Search Results (670)

Excessive fertilizer use poses environmental risks in the long term. Thus, plant growth-promoting rhizobacteria (PGPR) have been proposed as a complementary approach to reduce fertilizer use and prevent nutrient stress. Moreover, PGPR’s efficacy in sandy soil for sweet potato production in Northeast Thailand has not yet been reported. This study tested the hypothesis that PGPR inoculation could reduce fertilizer dependency while maintaining yield in nutrient-poor sandy soils. In this research, a field study was conducted from 2023 to 2024 in Chonnabot District, Khon Kaen, Thailand, to evaluate the effects of Azospirillum brasilense, Azotobacter vinelandii, Beijerinckia mobilis, and inorganic fertilizer on the Okinawan Orange and Carrot native sweet potato varieties. Treatments followed a factorial randomized complete block design with two factors, PGPR inoculation and fertilizer level (0%, 25%, 50%, 75%, and 100%), and were replicated three times. The results showed that PGPR dipping had no statistically detectable effect on sweet potato growth and yield (p > 0.05). However, a notable finding was that PGPR significantly increased the protein and fiber content of tubers (p < 0.01) while reducing carbohydrate content, which may have implications for the taste and the nutritional quality of sweet potatoes. In addition, the application of inorganic fertilizer had a significant effect on yield. The Carrot native variety achieved the highest yield (13,481.00 kg ha⁻¹) with 75% fertilizer, while the Okinawan Orange variety attained the highest yield (8866.00 kg ha⁻¹) with 100% fertilizer. These data could be used to assist farmers in determining their fertilizer usage. Full article

Foot rot, a disease caused by the fungal plant pathogen Diaporthe destruens, has been a major problem throughout East Asia. In major sweet-potato-producing regions, developing sweet potato cultivars that are resistant to foot rot has become an urgent priority. The possibility of selecting resistant cultivars by using polyphenols in the stems as markers was recently suggested, but this selection method has not been tested in the crossbreeding of sweet potato cultivars. In this study, we crossed the sweet potato cultivars ‘Konaishin’ and ‘Tamaakane’ (each of which is resistant to foot rot), analyzed the polyphenols in the stems of the resulting hybrid lines, and evaluated the possibility of selecting resistant lines. As a result, KT No. 7 and KT No. 8 showed similar or lower total polyphenol contents (145.9 and 112.9 mg GAE 100 g⁻¹ FW, respectively) compared to ‘Tamaakane’ (142.2 mg GAE 100 g⁻¹ FW). The selected line, KT No. 7, exhibited the highest resistance among the hybrids when it was directly inoculated with the foot rot pathogen using stems as test material, showing a disease severity value of 1.8, which was substantially lower than that of ‘Tamaakane’ (50.0). These results suggest that stem polyphenol content has potential as a marker for identifying promising candidates with foot rot resistance, although its predictive value may vary depending on genetic and environmental factors. This approach may help improve the efficiency of foot rot resistance screening in sweet potato breeding programs. Full article

Sweet potato (Ipomoea batatas (L.) Lam.) is increasingly recognized as a functional crop due to its rich content of health-promoting phytochemicals. This study compared the phenolic compound profiles of four sweet potato varieties differing in flesh colour (purple, orange, white, and pale yellow) cultivated in three distinct regions of Hungary. The objective was to evaluate the relative effects of pigmentation and growing location on antioxidant capacity. Tubers were collected in triplicate and analyzed spectrophotometrically (UV–Vis) for vitamin C, total flavonoids, and total polyphenols. Statistical analysis using two-way ANOVA and Tukey’s HSD revealed that flesh colour had a significant effect on all antioxidant parameters (p < 0.05), whereas geographic origin did not. Purple-fleshed tubers exhibited markedly higher levels of vitamin C (21.6 mg/100 mL), flavonoids (378.7 mg/100 mL), and polyphenols (37.0 mg/100 mL) compared with the other colour groups. These findings indicate that pigmentation is a stronger determinant of antioxidant potential than cultivation region. The results highlight the promising nutritional value of Hungarian purple-fleshed sweet potato varieties, supporting their use in functional food development and sustainable agricultural diversification strategies. Full article

The mechanized transplanting of sweet potato slips onto mulched raised beds in China’s Huang-Huai-Hai region faces significant challenges due to fragmented smallholder farms and the specific agronomic requirement of “boat-shaped” horizontal planting. To address this gap, this study aimed to develop a compact, cost-effective transplanter that meets the “boat-shaped” planting agronomy and adapts to small plots. We designed the 2CGX-1 mini wheel-driven transplanter coupled with a tractor. This machine features a compact chassis (<1.5 m length) for enhanced maneuverability on small plots, a novel five-bar taking-planting mechanism optimized for boat-shaped placement (achieving a stem-soil angle of 56.2° and planting depth of 110 mm), and an integrated spring buffer system. Transmission design ensures precise synchronization between the dual-chain seedling feeding mechanism and planting actions, allowing plant spacing adjustment from 18 to 30 cm. Coupled Adams–EDEM simulations demonstrated that the buffer system reduces maximum resistance on the clip fingers by 37.8% when encountering obstacles. Field validation under optimal parameters (0.55 km/h operating speed, 30 plants/min transplanting frequency) showed high consistency: average planting depth 101.3 mm (SD 1.38), plant spacing 330.3 mm (SD 11.24), seedling length under the film 185 mm (SD 3.65), and stem-soil angle 47.9° (SD 3.41), with qualification rates exceeding 91.9% for all key parameters except submerged length (82.5%). Compared with manual planting (≤0.1 ha/day per person, labor cost > ¥800/ha), this transplanter achieves a daily operational efficiency of ~0.35 ha/day (calculated by 0.55 km/h speed × 0.8 m working width × 8 h daily working time). Meanwhile, the consistency of its key planting indicators and the planting qualification rate are significantly superior to those of manual planting, while improving operational quality and significantly reducing labor cost input. Deviations in individual indicators mainly stem from planting positioning deviations induced by terrain undulations in hilly test areas, and sweet potato seedlings’ tendency to fall off during clamping due to mechanical vibration. However, these errors are within the acceptable agricultural operation range and do not compromise the machine’s overall compliance with agronomic requirements. The transplanter effectively meets agronomic requirements while offering a cost-effective, adapted solution for small-scale sweet potato production systems, significantly advancing mechanization capabilities for mulched cultivation. Full article

Sweet potato is a nutrient-dense crop with the potential to improve food security, yet its productivity is constrained by drought stress. Metabolic profiling in sweet potato, particularly in response to abiotic stress, remains poorly understood, with limited knowledge on the metabolites contributing to drought response. The study aimed to profile and compare metabolites in drought-tolerant (cv Atacama) and drought-susceptible (cv Blesbok) sweet potato cultivars under water-deficient conditions. The cultivars were grown in a rainout shelter during the 2024 growing season at the Agricultural Research Council-Vegetable and Industrial Medicinal Plant (ARC-VIMP). The trial was laid out in a randomized block design with a plot size of 242 m squared with three drought treatment conditions, i.e., 30%, 50%, and 70% field capacity (FC). After two weeks of drought stress imposition, leaf samples were collected and analyzed for metabolite changes using untargeted ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Using chemometrics analysis, mainly using principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA), significant separation was shown between the three drought stress conditions and the two cultivars, highlighting variable metabolic accumulation. Ten significantly regulated metabolites were identified (VIP > 1, p < 0.05), with the most pronounced log₂ fold changes observed for kaempferol-3-O-galactoside (3.48), chlorogenic acid (3.34), glc-glc-octadecatrienoyl-sn-glycerol (3.14), and apigenin-7-O-β-D-neohesperidoside (2.71). Metabolite concentration varied in the two cultivars, although most were positively correlated with Atacama. Enriched pathways included flavonoid biosynthesis, zeatin biosynthesis, and starch and sucrose metabolism. These findings highlight cultivar-specific metabolic responses and propose candidate biomarkers for breeding drought-tolerant sweet potato. Full article

Sweet potato, Ipomoea batatas (L.) Lam., is a major food crop in developing countries and is considered essential for the food security of low-income populations. Among the factors limiting its production is the pest Bedellia somnulentella (Zeller) (Lepidoptera: Bedelliidae), recently recorded in Brazil, and for which no chemical control methods are available. Therefore, understanding the physiological changes caused by this pest attack is important to support management strategies. The objective was to evaluate chlorophyll a fluorescence parameters in eleven sweet potato genotypes subjected or not to B. somnulentella attack. A completely randomized design (CRD) was used, consisting of eleven treatments and twenty replicates. Initial fluorescence (F₀), maximum fluorescence (Fm), maximum/minimum fluorescence (Fm/F₀), variable fluorescence/maximum fluorescence ratio (Fv/Fm), and electron transport rate (ETR) were analyzed. In most of the genotypes evaluated, a reduction in F₀ was observed under attack by B. somnulentella, indicating photosynthetic stress, except in genotypes UFVJM 08, 18 and 291. Non-injured plants presented Fv/Fm values between 0.51 and 0.75, while attacked genotypes exhibited reduced values (0.35 to 0.53). ETR was also lower in damaged plants, evidencing photosynthetic stress. The results demonstrated a negative correlation between Fm/F_0, Fv/Fm and F₀. UFVJM 08, UFVJM 18, UFVJM 291, Brazlândia branca and Rubissol genotypes exhibited greater stability, maintaining more balanced fluorescence responses under pest pressure. Physiological differences between genotypes may reflect agronomic responses in the field. Full article

Drone insecticide spraying is generating increasing concern and interest among academics and the public. However, the differences in the quantity of insecticide delivered by this method, and its efficacy in pest control for individual plants, remain to be evaluated. We examined the distribution and quantity of an insecticide sprayed on sweet potato plants and the method’s efficacy in controlling a subterranean weevil infestation. To evaluate delivery patterns, water-sensitive paper was placed on the canopy of the plants, and the insecticide was sprayed from a drone at the registered concentration. Although there was minimal deflection of flight paths (under crosswinds ≤ 3.0 m/s), the distribution varied across the field. The quantity administered was within the regulated range for the insecticide. Efficacy was not significantly influenced by either the quantity administered or pattern of spraying, and the drone application resulted in an equivalent level of control as a conventional ground-based application. While the quantity of the insecticide applied to the canopy was uneven, the method’s efficacy was satisfactory at the field scale. These findings can be used to develop safe and cost-effective methods for the drone application of pesticides. Full article

Sweetpotato (Ipomoea batatas) is a staple crop of strategic importance in West Africa, particularly in Côte d’Ivoire. However, its productivity is increasingly under threat due to viral diseases. Given the lack of updated epidemiological data over the past three decades, a nationwide survey was conducted in September 2023 across 94 fields in 83 locations covering seven agroecological zones of the country. A total of 221 symptomatic and asymptomatic leaf samples were analyzed using PCR for DNA viruses and RT-PCR for RNA viruses. The overall viral incidence rate calculated was 65.61%, with significant regional variations (35–97.18%, p < 0.001) and notable differences in the severity of symptoms (p = 0.0095). Agroecological zone I was the most affected, while agroecological zones IV and V were the least impacted. Four viruses were identified: cucumber mosaic virus (CMV), sweet potato leaf curl virus (SPLCV), sweet potato feathery mottle virus (SPFMV), and sweet potato chlorotic stunt virus (SPCSV). No badnaviruses were found. CMV was the most common virus found in single infections (43.44%), followed by SPLCV (5.43%). SPFMV and SPCSV were only observed in mixed infections, particularly CMV/SPLCV (14.03%) and CMV/SPFMV (1.81%). Two triple infections were also detected: SPFMV/SPCSV/CMV and SPFMV/SPLCV/CMV. In total, 34 partial coat protein sequences were obtained (28 SPLCV, 4 SPFMV, 1 CMV, 1 SPCSV). Phylogenetic analysis revealed a high similarity between SPLCV isolates characterized in Côte d’Ivoire and those from Burkina Faso, Europe (Spain, Italy), and the Americas (USA, Puerto Rico) with nucleotide identity values ranging from 98% to 100%. The Côte d’Ivoire SPCSV sequence showed 97.92% nucleotide identity with European isolates, whereas SPFMV sequences exhibited greater diversity (77–89% identity) but clustered within the West African lineage. Sweetpotato viral diseases were detected mostly in mixed-cropping fields (66.85%). This work provides the first epidemiological update on sweetpotato viral diseases since 1987 and the first molecular evidence of the nationwide presence of SPLCV and SPCSV in Côte d’Ivoire. Full article

Pollinators play a crucial role in global biodiversity, providing essential ecosystem services such as crop pollination. However, their abundance and diversity have been gradually decreasing in recent years. Despite increasing interest in sustainable agriculture, information on vegetable crops that attract insect pollinators remains limited. We hypothesize that variation in floral traits among vegetable crop cultivars, especially nectar volume, nectar sugar concentration, and pollen characteristics, significantly influences visitation patterns and species composition. To test this, we evaluated multiple cultivars of six vegetable crops (cowpea, sweet potato, eggplant, green bean, mustard, and chickpea) over two years, focusing on five key pollinator groups (honey bees, bumble bees, carpenter bees, sweat bees, and wasps). Cowpea and sweet potato consistently attracted the most pollinators, whereas chickpea attracted the fewest. In 2022, nectar volume was highest in sweet potato (16.45 ± 0.37 µL) and lowest in chickpea (1.18 ± 0.75 µL). Similarly, in 2023, sweet potato recorded the highest nectar volume (8.33 ± 2.95 µL), and chickpea the lowest (0.02 ± 0.01 µL). However, chickpea (31.00 ± 1.58 °Bx) and mustard (30.10 ± 1.12 °Bx) recorded the highest nectar sugar concentration in both years, and chickpea and eggplant produced significantly more pollen grains. A significant positive correlation was observed between nectar volume and pollinator abundance. Comprehensively, this two-year study demonstrates the complex relationship between floral traits and pollinator preferences. These findings offer growers practical guidance on selecting vegetable intercrops that attract specific pollinators, thereby enhancing pollination services, supporting biodiversity, and improving the yield of pollinator-dependent crops. Full article

In the context of increasing economic pressures on global food systems, employing a comprehensive analytical method is crucial for ensuring both efficiency and sustainability in the agriculture sector. Aiming to evaluate cost structures, compare ecological and conventional production systems and identify cost-intensive “hotspots” to support more-efficient practices, the study applies the Life Cycle Cost Analysis (LCCA) methodology to assess the economic performance of the sweet potato (Ipomoea batatas) crop. The primary data were collected from the accounting records and operational documents of an eco-certified vegetable farm in southern Romania. The findings revealed the main cost contributors in the capital cost category—seedling production (5.68%) and selling production (1.39% of the total lifespan cost)—and in the operational cost category—field cultivation (40.81%) and post-harvest costs (32.10% of the total LCC)—which are major cost drivers, highlighting the need for targeted adaptations to enhance cost efficiency and overall sustainability. Full article

The aim of this study was to produce and characterize bioplastics derived from sweet potato peel starch, Aloe vera gel, and eucalyptus essential oil. Starch from sweet potato peels was extracted using a wet method, yielding 3.54%, while eucalyptus oil was obtained via steam distillation, with a yield of 1.4%. In order to assess the influence of Aloe vera and eucalyptus oil concentrations on the properties of bioplastics, a 2^2 factorial design was implemented. Consequently, bioplastic films were produced using the casting technique. As a result, the films appeared brown, translucent, and homogeneous, while also exhibiting a rough surface texture. Mechanical testing revealed that the films possessed a high Young’s modulus of 41.1 ± 11.1 MPa, a maximum tensile strength of 2.1 ± 0.4 MPa, and an elongation at break of 21.6 ± 4.3%. These properties were achieved with a formulation containing 70% w/w Aloe vera, 0.6% w/w eucalyptus oil, and 5% w/w sweet potato peel starch, suggesting a promising eco-friendly alternative to conventional plastics for potential use in packaging applications. Full article

Sweetpotato (Ipomoea batatas L. Lam) production is threatened by complex viral diseases, notably sweet potato virus disease (SPVD) worldwide, which results from co-infection by sweet potato feathery mottle virus (SPFMV) and sweet potato chlorotic stunt virus (SPCSV). This study provides virus-specific transcriptomic insights into the immune responses of three sweetpotato cultivars, ‘Beauregard’, ‘Tanzania’, and ‘New Kawogo’, to SPFMV, SPCSV, and SPVD. Using RNA-seq profiling across three timepoints post-infection at 3, 6, and 12 weeks, we identified distinct virus- and genotype-specific gene expression responses. ‘New Kawogo’ activated early and sustained immune pathways involving redox regulation, transcriptional control, and hormonal signaling in response to both SPCSV and SPFMV, while showing minimal transcriptional disruption under SPVD, reflecting robust tolerance. ‘Beauregard’ exhibited early suppression of immune and metabolic genes, with delayed and disorganized recovery efforts, particularly under SPVD. Defense-related pathways including NBS-LRR signaling, RNA silencing, and hormonal regulation were consistently upregulated in ‘New Kawogo’ and to a lesser extent in ‘Tanzania’, but remained inactive in ‘Beauregard’. This study highlights candidate resistance and susceptibility genes for each virus, providing a molecular basis for developing virus-resilient sweetpotato cultivars through functional genomics and marker-assisted breeding. These findings elucidate the molecular basis of virus resistance in sweetpotato and identify candidate genes for marker-assisted breeding, despite limitations arising from the use of a diploid reference genome and discrete sampling intervals. Full article

Leaf color, as a key ornamental and quality trait in leafy vegetable sweet potato, is controlled by the coordinated regulation of multiple pigment metabolic pathways. To dissect the mechanisms underlying leaf color variation, the integrated transcriptomic and metabolomic analyses were performed on three contrasting phenotypes: green (G), yellow (Y), and purple-red (R). The results showed that purplish-red leaves accumulated the highest levels of anthocyanins (16.36 mg·g⁻¹) and total chlorophyll (2.54 mg·g⁻¹), indicating that the synergistic accumulation of anthocyanins and chlorophyll contributes to their dark pigmentation. In contrast, yellow leaves contained the lowest carotenoid content yet displayed the highest carotenoid-to-chlorophyll ratio (6.44), suggesting that reduced chlorophyll levels coupled with a relatively higher carotenoid proportion underlie the yellow phenotype. Green leaves exhibited a more balanced pigment profile, with a total chlorophyll content of 1.94 mg·g⁻¹. Transcriptomic profiling revealed elevated expression of anthocyanin biosynthetic genes CHS, CHI, F3H, and chlorophyll metabolism-related genes CHLG and CAO in purplish-red leaves, whereas carotenoid biosynthesis genes LCY and CYP97A3 showed specific regulation in yellow leaves. Collectively, these findings demonstrate that leaf color formation in leafy vegetable sweet potato is determined by the relative accumulation of chlorophylls, carotenoids, and anthocyanins, together with differential regulation of their biosynthetic pathways. This work provides novel insights into the molecular basis of leaf color variation and offers a theoretical foundation for genetic improvement of leafy vegetable sweet potato. Full article

This research evaluated the influence of lactic acid bacteria and cellulase, individually or in combination, on the quality of mixed amaranth and sweet potato vine silages. The experiment included four groups: control group with no additives addition (CG), added cellulase group (AS1), added lactic acid bacteria group (AS2) and combined supplementation group (AS3), with five replicates per group. The ensiling period lasted for 60 days. Parameters of silage, including chemical components, fermentation profile, aerobic stability, and in vitro nutrient digestibility, were determined. The results revealed that the quality of amaranth and sweet potato vine mixed silage was improved to a certain degree after addition of two additives individually. Combining these additives observably increased (p < 0.05) the lactic acid and crude protein contents and decreased the pH, ratio of ammonia nitrogen to total nitrogen and neutral detergent fiber content of mixed silage. Compared with the CG and AS1 groups, the number of lactic acid bacteria in the AS3 group increased significantly (p < 0.05), while aerobic bacteria and mold counts showed the opposite tendency. Also, the in vitro dry matter, crude protein and neutral detergent fiber digestibility of the AS3 group were higher (p < 0.05) than those of the CG group. Combined inoculation observably reduced (p < 0.05) the ammonia nitrogen concentration and increased (p < 0.05) the propionic and butyric acid concentrations of mixed silage under in vitro incubation. In summary, the inoculation of lactic acid bacteria and cellulase can enhance the fermentation profile and nutritional values of mixed silage made from amaranth and sweet potato vine, and the best improvement effects are obtained by the combined utilization of the two additives. Full article