen species, and oxidative damage markers (advanced oxidation protein products, 8-hydroxy-2 deoxyguanosine, and malondialdehyde) and the enzyme activities of total superoxide dismutase and glutathione peroxidase were all elevated significantly (P < 0.05). The protein concentration of B-cell lymphoma-2 associated X in crop tissues was significantly higher at R1, while the level of B-cell lymphoma-2 protein in males was the highest at I4 (P < 0.05). The ratio of B-cell lymphoma-2 associated X protein (Bax)/B-cell lymphoma-2 (Bcl-2) in both male and female crops peaked at R1 (P < 0.05). Gene expression of the key enzymes involved in mitochondrial and peroxisomal fatty acid β-oxidation was investigated in crops. In males, the gene expression of carnitine palmitoyltransferase 1a peaked at R15, and that of carnitine palmitoyltransferase 2 increased significantly from R1 to R15 (P < 0.05). The mRNA abundance of long chain 3-hydroxyacyl-CoA dehydrogenase increased to the maximum value at R1 and I17 in males and females, respectively. From I17 to R7, the mRNA levels of acyl-CoA oxidase 1 and acyl-CoA oxidase 2 were decreased in pigeon crops (P < 0.05). Conclusively, lipid droplet accumulation was found in male and female pigeon crops from the end of incubation to the early stage of chick rearing. Although antioxidant defence and mitochondrial fatty acid β-oxidation were both mobilized, oxidative stress in crop tissues still occurred during the peak of milk formation.

Breeding stage and tissue isotopic consistency suggests colony-level flexibility in niche breadth of an Arctic marine bird.

Organisms must overcome environmental limitations to optimize their investment in life history stages to maximize fitness. Human-induced climate change is generating increasingly variable environmental conditions, impacting the demography of prey items and, therefore, the ability of consumers to successfully access resources to fuel reproduction. While climate change effects are especially pronounced in the Arctic, it is unknown whether organisms can adjust foraging decisions to match such changes. We used a 9-year blood plasma δ13C and δ15N data set from over 700 pre-breeding Arctic common eiders (Somateria mollissima) to assess breeding-stage and inter-annual variation in isotopic niche, and whether inferred trophic flexibility was related to colony-level breeding parameters and environmental variation. Eider blood isotope values varied both across years and breeding stages, and combined with only weak relationships between isotopic metrics and environmental conditions suggests that pre-breeding eiders can make flexible foraging decisions to overcome constraints imposed by local abiotic conditions. From an investment perspective, an inshore, smaller isotopic niche predicted a greater probability to invest in reproduction, but was not related to laying phenology. Proximately, our results provide evidence that eiders breeding in the Arctic can alter their diet at the onset of reproductive investment to overcome increases in the energetic demand of egg production. Ultimately, Arctic pre-breeding common eiders may have the stage- and year-related foraging flexibility to respond to abiotic variation to reproduce successfully.

Multi‐omics provides new insights into the domestication and improvement of dark jute ( Corchorus olitorius )

Jute (Corchorus sp.) is the most important bast fiber crop worldwide; however, the mechanisms underlying domestication and improvement remain largely unknown. We performed multi-omics analysis by integrating de novo sequencing, resequencing, and transcriptomic and epigenetic sequencing to clarify the domestication and improvement of dark jute Corchorus olitorius. We demonstrated that dark jute underwent early domestication and a relatively moderate genetic bottleneck during improvement breeding. A genome-wide association study of 11 important agronomic traits identified abundant candidate loci. We characterized the selective sweeps in the two breeding stages of jute, prominently, soil salinity differences played an important role in environmental adaptation during domestication, and the strongly selected genes for improvement had an increased frequency of favorable haplotypes. Furthermore, we speculated that an encoding auxin/indole-3-acetic acid protein COS07g_00652 could enhance the flexibility and strength of the stem to improve fiber yield. Our study not only provides valuable genetic resources for future fiber breeding in jute, but also is of great significance for reviewing the genetic basis of early crop breeding.