Biology subjects

Benejam, J.

Publications and source records attributed to Benejam, J..

3 recordsLinked to original sources

bioRxiv2026

Reduced confidence intervals and novel candidate genes for quantitative trait loci associated with apple scab resistance in Malus domestica

Apple scab, caused by Venturia inaequalis, remains one of the most damaging diseases in apple orchards, driving intensive pesticide use worldwide. Reducing this dependence requires the deployment of durable resistance, ideally through the combination of major resistance genes (R genes) with quantitative trait loci (QTL) that confer partial and potentially complementary protection. Yet, few apple scab QTLs have been functionally validated, and their underlying mechanisms remain largely unresolved. Here, we refined and functionally described, with transcriptomic data, five resistance QTLs in a biparental population of 1,970 individuals derived from the cross TN 10-8 x Fiesta. Using 43 newly developed KASP markers, QTL locations were substantially precised through high-resolution genotyping and phenotyping with two V. inaequalis isolates exhibiting contrasting virulence. Four QTL (qT1, qF11, qF17, qT13) were validated, while qF3 was not confirmed. Transcriptomic data comparison revealed the expression of candidate genes within the narrowed intervals, including receptor-like proteins in qT1, and RNAi- and signaling-related genes in qF11 and qF17, suggesting a diversified and complementary defense network. These findings refine the genetic architecture of apple scab resistance and suppose the existence of shared molecular pathways between major R gene, such as the well-described Rvi6 gene, and quantitative resistance, with for instance the QTL qT1. The identified loci and markers provide robust tools for marker-assisted and genomic breeding aimed at developing apple cultivars with complementary and potentially durable resistance pathways.

plant biology↗

bioRxiv2025

Mammalian growth-regulating factors enhance regeneration of recalcitrant transgenic tomato accessions

Genome editing is now available for many crops. It has increased our ability to study gene function and has changed the field of plant transgenesis. Nevertheless, the ability to regenerate plants from cell culture remains a limiting factor for many crops, and even for species with a good regeneration potential, some accessions remain recalcitrant. The physiological state of plant cells is involved in the process of plant growth and development and is closely linked to the network involving MAP-kinase signaling pathway. Some of the defense genes activated during the cellular repair process of transgenesis show high homologies with mammalian defense genes. We thus compared the percentage of transgenic plants obtained by CRISPR-Cas9 mutation in four genes involved in sugar and acid metabolism after supplementation with different mammalian growth factors and cytokines in six tomato accessions presenting a range of regeneration levels. We demonstrated, through three years of transgenesis experiments, that the use of mammalian growth factors during transgenesis improved regeneration rate of recalcitrant tomato accessions. We demonstrated that using cytokines not only improved transformation of difficult-to-transform accessions but also the production rate of stable secondary lines. Summary statementSupplementation of transformation medium with mammalian growth-regulating factors enhanced regeneration of tomato recalcitrant genotypes

plant biology↗

bioRxiv2019

Natural epiallelic variation is associated with quantitative resistance to the pathogen Plasmodiophora brassicae

Clubroot caused by the protist Plasmodiophora brassicae is a major disease affecting cultivated Brassicaceae. Here, we uncover the existence of a natural epigenetic variation that is associated with partial resistance to clubroot in Arabidopsis, by using QTL fine mapping followed by extensive DNA sequence and methylation analyses. We show that at QTL Pb-At5.2, DNA methylation variation is extensive across accessions and strictly correlates with expression variation of the two neighboring genes At5g47260 and At5g47280, which encode NLR-immune receptors. Moreover, these natural variants are stably inherited and are not consistently associated with any nucleotide variation. These findings suggest a direct role for epigenetic variation in quantitative resistance of plants to pathogen attacks.

genetics↗