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Genes Jun 2024An appropriate flowering period is an important selection criterion in maize breeding. It plays a crucial role in the ecological adaptability of maize varieties. To...
An appropriate flowering period is an important selection criterion in maize breeding. It plays a crucial role in the ecological adaptability of maize varieties. To explore the genetic basis of flowering time, GWAS and GS analyses were conducted using an associating panel consisting of 379 multi-parent DH lines. The DH population was phenotyped for days to tasseling (DTT), days to pollen-shedding (DTP), and days to silking (DTS) in different environments. The heritability was 82.75%, 86.09%, and 85.26% for DTT, DTP, and DTS, respectively. The GWAS analysis with the FarmCPU model identified 10 single-nucleotide polymorphisms (SNPs) distributed on chromosomes 3, 8, 9, and 10 that were significantly associated with flowering time-related traits. The GWAS analysis with the BLINK model identified seven SNPs distributed on chromosomes 1, 3, 8, 9, and 10 that were significantly associated with flowering time-related traits. Three SNPs 3_198946071, 9_146646966, and 9_152140631 showed a pleiotropic effect, indicating a significant genetic correlation between DTT, DTP, and DTS. A total of 24 candidate genes were detected. A relatively high prediction accuracy was achieved with 100 significantly associated SNPs detected from GWAS, and the optimal training population size was 70%. This study provides a better understanding of the genetic architecture of flowering time-related traits and provides an optimal strategy for GS.
Topics: Zea mays; Genome-Wide Association Study; Polymorphism, Single Nucleotide; Flowers; Phenotype; Quantitative Trait Loci; Plant Breeding; Selection, Genetic; Genome, Plant; Chromosomes, Plant
PubMed: 38927676
DOI: 10.3390/genes15060740 -
Genes Jun 2024The citrus cultivar 'Local Juhong', which has historically been used as a traditional Chinese medicinal material, originated in Yuanjiang County, Hunan Province.Its...
The citrus cultivar 'Local Juhong', which has historically been used as a traditional Chinese medicinal material, originated in Yuanjiang County, Hunan Province.Its parental type and genetic background are indistinct as of yet. Morphological observation shows that 'Local Juhong' has a slight oblateness in fruit shape, a relatively smooth pericarp, a fine and slightly raised oil vacuole, and an inward concave at the blossom end. The tree form and fruit and leaf morphology of 'Local Juhong' are similar to those of 'Huangpi' sour orange. To reveal the genetic background of 'Local Juhong', 21 citrus accessions were evaluated using nuclear and chloroplast SSR markers and whole-genome SNP information. 'Local Juhong' was grouped with mandarins and sub-grouped with 'Miyagawa Wase' and 'Yanxi Wanlu' in a nuclear SSR analysis, which indicated that its pollen parent might be mandarins. It was closely clustered with orange and pummelo in the chloroplast SSR analysis. The genomic sequence similarity rate of 'Local Juhong' with mandarin and pummelo heterozygosity was 70.88%; the main part was the heterozygosity, except for the unknown (19.66%), mandarin (8.73%), and pummelo (3.9%) parts. Thus, 'Local Juhong' may be an F hybrid with pummelo as the female parent and mandarin as the male parent, sharing sisterhood with 'Huangpi' sour orange.
Topics: Citrus; Microsatellite Repeats; Polymorphism, Single Nucleotide; Plants, Medicinal; Genomics; Genome, Plant; Genetic Markers; Phylogeny; Chloroplasts
PubMed: 38927655
DOI: 10.3390/genes15060719 -
Identification, Elucidation and Deployment of a Cytoplasmic Male Sterility System for Hybrid Potato.Biology Jun 2024Recent advances in diploid F hybrid potato breeding rely on the production of inbred lines using the () gene. As a result of this method, female parent lines are...
Recent advances in diploid F hybrid potato breeding rely on the production of inbred lines using the () gene. As a result of this method, female parent lines are self-fertile and require emasculation before hybrid seed production. The resulting F hybrids are self-fertile as well and produce many undesirable berries in the field. Utilization of cytoplasmic male sterility would eliminate the need for emasculation, resulting in more efficient hybrid seed production and male sterile F hybrids. We observed plants that completely lacked anthers in an F population derived from an interspecific cross between diploid and . We studied the trait to determine its suitability for use in hybrid potato breeding. We mapped the causal locus to the short arm of Chromosome 6, developed KASP markers for the () locus and introduced it into lines with T and A cytoplasm. We found that type male sterility is not expressed in T and A cytoplasm, proving that it is a form of CMS. We hybridized male sterile plants with P cytoplasm with pollen from plants with T and A cytoplasm and we show that the resulting hybrids set significantly fewer berries in the field. Here, we show that the antherless CMS system can be readily deployed in diploid F hybrid potato breeding to improve hybridization efficiency and reduce berry set in the field.
PubMed: 38927327
DOI: 10.3390/biology13060447 -
Biology Jun 2024Pollinators are needed for the reproduction of , and only sphingid moths have mouthparts long enough to reach the nectar at the bottom of the species' long, twisted...
Pollinators are needed for the reproduction of , and only sphingid moths have mouthparts long enough to reach the nectar at the bottom of the species' long, twisted floral tube. Though plants produce many flowers over a period of several months, one observes very few fruits in nature. We asked: (1) Are plants self-compatible, or do they need pollen from another individual to set fruit and seed? (2) Are cross-pollinations between unrelated individuals more successful than crosses with relatives? (3) How does the relatedness of pollen and ovule parent plants affect fruit set, seed number, and seed quality? We investigated the breeding system of by collecting fruits from seven sites, growing plants and performing hand pollinations over a period of several years, collecting and measuring fruits and counting seeds. is self-incompatible, though some individuals produce fruit by self-pollination. Cross-pollinations between unrelated individuals set the most fruit (59%), and those that were self-pollinated set the least (9%). Fruit set from cross-pollinations between related individuals was intermediate (32%). Although the number of seeds per fruit did not differ significantly among pollination treatments, fruits from self-pollinations had substantially fewer viable seeds than outcrossed fruits, with fruits from sibling crosses being intermediate. There were higher levels of self-compatibility in the fragment populations compared with plants from intact habitats. Self-incompatibility may explain why fruit set is low in this plant species; future investigation into the breakdown of self-incompatibility in smaller populations is warranted.
PubMed: 38927303
DOI: 10.3390/biology13060423 -
BMC Plant Biology Jun 2024During male gametogenesis of flowering plants, sperm cell lineage (microspores, generative cells, and sperm cells) differentiated from somatic cells and acquired...
BACKGROUND
During male gametogenesis of flowering plants, sperm cell lineage (microspores, generative cells, and sperm cells) differentiated from somatic cells and acquired different cell fates. Trimethylation of histone H3 on lysine 4 (H3K4me3) epigenetically contributes to this process, however, it remained unclear how H3K4me3 influences the gene expression in each cell type. Here, we conducted chromatin immunoprecipitation sequencing (ChIP-seq) to obtain a genome-wide landscape of H3K4me3 during sperm cell lineage development in tomato (Solanum lycopersicum).
RESULTS
We show that H3K4me3 peaks were mainly enriched in the promoter regions, and intergenic H3K4me3 peaks expanded as sperm cell lineage differentiated from somatic cells. H3K4me3 was generally positively associated with transcript abundance and served as a better indicator of gene expression in somatic and vegetative cells, compared to sperm cell lineage. H3K4me3 was mutually exclusive with DNA methylation at 3' proximal of the transcription start sites. The microspore maintained the H3K4me3 features of somatic cells, while generative cells and sperm cells shared an almost identical H3K4me3 pattern which differed from that of the vegetative cell. After microspore division, significant loss of H3K4me3 in genes related to brassinosteroid and cytokinin signaling was observed in generative cells and vegetative cells, respectively.
CONCLUSIONS
Our results suggest the asymmetric division of the microspore significantly reshapes the genome-wide distribution of H3K4me3. Selective loss of H3K4me3 in genes related to hormone signaling may contribute to functional differentiation of sperm cell lineage. This work provides new resource data for the epigenetic studies of gametogenesis in plants.
Topics: Solanum lycopersicum; Histones; Cell Lineage; Genome, Plant; DNA Methylation; Gene Expression Regulation, Plant; Pollen; Epigenesis, Genetic; Chromatin Immunoprecipitation Sequencing
PubMed: 38926660
DOI: 10.1186/s12870-024-05318-8 -
Journal of Molecular Evolution Jun 2024Kinesins are eukaryotic microtubule motor proteins subdivided into conserved families with distinct functional roles. While many kinesin families are widespread in...
Kinesins are eukaryotic microtubule motor proteins subdivided into conserved families with distinct functional roles. While many kinesin families are widespread in eukaryotes, each organismal lineage maintains a unique kinesin repertoire composed of many families with distinct numbers of genes. Previous genomic surveys indicated that land plant kinesin repertoires differ markedly from other eukaryotes. To determine when repertoires diverged during plant evolution, we performed robust phylogenomic analyses of kinesins in 24 representative plants, two algae, two animals, and one yeast. These analyses show that kinesin repertoires expand and contract coincident with major shifts in the biology of algae and land plants. One kinesin family and five subfamilies, each defined by unique domain architectures, emerged in the green algae. Four of those kinesin groups expanded in ancestors of modern land plants, while six other kinesin groups were lost in the ancestors of pollen-bearing plants. Expansions of different kinesin families and subfamilies occurred in moss and angiosperm lineages. Other kinesin families remained stable and did not expand throughout plant evolution. Collectively these data support a radiation of kinesin domain architectures in algae followed by differential positive and negative selection on kinesins families and subfamilies in different lineages of land plants.
PubMed: 38926179
DOI: 10.1007/s00239-024-10178-9 -
Current Biology : CB Jun 2024Foraging behavior frequently plays a major role in driving the geographic distribution of animals. Buzzing to extract protein-rich pollen from flowers is a key foraging...
Foraging behavior frequently plays a major role in driving the geographic distribution of animals. Buzzing to extract protein-rich pollen from flowers is a key foraging behavior used by bee species across at least 83 genera (these genera comprise ∼58% of all bee species). Although buzzing is widely recognized to affect the ecology and evolution of bees and flowering plants (e.g., buzz-pollinated flowers), global patterns and drivers of buzzing bee biogeography remain unexplored. Here, we investigate the global species distribution patterns within each bee family and how patterns and drivers differ with respect to buzzing bee species. We found that both distributional patterns and drivers of richness typically differed for buzzing species compared with hotspots for all bee species and when grouped by family. A major predictor of the distribution, but not species richness overall for buzzing members of four of the five major bee families included in analyses (Andrenidae, Halictidae, Colletidae, and to a lesser extent, Apidae), was the richness of poricidal flowering plant species, which depend on buzzing bees for pollination. Because poricidal plant richness was highest in areas with low wind and high aridity, we discuss how global hotspots of buzzing bee biodiversity are likely influenced by both biogeographic factors and plant host availability. Although we explored global patterns with state-level data, higher-resolution work is needed to explore local-level drivers of patterns. From a global perspective, buzz-pollinated plants clearly play a greater role in the ecology and evolution of buzzing bees than previously predicted.
PubMed: 38925116
DOI: 10.1016/j.cub.2024.05.065 -
Physiologia Plantarum 2024During microspore embryogenesis, microspores are induced to develop into haploid embryos. In Brassica napus, microspore embryogenesis is induced by a heat shock (HS),...
The different response of Brassica napus genotypes to microspore embryogenesis induced by heat shock and trichostatin A is not determined by changes in cell wall structure and composition but by different stress tolerance.
During microspore embryogenesis, microspores are induced to develop into haploid embryos. In Brassica napus, microspore embryogenesis is induced by a heat shock (HS), which initially produces embryogenic structures with different cell wall architectures and compositions, and with different potentials to develop into embryos. The B. napus DH4079 and DH12075 genotypes have high and very low embryo yields, respectively. In DH12075, embryo yield is greatly increased by combining HS and the histone deacetylase (HDAC) inhibitor trichostatin A (TSA). However, we show that HS + TSA inhibits embryogenesis in the highly embryogenic DH4079 line. To ascertain why TSA has such different effects in these lines, we treated DH4079 and DH12075 microspore cultures with TSA and compared the cell wall structure and composition of the different embryogenic structures in both lines, specifically the in situ levels and distribution of callose, cellulose, arabinogalactan proteins and high and low methyl-esterified pectin. For both lines, HS + TSA led to the formation of cell walls unfavorable for embryogenesis progression, with reduced levels of arabinogalactan proteins, reduced cell adhesion of inner walls and altered pectin composition. Thus, TSA effects on cell walls cannot explain their different embryogenic response to TSA. We also applied TSA to DH4079 cultures at different times and concentrations before HS application, with no negative effects on embryogenic induction. These results indicate that DH4079 microspores are hypersensitive to combined TSA and HS treatments, and open up new hypotheses about the causes of such hypersensitivity.
Topics: Brassica napus; Cell Wall; Hydroxamic Acids; Heat-Shock Response; Genotype; Pollen; Stress, Physiological
PubMed: 38923567
DOI: 10.1111/ppl.14405 -
Allergy Jun 2024
PubMed: 38923532
DOI: 10.1111/all.16211 -
Plant Physiology Jun 2024The intricate process of male gametophyte development in flowering plants is regulated by jasmonic acid (JA) signaling. JA signaling initiates with the activation of the...
The intricate process of male gametophyte development in flowering plants is regulated by jasmonic acid (JA) signaling. JA signaling initiates with the activation of the basic-helix-loop-helix (bHLH) transcription factor (TF), MYC2, leading to the expression of numerous JA-responsive genes during stamen development and pollen maturation. However, the regulation of JA signaling during different stages of male gametophyte development remains less understood. This study focuses on the characterization of the plant ARID-HMG DNA-BINDING PROTEIN 15 (AtHMGB15), and its role in pollen development in Arabidopsis (Arabidopsis thaliana). Phenotypic characterization of a T-DNA insertion line (athmgb15-4) revealed delayed bolting, shorter siliques, and reduced seed set in mutant plants compared to the wildtype. Additionally, AtHMGB15 deletion resulted in defective pollen morphology, delayed pollen germination, aberrant pollen tube growth, and a higher percentage of non-viable pollen grains. Molecular analysis indicated the down-regulation of JA biosynthesis and signaling genes in the athmgb15-4 mutant. Quantitative analysis demonstrated that jasmonic acid and its derivatives were approximately tenfold lower in athmgb15-4 flowers. Exogenous application of methyl jasmonate could restore pollen morphology and germination, suggesting that the low JA content in athmgb15-4 impaired JA signaling during pollen development. Furthermore, our study revealed that AtHMGB15 physically interacts with MYC2 to form a transcription activation complex. This complex promotes the transcription of key JA signaling genes, the R2R3-MYB TFs MYB21 and MYB24, during stamen and pollen development. Collectively, our findings highlight the role of AtHMGB15 as a positive regulator of the JA pathway, controlling the spatiotemporal expression of key regulators involved in Arabidopsis stamen and pollen development.
PubMed: 38922580
DOI: 10.1093/plphys/kiae355