Dissecting the genetic architecture of flowering and maturity time in almond (Prunus dulcis): heritability estimates and breeding value predictions from historical data
Authors: GOMEZ ABAJO, M. D. M., Dicenta, F., Martinez-Garcia, P. J.
The study estimated genetic parameters for flowering and maturity time in almond (Prunus dulcis) using classical segregation analyses and Bayesian linear mixed models on a pedigree of over 17,500 individuals spanning 30 years. Heritability and repeatability were quantified, breeding values (EBVs) were computed for all genotypes, and trait-specific rankings were generated to improve parental selection. The results provide a foundation for integrating genomic selection into almond breeding programs.
The study used comparative transcriptomics across Erysimum species to identify two 2‑oxoglutarate‑dependent dioxygenases, CARD5 and CARD6, responsible for the 14β‑ and 21‑hydroxylation steps in cardenolide biosynthesis in Erysimum cheiranthoides. Knockout mutants lacking these genes accumulated pathway intermediates, and transient expression in Nicotiana benthamiana confirmed their enzymatic functions, while structural modeling pinpointed residues linked to neofunctionalization.
Comparative transcriptomics uncovers plant and fungal genetic determinants of mycorrhizal compatibility
Authors: Marques-Galvez, J. E., de Freitas Pereira, M., Nehls, U., Ruytinx, J., Barry, K., Peter, M., Martin, F., Grigoriev, I. V., Veneault-Fourrey, C., Kohler, A.
The study used comparative and de‑novo transcriptomic analyses in poplar to uncover plant and fungal gene regulons that govern ectomycorrhizal (ECM) compatibility, distinguishing general fungal‑sensing responses from ECM‑specific pathways. Key findings include modulation of jasmonic acid‑related defenses, coordinated regulation of secretory and cell‑wall remodeling genes, and dynamic expression of the Common Symbiosis Pathway during early and mature symbiosis stages.
High radiosensitivity in the conifer Norway spruce (Picea abies) due to lesscomprehensive mobilisation of protection and repair responses compared to the radiotolerant Arabidopsis thaliana
Authors: Bhattacharjee, P., Blagojevic, D., Lee, Y., Gillard, G. B., Gronvold, L., Hvidsten, T. R., Sandve, S. R., Lind, O. C., Salbu, B., Brede, D. A., Olsen, J. E.
The study compared early protective, repair, and stress responses to chronic gamma irradiation in the radiosensitive conifer Norway spruce (Picea abies) and the radiotolerant Arabidopsis thaliana. Norway spruce exhibited growth inhibition, mitochondrial damage, and higher DNA damage at low dose rates, while Arabidopsis maintained growth, showed minimal organelle damage, and activated DNA repair and antioxidant genes even at the lowest dose rates. Transcriptomic analysis revealed that the tolerant species mounts a robust transcriptional response at low doses, whereas the sensitive species only responds at much higher doses.
The study models maize flowering time plasticity using a physiological reaction norm derived from multi-environment trial data, revealing genotype-specific differences in temperature-driven development and photoperiod perception. It introduces an envirotyping metric that shows genotypes can experience markedly different photoperiods even within the same environment, and demonstrates distinct adaptive strategies between tropical and temperate germplasm.
The study identifies RAF24, a B4 Raf-like MAPKKK, as a novel regulator of flowering time in Arabidopsis, demonstrating that RAF24 controls the phosphorylation of the ubiquitin ligase HUB2 via SnRK2 kinases, thereby modulating H2Bub1 levels. Phospho‑mimetic and phospho‑ablative HUB2 mutants confirm that phosphorylation at S314 is critical for proper flowering timing.
The study used comparative transcriptomics to examine how Fusarium oxysporum isolates with different lifestyles on angiosperms regulate effector genes during infection of the non‑vascular liverwort Marchantia polymorpha. Core effector genes on fast core chromosomes are actively expressed in the bryophyte host, while lineage‑specific effectors linked to angiosperm pathogenicity are silent, and disruption of a compatibility‑associated core effector alters the expression of other core effectors, highlighting conserved fungal gene networks across plant lineages.
The study investigates how cytosine methylation influences flowering time under drought stress in Arabidopsis thaliana, using the drm1 drm2 cmt3 triple mutant (ddc). Drought delayed flowering by one day in wild type but two days in ddc, coinciding with overexpression of BBX16/COL7 and BBX17/COL8 and down‑regulation of NF‑YA2, suggesting a trans‑acting methylation‑dependent regulatory network affecting FT induction.
The study generated a high-quality genome assembly for Victoria cruziana and used comparative transcriptomics to identify anthocyanin biosynthesis genes and their transcriptional regulators that are differentially expressed between white and light pinkish flower stages. Differential expression of structural genes (VcrF3H, VcrF35H, VcrDFR, VcrANS, VcrarGST) and transcription factors (VcrMYB123, VcrMYB-SG6_a, VcrMYB-SG6_b, VcrTT8, VcrTTG1) correlates with the observed flower color change.
The study investigates how miR394 influences flowering time in Arabidopsis thaliana by combining transcriptomic profiling of mir394a mir394b double mutants with histological analysis of reporter lines. Bioinformatic analysis identified a novel lncRNA overlapping MIR394B (named MIRAST), and differential promoter activity of MIR394A and MIR394B suggests miR394 fine‑tunes flower development through transcription factor and chromatin remodeler regulation.