Hybrid Genotypes Research Articles

Prevalence and abundance of Anisakis larvae in ready-to-eat mackerel products in Japan

The risk of contracting anisakiasis from consuming ready-to-eat (RTE) mackerel products in Japan was investigated by examining the prevalence and abundance of Anisakis simplex and its sibling species in these products. From 2019 to 2021, a total of 448 RTE mackerel products were purchased in Japan. Anisakis larvae were isolated from 244 of the 448 samples (54 %), and live larvae were isolated from 161 of the 448 samples (36 %). In total, 3170 Anisakis larvae, which included 919 live larvae, were isolated. The isolated Anisakis larvae consisted of 3118 A. simplex (s. s.), 27 A. pegreffii, and 25 hybrid genotype (A. simplex [s. s.] × A. pegreffii) larvae. No A. berlandi larvae were isolated. The prevalence of larvae in samples of mackerel caught in the Southern Japan region and Sea of Japan was much lower than that in mackerel caught in other areas. Both the prevalence of Anisakis larvae in all samples and their abundance in larvae-positive samples exhibited specific seasonal variations, being high in spring.

Breeding sugar-fodder beet hybrids for biofuel production

Topicality. The development of biofuel engineering in Ukraine demands to cultivate the agrofuel crops as renewable energy sources. The sugar-fodder hybrids created using high-value sterile forms of sugar beet and fertile forms of fodder beet may hold promise for biofuel feedstock production. Purpose. Develop experimental sugar-fodder beet hybrids with high energy yield, suitable for alternative biofuels production, and select the best ones. Materials and Methods. 6 pollen-sterile breeding lines of sugar beet and 23 selection numbers of fertile fodder beet were used to create the sugar-fodder hybrids. The breeding process comprised the following steps: selection of initial parental lines, evaluation them by combining ability, and, based on the best, formation of the hybrids. Method of multi-tester top crossing was applied and field trials of the experimental hybrids held. Results. The parent components varied significantly in energy yield, which ranged within 53.5–61.5 GJ/ha (for the MS-samples) and from 80.0 to 87.8 GJ/ha for the top 4 pollinators. On completion of the tester crosses, the following have been selected: MS-samples of the sugar beet lines MS Iv. 24869 and MS Iv. 2484 with proven significant effects of general combining ability at 6.7 GJ/ha and 4.0 GJ/ha; and pollinators of the fodder beet varieties Halytskyi and Lvivskyi zhovtyi – at 8.0 GJ/ha and 6.5 GJ/ha, respectively. In the genotypic structure of variability of the “energy output” trait, the total share of the influence of valuable additive gene complexes of parental samples (51 %) was almost equivalent to the share of non-additive interaction of components (49 %). Conclusions. By the method of combinative selection, three new genotypes of sugar-fodder hybrids have been developed, with energy output rate higher than 120 GJ/ha, suitable for the biofuel production from renewable sources. These are the genotypes MS Iv. 24869/k 41/42; MS Iv. 24869/k 13/14; and MS Iv. 24869/s. Lvivskyi zhovtyi, with indicators exceeding the standard by 14.3 %, 15.4 % and 8.5 %, respectively. Keywords: bioenergy, pollen-sterile forms, pollinators, sugar-fodder hybrids, combining ability, energy yield

Nutritive Profile, Digestibility, and Carbohydrate Fractionation of Three Sugarcane Genotypes Treated with Calcium Oxide

The objective of this study was to evaluate the use of calcium oxide (CaO) on the nutritive profile, digestibility, and carbohydrate fractionation of three sugarcane (Saccharum officinarum hybrids) genotypes: IAC-862480, SP-791011, and CTC-3. Four CaO levels (0, 1.5, 3.0, and 4.5% on a fresh matter basis) were used in a 3 × 4 factorial scheme, whose factors were the three sugarcane genotypes and the four levels of calcium oxide. The chemical composition, carbohydrate fractionation, total digestible nutrients, and in vitro dry matter digestibility (IVDMD) were evaluated. The chemical composition of the treated sugarcane was affected by the genotype and the use of CaO. The CTC-3 genotype showed lower values of crude protein (CP), ether extract (EE), neutral detergent fiber (NDFap), acid detergent fiber (ADF), and phosphorus (p < 0.01) contents when compared to the IAC-862480 genotype. A decreasing linear effect (p < 0.01) of CP, EE, ADF, lignin, cellulose, non-fibrous carbohydrates, and total digestible nutrients was observed with increasing levels of CaO. A quadratic effect was observed for the contents of DM, organic matter, NDFap, and hemicellulose when the sugarcane was treated with CaO (p < 0.05). The treatment of sugarcane with CaO resulted in the reduction (p < 0.05) in the indigestible fraction of sugarcane. The IAC-862480 and SP-791011 genotypes showed a better nutritional profile compared to the CTC-3 genotype. On the other hand, CaO treatment improved IVDMD and decreased the non-digestible fraction of sugarcane.

Anisakis infection in anchovies (Engraulis encrasicolus) from Iberian waters, southwestern Europe: Post-mortem larval migration

The Anisakis larvae presence in fish for human consumption is a health risk that needs to be monitored. The anchovy is a fish that is highly appreciated by consumers and that can harbour Anisakis. It is thus necessary to periodically evaluate the presence of anisakid larvae in them. So, anchovies from Iberian Peninsula coasts were analysed. Fish examination for macroscopic nematodes showed L3s of both Anisakis type I and Hysterothylacium aduncum. The Anisakis prevalence varies with the catching area and the fish size. The muscle prevalence was 7.45% (mean intensity 1.75; range 1-5). Molecular analysis showed 110 A. simplex s.s. (17 in muscle), 22 A. pegreffii (3) and 7 hybrid genotype individuals (1). Considering that most of the Iberian Peninsula coasts are a sympatry area between these two Anisakis species, it has been observed that A. simplex s.s./A. pegreffii ratio increases from south to north in a clockwise direction. Also, 19 larvae were detected on the fish surface from the Bay of Biscay, indicating the ability of these larvae to migrate after the fish death. The A. simplex s.s./A. pegreffii larvae proportion found on the anchovy surface is similar to the found in viscera and lower than in muscle, suggesting that most of the larvae migrating to the surface must have come from the visceral package. This confirms the importance of removing fish viscera immediately after capture, for those fish species where this is possible. As both species cause anisakiasis/anisakidosis, these data show a real risk to human health, especially in dishes highly prized in Mediterranean countries prepared with raw or semi-raw anchovies.

Transcriptional responses to 2,4-D herbicide treatment of a Eurasian (Myriophyllum spicatum) and a hybrid (M. spicatum × M. sibiricum) genotype of watermilfoil that differ in their sensitivity to 2,4-D

Aquatic plant managers frequently treat Eurasian watermilfoil (Myriophyllum spicatum L.; EWM) and hybrid watermilfoil (Myriophyllum spicatum L. × Myriophyllum sibiricum Komarov) with 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide. However, watermilfoil genotypes can differ in their response to 2,4-D. In this study, we compared facultative and constitutive gene expression differences for two watermilfoil genotypes (one Eurasian and one hybrid) that differ in their sensitivity to 2,4-D. To do this, we compared between control and 0.5 mg L−1 2,4-D treated plants at four time points after treatment. We also assembled the first de novo watermilfoil transcriptome. We found that while qualitatively similar, the facultative transcriptional response of the EWM genotype to 2,4-D treatment was much stronger than the hybrid genotype, indicated by a greater number and log-fold-change of differentially expressed genes at all time points after treatment. Further, we found that the EWM and hybrid genotype differed in their 9-cis-epoxycarotenoid dioxygenase (NCED) and abscisic acid (ABA) gene response, and that there was a greater amount of photosynthesis gene downregulation (both in number and log-fold-change) in the EWM than the hybrid genotype. At the constitutive level, overall, the hybrid expressed genes at a higher level than the EWM genotype, but not the genes of the 2,4-D response pathway. These differences in gene expression match with the degree of phenotypic difference in growth observed between these genotypes when exposed to 2,4-D. The hybrid genotype used here mitigates the effects of 2,4-D treatment better than the EWM genotype at both the molecular and phenotypic level. More study is needed to understand the mechanism(s) of mitigation and whether this is a cause of hybridity, or the specific genotypic backgrounds used here.

Assessment of maturity stage and stability of new Indonesian melon cultivar ‘Melona’ based on ISSR markers and morphological characteristics

Abstract. Yusuf AF, Alfiyani A, Salsabila TAS, Kusnanda PS, Hidayati IN, Daryono BS. 2023. Assessment of maturity stage and stability of new Indonesian melon cultivar ‘Melona’ based on ISSR markers and morphological characteristics. Biodiversitas 24: 308-316. Market preferences for horticultural products determine the product’s selling value and absorption. One market criterion often used for the quality of horticultural products is color and maturity level. Color differences can provide a representation of the metabolites contained in a product. This study provides a standard for assessing melons' maturity level, which will be helpful as a benchmark for Indonesian consumer acceptance. In addition, this study also provides information on the stability of the character of the new cultivar 'Melona' from several generations of crosses to obtain superior cultivars. Assessment of maturity level based on color development in 'Melona' is divided into five stages. In the first and second stage, fruit was dominated by green color with Increasing fruit volume. The color change begins in the third stage. in the third stage and the following phases, there is an increase in the accumulation of beta-carotene and characterized by the dominance of orange instead of green. Maximum ripe of ‘Melona’ is characterized by strong yellow lobes, creamy-white interlobes, and orange flesh color. A molecular analysis employing four ISSR primers (UBC-807, UBC-808, UBC-811, and UBC-824) resulted in high uniformity and low genetic variation in the hybrid and parent lines genotype. Analysis resulted a total of 42 DNA fragments with only one polymorphic DNA fragment. The polymorphic DNA fragment was 2,300 bp in size and was found in the female accession 'Melona' and the hybrid 'Melona' based on the UBC-808 primer. The numerical phenetic relationship between male, female and hybrid accession melon cultivars is very close (above 97.6%) and indicated that the melona cultivars were stable.

Development of energy plants from hybrids between Miscanthus sacchariflorus and M. lutarioriparius grown on reclaimed mine land in the Loess Plateau of China.

Miscanthus, a promising bioenergy plant, has a high biomass yield with high cellulose content suitable for biofuel production. However, harsh climatic and poor soil conditions, such as barren lands or abandoned mines, pose a challenge to the survival and yield of Miscanthus feedstock on the marginal land. The selection from the interspecific hybrids of Miscanthus might combine high survival rates and high yield, which benefits energy crop development in multi-stressful environments. A total of 113 F1 hybrids between Miscanthus sacchariflorus and M. lutarioriparius together with the parents were planted and evaluated for multiple morphological and physiological traits on the mine land of the Loess Plateau of China. The majority of hybrids had higher establishment rates than M. sacchariflorus while M. lutarioriparius failed to survive for the first winter. Nearly all hybrid genotypes outperformed M. lutarioriparius for yield-related traits including plant height, tiller number, tiller diameter, and leaf area. The average biomass of the hybrids was 20 times higher than that of surviving parent, M. sacchariflorus. Furthermore, the photosynthetic rates and water use efficiency of the hybrids were both significantly higher than those of the parents, which might be partly responsible for their higher yield. A total of 29 hybrids with outstanding traits related to yield and stress tolerance were identified as candidates. The study investigated for the first time the hybrids between local individuals of M. sacchariflorus and high-biomass M. lutarioriparius, suggesting that this could be an effective approach for high-yield energy crop development on vast of marginal lands.

The effect of grafting on pollen fertility and seed production of diploid interspecific hybrid and tetraploid eggplant genotypes

Solanum melongena is susceptible to diverse diseases and parasites, in particular the wilts (bacterial, Fusarium and Verticillium), nematodes, and some insects. Solanum torvum is robust to Verticillium and some bacterial wilts and root-knot nematode. It was reported that interspecific hybrid plants originated out of the hybridization of these species were sterile. In our previous studies that have been carried out to overcome this interspecific hybridization barrier, only from Faselis F1 that was used as the female parent, many interspecific hybrid seeds were obtained and 9.07% of the seeds grew into plants in vitro. The percentage of pollen viability and germination of tetraploid interspecific hybrid (amphidiploid) genotypes that have been produced by in vitro colchicine treatment, were 6.8 and 3.4 fold of its source diploid genotype, respectively. However, the increment was not high enough to overcome the interspecific hybridization barrier between S. torvum and S. melongena. In this study, the changes in pollen fertility of diploid interspecific hybrids and tetraploid plants, which have grafted on Pala or Faselis F1 , were investigated. Pollen viability and germination percentage in diploid genotypes were not affected by grafting, although they increased significantly (51.54% and 119.73%, respectively) in tetraploid genotypes by grafting. It was determined that the fertile diploid rootstock used for the tetraploid genotypes that produced by chromosome doubling from cultured eggplants could increase the number of seeds per fruit. It was concluded that some fertile diploid varieties can be used as rootstocks in order to increase pollen viability, germination rate and seed yield of tetraploid genotypes with low pollen yield obtained from cultivated eggplant by chromosome doubling.

Breeding of sugar beet hybrids suitable for the production of biofuel

The development of bioenergy in Ukraine requires the cultivation of energy crops as renewable sources of energy. Sugar beet hybrids created using valuable sterile and fertile forms can have a breeding perspective as a raw material for the production of biofuel. Therefore, the goal is to create experimental hybrids of sugar beets with high energy output, suitable for obtaining alternative types of biofuel, and to select the best of them. When creating sugar beet hybrids, 6 pollensterile and fertile samples of different ecological and genetic origins were used. The stages of the breeding process were the breeding of the original parental components, their evaluation by combining ability, and the formation of sugar beet hybrids based on the best of them. The method of multi-tester top-crosses and field tests of experimental sugar beet hybrids were applied. It was found that the parental components of sugar beet significantly differed among themselves in terms of bioethanol yield, the indicators of which ranged from 2.06 to 2.43 t/ha (TCS lines) and 2.23 to 2.73 t/ha (pollinators). The highest energy yield in topcross hybrids of sugar beets was noted in combinations created with the participation of polliniferous samples Iv.24869 (61.5 GJ/ha) and Iv.24845 (58.4 GJ/ha). Their effects of ZKZ were reliably positive and amounted to 6.7 and 4.0 GJ/ha, respectively. Numbers 1233-Jan.3 (2x) and 1183 02024 (2x) were recognized as the best pollinators of sugar beets. In the genotypic structure of variability of the "sugar yield" trait, the total share of the influence of valuable additive gene complexes of sugar beet parental forms (51 %) was almost equal to the share of non-additive interaction of components (49 %). By the method of combinatorial breeding, two new hybrid genotypes of sugar beets, suitable for the production of biofuel from renewable sources, were created, in which the energy yield exceeded the group standard by 10.6 and 12.6 %. Key words: bioenergy, sterile forms, pollinators, sugar beet hybrids, combining ability, energy output.

THE STUDY REGARDING THE AMPELOGRAPHIC CHARACTERIZATION OF SOME HYBRID ELITES AT I.N.C.D.B.H. ŞTEFĂNEŞTI

This paper aims to highlight the morphological descriptors analyzed of hybrid genotypes obtained by intraspecific hybridization of Victoria x Black Pearl, Muscat de Pölöskei x Victoria, Coarnă neagră x Victoria și Victoria x Victoria. The determination of the presented descriptors was done according to the O.I.V. (Office International of Vine and Wine) regulations and consisted in the preparation of ampelographic sheets of the hybrid elite for table grapes, recently obtained at the National Research and Development Institute for Biotechnologies in Horticulture Stefanesti Arges. The ampelographic cards constitute an important database for the identification of varieties and at the same time create the premises for a better management of the viticultural genetic heritage, in accordance with the regulations of international organisms/bodies.

Effect of the prolactin gene polymorphism on quantity and quality of milk in Iraqi goats

Domestic goats in Iraq are one of the oldest domesticated animals in Mesopotamia. Their adaptation characterizes them to harsh environmental conditions such as heat in the summer and cold in the winter. Still, they suffer from neglect and the lack of genetic research that would improve the production of this animal, which is considered a multi-production (milk production, meat production, hair production). And because the prolactin gene is crucial, the current study focused on how the prolactin gene (PRL) affects milk yield and its composition. We obtained three genotypes of the prolactin gene exon 5: AA, AB, and BB. The hybrid genotype AB had the highest daily milk yield in domestic goats, although the recessive type BB had a more significant fat percentage. The genetic approach is advised if breeding aims to enhance milk output daily. So select hybrid genotype AB to exon 5 for the (PRL) gene. . Keywords: Domestic Iraqi goats; prolactin gene; milk production

Evaluation of Hot Pepper Genotypes (Capsicum annum) in Western Terai of Nepal

A set of experiment was conducted to find the best hot pepper genotypes for the Western Terai of Nepal in the October, 2017 and April, 2018 at Agricultural Research Directorate, Lumbini Province, Khajura. The experiments were conducted in Randomized completely block design with four replications. The treatments consisted of hybrid genotypes SV1947HA, SV4884HA, SV2319HA, SV1551HA; two hybrids check cultivars NS 1701 and NCH-1120 and Pusa Jwala which is check open pollinated cultivar of hot pepper. In normal (October) season planting, the highest fresh yield (15.17 t/ha) was obtained from NS 1701 and similar yield was obtained from the genotype SV1947HA (13.86 t/ha) while in the off season (April) planting, the highest fresh yield (7.97 t/ha) was obtained from NCH-1120 and same level of yield with genotypes SV1551HA (6.83 t/ha). Highly significant differences among cultivars were observed in yield and yield attributing characters. Hot pepper yield were observed lower in the April planting due to the crop failure by disease in the heavy rainfall period. The genotypes with better fruit set and yield in respective growing season were needed to be further tested in order to ensure their performance.

Concurrent time course of xylem hydraulic dysfunction and non-structural carbohydrates under contrasting water deficits and nitrogen supplies in poplar

We compared the temporal dynamics of growth, leaf gas exchange, xylem hydraulic dysfunction and non-structural carbohydrates (NSC) of two poplar hybrid genotypes subjected to a differential nitrogen (N) supply under contrasting water deficits. Moderate water deficit generated intermediate embolism rates (45–70%) but had marginal effects on NSC. Severe water deficit generated progressive hydraulic failure and NSC reduction, leading to tree death within 90 days. At death, NSC in perennial tissues were not entirely depleted because of remaining soluble sugars. Higher N availability primarily affected growth and NSC dynamics (mainly starch), not embolism dynamics. The faster growing genotype benefiting most from N addition ceased growth and photosynthesis almost simultaneously, with no effect of N addition on process cessation, leading to progressive starch depletion during severe drought. In contrast, the slower growing genotype ceased growth before photosynthesis, leading to a transient increase in starch concentration during early drought stages, but this tended to be suppressed by higher N availability. Altogether, our findings indicate that carbon starvation alone is unlikely in hydraulically vulnerable species such as poplar even under prolonged moderate water deficit, but starch relative depletion covaries in time with progressive hydraulic failure under lethal water deficit. Nutritional status has the potential to shape drought responses, primarily through adjustments in carbon source-sink relations rather than in intrinsic xylem hydraulics, in a genotype-dependent manner. Exploring how hydraulic and carbon safety margins can be coordinated within species would be valuable in understanding how variation in drought response strategies can be exploited in breeding/selection.

Meiosis and male fertility in F1 interspecific hybrids (Passiflora vitifolia vs. Passiflora hatschbachii)

Interspecific hybrids can be studied using methodologies in which the male gamete with high reproduction potential, viability, and fertility is prioritized. Passiflora species, with lush, showy, and exotic colors, have great potential for the ornamental plant market. In addition, artificial Passiflora hybrids were developed without many difficulties because of weak reproductive barriers. Thus, meiotic and post-meiotic behaviors were analyzed with 2% acetic carmine staining. Confirmation of interspecific hybridization was performed using SSR markers and GISH technique was used to detect genomic differentiation. The pollen viability of the parental and hybrids genotypes was tested using Alexander`s solution, fluorescein diacetate and in vitro germination tests were performed using culture medium. The meiotic behavior was regular and displayed haploid number n = 9 with nine bivalent (II) chromosomal, and pairing in 90% of the cells in diakinesis. There was a significant difference (p < 0.05) in terminal and interstitial chiasma frequencies. Meiotic irregularities observed were as follows: early and/or delayed chromosomes, disorientation of spindle fibers, transverse spindles, tripolar spindles, and asynchrony; and consequently irregular post-meiotic products were observed: monads, dyads, triads, and polyads. GISH was used in the interspecific hybrids and pairing between homeologous chromosomes, and bivalent and tetravalent formation were observed. From this study, we could conclude that hybrid genotypes are fertile and pollen grains are viable and can be used in breeding programs.

Selection of High Yield and Stable Maize Hybrids in Mega-Environments of Java Island, Indonesia

Determination of grain yields of stable and high-yielding maize hybrids in a wide environment requires high accuracy. Many stability measurement methods have been used in multi-environment experiments. However, the relationships among the different methods are still difficult to understand. The objectives of this study were to 1. Identify the effect of growing season and location (Environments = E), hybrids (Genotypes = G), and their interactions (GEIs) on grain yields; 2. Select high-yielding and stable maize hybrids in a wide range of environments; 3. Determine the relationship between each stability estimation; and 4. Determine the mega-environment of maize hybrid and identify the best locations for testing. Field experiments were conducted at ten locations in Java Island, Indonesia, for two growing seasons using a randomized completed block design with three replications. The experimental results showed that the main effects of the growing season, location, hybrid, and GEIs, significantly affected maize hybrid yields. Stability estimations of TOP, S(3), S(6), NP(2), NP(3), KR, NP(4), CVi, and bi, belong to the concept of dynamic stability that can be used to select maize hybrids in favorable environments, while other estimations were classified as in the static stability. Three maize hybrids were successfully selected, with high and stable yields based on numerical and visual stability estimations, namely SC2, SC7, and SC9. The three hybrids can be used as candidates for sustainable maize development programs. The dry season, the rainy season, and the combination of two growing seasons produced three mega-environments. GJRS and KARS were the most discriminative environments. Both environments can be used as favorable environments for selecting the ideal maize hybrid.

Substantial genetic mixing among sexual and androgenetic lineages within the clam genus Corbicula

“Occasional” sexuality occurs when a species combines clonal reproduction and genetic mixing. This strategy is predicted to combine the advantages of both asexuality and sexuality, but its actual consequences on the genetic diversity and species longevity are poorly understood. Androgenesis, a reproductive mode in which the offspring inherits its entire nuclear genome from the father, is often reported as a strictly clonal reproductive mode. Androgenesis is the predominant reproductive mode within the hermaphroditic, invasive lineages of the mollusk genus Corbicula. Their ability to reproduce clonally through androgenesis has been determinant in their invasive success, having colonized during the 20th century American and European freshwater systems, where they became notorious invaders with a widespread, global distribution. However, in androgenetic Corbicula clams, occasional genetic mixing between distinct lineages has also been observed when the sperm of one lineage fertilizes the oocyte of another one. Because of these occasional introgressions, the genetic relationships between Corbicula species remained unclear, and the biogeographic origins of the invasive androgenetic lineages have been challenging to identify. To address these issues, we analyzed the patterns of allele sharing for several nuclear and mitochondrial molecular markers among Corbicula individuals collected across both the native and invasive range. Our results show the occurrence of an allelic pool encompassing all Corbicula freshwater species worldwide, including sexual and androgenetic ones, which highlights the substantial genetic mixing within this genus. However, the differences in allele sharing patterns between invasive lineages, and the low diversity within each lineage, suggest recent, distinct biogeographic origins of invasive Corbicula androgenetic lineages. Finally, the polyploidy, high heterozygosity, and hybrid phenotypes and genotypes found in our study probably originated from hybridization events following egg parasitism between distinct Corbicula lineages. This extensive cross-lineage mixing found in Corbicula may generate nuclear diversity in an otherwise asexually reproducing species.

Asymmetric Reciprocal Crossing Behavior of an Andean Blueberry (V.&amp;nbsp;meridionale) × Lingonberry (V.&amp;nbsp;vitis-idaea) Hybrid.

The fertility and crossing behavior of a tetraploid hybrid of 4x Andean blueberry (V.&amp;nbsp;meridionale) and lingonberry (V.&amp;nbsp;vitis-idaea) was evaluated through a series of crosses. Crosses of the hybrid with highbush blueberry produced divergent results. When used as a female with V.&amp;nbsp;corymbosum males, virtually all offspring were hexaploid, most likely arising from 2n = 4x = 48 female gametes, and 1n = 2x = 24 male gametes. However, when used as a male, tetraploid hybrids were produced, resulting from 1n = 2x = 24 gametes from each parent. To further examine this crossing behavior, the 4x&amp;nbsp;V. meridionale-V. vitis-idaea interspecific hybrid was pollinated with 6x&amp;nbsp;V.&amp;nbsp;virgatum (rabbiteye blueberry). Analogous to the previous crosses, 7x hybrids were produced from the joining of 2n = 4x = 48 female gametes with 1n = 3x = 36 male gametes. Such reciprocal crossing asymmetry is unprecedented. The ability to produce both 6x and 4x offspring from the same V.&amp;nbsp;corymbosum parents allows the potential of bridging a V.&amp;nbsp;meridionale hybrid genotype to both the tetraploid (V.&amp;nbsp;corymbosum) and hexaploid (V.&amp;nbsp;virgatum) commercial crop levels.

Hybridization drives mitochondrial DNA degeneration and metabolic shift in a species with biparental mitochondrial inheritance.

Mitochondrial DNA (mtDNA) is a cytoplasmic genome that is essential for respiratory metabolism. Although uniparental mtDNA inheritance is most common in animals and plants, distinct mtDNA haplotypes can coexist in a state of heteroplasmy, either because of paternal leakage or de novo mutations. mtDNA integrity and the resolution of heteroplasmy have important implications, notably for mitochondrial genetic disorders, speciation, and genome evolution in hybrids. However, the impact of genetic variation on the transition to homoplasmy from initially heteroplasmic backgrounds remains largely unknown. Here, we use Saccharomyces yeasts, fungi with constitutive biparental mtDNA inheritance, to investigate the resolution of mtDNA heteroplasmy in a variety of hybrid genotypes. We previously designed 11 crosses along a gradient of parental evolutionary divergence using undomesticated isolates of Saccharomyces paradoxus and Saccharomyces cerevisiae Each cross was independently replicated 48 to 96 times, and the resulting 864 hybrids were evolved under relaxed selection for mitochondrial function. Genome sequencing of 446 MA lines revealed extensive mtDNA recombination, but the recombination rate was not predicted by parental divergence level. We found a strong positive relationship between parental divergence and the rate of large-scale mtDNA deletions, which led to the loss of respiratory metabolism. We also uncovered associations between mtDNA recombination, mtDNA deletion, and genome instability that were genotype specific. Our results show that hybridization in yeast induces mtDNA degeneration through large-scale deletion and loss of function, with deep consequences for mtDNA evolution, metabolism, and the emergence of reproductive isolation.

Genetic diversity of whitefly species of the Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) species complex, associated with vegetable crops in Côte d'Ivoire.

Since several years, whiteflies of the species complex of Bemisia tabaci (Gennadius) are causing several damages on vegetable crops in Côte d'Ivoire. These sap-sucking insects are the main vector of many viruses on tomato and several species of this complex have developed resistances against insecticides. Nevertheless, there is very little information about whitefly species on vegetable crops in Côte d'Ivoire. Here, we investigated the species diversity and their genetic diversity and structuring on samples from vegetable crops in the major tomato production areas of Côte d'Ivoire. To assess this diversity, 535 whitefly samples from different localities and plant species were collected and analysed with nuclear (microsatellite) and mitochondrial (mtCOI) markers. In each site, and ecological data were recorded, including whiteflies abundance and plant species colonised by B. tabaci. The analysis of mtCOI sequences of whiteflies indicated the presence of four cryptic species on tomato and associated crops in Côte d'Ivoire. These were MED ASL, MED Q1, SSA 1 and SSA3. The MED ASL species dominated over all samples in the different regions and plant species. One haplotype of MED ASL out of the 15 identified predominated on most plant species and most sites. These results suggested that MED ASL is probably the main phytovirus vector in the Ivorian vegetable cropping areas. In contrast, only five haplotypes of MED Q1 were identified on vegetables but in the cotton-growing areas of the country. Its low prevalence, low nuclear and mitochondrial diversity might indicate a recent invasion of this species on vegetable crops in Côte d'Ivoire. The Bayesian nuclear analysis indicated the presence of hybrid genotypes between the two main species MED ASL and MED Q1, however in low prevalence (10%). All these results highlight the need to maintain whitefly populations monitoring for a more effective management in Côte d'Ivoire.

G×E Analysis of Early Growth Traits of Populus deltoides in East China by Using BLUP-GGE

In temperate and subtropical climates, Populus deltoides is an important poplar species. To analyze the stability, adaptability, and high yield of P. deltoides hybrid genotypes in East China, 38 P. deltoides genotypes were screened at three experimental sites in Shandong Province, and the coefficients of variation and genetic characteristics of 5-year growth were examined using BLUP-GGE. Results showed that all coefficients of variance were higher for diameter at breast height (DBH) than for tree height at all sites; the repeatability and heritability of tree height were greater than those of DBH at all sites. The fitting degree of tree height and DBH was 93.72% and 92.22%, respectively. The optimum genotype varied by location and grouping, of which Shanxian County divisions are the most powerful and representative of the three sites. The growth of 5-year-old P. deltoides was highly varied because of hereditary factors. Shanxian County is the more appropriate site for growth of P. deltoides in the tested sites in East China. In East China, genotypes 16, 5, 21, and 7 are regarded as superior. The genotypes 8, 26, and 36 are better for the site Rizhao; 16, 5, and 21 for site Shanxian; and 22, 21, and 5 for site Boxing.