The number of effective herbicides available to farmers is steadily decreasing due to increasing herbicide resistance. It seems very important to address and effectively deal with the main weed management challenges (low crop yield and environmental pollution) by investigating the potential of newly introduced materials, such as biocompatible polymer-based nanoparticles. The current review aims to encourage agricultural or environmental researchers to conduct new research on the synthesis and application of modified herbicides, such as nanoherbicides, for application in weed management and to provide a comprehensive foundation on the topic. Such nanosystems could help with the promotion of the controlled release of active ingredients and extend their action time, resulting in a reduction in dose and application number; improve the physical and chemical characteristics of the herbicide to increase foliar adhesion; prevent degradation that results from environmental factors (such as sunlight, temperature, microorganisms, or pH); and decrease herbicide leaching and contamination of the environment. Furthermore, it has been indicated that some polymeric nanocarriers can penetrate biological barriers, including membranes and plant cell walls, and translocate across vascular tissues, resulting in a more efficient delivery of active ingredients. Poly(epsilon-caprolactone) is a biocompatible material that is easily decomposable by enzymes and fungi. PCL nanoparticles could be applied as nanocarriers of herbicides in agriculture due to their low toxicity, their potential for large-scale synthesis from inexpensive materials, their ability to dissolve herbicides, their high loading capacity, and their ability to help minimize the chemical decomposition of herbicides.

The emergence of pests and diseases, including the maize streak virus, leaf blight, the African stem borer, and gray leaf spot, poses a persistent threat to maize production (Zea mays L. cv: DMR-ESR-Yellow) around the world. A field experiment was conducted at the School of Agriculture experimental site, Njala University, Sierra Leone, during a two-year period (2020–2021) to assess the effects of green manure on pest and disease incidence and severity as well as growth and yield parameters of maize. The experiment was laid out in a randomized complete block design (RCBD) with three replications and four treatments: Cal. 3 t.ha⁻¹, Cal. 6 t.h⁻¹, Pan. 3 t.h⁻¹, Pan 6 t.ha⁻¹ and a control plot amended with 200 kg ha⁻¹ of N (urea) and NPK 15:15:15 ha⁻¹ split application. The study showed that gray leaf spot damage was the most severe infection among all treatments. Therefore, the effects of the most severe disease and pest of maize in Sierra Leone can be minimized by applying green manure. Moreover, results reveal that Calopogonium- Pueraria mixture amended plots showed significant performance in the measured growth parameters viz. highest leaf number, large leaf area stem girth, superior plant height, best ear height (64.6–78.5 cm), higher cob yield (1.2–1.4 t.ha⁻¹) ear (1.8–2.1 t.ha⁻¹) and dry grain yield (0.5–0.7 ha⁻¹). Panicum green manure results showed that prompt and adequate application, as well as decomposition of green manures, is imperative for the successful conservation and sustainability of maize farming systems. The findings of this research could improve the efficiency of green manure use in pest, disease, and crop management systems.

Field and storage trials were conducted to assess the response of exotic and local yam genotypes to major diseases (anthracnose, yam mosaic virus (YMV) and dry rot) and pests (i.e., mealy bug and nematodes) for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Njala Agricultural Research Centre (NARC) experimental site in Sierra Leone during two cropping seasons, 2020 and 2021. A total of 113 genotypes of yam comprising 15 D. rotundata, 4 D. prahensilis, 7 D. esculenta, 74 D. alata, 7 D. bulbifera, and 4 D. cayenensis were assessed. Results showed a significant (p < 0.001) linear relationship between yield and disease severity among yam genotypes. In-field disease (anthracnose and yam mosaic virus) infection accounted for 38% of the total variation observed in the fresh tuber yield. Findings on fresh tuber yield revealed that for every ton increase in yield of yams, anthracnose and YMV severities at five months after planting (MAP) decreased by 0.5 and 3.1 units, respectively. About 30 genotypes had low infection of disease, of which two belonged to D. rotundata (TDr 205 and TDr 96/00587), two belonged to D. prahensilis (PSLY074-13 and BMSLY085-13), three belonged to D. bulbifera (MOSLY022-12, MOSLY024-12 and KESLY09-12), and one belonged to D. esculenta (WRSLY083-13), while the remaining were D. alata. About 27 genotypes had intermediate infection, and 14 had high disease susceptibility, all of which belonged to D. alata. Storage disease infection had a highly significant (p < 0.002) linear relationship among yam genotypes. Dry rot, mealy bug, and nematode infection accounted for 15.1% of the total variation in fresh tuber weight loss. The findings were relevant for selecting parents with complementary traits of interest targeted at yam population improvement.

Background. Global climate change and excessive nitrogen application has become a significant issue and inevitably threatens sustainable wheat production, not only with direct negative effects on crop growth but also with profound impacts on biology and pest and disease management. Purpose. This review addresses the current challenges, namely the negative effects of climate change and the forms and excess of nitrogen-rich fertilizers on the development of fungal diseases in wheat, as well as management strategies. Materials and methods. To achieve the stated objective of the study, the scientific literature published during the last 20 years on the impacts of climate change and the forms and excesses of nitrogen fertilizers on the development of fungal diseases and on the yield of wheat were reviewed. Results. Thus, in mitigating these challenges, it is necessary to optimize the dose of nitrogen fertilizers, apply nitrogen in the form of nitrate, ammonium sulphate, ammonium nitrate, and coated urea fertilizers, to use silicate fertilizers such as calcium, magnesium, and potassium silicate, and to perform a long rotation of wheat through perennial legumes and leguminous crops, as well as to develop, through genome editing, varieties with high yield potential, resistant to biotic and abiotic stresses, and of good end-use quality, or plant new cereals that have needs for heat and a longer reproductive growth period. Conclusion. To develop an effective agricultural management strategy, future research should be based on the study of the interactions among crops, pests, pathogens and farming system under climate change, taking into account all parameters such as temperature increase and CO2, extreme precipitation, etc. A sufficient number of results must be published to be able to draw meaningful conclusions.

New advances of nano-enabled weed management: using poly(epsilon-caprolactone)-based nanoherbicides. A review