The genetic architecture of leaf vein density traits and its importance for photosynthesis in maize
Authors: Coyac-Rodriguez, J. L., Perez-Limon, S., Hernandez-Jaimes, E., Hernandez-Coronado, M., Camo-Escobar, D., Alonso-Nieves, A. L., Ortega-Estrada, M. d. J., Gomez-Capetillo, N., Sawers, R. J., Ortiz-Ramirez, C. H.
Using diverse Mexican maize varieties and a MAGIC population, the study demonstrated that leaf vein density is both variable and plastic, correlating positively with photosynthetic rates for small intermediate veins and increasing under heat in drought-adapted lines. Twelve QTLs linked to vein patterning were identified, highlighting candidate genes for intermediate vein development and shedding light on the evolution of high-efficiency C4 leaf architecture.
The study examined how elevated atmospheric CO₂ (550 ppm) affects immunity in the C₄ cereal maize (Zea mays L.) by exposing plants grown under ambient and elevated CO₂ to a range of pathogens. Elevated CO₂ increased susceptibility to sugarcane mosaic virus, decreased susceptibility to several bacterial and fungal pathogens, and left susceptibility to others unchanged, with reduced bacterial disease linked to heightened basal immune responses. These findings provide a baseline for future investigations into CO₂‑responsive defense mechanisms in C₄ crops.
The study reveals that REMORIN protein evolution is primarily driven by diversification of their conserved C-terminal domain, defining four major clades. Structural bioinformatics predicts a common membrane‑binding interface with diverse curvatures and lengths, and suggests that some REMs can form C‑terminal‑mediated oligomers, adding complexity to membrane organization.
The study evaluated how stomatal anatomy and physiological efficiency influence wheat heat tolerance across multi‑environment field trials with 200 genotypes, using early versus delayed sowing to impose temperature stress. Findings revealed a decoupling between anatomical capacity (gsmax) and actual conductance (gs, gse) under heat, plastic shifts toward smaller, denser stomata, and identified 125 QTL linked to stomatal traits, suggesting targets for breeding climate‑resilient wheat.
The study examined how DNA methylation influences cold stress priming in Arabidopsis thaliana, revealing that primed plants exhibit distinct gene expression and methylation patterns compared to non-primed plants. DNA methylation mutants, especially met1 lacking CG methylation, showed altered cold memory and misregulation of the CBF gene cluster, indicating that methylation ensures transcriptional precision during stress recall.
The complete chloroplast genome of the endemic fruit species Dillenia philippinensis was sequenced, assembled, and annotated, revealing a 161,591‑bp quadripartite structure with 113 unique genes. Comparative analyses identified simple sequence repeats, codon usage patterns, and phylogenetic placement close to D. suffroticosa, providing a genomic resource for future breeding and conservation efforts.
The authors compiled and standardized published data on Rubisco dark inhibition for 157 flowering plant species, categorizing them into four inhibition levels and analyzing phylogenetic trends. Their meta‑analysis reveals a complex, uneven distribution of inhibition across taxa, suggesting underlying chloroplast microenvironment drivers and providing a new resource for future photosynthesis improvement efforts.
Characterization of a dominant SmNac-like gene as a candidate for photosensitivity in the fruit peel of eggplant
Authors: Gomis-Cebolla, J., Manrique, S., Arrones, A., Toledo-Tolgar, M. D., Luna, J., Baraja-Fonseca, V., Sanchez-Pascual, J., Gimeno-Paez, E., Plazas, M., Gramazio, P., Vilanova, S., Prohens, J.
The study identified that fruit photosensitivity in eggplant is governed by a single dominant gene, with QTLs clustering at the distal end of chromosome 10 (84.1-87.9 Mb). Bulked segregant analysis sequencing and RNA‑seq highlighted the SmNAC1‑like transcription factor as a likely regulator of anthocyanin accumulation, though no coding sequence mutations were detected, suggesting regulatory control at another level.
Six new Viola species and two reinstated species from China were identified using field surveys, detailed morphological comparison, and phylogenetic analysis of ITS and GPI gene sequences, placing them in section Plagiostigma subsect. Diffusae. The GPI data offered higher resolution, indicating complex relationships possibly due to ancient hybridization or incomplete lineage sorting, thereby clarifying species boundaries and evolutionary patterns in Chinese Viola.
Novel substrate affinity of FaCCR1 and FaCCR1/FaOCT4 expression control the content of medium-chain esters in strawberry fruit
Authors: Roldan-Guerra, F. J., Amorim-Silva, V., Jimenez, J., Mari-Albert, A., Torreblanca, R., Ruiz del Rio, J., Botella, M. A., Granell, A., Sanchez-Sevilla, J. F., Castillejo, C., Amaya, I.
The study identified a major QTL on chromosome 6A that accounts for 40% of variation in medium-chain ester (MCE) levels in strawberry fruit, pinpointing FaCCR1 and FaOCT4 as the causal genes. Functional validation through subcellular localization, transient overexpression, enzymatic assays, and molecular docking demonstrated that FaCCR1 also catalyzes MCE precursor reactions, and a KASP marker in FaOCT4 was developed for breeding fragrant cultivars.