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Social Impact Statement: Cassava is a vital food source for millions worldwide, crucial for food security and economic stability. This study analyzed cell wall polysaccharides in cassava roots to understand their impact on cooking properties. We found these polysaccharides influence the textural attributes of cassava roots, essential for both cooking and consumption. The research highlights the need to further identify and analyze cassava cell wall components. By improving our understanding of these components, we can improve food security, affordability, and resilience in diverse regions, ultimately contributing to global food security and better aligning with consumer preferences. Summary: The textural attributes of cassava roots significantly influence preferences in cooking and consumption as a food source, yet the specific components dictating these properties remain unclear. We aimed to identify the factors shaping the cooking properties of cassava roots.We conducted a compositional analysis of 22 traits in a diverse F1 biparental population derived from soft‐ and hard‐boiling progenitors. The traits encompassed cooking qualities, starch properties, and cell wall composition.Specific cell wall components including cellulose, xylan, un‐esterified, and methyl‐esterified homogalacturonan (HG) demonstrated a correlation with cooking quality attributes: sensory assessments related to texture (SAT) and water absorption during boiling (WAB). Correlation and regression analyses revealed that these wall components collectively contribute to 20% of SAT variability and 14% of WAB variability. SAT appeared to be influenced by methyl‐esterified and un‐esterified HGs, xylan, and cellulose, impacting the tensile strength of the cell wall. Conversely, WAB appeared to be associated with methyl‐esterified HG, potentially altering water absorption properties. Although genome‐wide association studies (GWAS) were unable to identify significant SNPs for SAT and WAB, notable associations emerged for cellulose, xylan, and un‐esterified‐ and methyl‐esterified HG. Candidate genes associated with these SNPs point towards diverse cell wall‐related proteins, transcription factors, sugar metabolism‐related genes, and glycosyl hydrolases.This study provides insights into the relationship between cassava root compositions and cooking characteristics and the role of wall components in determining the cooking quality of edible cassava. This information represents a substantial contribution towards the development of protocols for selecting varieties with texture preferences. [ABSTRACT FROM AUTHOR]

Cassava (Manihot esculenta Crantz) was introduced to Southeast Asia in the 16th–17th centuries and has since flourished as an industrial crop. Since the 1980s, Thailand has emerged as the leading producer and exporter of cassava products. This growth coincided with the initiation of cassava breeding programs in collaboration with the International Center for Tropical Agriculture (CIAT), focusing on root yield and starch production. The success of Thai cassava breeding programs can be attributed to the incorporation of valuable genetic diversity from international germplasm resources to cross with the local landraces, which has become the genetic foundation of many Thai commercial varieties. Effective evaluation under diverse environmental conditions has led to the release of varieties with high yield stability. A notable success is the development of Kasetsart 50. However, extreme climate change poses significant challenges, including abiotic and biotic stresses that threaten cassava root yield and starch content, leading to a potential decline in starch-based industries. Future directions for cassava breeding must include hybrid development, marker-assisted recurrent breeding, and gene editing, along with high-throughput phenotyping and flower induction. These strategies are essential to achieve breeding objectives focused on drought tolerance and disease resistance, especially for CMD and CBSD. [ABSTRACT FROM AUTHOR]

Grafting of cassava (Manihot esculenta Crantz) understocks with scions from Manihot glaziovii was proposed to improve the cassava root yield and as a temporal approach to overcoming the problem of cassava mosaic disease (CMD). This work compared performance of nongrafted KU50 with M. esculenta grafted as understock with M. glaziovii, KU50 or HB80 scions. KU50 and HB80 are released M. esculenta varieties. Work was conducted in the field using a randomized complete block design (RCBD) with four replicates in two seasons (rainy and dry seasons) in Thailand. The M. glaziovii grafted plants were larger than nongrafted controls. Grafting also increased fresh root yield by 25% (dry season) and 37% (rainy season) and dry matter content by 19% (dry season) and 42% (rainy season) over the nongrafted controls. Net photosynthesis (Pn), stomatal conductance (gs) and growth parameters indicated that the grafted plants had a higher photosynthetic capacity and more vigorous growth than nongrafted controls during the dry season. Correlation coefficients of Pn and gs with growth and productivity parameters at different ages of the plant were highly significant during the dry season but not in the rainy season. This study demonstrated that M. glaziovii–cassava grafting improved cassava growth and root yield. [ABSTRACT FROM AUTHOR]

Key message: GWAS identified eight yield-related, peak starch type of waxy and wild-type starch and 21 starch pasting property-related traits (QTLs). Prediction ability of eight GS models resulted in low to high predictability, depending on trait, heritability, and genetic architecture. Cassava is both a food and an industrial crop in Africa, South America, and Asia, but knowledge of the genes that control yield and starch pasting properties remains limited. We carried out a genome-wide association study to clarify the molecular mechanisms underlying these traits and to explore marker-based breeding approaches. We estimated the predictive ability of genomic selection (GS) using parametric, semi-parametric, and nonparametric GS models with a panel of 276 cassava genotypes from Thai Tapioca Development Institute, International Center for Tropical Agriculture, International Institute of Tropical Agriculture, and other breeding programs. The cassava panel was genotyped via genotyping-by-sequencing, and 89,934 single-nucleotide polymorphism (SNP) markers were identified. A total of 31 SNPs associated with yield, starch type, and starch properties traits were detected by the fixed and random model circulating probability unification (FarmCPU), Bayesian-information and linkage-disequilibrium iteratively nested keyway and compressed mixed linear model, respectively. GS models were developed, and forward predictabilities using all the prediction methods resulted in values of − 0.001–0.71 for the four yield-related traits and 0.33–0.82 for the seven starch pasting property traits. This study provides additional insight into the genetic architecture of these important traits for the development of markers that could be used in cassava breeding programs. [ABSTRACT FROM AUTHOR]

Cassava is susceptible to waterlogged soil. In order to find the right variety for breeding purposes, a research needs to find proper screening parameters. They must be easy, fast, and economical practice. Therefore, in this research, upper-ground morphological responses of cassava to water deficit conditions in tissue were evaluated as traits to screen cassava breeding lines for water-logging tolerance. Hanatee variety is a landrace grown in the well-watered field for cooking purpose and was bred with Kasetsart 50 which is a high yielding commercial variety. These two varieties together with five breeding lines have water-logging tolerance potential in the field. They were evaluated in the pot for waterlogging stress at two vegetative growth stages at 105 DAP and 165 DAP for 12 days in each stress period. Among these seven varieties/lines, there were no varieties/lines showing waterlogging tolerance under this condition over others, but all showing recovery response. The results indicated that cassava at the vegetative growth stage had a recovery mechanism for the upper-ground parts, but not for the storage root tissue after waterlogging stress for 12 days. There was a potential of using the ratio of leaf retention to screen cassava germplasm or breeding lines for waterlogging tolerance. [ABSTRACT FROM AUTHOR]