Sweet Potato Production Research Articles

Evidence of Rapid Infection of Four Sweetpotato Potyviruses in a Commercial Field in California.

Sweetpotato (Ipomoea batatas Lam.) is grown worldwide and is a staple food in many countries. One of the main constraints for sweetpotato production is cultivar decline, caused by the accumulation of viruses and subsequent losses of storage root yield and quality over years of vegetative propagation. Virus indexing using diagnostic molecular techniques is essential for the detection and identification of the major viruses to avoid cultivar decline, but little information is available on the fate of clean (virus-tested) plant materials after field propagation. In this study, cuttings of three sweetpotato cultivars (Beauregard, Bellevue, and Vermillion) were acquired from a clean propagative material program and planted in commercial field plots in Merced County, California, over multiple growing seasons. In 2021 and 2022, the phytosanitary status of storage roots from different generations of the materials were assessed by reverse transcription quantitative PCR (RT-qPCR) at harvest at the Foundation Plant Services, University of California, Davis. The results showed their rapid infection with four major potyviruses-sweet potato feathery mottle virus, sweet potato virus 2, sweet potato virus C, and sweet potato virus G-over the two seasons. The infection by two to four potyviruses was confirmed by RT-PCR, RT-qPCR, high-throughput sequencing, and biological indexing onto Ipomoea setosa plants for symptoms evaluation.

DETERMINING THE EFFECTIVENESS OF GROWTH REGULATORS IN TECHNOLOGICAL SCHEMES FOR SWEET POTATO (IPOMOEA BATATAS) CULTIVATION IN THE CONDITIONS OF THE FOREST-STEPPE OF UKRAINE

Purpose: To determine the effectiveness of growth regulators in technological schemes for sweet potato cultivation, their impact on tuber yield and quality under the conditions of the Forest-Steppe of Ukraine. Methods: The study was conducted using field and laboratory experiments, as well as computational and statistical calculations. Results: The use of growth regulators DG-16, DAC-6, DG-53 + DG-53A, and fertilizers with growth-stimulating properties such as Gros Cornerist + Gros Amino-Magnesium, Gros Cornerist + Ecoline Phosphite K-Amino significantly increased the number of leaves per sweet potato plant by 24.4–28.7%, stem thickness by 21.6–27.5%, the number of tubers per plant by 31.6–90.8%, and the average tuber weight by 13.0–20.9% relative to the background application of mineral fertilizers. Positive effects of growth regulators and fertilizers were noted on the chlorophyll content in sweet potato leaves (increase of 16.6–22.9% compared to the background), nitrogen content in leaves (excluding DAC-6 and humic fertilizer "Rich Soil," the increase was 9.4–14.3%), phosphorus content (by 9.1–22.7%), potassium content (by 7.8–12.2%), carotene content in leaves (by 13.5–19.3%), and increased antioxidant activity by 10.8–19.3%. Maximum impact on these indicators was provided by DG-16, DG-53 + DG-53A, Gros Cornerist + Ecoline Phosphite K-Amino, and Gros Cornerist + Gros Amino-Magnesium. Maximum yield increase was achieved using DG-16 (an increase of 5.6 t/ha or 36.6%), DG-53 + DG-53A (an increase of 5.7 t/ha or 37.2%), and Gros Cornerist + Ecoline Phosphite K-Amino (an increase of 5.8 t/ha or 37.9%). No significant impact on yield was observed with Timac Agro fertilizer. A positive impact of growth regulators and fertilizers on the biochemical composition of sweet potato tubers was established: Timac Agro fertilizer increased dry matter content (22.97%), DG-16, DAC-6, Gros Cornerist + Gros Amino-Magnesium, and Gros Cornerist + Ecoline Phosphite K-Amino increased vitamin C content (4.88–5.49 mg/100 g), Timac Agro and "Rich Soil" increased carotene content (8.47–9.72 mg/100 g), and DG-16 and Gros Cornerist + Ecoline Phosphite K-Amino increased starch content in tubers (15.28–15.86%). Discussion: The results confirm the effectiveness of growth regulators. Particular attention should be paid to adapting growth regulator application programs to specific growing conditions and crop varieties. Conclusions: The study confirms the potential of using growth regulators and fertilizers with growth-stimulating properties as an effective measure to enhance productivity and quality of sweet potato production under the conditions of the Left-Bank Forest-Steppe of Ukraine.

Characteristics of Cd, As, and Pb Pollution in Farmland Soil and Edible Parts of Chili Pepper and Sweet Potato and Their Health Risk Assessment

To clarify the characteristics of Cd, As, and Pb concentrations in edible parts of crops and farmland soils, a key farmland survey was conducted on the field scale to investigate the characteristics of Cd, As, and Pb in soil and chili pepper （edible parts in the above-ground section） and sweet potato （edible parts under the ground） and assess the health risk of Cd-As-Pb in edible parts of chili pepper and sweet potato to humans in the typical co-contaminated agricultural soils by Cd, As, and Pb from metal smelting and sewage irrigation in North China. The results showed that the agricultural soil from chili pepper and sweet potato fields was co-contaminated by Cd and As at a moderate pollution level. The combined pollution index （2.82） of soil from sweet potato farmland was significantly higher than that from chili pepper fields （2.38） for sweet potato land much nearer to the pollution sources （P<0.05）. However, Cd concentrations in edible parts of chili pepper exceeded the safety limitation of 0.1 mg·kg-1 in the national standard of "Green food pepper products" （NY/T 1711-2020）, but the concentrations of Cd, As, and Pb in edible parts of sweet potato did not exceed the "National food safety standard food pollutant limit" （GB 2762-2022）. Additionally, the bioaccumulation factors （BAFs） of Cd, As, and Pb in edible parts of chili pepper to soil were markedly higher than those of sweet potatoes, especially for Cd, which showed the maximum of the BAFs for chili pepper. Therefore, BAFs could be the key factor in Cd accumulation in the fruits of chili peppers. The risk assessment of Cd and As as the carcinogenic elements in edible parts of chili pepper and sweet potato to human health demonstrated that Cd in the whole fruit of chili pepper had posed a significant health risk to adults （Ri>1×10-4）, and it was an acceptable level of health risk from Cd and As in edible parts of both crops to children. The non-carcinogenic element of Pb in the fruits of both crops did not cause health risks to adults or children. In summary, the chili pepper products from this co-contaminated farmland by Cd and As would pose risks to human health, and the sweet potato products would cause acceptable health risks to humans.

Effect of Vine Harvesting Frequency on Sweetpotato Root Yield Components and Gross Income in Southern Mozambique

Sweetpotato is widely produced by smallholder farmers in Mozambique with average yield of 7.3 t/ha. One of the challenges in sweetpotato production system is inadequate seed during the rainy season resulting in low productivity. The few sweetpotato seed multipliers (Decentralized vine multipliers (DVMs)) resort to several vine harvesting frequency to meet farmers seed requirements at the peak of demand. Repeated vine harvesting contributes to sweetpotato root yield reduction. The objective of the study was to evaluate the effect of vine harvesting frequency on sweetpotato yield components. Three experiments were set up in three farmers’ fields in Vilankulos district inhambane province in Southern Mozambique in the 2021/2022 and 2022/2023 cropping seasons with a sweetpotato variety Esther. The experiments were set up in randomized complete block design with three replications in each farmer’s field. The treatments were no vine harvesting (control), harvesting only once at 8 weeks after planting (WAP), harvesting twice at 8 and 12 WAP, and harvesting three times at 8, 12, and 16 WAP. Total storage root yield, number of roots per plant, root diameter, and root length were measured in each treatment. Results show that storage root yield was significantly higher in control (22.1 t/ha) and harvesting once (17.8 t/ha) compared to harvesting twice (11.8 t/ha) and three times (9 t/ha) (P < 0.05). Additional harvesting from one to two resulted in 33.7% yield decline. Vine harvesting twice resulted in 46.6% storage root yield decline compared to the control treatment. The same observation was noted for the number of roots per plant, where five roots per plant were observed both in no harvesting and harvesting once treatments. A 40% decline in the number of roots per plant was observed when vine harvesting frequency was increased from one to two. No treatment effect was observed on the root diameter. Increasing vine harvesting frequency from one to two or one to three resulted in a 14.7% income loss from sales of both vines and roots. Vine multipliers are recommended to harvest vines for use as planting material only once if they want to benefit from the roots for consumption or commercialization.

Identification of viruses infecting sweetpotato (Ipomoea batatas Lam.) in Benin

Abstract Sweetpotato (Ipomoea batatas) production in sub-Saharan Africa is affected by viral diseases caused by several interacting viruses, including Potyvirus and Sweepovirus. This research was conducted with the aim of determining the incidence and characterizing sweetpotato viruses in Benin. A field survey was conducted in 16 districts of Benin, and 138 plant samples were collected with symptoms from 35 fields. Viruses were identified using molecular diagnoses and Sanger sequencing. The symptoms of the detected viruses were then evaluated by grafting infected sweetpotato scions onto healthy Ipomoea setosa plants, using two scions per plant. Eight viruses were detected from samples: cucumber mosaic virus (CMV), sweet potato chlorotic stunt virus (SPCSV), sweet potato virus G, sweet potato feathery mottle virus, sweet potato chlorotic fleck virus, sweet potato latent virus (SPLV) with sweet potato leaf curl virus (SPLCV) and sweet potato symptomless virus 1 (SPSMV-1) predominating at 70 and 13% incidence, respectively. Co-infections and mixed infections, such as SPSMV-1 + CMV, SPLCV + CMV, SPSMV-1 + SPLCV, CMV + SPCSV, SPSMV-1 + CMV + SPLCV, and SPSMV-1 + CMV + SPLCV + SPLV + SPLCV, have been observed. This study is the first to document the significant presence of SPSMV-1 and SPLCV in sweetpotato fields in Benin. The findings could provide a valuable foundation for further research into the impact of these viruses on sweetpotato productivity in Benin. Additionally, the findings of this study could assist agricultural policymakers in developing strategies to control sweetpotato viruses in the region.

Disease Segmentation in Purple Sweet Potato Images Using Yolov7

Purple sweet potato is a very important plant in many parts of the world and a major crop in tropical and subtropical climates. Its cultivation can significantly increase production and consumption, and it is beneficial for the nutritional status of people in both rural and urban areas. However, purple sweet potatoes are susceptible to disease outbreaks, which can cause substantial losses to the agricultural industry. To prevent the spread of these diseases and minimize financial losses, it is crucial for farmers to identify purple sweet potato diseases as early as possible. Utilizing deep learning technology to separate areas of purple sweet potatoes marked with disease can effectively address this problem. In this study, researchers employed a segmentation method using the YOLOv7 algorithm. The study's results demonstrated a mean Average Precision (mAP) value of 98.6% from a dataset of 1500 images, divided into two classes: healthy sweet potatoes and diseased sweet potatoes with tuber rot. The mAP value for healthy sweet potatoes was 96.1%, while the mAP for diseased sweet potatoes with tuber rot was 98.6%. The YOLOv7 method, therefore, produces high accuracy values for the segmentation of purple sweet potato diseases. This research significantly contributes to agriculture by enhancing the productivity and quality of sweet potato harvests and can assist farmers in improving the efficiency and sustainability of purple sweet potato production.

Influence of Elevated Potassium Fertilization on Structural and Functional Properties of Sweet Potato Root Tuber Starch.

Nine sweet potato varieties with different flesh colors were cultivated under uniform environmental conditions with potassium (K) fertilizer treatments at levels of 0, 22.5, and 45 kg/ha. The structural and functional properties of the starches were subsequently analyzed. The soluble sugar content in the dry root tuber increased, with higher K levels in most varieties. Amylose content decreased in Sushu16 but increased in Ningzishu1, with no significant differences observed in other varieties across different K levels. Elevated K levels had no effect on starch protein content, crystalline type, or gelatinization enthalpy. The impact of K fertilizer on starch thermal and pasting properties varied among the varieties. PLSR and PLS-DA analyses revealed that genotype background was the primary factor influencing starch properties. This research will provide a reference for the improvement of sweet potato production quality and efficiency and a scientific basis for the cultivation and utilization of sweet potato root tubers.

Potential Utility of Bacillus amyloliquefaciens SFB-1 as a Biocontrol Agent for Sweetpotato Black Rot Caused by Ceratocystis fimbriata.

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.

Impact of NPSB fertilizer on yield of orange-fleshed sweet potato (Ipomoea batatas (L.) Lam.) varieties in Southern Ethiopia's agro-ecological zones

Root and tuber crops, particularly sweet potatoes, are vital to global food security, yet their potential for enhancing household nutrition and income remains largely untapped. Orange-fleshed sweet potato (OFSP) varieties are rich in pro-vitamin A, crucial for health. Despite their significance in Ethiopia, yields are often low due to inadequate location-specific fertilizer recommendations and limited access to high-yielding varieties. This study aimed to determine the optimal blended NPSB fertilizer rates and high-yielding OFSP varieties in the contrasting environments of Wolaita and Gamo zones, where these crops are staples. We evaluated three OFSP varieties (Alamura, Dilla, and Kabode) and four NPSB rates (0, 79.5, 159, and 238.5 kg ha−1 in a 3x4 factorial experiment using a randomized complete block design (RCBD) with three replications during the 2022 cropping season. Data on root yield and yield components were analyzed using the GLM procedure in SAS 9.2. Partial budget analysis and agronomic efficiency were also computed. Results showed that marketable root yield and root dry matter were significantly affected by the interaction of site, fertilizer rates, and OFSP varieties. The highest marketable root yield (49.84 t ha−1 and net benefit (342,856.6 ETB ha−1) were achieved with the Kabode variety at 238.5 kg NPSB in Arba Minch, while the same variety yielded the highest net benefit from 159 kg NPSB in Areka. The highest agronomic efficiency was recorded at 159 kg NPSB and 79 kg NPSB in Arba Minch (174.71) and Areka (288.67), respectively, indicating a negative relationship between net benefit, agronomic efficiency, and increasing NPSB rates. In conclusion, cultivating the Kabode variety with 159 kg ha−1 NPSB in Arba Minch and 79.5 kg ha−1 NPSB in Areka is recommended for enhancing sweet potato productivity, thereby improving food security and nutritional benefits for smallholder farmers in the region.

Characterization of virus species associated with sweet potato virus disease in Costa Rica and riboprobe development for its rapid detection

AbstractSweet potato (Ipomoea batatas) is a crucial crop for food security and economic stability in many regions, including Costa Rica. This study aimed to assess the prevalence and genetic diversity of two major viruses associated with sweet potato virus disease (SPVD) in Costa Rica: sweet potato feathery mottle virus (SPFMV) and sweet potato chlorotic stunt virus (SPCSV). A total of 50 leaf samples displaying typical viral disease symptoms were collected from major sweet potato‐growing regions. Using multiplex reverse transcription (RT)‐PCR, SPFMV was detected in 82% of the samples and SPCSV in 52%, with a coinfection rate of 48%. Genetic analysis revealed that SPFMV isolates belonged predominantly to phylogenetic group B, while SPCSV isolates clustered with the West African (WA) strain. The low genetic diversity within these viral populations suggests a limited number of initial infection events followed by local spread. Riboprobe technology was evaluated as an alternative to RT‐PCR for virus detection. While the riboprobes for SPFMV demonstrated sensitivity comparable to RT‐PCR, the SPCSV riboprobes showed slightly lower sensitivity, particularly when using crude leaf extracts. Despite this, riboprobes offer significant advantages in terms of cost and ease of use for large‐scale screening. Our findings underscore the need for robust diagnostic and management strategies to control SPVD and highlight the importance of continuous monitoring and research to mitigate the impact of viral diseases on sweet potato production in Costa Rica. These insights contribute to the global understanding of SPVD and support collaborative efforts in plant pathology research.

Optimization of golden snail egg liquid organic fertilizer in sweet potato cultivation: towards sustainable agriculture and increased production

Abstract Increasing sweet potato production is often done by applying excessive amounts of chemical fertilizer which causes environmental degradation. The use of liquid organic fertilizer made from golden snail eggs, which are pests, is an alternative to increase sweet potato production while controlling golden snail pests using eco-friendly methods. This research aims to analyse the optimal concentration and time interval for applying golden snail eggs liquid organic fertilizer (GSE-LOF) to increase sweet potato production. Sei Mencirim Village in Deli Serdang Regency served as the research site in August – December 2023. The research design used was a Randomized Block Design, the first factor was concentration of GSE-LOF (0; 37.5; 75 and 112.5 mL/L) and second factor was the time interval of applying (5; 10 and 15 days). Data of the research showed that concentration of GSE-LOF had a noteworthy impact on length and weight of tuber and shoot fresh weight. The time interval for applying GSE-LOF had significant impact on shoot fresh weight. Interaction between concentration and time interval for application of GSE-LOF had a noteworthy impact on the shoot fresh weight. It is recommended to apply GSE-LOF with a concentration of 37.5 mL/L and an application interval of 15 days.

Detection of Viruses and Elimination of Sweet Potato Feathery Mottle Virus in High-Yielding Varieties of Sweet Potato (Ipomoea batatas) from Ethiopia

Sweet potato (Ipomoea batatas L. Lam.) is a major source of food in many parts of Ethiopia. In recent years, viral diseases have become the main threat to sweet potato production in Ethiopia. Previous virus survey studies carried out from 1986 to 2020 reported eight viruses infecting sweet potato in Ethiopia. Consequently, obtaining and multiplying virus-free planting materials have been difficult for farmers and commercial multipliers. This study was conducted to detect viruses infecting the five sweet potato varieties used as source plants and compare the virus elimination efficiency between meristem cultures from untreated and heat-treated mother plants and production of virus-free sweet-potato-planting materials. Seven common viruses were tested for, using grafting to Ipomoea setosa, enzyme-linked immunosorbent assay (ELISA) and reverse-transcription polymerase chain reaction (RT–PCR) before and after elimination procedures as screening and confirmatory methods. The sweet potato feathery mottle virus (SPFMV) elimination efficiencies of meristem cultures from untreated (grown at 25 ± 1 °C) and heat-treated (grown at 39 ± 1 °C) potted plants of sweet potato varieties were evaluated and compared. Sweet potato feathery mottle virus (SPFMV) was detected in 12 of the 15 source plants tested. Triple infections of SPFMV, sweet potato chlorotic stunt virus (SPCSV), and sweet potato virus C (SPVC) were detected in one of the fifteen plants. This study reports the detection of SPVC for the first time in sweet potato plants from Ethiopia. The cutting of meristems from heat-treated plants further increased the percentage of virus-free plantlets by ca 10% to ca 16%, depending on the plant variety. Elimination efficiency also seemed to vary among varieties: the greatest difference was observed for ‘Tola’, and the least difference was observed for ‘Guntute’. The present study provided protocols for detecting viruses and generating virus-free sweet-potato-planting materials in Ethiopia.

Assessing pesticide residue levels in sweetpotato roots and slips treated with fungicides for management of southern blight and circular spot disease caused by Agroathelia rolfsii.

Since 1971, North Carolina (NC) has been the leading sweetpotato-producing state in the United States (US) and is now producing more than half of the nation's annual output. Due to the high demand for US sweetpotatoes from international markets, NC allocates roughly 40% of its sweetpotatoes for export. However, low fungicide residue limits in primary export markets restricts the ability for NC producers to apply fungicides for disease management during sweetpotato production. Agroathelia rolfsii, the causal agent of southern blight and circular spot, is an important pathogen of sweetpotato. Field experiments were conducted in 2022 and 2023 to quantify the residue amount of various active ingredients and transplant-only vs. bedding and transplant applications when managing A. rolfsii in the field. High-performance liquid chromatography analyses of root and vine samples confirmed that none of the tested active ingredients and application timings resulted in residue numbers exceeding the limits of export markets, except for roots treated with thiabendazole. Results from this study provide information for development of application practices with acceptable residue levels for export markets while effectively managing diseases caused by A. rolfsii.

Major Insect Pests of Sweet Potatoes in Brazil and the United States, with Information on Crop Production and Regulatory Pest Management.

The sweet potato [Ipomoea batatas (L.) Lam] is considered one of the most important crops in the world as food, fodder, and raw material for starch and alcohol production. Sweet potato consumption and demand for its value-added products have increased significantly over the past two decades, leading to new cultivars, expansion in acreage, and increased demand in the United States and its export markets. Due to its health benefits, sweet potato production has multiplied over the past decade in Brazil, promoting food security and economic development in rural areas. Their adaptability and nutritional value make them a food of great importance for Brazil. As pest attacks and disease infection are the main limiting aspects that often cause yield loss and quality degradation in sweet potatoes, there is a great demand to develop effective defense strategies to maintain productivity. There is a critical need for research into non-pesticide control approaches that can provide safe, cost-effective, sustainable, and environmentally friendly pest and disease management techniques. Pests which feed on roots have trade implications worldwide. For example, sweet potato tuber shipments infested with the sweet potato weevil are generally not allowed for trade in North and South America.

Analysis of Technical Efficiency on Orange Fleshed Sweet Potatoes Production Among the Smallholder Farmers in Migori County Kenya

Sweet potatoes (<i>Ipomea batatas </i>L.), particularly the orange fleshed variety, have become increasingly popular due to their ability to thrive in various environmental conditions with minimal inputs. Orange fleshed sweet potatoes (OFSPs) show potential for productivity, yet smallholder farmers in Kenya still struggle to maximize their yields. The factors influencing OFSP production efficiency among these farmers in Western Kenya have not been thoroughly examined. This study evaluated the technical efficiency of OFSP production among smallholder farmers in Migori County. Using a descriptive research design, a sample of 225 OFSP farmers was randomly selected by a cluster sampling technique. Data was collected through a structured questionnaire on inputs and selected socio-economic factors. The data was analyzed using the frontier stochastic model in STATA. Smallholder farmers estimated mean technical efficiency was 77.82% significant variables were; size of the land, availability of planting vines, access to hired labour, gender of the household decision maker, farming experience, household size, land ownership status, participation in training programs and extension services, and proximity to markets, indicating a need to improve OFSP production by 22.18%. These findings suggest that to reduce inefficiencies among smallholder OFSP farmers, targeted training programs are needed to enhance farmers' agronomic knowledge specific to OFSP production. Further, policy interventions should prioritize the provision of extension services to support and improve the performance of OFSP smallholder farmers.

Business Feasibility Analysis of Processed Sweet Potato Products at MSME Karya Indah Bandorasa Wetan

Sweet potato processing is a vital part of the local economy. In this study, the business costs incurred and feasibility of processing sweet potato product businesses in the Malaysian Small and Medium Enterprises (MSME) Karya Indah in Bandorasa Wetan are analyzed. The research is based on a census technique, namely, the MSME Karyan Wetans, which is used as the population and sample in the research. The business costs are calculated to calculate various costs associated with running a business consisting of fixed costs and variable costs. The acceptance feasibility ratio was found to be 1.455, so it is greater than 1 and is in the feasible and feasible category. This research offers practical guidance for MSMEs in assessing their operational efficiency and helps business owners make informed decisions about investment and expansion. Furthermore, it contributes to the broader understanding of sustainable business practices in the agricultural processing sector, specifically focusing on sweet potato products. Moreover, analyzing the impact of technological improvements or more efficient production methods on reducing costs and increasing productivity could provide valuable insights for enhancing business operations.

Comparative Study of Income of Sweet Potato Farmers' in Different Trade Channels in Bandorasa Wetan Village, Cilimus District, Kuningan Regency

This study aims to analyze the income of sweet potato farmers in Bandorasa Wetan Village, Kuningan Regency, by comparing different trading channels, specifically sales to middlemen and direct sales to the processing industry. Sweet potato farming plays a crucial role in supporting local and national economies, with Kuningan being a major sweet potato production area in West Java. Using a quantitative comparative approach with survey techniques, data was collected from 83 farmers, with 49 selling to middlemen and 34 to the industry. The results show that the average income of farmers selling to the industry (IDR 3,468,222) is significantly higher than those selling to middlemen (IDR 2,812,569), as evidenced by the independent sample test (p = 0.000). However, income from industry sales shows greater variability. This research contributes by highlighting the income disparities across trading channels, offering valuable insights for farmers and stakeholders in optimizing trading practices to maximize profitability. Future research should explore factors influencing channel selection, including market conditions and trading strategies, to enhance the overall sustainability and profitability of sweet potato farming.

Effects of Paecilomyces lilacinus and Bacillus pumilus on stem nematode and rhizosphere bacterial communities of sweet potato

Stem nematode (Ditylenchus destructor Thorne) is considered one of the most economically devastating species affecting sweet potato production. Biocontrol offers a sustainable strategy for nematode control. This study conducted a pot experiment to evaluate the biocontrol efficacy of Paecilomyces lilacinus CS-Z and Bacillus pumilus Y-26 against the stem nematode, as well as to examine their influence on the bacterial communities in the sweet potato rhizosphere. The findings indicated that B.pumilus Y-26 and P.lilacinus CS-Z exhibited respective suppression rates of 82.9% and 85.1% against the stem nematode, while also stimulating sweet potato plant growth. Both high-throughput sequencing and Biolog analysis revealed distinct impacts of the treatments on the bacterial communities. At the phylum level, B.pumilus Y-26 enhanced the abundance of Actinobacteria but reduced the abundance of Cyanobacteria, with P.lilacinus CS-Z exhibiting similar effects. Additionally, the treatment with B.pumilus Y-26 resulted in increased abundances of Crossiella, Gaiella, Bacillus, and Streptomyces at the genus level, while the treatment with P.lilacinus CS-Z showed increased abundances of Crossiella and Streptomyces. In contrast, the abundance of Pseudarthrobacter was reduced in the treatment with B.pumilus Y-26. Conversely, the application of the nematicide fosthiazate exhibited minor influence on the bacterial community. The findings indicated that the application of P.lilacinus CS-Z and B.pumilus Y-26 led to an increase in the relative abundances of beneficial microorganisms, including Gaiella, Bacillus, and Streptomyces, in the rhizosphere soil. In conclusion, P.lilacinus CS-Z and B.pumilus Y-26 demonstrated their potential as environmentally friendly biocontrol agents for managing stem nematode disease of sweet potato.

The Impact of Nitrogen Levels on the Growth, Development, and Yield of Orange-fleshed Sweet Potatoes (Ipomoea batatas L.)

Nitrogen (N) is one of the most important fertilizers in agriculture because it promotes the growth of plants and the uptake of other plant nutrients. This nutrient plays a significant role in determining the yield and nutrient composition of sweet potato root tubers. Therefore, this study aimed to determine the optimum application rate of N in sweet potatoes to maximize yields and increase growth efficiency. Four levels of N (50, 100, 150, and 200 kg/ha) were applied as treatments. A randomized complete block design was used, and each treatment was replicated five times. Vine length, leaf length, stem thickness, and chlorophyll content were measured weekly, and the storage root yield was determined at the end of the experiment. The results showed a significant effect of the N treatments on plant growth, chlorophyll content, vine length, leaf area index and storage root yield. The chlorophyll content and vine length increased with an increase in the N rate. However, an inverse relationship was observed between storage root yield and N rates; the highest yield was recorded for the 50 kg/ha N treatment and the lowest yield was recorded for the 200 kg/ha N applied. Therefore, a rate of 50 to 100 kg/ha N is recommended for the production of orange-fleshed sweet potatoes.

Increasing Production Of Purple Sweet Potato (Ipomoea Batatas Poir) By Treatment Of Shimmer Fertilizer and Kaliphos

The title of the research was “Increased Production of Purple Sweet Potato (Ipomoea batatas poir) with Vermicompost and Kaliphos Fertilizer Treatment”. This research was carried out for 4 months in the experimental garden of the Faculty of Agriculture, Islamic University of Riau. The purpose of this study was to determine the effect of interaction and the main effect of increasing purple sweet potato production by the treatment of vermicompost and Kaliphos fertilizer. The design used was a completely randomized factorial design consisting of two factors. The first factor was vermicompost fertilizer (K) with 4 levels: 0. 550. 1.100. 1,650 g/bundle. The second factor is Kaliphos fertilizer: 0.5. 10. 15 g/plant. Parameters observed were the number of tubers per plant (fruit), tuber weight per tuber (g), tuber weight per plant (kg), tuber production per mound (kg), harvest index, and fresh chestnut weight per plant (kg). The last observational data were analyzed statistically and continued with the BNJ follow-up test at level 5 %. The results of the study conclude that the interaction effect of vermicompost and caliphos fertilizer is significant on tuber weight per tuber, tuber weight per plant, tuber production per mound, harvest index, and fresh chestnut weight per plant. The best treatment dose was 1,650 g/mound and Kaliphos 15 g/plant (K3L3). The main effect of vermicompost fertilizer is real in all treatments. The best treatment dose is 1,650 g/mound (K3). The main effect of caliphos fertilizer is significant for all treatments. The best treatment dose is 15 g/plant (L3).