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Plants (Basel, Switzerland) Jun 2024An initial cross of 'Johnblue' (Darrow's blueberry) × 'Red Sunset' (lingonberry) produced more than 30 true intersectional diploid hybrids as confirmed by molecular...
An initial cross of 'Johnblue' (Darrow's blueberry) × 'Red Sunset' (lingonberry) produced more than 30 true intersectional diploid hybrids as confirmed by molecular markers. The most vigorous of these hybrids was extensively evaluated. This hybrid, US 2535-A, was floriferous and morphologically intermediate to the respective parents. Examination of pollen suggested low male fertility. Numerous crosses using the hybrid as a female reflected similarly low fertility and potential crossing barriers. Stylar examination suggested blockage of pollen tube growth in self-pollinations and significantly retarded growth in backcross pollinations. Nonetheless, two confirmed hybrid offspring were produced using the F hybrid as a female in crosses with and , respectively. In a second set of crosses utilizing additional and genotypes, another 23 verified hybrids in seven parental combinations were produced. Hybrids such as the ones presented offer the potential for generating de novo interspecific fruit types in blueberry and/or broadening the adaptation of lingonberry.
PubMed: 38891380
DOI: 10.3390/plants13111572 -
Plants (Basel, Switzerland) Jun 2024The Dwarf Palm, Deble & Marchiori, is an endangered species endemic to the Pampa biome and typically grows in sandy and rocky soils. Given its economic, ecological, and...
The Dwarf Palm, Deble & Marchiori, is an endangered species endemic to the Pampa biome and typically grows in sandy and rocky soils. Given its economic, ecological, and cultural relevance, it is crucial to understand the ecology and biology of this species to encourage its preservation and highlight its significance for the Pampa. This study aims to investigate whether this palm relies on animal vectors for pollination, analyze its breeding system, and propose strategies for its conservation and sustainable use. We conducted field observations on pollination ecology, identified floral visitors, and designed six breeding system experiments to test cross-compatibility, self-compatibility, and apomixis. Additionally, we conducted a literature review to propose conservation strategies. is pollinator-dependent and self-compatible. The flowers are mostly melittophilous and offer pollen and nectar for floral visitors. The main pollinators are native Meliponinae and Halictinae bees and the introduced . This study represents the first comprehensive and complete examination of the breeding system and pollination process on palms. This palm can provide materials for industries, but urgent actions are needed to preserve the remaining populations through effective policies and strategies. Furthermore, this palm should be integrated into diversified agroecosystems to evaluate its adaptability to cultivation.
PubMed: 38891370
DOI: 10.3390/plants13111562 -
Plants (Basel, Switzerland) May 2024The use of dwarf plants in tomato breeding has provided several advantages. However, there are no identified dwarf plants () containing the self-pruning habit (). The...
The use of dwarf plants in tomato breeding has provided several advantages. However, there are no identified dwarf plants () containing the self-pruning habit (). The aim of this work was to obtain future generations, characterize the germplasm, and select potential dwarf plants with a determinate growth habit to obtain Salad-type lines. The work was started by carrying out hybridization, followed by the first, second, and third backcrosses. Once FBC seeds became available, the introgression of the self-pruning gene () into dwarf plants () began. Three strains of normal architecture and a determinate growth habit were hybridized with two strains of dwarf size and an indeterminate growth habit, thus yielding four hybrids. Additionally, donor genotype UFU MC TOM1, the commercial cultivar Santa Clara, and the wild accession were used in the experiment. Agronomic traits, fruit quality, metabolomics, and acylsugars content were evaluated, and dwarf plants with a determinate growth habit were selected. Hybrid 3 exhibited the highest yields. Visual differences between determinate and indeterminate dwarf plant seedlings were observed. It is suggested to carry out five self-pollinations of the best dwarf plant determined and subsequent hybridization with homozygous lines of normal plant architecture and determinate growth habit to obtain hybrids.
PubMed: 38891329
DOI: 10.3390/plants13111522 -
Plants (Basel, Switzerland) May 2024Pollination in angiosperms depends on complex communication between pollen grains and stigmas, classified as wet or dry, depending on the presence or absence of...
Pollination in angiosperms depends on complex communication between pollen grains and stigmas, classified as wet or dry, depending on the presence or absence of secretions at the stigma surface, respectively. In species with wet stigma, the cuticle is disrupted and the presence of exudates is indicative of their receptivity. Most stigma studies are focused on a few species and families, many of them with self-incompatibility systems. However, there is scarce knowledge about the stigma composition in Fabaceae, the third angiosperm family, whose stigmas have been classified as semidry. Here we report the first transcriptome profiling and DEGs of L. styles and stigmas from autofertile (flowers able to self-fertilize in the absence of manipulation, whose exudate is released spontaneously) and autosterile (flowers that need to be manipulated to break the cuticle and release the exudates to be receptive) inbred lines. From the 76,269 contigs obtained from the de novo assembly, only 45.1% of the sequences were annotated with at least one GO term. A total of 115,920, 75,489, and 70,801 annotations were assigned to Biological Process (BP), Cellular Component (CC), and Molecular Function (MF) categories, respectively, and 5918 differentially expressed genes (DEGs) were identified between the autofertile and the autosterile lines. Among the most enriched metabolic pathways in the DEGs subset were those related with amino acid biosynthesis, terpenoid metabolism, or signal transduction. Some DEGs have been related with previous QTLs identified for autofertility traits, and their putative functions are discussed. The results derived from this work provide an important transcriptomic reference for style-stigma processes to aid our understanding of the molecular mechanisms involved in faba bean fertilization.
PubMed: 38891252
DOI: 10.3390/plants13111443 -
Scientific Reports Jun 2024Biological invasions threaten global biodiversity, altering landscapes, ecosystems, and mutualistic relationships like pollination. Orchids are one of the most...
Biological invasions threaten global biodiversity, altering landscapes, ecosystems, and mutualistic relationships like pollination. Orchids are one of the most threatened plant families, yet the impact of invasive bees on their reproduction remains poorly understood. We conduct a global literature survey on the incidence of invasive honeybees (Apis mellifera) on orchid pollination, followed by a study case on Australian orchids. Our literature survey shows that Apis mellifera is the primary alien bee visiting orchids worldwide. However, in most cases, introduced honeybees do not deposit orchid pollen. We also test the extent to which introduced honeybees affect orchid pollination using Diuris brumalis and D. magnifica. Diuris brumalis shows higher fruit set and pollination in habitats with both native and invasive bees compared to habitats with only introduced bees. Male and female reproductive success in D. magnifica increases with native bee abundance, while conversely pollinator efficiency decreases with honeybee abundance and rises with habitat size. Our results suggest that introduced honeybees are likely involved in pollen removal but do not effectively deposit orchid pollen, acting as pollen wasters. However, Apis mellifera may still contribute to pollination of Diuris where native bees no longer exist. Given the global occurrence of introduced honeybees, we warn that certain orchids may suffer from pollen depletion by these invaders, especially in altered habitats with compromised pollination communities.
Topics: Animals; Bees; Pollination; Orchidaceae; Pollen; Introduced Species; Ecosystem; Male; Reproduction; Australia; Female
PubMed: 38890342
DOI: 10.1038/s41598-024-64218-x -
Nature Communications Jun 2024Although different ecological factors shape adaptative evolution in natural habitats, we know little about how their interactions impact local adaptation. Here we used...
Although different ecological factors shape adaptative evolution in natural habitats, we know little about how their interactions impact local adaptation. Here we used eight generations of experimental evolution with outcrossing Brassica rapa plants as a model system, in eight treatment groups that varied in soil type, herbivory (with/without aphids), and pollination mode (hand- or bumblebee-pollination), to study how biotic interactions affect local adaptation to soil. First, we show that several plant traits evolved in response to biotic interactions in a soil-specific way. Second, using a reciprocal transplant experiment, we demonstrate that significant local adaptation to soil-type evolved in the "number of open flowers", a trait used as a fitness proxy, but only in plants that evolved with herbivory and bee pollination. Whole genome re-sequencing of experimental lines revealed that biotic interactions caused a 10-fold increase in the number of SNPs across the genome with significant allele frequency change, and that alleles with opposite allele frequency change in different soil types (antagonistic pleiotropy) were most common in plants with an evolutionary history of herbivory and bee pollination. Our results demonstrate that the interaction with mutualists and antagonists can facilitate local adaptation to soil type through antagonistic pleiotropy.
Topics: Pollination; Soil; Animals; Herbivory; Brassica rapa; Bees; Adaptation, Physiological; Polymorphism, Single Nucleotide; Biological Evolution; Flowers; Gene Frequency; Aphids; Ecosystem
PubMed: 38890322
DOI: 10.1038/s41467-024-49383-x -
Proceedings. Biological Sciences Jun 2024Stebbins hypothesized that selfing lineages are evolutionary dead ends because they lack adaptive potential. While selfing populations often possess limited nucleotide...
Stebbins hypothesized that selfing lineages are evolutionary dead ends because they lack adaptive potential. While selfing populations often possess limited nucleotide variability compared with closely related outcrossers, reductions in the genetic variability of quantitative characters remain unclear, especially for key traits determining selfing rates. Yellow monkeyflower () populations generally outcross and maintain extensive quantitative genetic variation in floral traits. Here, we study the Joy Road population (Bodega Bay, CA, USA) of , where individuals exhibit stigma-anther distances (SAD) typical of primarily selfing monkeyflowers. We show that this population is closely related to nearby conspecifics on the Pacific Coast with a modest 33% reduction in genome-wide variation compared with a more highly outcrossing population. A five-generation artificial selection experiment challenged the hypothesis that the Joy Road population harbours comparatively low evolutionary potential in stigma-anther distance, a critical determinant of selfing rate in . Artificial selection generated a weak phenotypic response, with low realized heritabilities (0.020-0.028) falling 84% below those measured for floral characters in more highly outcrossing . These results demonstrate substantial declines in evolutionary potential with a transition toward selfing. Whether these findings explain infrequent reversals to outcrossing or general limits on adaptation in selfers requires further investigation.
Topics: Mimulus; Flowers; Selection, Genetic; Biological Evolution; Pollination; Genetic Variation; California; Self-Fertilization; Phenotype
PubMed: 38889787
DOI: 10.1098/rspb.2024.0586 -
Proceedings. Biological Sciences Jun 2024Extreme heat poses a major threat to plants and pollinators, yet the indirect consequences of heat stress are not well understood, particularly for native solitary bees....
Extreme heat poses a major threat to plants and pollinators, yet the indirect consequences of heat stress are not well understood, particularly for native solitary bees. To determine how brief exposure of extreme heat to flowering plants affects bee behaviour, fecundity, development and survival we conducted a no-choice field cage experiment in which were provided blueberry (), phacelia () and white clover () that had been previously exposed to either extreme heat (37.5°C) or normal temperatures (25°C) for 4 h during early bloom. Despite a similar number of open flowers and floral visitation frequency between the two treatments, female bees provided with heat-stressed plants laid approximately 70% fewer eggs than females provided with non-stressed plants. Their progeny received similar quantities of pollen provisions between the two treatments, yet larvae consuming pollen from heat-stressed plants had significantly lower survival as larvae and adults. We also observed trends for delayed emergence and reduced adult longevity when larvae consumed heat-stressed pollen. This study is the first to document how short, field-realistic bursts of extreme heat exposure to flowering host plants can indirectly affect bee pollinators and their offspring, with important implications for crop pollination and native bee populations.
Topics: Animals; Bees; Fertility; Pollination; Female; Extreme Heat; Hot Temperature; Longevity; Pollen
PubMed: 38889783
DOI: 10.1098/rspb.2024.0714 -
Biology Letters Jun 2024Floral longevity, the length of time a flower remains open and functional, is a phylogenetically conserved trait that balances floral costs against the rate at which...
Floral longevity, the length of time a flower remains open and functional, is a phylogenetically conserved trait that balances floral costs against the rate at which flowers are pollinated. Floral symmetry has long been considered a key trait in floral evolution. Although zygomorphic (bilaterally symmetric) flowers typically receive fewer floral visitors than actinomorphic (radially symmetric) flowers, it is yet to be determined whether this could be associated with longer floral longevity. Using newly collected field data combined with data from the literature on 1452 species in 168 families, we assess whether floral longevity covaries with floral symmetry in a phylogenetic framework. We find that zygomorphic flowers last on average 1.1 days longer than actinomorphic flowers, a 26.5% increase in longevity, with considerable variation across both groups. Our results provide a basis to discuss the ecological and evolutionary costs of zygomorphy for plants. Despite these costs, zygomorphy has evolved numerous times throughout angiosperm history, and we discuss which rewards may outweigh the costs of slower pollination in zygomorphic flowers.
Topics: Flowers; Biological Evolution; Pollination; Magnoliopsida; Phylogeny
PubMed: 38889773
DOI: 10.1098/rsbl.2024.0082 -
Current Biology : CB Jun 2024Painted ladies are well-known migratory butterflies, but confirmation of the details of their swarming flights through Europe has evaded scientists until now. It was...
Painted ladies are well-known migratory butterflies, but confirmation of the details of their swarming flights through Europe has evaded scientists until now. It was their role as pollinators, carrying pollen grains on their flights, that helped unlock the secrets of their migrations.
Topics: Animals; Butterflies; Pollen; Animal Migration; Pollination; Europe; Flight, Animal
PubMed: 38889675
DOI: 10.1016/j.cub.2024.05.002