Genetius

The study demonstrates that CRISPR‑mediated knockout of cassava eIF4E family members, particularly the nCBP-1 and nCBP-2 genes, significantly reduces Cassava brown streak disease (CBSD) symptoms and viral load, though redundancy remains. Double mutants in the nCBP clade showed the strongest phenotype, and a yeast two‑hybrid screen identified the L51F substitution in nCBP-2 as a key loss‑of‑affinity mutation, suggesting that analogous edits across the eIF4E family could enhance resistance without pleiotropic effects.

The study applied four linear mixed‑model frameworks to dissect fresh root yield variation among 42 provitamin A cassava genotypes across two contrasting rainfall seasons, identifying months after planting as the primary source of variance. While genotypic effects were modest, specific accessions showed broad adaptability or drought responsiveness, highlighting the value of incorporating environmental sensitivity into cassava breeding.

The study sequenced 387 Colombian cassava landraces and combined them with >1000 existing genotypes to assess genomic diversity and loss‑of‑function (LoF) variation. Landraces retained high diversity and specific LoF alleles linked to coumarin biosynthesis and immunity, while climate‑associated loci were identified as candidates for targeted gene editing to improve adaptation. These findings highlight landraces as a valuable reservoir for breeding and functional genomics in cassava.

Transgenic cassava plants expressing the Arabidopsis thaliana potassium channel variant AKT2var in vascular tissue showed enhanced electron transport, CO₂ assimilation, and bulk flow, leading to greater source‑sink carbohydrate transport as evidenced by ¹¹C‑PET imaging and metabolite profiling. These physiological improvements translated into significantly higher storage‑root yields in both greenhouse and multi‑year field trials, and the plants also displayed increased drought tolerance, highlighting targeted K⁺ transport as a viable strategy for boosting cassava productivity under limited fertilizer and adverse climate conditions.

A time-course RNA-Seq experiment compared gene expression in a susceptible cassava cultivar (TMS 96/0304) and two resistant lines (DSC 167 and DSC 260) following Cassava brown streak virus inoculation. Resistant genotypes showed early, tissue‑specific transcriptional responses, especially in stems at 1 day post‑inoculation, whereas the susceptible line exhibited a later surge of differentially expressed genes at 10 days. The data suggest that early regulation of hormone, defense, and signaling pathways underlies resistance, though many implicated genes remain functionally uncharacterized.

The study employed a dCas9‑DMRcd‑SunTag system to induce targeted DNA methylation at the promoters of two cassava eIF4E-family genes (nCBP-1 and nCBP-2) that act as susceptibility factors for cassava brown streak disease (CBSD). Unlike previous work on the MeSWEET10a promoter, the authors found that CRISPR interference alone reduced gene expression, and they propose future genetic crosses to separate the epigenetic reagents and test the heritability of the methylation-mediated resistance.

Bi-parental crosses between a whitefly‑tolerant cassava variety (ECU72) and a susceptible line (COL2246) were used to generate F1 and F2 populations, which were screened for enhanced whitefly resistance. Untargeted LC‑MS metabolomics coupled with PCA identified distinct metabolite profiles and quantitative markers (e.g., feature 316.0924) linked to resistance, highlighting perturbed pathways such as cyanogenic glycosides, apocarotenoids, and phenylpropanoids. These markers provide low‑cost proxies for breeding whitefly‑tolerant cassava varieties.

Using a cryo-sectioning strategy, the study generated high‑resolution transcriptome maps of the vascular cambium in cassava stems and storage roots, revealing that storage parenchyma formation is linked to repression of secondary cell‑wall genes and GA signaling, alongside active auxin, ABA, and MeKNOX1 pathways. These findings identify key transcriptional regulators differentiating storage root parenchyma from stem xylem.