Search Results (98)

Background/Objectives: Sweet potato is a tropical and subtropical crop and its growth and yield are susceptible to low-temperature stress. However, the molecular mechanisms underlying the low temperature stress of sweetpotato are unknown. Methods: In this work, combined transcriptome and metabolism analysis was employed to investigate the low-temperature responses of two sweet potato cultivars, namely, the low-temperature-resistant cultivar “X33” and the low-temperature-sensitive cultivar “W7”. Results: The differentially expressed metabolites (DEMs) of X33 at different time stages clustered in five profiles, while they clustered in four profiles of W7 with significant differences. Differentially expressed genes (DEGs) in X33 and W7 at different time points clustered in five profiles. More DEGs exhibited continuous or persistent positive responses to low-temperature stress in X33 than in W7. There were 1918 continuously upregulated genes and 6410 persistent upregulated genes in X33, whereas 1781 and 5804 were found in W7, respectively. Core genes involved in Ca²⁺ signaling, MAPK cascades, the reactive oxygen species (ROS) signaling pathway, and transcription factor families (including bHLH, NAC, and WRKY) may play significant roles in response to low temperature in sweet potato. Thirty-one common differentially expressed metabolites (DEMs) were identified in the two cultivars in response to low temperature. The KEGG analysis of these common DEMs mainly belonged to isoquinoline alkaloid biosynthesis, phosphonate and phosphinate metabolism, flavonoid biosynthesis, cysteine and methionine metabolism, glycine, serine, and threonine metabolism, ABC transporters, and glycerophospholipid metabolism. Five DEMs with identified Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were selected for correlation analysis. KEGG enrichment analysis showed that the carbohydrate metabolism, phenylpropanoid metabolism, and glutathione metabolism pathways were significantly enriched and played vital roles in low-temperature resistance in sweet potato. Conclusions: These findings contribute to a deeper understanding of the molecular mechanisms underlying plant cold tolerance and offer targets for molecular breeding efforts to enhance low-temperature resistance. Full article

As an important characteristic and horticultural crop in China, sweetpotato can be used as food, industrial raw material, vegetable, and ornamental material. Purple sweetpotato for table use is rich in anthocyanin, which leads to some bitter taste, so it needs further quality improvement. Genetic engineering technology is an effective method to improve crop traits, but there are few reports on genes that can improve sweetpotato sweetness and taste. A xylosidase gene (Ibα-XYL1) was cloned from sweetpotato variety ‘Yanshu 25’ with a fragment size of 2796 bp and encoding 932 amino acid sequences. It has a typical transmembrane domain and three functional domains, which are localized at cell membrane. Reduction in Ibα-XYL1 gene expression had no significant effect on the expansion characteristics and anthocyanin content of sweetpotato storage root (SPSR), but it could up-regulate the expression of sucrose synthesis related genes (SuS, SuPS) and promote the accumulation of soluble sugar in fresh transgenic SPSR. At the same time, it could up-regulate the expression of genes related to starch synthesis modifications (GASS, SBE) and starch decomposition (AMY and BAM), reduce the starch granule size and the starch pasting temperature, promote the conversion of starch to maltose, increase the soluble sugar content, and improve the sweetness and taste of steamed transgenic SPSR. The results are of great significance for quality improvement of sweetpotato. Full article

Ammonium greatly influences nutrient partitioning and root architecture, particularly in the tuberous crops where assimilate translocation is critical for yield formation. However, relatively few studies have systematically delved into the physiological and molecular mechanisms of ammonium on assimilate translocation and root growth in sweetpotato (Ipomoea batatas Lam.). In this study, we investigated the morphological, physiological, and molecular effects of different concentrations of ammonium (0, 0.5, 1.0, 3.0, 5.0 mM) on the growth of the Sushu16 variety in the root-swelling stage. The plant weight and leaf area index of Sushu16 seedlings exhibited a progressive increase with elevated ammonium levels. However, the weight, volume, and number of storage roots (SRs) displayed a trend of a rapid rise and substantial decline, peaking at 1 mM ammonium. Similarly, the chlorophyll content, photosynthetic rate, and stomatal conductance were significantly increased with 1 mM ammonium treatment. Further, the contents of CK, ABA, and IAA increased first and then decreased, reaching a maximum at 1 mM ammonium. Notably, the “down then up” trend of sucrose content in leaves and stems contrasted with the fall–rise pattern of starch content in SRs at 1 mM ammonium. Furthermore, we screened 34 significant DEGs involved in photosynthesis, starch biosynthetic processes, and hormone signal pathway in SRs by RNA-Seq. All the results indicated that 1 mM ammonium had a promotive effect on source–sink conversion and SR production in Sushu16, which highlights potential targets for breeding or agronomic strategies to optimize yield formation in sweetpotato. Full article

Although sweet potato (Ipomoea batatas) is gaining importance in West Africa, it remains uncertain whether the research is adequately advanced to support the promotion of this crop in the region. Consequently, this systematic review of 125 articles provides a detailed overview of studies focused on sweet potatoes in West Africa. The paper explores various bibliometrics, the research geographic spread, and the topics discussed (e.g., food security and nutrition, climate resilience, livelihoods). The study indicates that sweet potato has the potential to address multiple issues in West Africa, including food and nutrition insecurity (especially micronutrient deficiencies, e.g., vitamin A) as well as poverty. However, it also reveals significant research gaps in terms of geographical and thematic areas. From a geographical perspective, research is primarily conducted in Nigeria and Ghana. From a thematic perspective, there are deficiencies in areas like economics and social sciences, applications in animal husbandry, marketing, use of leaves, irrigation methods, and impacts on climate resilience and livelihoods. There is a pressing need for collaborative research and knowledge exchange among nations to fully realize the potential of sweet potato and develop its value chains to contribute to sustainable socio-economic development across West Africa. Full article

Anaerobic soil disinfestation (ASD) is a promising alternative to synthetic chemical-driven pest management methods facilitated by incorporating carbon sources into the soil, tarping the soil with plastic mulch, and irrigating to soil saturation. To evaluate the impact of ASD on southern root-knot nematode [Meloidogyne incognita (Kofoid & White), SRKN] and yellow nutsedge (Cyperus esculentus L.) management in organically grown sweetpotato, greenhouse studies were conducted. The treatments were structured as a factorial of two carbon amendments [chicken manure + molasses (CM + M), and no additional carbon (control)] by 20 sweetpotato genotypes with 4 replications using a randomized complete block design. The results suggest that the microcosms receiving the carbon amendment spent the most time under anaerobic conditions (<200 mvh). Planting of sweetpotato genotypes in CM + M-treated microcosms resulted in 60–90% and 56–92% suppression of soil population and egg reproduction of SRKN as compared to no additional carbon. The application of CM + M reduced overall weed cover by 79% relative to the control. Sweetpotatoes in CM + M-treated microcosms had significantly higher dry above-ground biomass (6.8 g) as compared to the control (3.6 g). The results of this study demonstrated that ASD has the potential to manage nematodes and weeds in organic sweetpotato production systems. Full article

Sweetpotato is the seventh largest crop worldwide, and soil salinization is a major environmental stress limiting its yield. Recent studies have shown that noncoding RNAs (ncRNAs) play important regulatory roles in plant responses to abiotic stress. However, ncRNAs in sweetpotato remain largely unexplored. This study analyzed the characteristics of salt-responsive ncRNAs in sweetpotato adventitious roots under salt stress via whole-transcriptome RNA sequencing. The results revealed that 3175 messenger RNAs (mRNAs), 458 microRNAs (miRNAs), 544 long-chain ncRNAs (lncRNAs), and 23 circular RNAs (circRNAs) were differentially expressed. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that most differentially expressed mRNAs (DEmRNAs) and miRNAs (DEmiRNAs) were enriched primarily in phenylpropanoid biosynthesis, starch and sucrose metabolism, the Mitogen-Activated Protein Kinase (MAPK) signaling pathway, plant hormone signal transduction, the mRNA surveillance pathway, and ATP-binding cassette (ABC) transporters. Gene Ontology (GO) enrichment analysis revealed that the majority of DEmRNAs, their target DEmiRNAs, and differentially expressed lncRNAs (DElncRNAs) were associated with the cell wall, oxidation–reduction, the plasma membrane, protein phosphorylation, metabolic processes, transcription factor activity, and the regulation of transcription. Additionally, based on the competitive endogenous RNA (ceRNA) hypothesis, we predicted interactions among different RNAs and constructed a salt-responsive ceRNA network comprising 22 DEmiRNAs, 42 DEmRNAs, 27 DElncRNAs, and 10 differentially expressed circRNAs (DEcircRNAs). Some miRNAs, such as miR408, miR169, miR160, miR5139, miR5368, and miR6179, were central to the network, suggesting their crucial roles in the sweetpotato salt response. Our findings provide a foundation for further research into the potential functions of ncRNAs and offer new targets for salt stress resistance improvement through the manipulation of ncRNAs. Full article

Addressing malnutrition and vitamin A deficiency in Ethiopia necessitates innovative, food-based solutions such as biofortified crops. This study assesses the adoption rates of Orange-Fleshed Sweetpotato (OFSP) and examines the factors influencing adoption among project participants, non-participants, and counterfactual households in the former Southern Nations, Nationalities, and Peoples’ (SNNPs) region. Primary data were collected in 2023 through a survey of 990 households across six districts, and logistic regression was employed to identify key determinants of adoption. The findings reveal OFSP adoption rates of 53% among participants, 56% among non-participants, and 42% among counterfactual households, with significant variation across regions. Factors positively influencing adoption include household education, proximity to health centers and OFSP multiplication sites, frequent extension contact, and access to agricultural services. This study underscores the potential of newly released OFSP varieties to enhance food security and resilience in malnutrition-prone areas. The comparable adoption rates between participants and non-participants highlight significant spillover effects from long-term interventions, suggesting widespread community benefits. However, the limited adoption of complementary OFSP package components points to the need for enhanced training programs and streamlined technology dissemination strategies. These findings contribute to understanding how biofortified crops can be scaled effectively to improve food security and nutrition, offering valuable insights for policy and program design. Full article

In Bangladesh, sweetpotato is the fourth most important source of carbohydrates behind rice, wheat, and potatoes. Potassium is vital for sweetpotato growth, boosting tuber size, sweetness, disease resistance, and yield quality, with deficiencies leading to poor tuber formation and increased stress susceptibility. The present study evaluated the effect of varying dosages of potassium fertilizer (Muriate of Potash, MoP) on the growth, yield, and biochemical qualities of sweetpotato. As a genetic material, BAU sweetpotato-5 was chosen as it is recognized for its high yield, short duration, and nutritional advantages. There were three treatments—full dosage of MoP (321.6 kg ha⁻¹, T₀), half dosage of MoP (160.8 kg ha⁻¹, T₁) and no MoP (T₂). Four replications of a randomized complete block design (RCBD) were used in the experiment. According to analysis of variance, the morphological and biochemical parameters, such as the fresh weight plant⁻¹, number of tuber plant⁻¹, chlorophyll content, total phenolic content, vitamin C, carotenoid, anthocyanin, Zn, and Fe content varied significantly among treatments. The application of the full recommended dosage of MoP resulted in the highest values for several traits, including the fresh weight plant⁻¹, number of tuber plant⁻¹, chlorophyll content, carotenoid, anthocyanin, and Fe content. Conversely, total phenolic content and vitamin C were highest without MoP application. Principal component analysis (PCA) differentiated treatment T₀ from T₁ and T₂ due to higher positive coefficients of the number of leaves at 115 days after transplantation, vine length at 115 days after transplantation, number of branches, stem diameter, fresh weight plant⁻¹, tuber length, tuber diameter, tuber weight, number of tuber plant⁻¹, SPAD, carotenoid, anthocyanin, Fe, and negative coefficients of total phenolic content, vitamin C, and Zn. The findings suggest that potassium is integral to maximizing both yield and key nutritional components in sweetpotato cultivation. Full article

Background/Objectives: Sweetpotato black rot, caused by Ceratocystis fimbriata, is a severe fungal disease in sweetpotato production. Biological control strategies represent a promising, environmentally sustainable approach to managing this disease. This study investigates the biocontrol potential of Bacillus amyloliquefaciens SFB-1 against C. fimbriata. Methods: The antagonistic activities of strain SFB-1 on C. fimbriata were assessed through in vitro assays, including evaluations of mycelial inhibition, spore germination, and mycelial morphology. Pathogenicity assays on harvested sweetpotato roots assessed lesion diameter and depth. A transcriptomic analysis of C. fimbriata exposed to strain SFB-1 was performed to explore the underlying antifungal mechanism of SFB-1 on C. fimbriata. The qRT-PCR was employed to validate the RNA-seq results. Results: In vitro assays demonstrated that strain SFB-1 inhibited C. fimbriata mycelial growth by up to 81.01%, caused mycelial swelling, and completely suppressed spore germination at 10⁸ CFU/mL. The cell-free supernatant of strain SFB-1 also suppressed C. fimbriata growth. Pathogenicity assays revealed that strain SFB-1 treatments reduced lesion diameter and depth on harvested sweetpotato roots by over 50% compared to untreated controls. Transcriptomic analysis of C. fimbriata treated with strain SFB-1 identified 1164 differentially expressed genes, with significant alterations in genes associated with cell wall integrity, cell membrane stability, spore germination, detoxification, and antioxidant responses. The qRT-PCR validation of 16 genes confirmed the consistency with the RNA-seq results. Conclusions: B. amyloliquefaciens SFB-1 demonstrates significant biocontrol efficacy against C. fimbriata through multiple mechanisms, positioning it as a promising solution for the sustainable management of sweetpotato black rot. Full article

Purple-fleshed sweetpotatoes (PFSPs) are rich in anthocyanins and are one of the health foods of interest. In this study, the effects of steaming on the anthocyanin, starch, soluble sugar, volatile organic compounds (VOCs) and pasting properties of nine PFSPs from China were investigated. The anthocyanin content of raw PFSP ranged from 9 to 185 mg/100 g. The total starch content decreased and soluble sugar content increased in all purple potatoes after steaming. Among the nine PFSPs varieties, Guangshu20 showed the greatest decrease in starch content (30.61%) and the greatest increase in soluble sugar content (31.12%). The pasting properties affected the taste of the PFSPs, with Shuangpihuang having the lowest peak viscosity (720.33 cP) and Guangzishu12 having the highest peak viscosity (2501.67 cP). Correlation studies showed that the anthocyanin content and pasting properties were negatively correlated with most of the sensory indicators, whereas the soluble sugar content of steamed PFSPs was significantly positively correlated with sweetness. A total of 54 VOCs were identified in this study, and aldehydes and terpenoids were the major VOCs in PFSPs. This study provides a theoretical basis for the processing of different PFSP varieties. Full article

Sweetpotato (Ipomoea batatas L.) is an essential food crop globally, especially for farmers facing resource limitations. Like other crops, sweetpotato cultivation faces significant production challenges due to viral infections. This study aimed to identify and characterize viruses affecting sweetpotato crops in Uganda, mostly those associated with sweetpotato virus disease (SPVD). Infected leaf samples were collected from farmers’ fields in multiple districts spanning three regions in Uganda. MiSeq, a next-generation sequencing platform, was used to generate reads from the viral nucleic acid. The results revealed nine viruses infecting sweetpotato crops in Uganda, with most plants infected by multiple viral species. Sweet potato pakakuy and sweet potato symptomless virus_1 are reported in Uganda for the first time. Phylogenetic analyses demonstrated that some viruses have evolved to form new phylogroups, likely due to high mutations and recombination, particularly in the coat protein, P1 protein, cylindrical inclusion, and helper component proteinase regions of the potyvirus. The sweet potato virus C carried more codons under positive diversifying selection than the closely related sweet potato feathery mottle virus, particularly in the P1 gene. This study provides valuable insights into the viral species infecting sweetpotato crops, infection severity, and the evolution of sweet potato viruses in Uganda. Full article

Automated sorting of sweetpotatoes is necessary to reduce labor dependence and costs that are significant at today’s sweetpotato packing sheds. Although optical sorters have been widely adopted in commercial packing lines for many horticultural commodities, there remains an unmet need to develop dedicated technology for the automated grading and sorting of sweetpotatoes. Sorting mechanisms are the critical component that physically segregates products according to quality grades determined by a machine vision or imaging system. This study presents the new engineering prototypes and evaluation of three different pneumatically powered mechanisms for sorting sweetpotatoes online. Among the three sorters, the sorting mechanism, which employs a linear air cylinder to drive a paddle directly striking products, achieved the best overall accuracy and repeatability of 98% and 96.8%, respectively, at conveyor speeds of 4–12 cm/s. The sorter based on a rotary actuator also delivered decent accuracy and repeatability of 97.9% and 95.6%, respectively. The best-performing sorting mechanism was integrated with a machine vision system that graded sweetpotatoes based on size and surface defect conditions to separate graded sweetpotatoes into three quality categories. The errors of 0–1% due to the sorting process were obtained at conveyor speeds of 4–12 cm/s, confirming the efficacy of the manufactured sorting mechanisms. There was a declining trend with the conveyor speed in the performance of the sorting mechanisms when evaluated either in a standalone or integrated configuration. The proposed sorting mechanisms that are simple in construction and operation and of low cost are useful for developing a more full-fledged sorting system. More research is needed to enhance sorting performance and conduct extensive tests at higher conveyor speeds for practical application. Full article

Weeds and nematodes are particularly problematic in organic sweetpotato production due to a lack of effective pesticides. Anaerobic soil disinfestation (ASD) has the potential to fit into current pest management practices as an alternative to pesticide application. Greenhouse studies were conducted at the Clemson Coastal Research and Education Center (CREC) in Charleston, SC, to investigate the impact of carbon source amendment and a no carbon source treatment, and soil type on cumulative anaerobicity, weed control, nematode population, and sweetpotato vigor. Microcosms were filled with one of three different soil types (Charleston—loamy/native; Blackville—high coarse sand content; and Clemson—high clay content) and were mixed with cottonseed meal (CSM) or no carbon amendment. The pots were then sealed with plastic totally impenetrable film (Tif) for 6 weeks, followed by the transplanting of sweetpotato (cv Bayou Belle) slips. The results suggested that the CSM-treated microcosms spent more time under anaerobic conditions than those treated with the no carbon amendment. The microcosms that experienced a longer duration of anaerobicity had a lower percent weed cover (49%), fewer nematode egg masses, and a lower gall index when compared to microcosms which experienced a shorter duration of anaerobicity. Significantly higher instances of leaf necrosis were observed in the sweetpotato slips sown in the CSM-treated microcosms. The addition of CSM as a carbon source to facilitate ASD resulted in similar above-ground biomasses of the sweetpotato plants compared to the treatments containing no carbon amendment. However, a significantly lower below-ground biomass of the sweetpotato plants was observed in the CSM-treated microcosms. Full article

Small public breeding programs focused on specialty crops have many barriers to adopting technology, particularly creating and using genetic marker panels for genomic-based decisions in selection. Here, we report the creation of a DArTag panel of 3120 loci distributed across the sweetpotato (Ipomoea batatas [L.] Lam) genome for molecular-marker-assisted breeding and genomic prediction. The creation of this marker panel has the potential to bring cost-effective and rapid genotyping capabilities to sweetpotato breeding programs worldwide. The open access provided by this platform will allow the genetic datasets generated on the marker panel to be compared and joined across projects, institutions, and countries. This genotyping resource has the power to make routine genotyping a reality for any breeder of sweetpotato. Full article

Soil acidification is a significant form of agricultural soil degradation, which is accelerated by irrational fertilizer application. Sweetpotato and wheat rotation has emerged as an important rotation system and an effective strategy to optimize nutrient cycling and enhance soil fertility in hilly areas, which is also a good option to improve soil acidification and raise soil quality. Studying the effects of different fertilization regimes on soil acidification provides crucial data for managing it effectively. An eight-year field experiment explored seven fertilizer treatments: without fertilization (CK), phosphorus (P) and potassium (K) fertilization (PK), nitrogen (N) and K fertilization (NK), NP fertilization (NP), NP with K chloride fertilization (NPK1), NP with K sulfate fertilization (NPK2), and NPK combined with organic fertilization (NPKM). This study focused on the soil acidity, buffering capacity, and related indicators. After eight years of continuous fertilization in the sweetpotato–wheat rotation, all the treatments accelerated the soil acidification. Notably, N fertilization reduced the soil pH by 1.30–1.84, whereas N-deficient soil showed minimal change. Organic fertilizer addition resulted in the slowest pH reduction among the N treatments. Both N-deficient (PK) and organic fertilizer addition (NPKM) significantly increased the soil cation exchange capacity (CEC) by 8.83% and 6.55%, respectively, compared to CK. Similar trends were observed for the soil-buffering capacity (pHBC). NPK2 increased the soil K⁺ content more effectively than NPK1. NPKM reduced the sodium and magnesium content compared to CK, with the highest magnesium content among the treatments at 1.60 cmol·kg⁻¹. Regression tree analysis identified the N input and soil magnesium and calcium content as the primary factors influencing the pHBC changes. Structural equation modeling showed that the soil pH is mainly influenced by the soil ammonium N content and pHBC, with coefficients of −0.28 and 0.29, respectively. Changes in the soil pH in the sweetpotato–wheat rotation were primarily associated with the pHBC and N input, where the CEC content emerged as the main factor, modulated by magnesium and calcium. Long-term organic fertilization enhances the soil pHBC and CEC, slowing the magnesium reduction and mitigating soil acidification in agricultural settings. Full article