Journal of Agricultural Science, Issue: Vol.18, No.9

Effectiveness of Two Herbicide Application Methods for Common Sunflower (Helianthus annuus L.) Control in Northern Tamaulipas, México

Thu, 13 Aug 2026 01:38:01 +0000

Herbicide application using drones has increased considerably worldwide because of its operational efficiency and ease of use. The objective of this study was to compare the effectiveness of two herbicide application methods, a tractor-mounted sprayer and a drone, for the control of common sunflower (Helianthus annuus L.) in northern Tamaulipas, Mexico. The experiment was conducted in a fallow field in Río Bravo, Tamaulipas. Glyphosate, 2,4-D, ammonium glufosinate, and paraquat were applied at rates of 726, 574.8, 400, and 400 g a.i. ha^-1, respectively, using both application methods. Weed control was evaluated using the European Weed Research Society (EWRS) scale, and spray coverage was assessed with water-sensitive paper cards. Data were analyzed using analysis of variance (ANOVA). Spray coverage with the tractor-mounted sprayer ranged from 40.8 to 53.6%, whereas drone application ranged from 1.9 to 2.6%. The tractor-mounted sprayer provided slightly greater weed control with paraquat, glyphosate, and ammonium glufosinate, whereas 2,4-D was more effective when applied by drone. Overall, both application methods achieved comparable levels of weed control, demonstrating that drone-based herbicide application is a viable alternative for pre-plant weed management. In addition to providing effective weed control, drone application offers greater operational flexibility, reduces reliance on conventional ground equipment, and has the potential to improve water-use efficiency because it requires lower spray volumes than conventional ground sprayers.

Biological Control Agents and Resistance Inducers for Managing Anthracnose, Common Bacterial Blight, and Angular Leaf Spot in Common Bean

Thu, 13 Aug 2026 01:43:59 +0000

Xanthomonas citri pv. fuscans, Colletotrichum lindemuthianum, and Pseudocercospora griseola are among the most important pathogens affecting common bean production, causing significant yield losses worldwide. Despite previous reports on biological control agents, there is limited evidence on the integrated performance of Bacillus amyloliquefaciens and Trichoderma harzianum combined with resistance inducers under field conditions, particularly across different cultivars and growing seasons. This study evaluated the field efficacy of biological control agents and resistance inducers for managing common bacterial blight (CBB), anthracnose, and angular leaf spot in bean cultivars, and their effects on yield components and normalized difference vegetation index (NDVI). We hypothesized that seed treatment combined with foliar application at V3 would provide superior disease suppression and yield improvement compared with seed treatment alone. The treatments included B. amyloliquefaciens, T. harzianum, citric acid, and sulfur, applied either as seed treatment (ST) or as seed treatment combined with foliar application at the V3 growth stage (ST+V3). The bean cultivars IPR Campos Gerais and IPR Tangará were used across two dry-season and one rainy-season trials conducted in 2023 at IDR-Paraná, Londrina, PR, Brazil. Application rates followed the manufacturers’ recommendations for both seed and foliar treatments. Disease severity, spectral reflectance indices, and yield components were evaluated. All treatments significantly reduced disease severity, with particularly pronounced effects on CBB in both cultivars. Across application methods, B. amyloliquefaciens and T. harzianum improved yield components and grain yield and reduced the proportion of shriveled seeds. In IPR Tangará, grain yield was negatively correlated with CBB severity. Furthermore, B. amyloliquefaciens consistently resulted in a lower incidence of CBB, anthracnose, and angular leaf spot compared with untreated controls, regardless of cultivar. These findings demonstrate the potential of biological control agents and resistance inducers as components of integrated disease management strategies to improve disease control and yield performance in common bean systems. These findings demonstrate the potential of biological control agents and resistance inducers as components of integrated disease management in common bean, though multi-location validation is required before large-scale recommendations can be made.

Field and Molecular Assessment of Cassava Viral Pandemics in Four Provinces of North-Eastern Democratic Republic of Congo

Thu, 13 Aug 2026 01:55:56 +0000

Cassava mosaic disease (CMD) and Cassava brown streak disease (CBSD) are the major biotic constraints that destroy cassava tuberous production, reduce cassava productivity, and negatively impact food security of households in DRC. Epidemic status of those viral diseases was evaluated in 400 cassava fields in the North-Eastern DRC. Assessment was conducted along main roads at 10 km intervals, with 30 plants evaluated per field using an X-shaped transect. The epidemiological parameters evaluated included disease incidence, severity, source of infection, whitefly abundance, and molecular incidence. In addition, foliar and stems symptoms, root necrosis were considered for CBSD diagnostic. A total of 54 cassava varieties were identified in farmers’ fields, of which only six were improved varieties; notably, these improved varieties were the most affected by CBSD. Both diseases were widespread with heavy epidemic pressure in the prospected provinces. CMD field evaluation was as follows: Bas-Uele (I:77.9%, S:3), Tshopo (I:75%, S:3), Haut-Uele (I:50.4%, S:2) and Ituri (I:30.5%, S:3). However, CBSD was prevalent in Ituri (I:23.8%, S:2), Haut-Uele (I:1.4%, S:2) and in Tshopo (I:1.3%, S:2). The PCR analysis of 140 leaf samples revealed a lower molecular incidence than that observed during field assessments. This discrepancy may reflect limitations in diagnostic sensitivity, low viral titers, or the presence of genetically diverse viral populations. No CBSD was identified by PCR in Bas-Uele Province. Whitefly density per plant was relatively high in Ituri (18) followed by Bas-Uele (9), Tshopo (7) and Haut-Uele (6). The major factor of these viral pandemics spread is the use of infected cassava planting materials. To limit this trend, an urgent reliable healthy cassava system is needed in DRC.

Efficiency of Traps, Phytosanitary Measures, and Climate in the Monitoring and Control of the Carambola Fruit Fly (Bactrocera carambolae) in a Production Area in the State of Pará, Brazil

Thu, 13 Aug 2026 02:02:02 +0000

The adoption of eradication and control measures is essential to mitigate phytosanitary problems that restrict fruit exports, particularly in regions where fruit growing plays a key socioeconomic role. This study evaluated the efficiency of traps and phytosanitary measures, as well as the influence of climatic variables on the monitoring and control of the carambola fruit fly (Bactrocera carambolae) in Terra Santa, Pará, Brazil. The research was conducted in the Lower Amazon mesoregion between 2023 and 2024, and comprised four stages: (i) characterization of the experimental area and monitoring periods; (ii) pest detection and monitoring survey; (iii) assessment of B. carambolae captures in Jackson and McPhail traps; and (iv) application of eradication-oriented phytosanitary measures. Results indicated that captures in Jackson traps were positively correlated with maximum temperature (r = 0.090) and solar irradiance (r = 0.013). Jackson traps also showed higher efficiency for eradication detection (r = 0.193) compared to McPhail traps (r = 0.081). Key control measures included the male annihilation technique, application of toxic baits on host plants, soil spraying, use of SPLAT formulation, and collection/destruction of infested fruits. Overall, Jackson traps proved more effective in capturing B. carambolae, with maximum temperature and solar irradiance identified as critical climatic factors influencing pest development and dispersal.

Source Use Intensity and Knowledge Use in Smallholder Advisory Systems: Evidence From Ugandan Innovation Platforms

Fri, 14 Aug 2026 00:39:08 +0000

In pluralistic advisory environments, farmers often receive information from multiple sources. However, agricultural science still needs stronger evidence on whether the breadth or the frequency of source use is more closely associated with knowledge use in farm-management decisions. Using Ugandan coffee innovation platforms as an empirical case, this study examined whether active source portfolio diversity and source-use intensity were differently associated with knowledge use. The analysis used respondent-level cross-sectional survey data set from 214 farmers. From 15 active source items, two portfolio indicators were constructed: portfolio diversity, defined as the number of sources used at least sometimes, and source intensity, defined as average frequency of source use. Knowledge use was assessed across production, harvesting, postharvest handling and processing, and marketing. The four items formed a defensible composite (Cronbach’s alpha = 0.758, omega = 0.760; first eigenvalue = 2.320). Bivariate analysis revealed positive associations for both diversity and intensity with knowledge use, though intensity showed the stronger association (r = 0.588) than diversity at the main threshold of three or more sources (r = 0.369). Separate adjusted models confirmed both diversity (b = 0.118, 95% CI [0.063, 0.172]) and intensity (b = 1.174, 95% CI [0.898, 1.449]) as positive predictors. In joint models, intensity remained strongly positive (b = 1.609, 95% CI [1.222, 1.996]), while diversity weakened and was not robust under the stricter thresholds. The findings suggest that regular engagement with useful advisory and learning sources may matter more for knowledge use than simply expanding the number of sources.

Reduced Stimulation of Striga hermonthica Seed Germination by Root Exudates of Maseno EH14 Hybrid Maize Variety

Thu, 13 Aug 2026 02:10:35 +0000

The parasitic Striga hermonthica weed causes serious yield losses to maize (Zea mays L.) in sub-Saharan Africa. Striga seeds are stimulated to germinate by strigolactones produced by the host plants. Maseno EH14 and EH11 hybrid maize varieties have been bred for Striga and foliar diseases tolerance respectively but their tolerance mechanisms have not been elucidated. The study investigated the activity and chemical composition of root exudates of the maize varieties alongside a Striga susceptible PHB3253 variety on Striga seed germination. Germination assays were carried out using crude maize root exudates alongside the synthetic GR24 stimulant. Germination frequencies and radicle lengths were analyzed using ImageJ v. 1.45. Data were subjected to ANOVA through the linear model of SAS and means were separated using LSD_0.05. The root exudates were also freeze-dried and subjected to HPLC analysis. Maseno EH14 had the lowest Striga seed germination at 20.08% compared to PHB3253 at 51%, EH11 at 37.54% and GR24 at 76.96%. Maseno EH14 also had the shortest radicle length at 0.38 mm against PHB3253 at 0.82 mm, EH11 at 0.71 mm, and GR24 at 0.91 mm. HPLC analysis showed PHB3253 and Maseno EH11 exuding mainly 5-Deoxystrigol and two other compounds while EH14 had three peaks that did not correspond to any of the standard strigolactones used in the analysis. Maseno EH14 therefore exhibits tolerance to Striga hermonthica due to low stimulation of Striga seed germination, and the absence of the more stable 5-Deoxystrigol strigolactone which is commonly associated with Striga susceptibility in maize.

Factors Influencing the Use of Agricultural Machinery by Kenyan Maize Farmers

Thu, 13 Aug 2026 02:37:00 +0000

Smallholder maize farming in Bungoma County, Kenya, continues to face labour shortages, low productivity, and inefficient farm operations, increasing the need for mechanization among smallholder farmers. However, the use of agricultural machinery remains constrained by limited awareness, inadequate credit access, and financial limitations. This study examined factors influencing the use of tractors, chisel ploughs, sprayers, and sheller machines among 330 smallholder maize farmers in Bungoma County using a multivariate probit (MVP) model. The findings revealed significant complementarities among machinery use decisions, justifying the suitability of the MVP approach (Wald χ² = 157.08, p < 0.001). Age positively influenced the use of tractors (β = 0.0369, p < 0.01) and shellers (β = 0.0272, p < 0.05), indicating that older farmers are more likely to adopt mechanization due to accumulated farming experience and financial stability. Education significantly increased the likelihood of using tractors (β = 0.3062, p < 0.01), sprayers (β = 0.3885, p < 0.01), and shellers (β = 0.2083, p < 0.10). Awareness of mechanization strongly enhanced the use of all machinery types, including tractors (β = 1.5499, p < 0.01) and shellers (β = 1.7988, p < 0.01). Cooperative membership positively affected the use of chisel ploughs (β = 0.5709, p < 0.01) and shellers (β = 0.7379, p < 0.01), while access to market information significantly increased sprayer use (β = 0.3635, p < 0.05). The study recommends strengthening extension services, cooperative-based mechanization models, and affordable credit systems to enhance mechanization uptake and improve maize productivity among smallholder farmers.

Reviewer Acknowledgements for Journal of Agricultural Science, Vol. 18, No. 9

Thu, 13 Aug 2026 02:15:31 +0000

Reviewer acknowledgements for Journal of Agricultural Science, Vol. 18, No. 9, 2026.