Characteristics and Expression Analysis of <i>FmTCP15</i> under Abiotic Stresses and Hormones and Interact with DELLA Protein in <i>Fraxinus</i> <i>mandshurica</i> Rupr.

The TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATION CELL FACTOR (TCP) transcription factor is a plant-specific gene family and acts on multiple functional genes in controlling growth, development, stress response, and the circadian clock. In this study, a class I member of the TCP family from Fraxinus mandshurica Rupr. was isolated and named FmTCP15, which encoded a protein of 362 amino acids. Protein structures were analyzed and five ligand binding sites were predicted. The phylogenetic relationship showed that FmTCP15 was most closely related to Solanaceae and Plantaginaceae. FmTCP15 was localized in the nuclei of F. mandshurica protoplast cells and highly expressed in cotyledons. The expression pattern revealed the FmTCP15 response to multiple abiotic stresses and hormone signals. Downstream genes for transient overexpression of FmTCP15 in seedlings were also investigated. A yeast two-hybrid assay confirmed that FmTCP15 could interact with DELLA proteins. FmTCP15 participated in the GA-signaling pathway, responded to abiotic stresses and hormone signals, and regulated multiple genes in these biological processes. Our study revealed the potential value of FmTCP15 for understanding the molecular mechanisms of stress and hormone signal responses

Principal Component Analysis on the effect of media.

<p>Alt: <i>Alternaria</i> sp.; Pen: <i>Penicillium</i> sp.; Neu: <i>Neurospora</i> sp.; Cla: <i>Cladosporium</i> sp.; Phoma: <i>Phoma</i> sp.; Fus: <i>Fusarium</i> sp.; Phomo: <i>Pomopsis</i> sp.; Non: Pleosporales <i>Incertae Sedis</i> sp.; Tri: <i>Trichoderma</i> sp.; Epc: <i>Epicoccum</i> sp. Loadings over 0.7 were in bold.</p>*<p>:percentage of variance.</p>#<p>:Cumulative percentage.</p

Media effect on species isolated from <i>A. ginnala.</i>

<p>Alt: <i>Alternaria</i> sp.; Pen: <i>Penicillium</i> sp.; Neu: <i>Neurospora</i> sp.; Cla: <i>Cladosporium</i> sp.; Phoma: <i>Phoma</i> sp.; Fus: <i>Fusarium</i> sp.; Phomo: <i>Phomopsis</i> sp.; Non: Pleosporales <i>Incertae Sedis</i> sp.; Tri: <i>Trichoderma</i> sp.; Epc: <i>Epicoccum</i> sp.</p

Relative frequency of fungal endophytes from <i>A. ginnala</i>.

<p>Relative frequency (RF) means isolate frequency of a given endophyte divided by the sum of isolate frequencies of all endophytes×100.</p

Colonization and isolation frequency of fungal endophytes from <i>A. ginnala.</i>

<p>Colonization and isolation frequency of fungal endophytes from <i>A. ginnala.</i></p

Clustal analysis of tissues.

<p>The dendrogram was drawn by PAST with Bray-Curtis’s similarity. The numbers on the branches were the support percentage from10000 bootstraps.</p

α diversity indices and bootstrapping comparison between tissues.

<p>Whole tree represented by Bark + Xylem + Seed + Annual twig while perennial twig by Bark +Xylem.</p

Interspecific hybridizations of Fraxinus L. (F. mandshurica × F. americana and F. mandshurica × F. velutina) and heterosis analysis and selection of F1 progenies

The interspecific hybridizations of Fraxinus mandshurica Rupr. × Fraxinus americana L. (MA) and Fraxinus mandshurica × Fraxinus velutina Torr. (MV) were conducted to solve the problems of poor cold adaption associated with the introduction of Fraxinus in Heilongjiang province. High-voltage electrostatic field (HVEF) treatment to pollen was performed to overcome the prefertilization barriers. The hybrids adapted more strongly and grew better than the pure species (heterosis over higher parent (HHP) of the 9-year volume index was 5.5% for MA and 23.1% for MV) in Heilongjiang province. HVEF treatment greatly improved the number of seeds (0.25- to 5.52-fold) and seedlings (1.63- to 8.71-fold) of the hybrids. Additionally, three excellent female parents (nos. 15, 16, and 17) and seven hybrid combinations of MA (D94, D70, and D100) and MV (D103, D116, D105, and D104) with excellent growth traits were selected. The HHPs of volume index were 39.1%–112.5% for selected hybrids. Additionally, predicted growth trends of the hybrids showed that the hybrids will maintain a 7.7% to 9.3% height advantage over F. mandshurica through ages 10 to 15 years in Mao Ershan. These findings will accelerate the genetic breeding process of Fraxinus species.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author