Efficiency of Botanical and Chemical Pesticides on the Control of Field Insect Pests under Cowpea Production

The pulse cowpea [Vigna unguiculata (L.) Walp] holds a significant agricultural position in Uganda, ranking fourth among legume crops, following common beans, groundnuts, and soybeans. Known for its versatility, cowpeas are consumable at various developmental stages, from early seedling to maturity. However, the crop faces persistent pest challenges at each stage, leading to substantial yield losses. In Uganda, chemical insecticides are the primary pest control means, but their increased and excessive use raises environmental, health, and economic concerns. This has prompted a quest for alternative and sustainable solutions, prompting an exploration of botanical insecticides. This study, conducted at Makerere University Agricultural Research Institute (MUARIK), aimed to evaluate the effectiveness of three selected botanical insecticides versus four established chemical insecticides for managing cowpea insect pests under field conditions. The treatments included: Carbofuran, Cypermethrin 10% EC, Dimethoate, Pestwin, Pyrethrum ewc , Pyrethrum 5ew, Profenofos 40% Cypermethrin 4% EC mix, and Untreated, arranged in a randomized complete block design with three replications. The significant pests studied were aphids, thrips, pod-sucking bugs, and legume pod borer. Results indicated substantial impacts of the treatments on pest infestation, with Profenofos 40% Cypermethrin 4% EC being the most effective against most pests. The plant parameter, plant height, was significantly affected by treatments in 2016B, while the number of pods was impacted in 2017A. Pestwin, a botanical insecticide blend (containing Azadirachtin indica, Pongamia pinnata, and Ricinus communis extracts) demonstrated superior efficacy against cowpea aphids. Moreover, it positively influenced plant height, number of pods, and pod biomass, surpassing many chemical insecticides. Pestwin’s environmental friendliness positions it as a potential contributor to reducing environmental pollution, making it a promising candidate for inclusion in IPM programs. Overall, the study underscores the importance of exploring botanical alternatives to chemical insecticides for sustainable pest management in cowpea cultivation.

Characterisation of Smallholder Multiple Livestock Species Production Systems in Parts of Lake Victoria Crescent of Central Uganda

A cross-sectional study of 150 purposively selected multiple livestock species farmers was conducted in Central Uganda aimed at distinguishing between mixed and integrated livestock systems. Performance and operational-based challenges misconstrued to cause incorrect comparison between the two systems were considered. Ten multiple-livestock species system with five ruminant species-based and five monogastric species-based combinations were categorised. Poultry, pig, fish, goats and sheep kept in both the 3 and 4-species combinations were considered. Over 80% of the families are male dominated, smallholder and occupying > 1.0 Ha of land. Exotic and crossbred breeds were adopted away from less productive and noncommercial local species. Mixed monogastric-fish systems with monogastric species dominated (P 1000) stock per farm. Stalls dominate pig management systems with 15% of the farmers upgraded to commercial level with (>50) stock per farm. Ineffective livestock policies contribute to inefficient performance of 55% of livestock farmers. In conclusion, mixed livestock systems should be upgraded to integrated livestock systems with input resource synergy for improved production and sustainability.

The effect of abiotic stresses on plant C:N:P homeostasis and their mitigation by silicon

In crop plants, various environmental stresses affect the balance of carbon, nitrogen, and phosphorus(C:N:P), leading to biochemical and physiological alterations and reductions in yield. Silicon(Si) is a beneficial element that alleviates plant stress. Most studies involving silicon have focused on physiological responses, such as improvements in photosynthetic processes, water use efficiency, and antioxidant defense systems. But recent research suggests that stressed plants facing either limited or excessive resources(water, light, nutrients, and toxic elements), strategically employ Si to maintain C:N:P homeostasis, thereby minimizing biomass losses. Understanding the role of Si in mitigating the impact of abiotic stresses on plants by regulating C:N:P homeostasis holds great potential for advancing sustainable agricultural practices in crop production. This review presents recent advances in characterizing the influence of environmental stresses on C:N:P homeostasis, as well as the role of Si in preserving C:N:P equilibrium and attenuating biological damage associated with abiotic stress. It underscores the beneficial effects of Si in sustaining C:N:P homeostasis and increasing yield via improved nutritional efficiency and stress mitigation.

Assessment of Municipal Organic Solid Waste, as a Potential Feedstock for Briquette Production in Kampala, Uganda

The current shortage of energy resources coupled with environmental degradation problems resulting from deforestation in Uganda has contributed to increased demand for renewable energy resources including municipal organic solid waste and agricultural residues. However, organic waste from Municipal Solid Waste (MSW) may contain contaminants that are harmful to public health and the environment. This study determined the heavy metal concentration in MSW in Kampala City, Uganda. Also, the physicochemical properties of briquettes produced from the MSW were compared with charcoal. The waste samples were collected from residential, institutional and market areas over a period of two weeks. They were then analyzed for the presence of heavy metals. Briquettes were made from the bio-waste and were subjected to calorific and proximate analysis. Results indicated that the mean concentrations of Cd, Cr, Cu, Fe, and Pb were 1.25 mg/kg, 2.04 mg/kg, 38.2 mg/kg, 3.97 mg/kg and 1.99 mg/kg respectively while Hg was not detected. The calorific values of briquettes ranged from 8.9 to 15.3 MJ/kg and were lower than those of charcoal. Heavy metal concentrations in bio-waste collected were below the permissible acceptable limits. These findings indicate that the sampled MSW does not pose a health hazard arising from the presence of such heavy metals and therefore could be a safe source of renewable energy.

Utilisation of Non-Conventional Animal Waste as Feeds by Multiple Livestock Species Farmers in Lake Victoria Crescent of Central Uganda

A cross-sectional survey was conducted to establish the utilisation of non-conventional animal waste in multiple livestock species systems. Farmers (150) were selected from four out of ten districts of Central Uganda in Lake Victoria Crescent. A structured questionnaire was used and descriptive analysis showed that over 80% are smallholder farmers on 3.0) years. Household husbands (80%) significantly (P 1.0) as they cause poor livestock health due to pathogens, parasites and toxins which are associated (OD > 1.0) with poor growth, mortality and condemnation of livestock products. The remedy to unsafe non-conventional feeds is to apply effective solar-heating (75%), chemical and ensiling treatment methods. The study showed that there are no significant (P < 0.001) public health risks associated with utilising treated non-conventional feeds instead it improves production and sustainability of multiple livestock species systems.

Diversity and interaction of common bacterial blight disease-causing bacteria(Xanthomonas spp.) with Phaseolus vulgaris L.

Common bacterial blight(CBB) is associated with common bean(Phaseolus vulgaris L.), an important grain legume for human consumption worldwide. The disease, caused by Xanthomonas spp. is spread mainly through seed. This paper focuses on the diversity of X.axonopodis pv. phaseoli and X. fuscans subsp. fuscans and interactions between related bacteria and the bean host. Review has suggested that the diversity and taxonomic studies of these pathogens are not exhaustive, especially in areas where detailed molecular analysis has not been conducted and previous characterizations were based on phenotypic features and PCR-based techniques. Also, no study has confirmed differential pathogenicity on bean genotypes based on compatible versus incompatible reactions. However, isolates react differently to wild and domesticated bean sources of resistance in common bean genetic backgrounds. A systematic approach will be required to investigate global changes in gene expression among different sources of resistance in a common bean background.The bacterial isolates that cause CBB should be functionally characterized using genotypes containing major quantitative trait loci(QTL) for CBB resistance. These studies will increase understanding of resistance and how it is manipulated by pathogens.

Evaluation of Cowpea Genotypes for Resistance to <i>Fusarium redolens</i>in Uganda

Fusarium redolens, a virulent fungus which causes damping off, leaf yellowing, wilting and root rots has recently been devastating cowpea fields in Uganda. This study aimed at identifying cowpea genotypes that are resistant to Fusarium redolens. Therefore, ninety cowpea genotypes were evaluated two times against a highly virulent Fusarium redolens (isolate from Zombo in Paidha district) in the screen house in 2016. Genotype effect was highly significant (P 0.001) for root rot severity. Based on the Index of Susceptibility (IS), three genotypes (Asontem, Dan1 LA and IT89KD-88) remained resistant (IS 3.5) over the two screening periods, 72 moderately resistant (3.5 ≤ IS 6.5) and 11 susceptible (IS ≥ 6.5). Resistance was found to be enhanced by presence of lateral roots above or at the ground level. Further results suggested a difference in genetic control of resistance to root rots and seed rots caused by Fusarium redolens. All the released varieties tested (SECOW 1 T, SECOW 2 W, SECOW 3 B, SECOW 4 W and SECOW 5 T) had moderate resistance to Fusarium redolens. Correlation analysis revealed root rot severity was strongly correlated to disease incidence (+0.64, P 0.001), to proportion of plants with lateral roots (-0.56, P 0.001), to amount of leaf chlorophyll (-0.53, P 0.001) and to proportion of plants that died prematurely due to Fusarium redolens infection (+0.45, P 0.001). No significant correlation was detected between root rot severity and proportion of plants that germinated. The established resistance could be exploited for improvement of farmer preferred cowpea varieties towards Fusarium redolens resistance in Uganda.

Evaluation of Cereal-Legume Cropping on Striga Control and Maize Yield

Striga hermonthica(Del.)Benth is ranked as the number one constraint to maize productivity in Eastern Uganda.The use of trap crops is one of the control measures suggested for farmers with limited resources in Striga infested areas.In this study the main focus was on the effectiveness of intercropping in reducing Striga infestation and hence overall land productivity.The major objective was to identify suitable legumes in the control of Striga.In order to achieve this,on-farm experiments were conducted in Tororo and Busia districts of Eastern Uganda where the effect of the legumes on the Striga prevalence was evaluated.Maize(Zea mays)was intercropped with common beans(Phaseolus vulgaris),soybean(Glycine max)and silver leaf desmodium(Desmodium uncinatum)with sole maize(Z.mays)as the control.Soybean,beans and desmodium decreased the infestation of Striga by 26%,40%and 72%,respectively.There was a significant(p<0.05)difference in the number of emerged Striga and maize yield attained by desmodium and the rest of the legumes.Desmodium was found to be the most effective of the legumes in the control of Striga.

Specificity of Various Mitochondrial DNA (<i>mt</i>DNA), <i>ND5</i>, <i>D-Loop</i>, and <i>Cty-b</i>DNA Primers in Detecting Pig (<i>Sus scrofa</i>) DNA Fragments

Polymerase Chain Reaction (PCR) is an accurate, simple and fast analytical method. This technique is widely used in the identification of meat adulteration and meat-based processed food products. Three Mitochondrial DNA (mt-DNA) primers NADH Dehydrogenase sub unit 5 (ND5), D-Loop, and Cytochrome b (Cyt-b) were tested for their specificity in detecting of pig (Sus scrofa) DNA fragments. DNA genome from 6 meat samples (pork, beef, goat, lamb, and chicken) was amplified by PCR technique using three pairs of primers (ND5, D-Loop, and Cyt-b) and sequenced. The results of amplification using the three primers produced specific DNA bands with the lengths of 232 bp, 951 bp, and 404 bp, respectively. Comparison results with ND5, D-Loop, and Cyt-b gene sequences resulted in similarity values of 100%, 97%, and 99%, respectively. These showed that the mt-DNA primers of ND5, D-Loop, and Cyt-b genes can be recommended as specific primers in detecting pig (Sus scrofa) DNA fragments.

Spatial Differentiation of Small Holder Farmers’ Vulnerability to Climate Change in the Kyoga Plains of Uganda

The paper assessed the variation in the level of vulnerability to climate change among small holder farmers in the Kyoga plains of Uganda. It was hypothesized that there is no spatial variation in the level of vulnerability to climate change among the small holder farmers of different socioeconomic characteristics in the Kyoga plains. It improves the understanding of the different dimensions of vulnerability. This can help to design practical policies and intervention strategies that are specific to the communities’ spatial strata to reduce development imbalances and empower the most vulnerable small holder farmers. The conceptual framework is based on the three elements of vulnerability that is, exposure, sensitivity and adaptive capacity. The cross-sectional survey research design was used to collect both quantitative and qualitative data. Household data were acquired by using a structured questionnaire supported by focussed group discussions while meteorological data were collected using data base review. The study was done in the Kyoga plains agro ecological zone of Uganda comprising of several districts out of which Tororo and Pallisa were picked. Indicators for the components of vulnerability (Exposure, Sensitivity and Adaptive Capacity) were selected by Principle Component Analysis (PCA) and Vulnerability Indices constructed at household level then aggregated at sub county level for correlation using ANOVA. Inter sub county vulnerability index correlation revealed a spatial variation in the level of vulnerability between the different sub counties with Kasodo Sub County in Pallisa being the most vulnerable and Rubongi in Tororo being the least vulnerable. Policy measures and development efforts should therefore focus on place specific strategies of adapting to climate change rather nationwide or region wide strategies. There is also need to refocus policy to nonfarm activities which are less susceptible to climate change and enhance farmers’ income.

Prioritization of Crop Residues for Improving Productivity on Smallholder Dairy Farming Households in the Lake Victoria Crescent, Uganda

Poor nutrition has been identified as a major constraint to productivity in smallholder dairy farming households in Uganda, particularly in Lake Victoria Crescent Agroecological Zone (LVZ). Clarification on nutritional potential of crop residues is central to formulation of sustainable dairy cattle nutrition strategies. Data were collected from 126 randomly selected respondents using structured and semi-structured questionnaires. Farmers’ responses on crop residues utilization, handling, limitations, spatial and temporal variability were collected. Kruskal-Wallis test showed significant differences on utilization of available crop residues (X2 = 50.4, df = 4, p = 0.0001) among farmer’s rankings. It was established that maize stovers were major crop residues utilized and inadequate knowledge to process crop residues was ranked as a major limitation. The study provided basic information on the importance of crop residues. Further research studies should focus on improving the nutritive value of maize stover.

Development of an Integrated Tool for Small-Scale Maize Farming in Uganda

About 62% of the maize produced in developing countries is cultivated manually owing to limited access to appropriate technology. Available technologies perform a single operation, necessitating farmers to buy multiple implements, which is expensive. In this study, an ox-drawn tool integrating a plough, planter and cultivator for small-scale maize farming was developed and its performance evaluated. Planting and cultivating units were designed and fabricated for assembly onto an existing standard ox-plough beam. The integrated tool was tested in the field to assess the effectiveness and efficiency of cultivation and planting of maize. Results showed that the planting unit had an average seed rate of 35.4 kg/ha with a seed damage of 4% and an effective field capacity of 0.15 ha/h at a field efficiency of 87.3%. The cultivating unit had an effective field capacity of 0.1 ha/h and a weeding efficiency of 86%. The efficiency, effectiveness and reliability for field operations are superior to manual operations currently used by farmers and are comparable to single-unit prototypes developed in other countries. This demonstrates the technical feasibility of integrating planting and cultivation units onto an existing mould board plough instead of buying multiple tools.

Phosphorus Fertilizer Rating and Rhizobia Inoculation for Improved Productivity of Cowpea in Northern Uganda

Cowpea (Vigna unguiculata) is an important legume crop in the tropics and subtropical regions of the world. It is mainly grown for its leaves and grains, and to a lesser extent as a fodder crop. Cowpea is considered as the most important food grain legume in the dry savannas of tropical Africa. This study compared the yield of local (Agondire) and improved (SECOW 2W) cowpea varieties grown on an Oxisol. Inorganic P at levels of 0, 10, 20, and 40 kg·ha-1 was tested on each variety with or without rhizobia inoculation. The experiments were set up in a randomized complete block design and replicated thrice during the short and long rains of the 2015/2016 seasons on fifteen fields in Arua district, northern Uganda. Agondire responded significantly (P < 0.05) better than SECOW 2W when high rates of inorganic phosphorus (40 kg P ha-1) were applied. A significant increase of 26.4% and 28.4% in grain yield of Agondire and SECOW 2W, respectively was obtained after inoculation with rhizobia. We concluded that inoculation and P fertilizer application increased the yield of both varieties, but with inoculation, SECOW 2W performs much better at lower P fertilizer rates than Agondire. Therefore, we recommend growing of SECOW 2W under inoculation with 20 kg P ha-1 and an application of 40 kg P ha-1 for Agondire local cowpea variety in northern Uganda.

Cowpea Production Challenges and Contribution to Livelihood in Sub-Saharan Region

Cowpea [Vigna unguiculata (L.) Walp.] is an important grain legume mainly grown in tropical and subtropical regions for vegetables, grains, and fodder. The crop is grown predominantly in the dry savannahs to the Sahel in the fringes of the Sahara Desert where the annual rainfall is around 300 mm or less. Cowpea provides shelter as a cover crop and improves soil fertility by fixing atmospheric nitrogen. Its grain is preferred for high levels of protein, energy, micro-and macronutrients. Cowpea belongs to the family Fabaceae and sub-family Faboidea, and it is a self-pollinating crop with low and narrow genetic diversity, making it susceptible to various environmental factors. Various research projects have been established on cowpea, and as a result, various cowpea germplasm is stored at Africa International Institute of Tropical Agriculture (IITA)—Nigeria, the USDA repository in Griffin, GA (USA), the University of California, Riverside, CA (USA), and at the National Bureau of Plant Genetic Resources (NBPGR) in New Delhi, India. Despite the available germplasms, cowpea productivity remains very low in many countries due to a wide array of abiotic and biotic stresses and socio-economic constraints. This review summarizes some aspects of cowpea, including origin and history, challenges, economic importance, and constraints to production, providing possible useful information for cowpea researchers, agronomists, and producers in SSA.

Optimization of adsorbent dose and contact time for the production of jackfruit waste nutrient-enriched biochar

Raw biochar can be enriched with nutrients from digestates through adsorption producing nutrient-enriched biochar.The nutrient-enriched biochar can be used as a soil amendment to support sustainable agriculture.This study assessed the effect of adsorbent dose and contact time on the jackfruit waste biochar adsorption of essential nutrients of nitrogen,phosphors and potassium from the digestate.Response surface methodology(RSM)using central composite design(CCD)was utilized to optimize the adsorbent dose and contact time during the adsorption process.An adsorbent dose of 20–70 mg/g and contact time range of 48–120 h were used in this study.The optimal adsorbent dose and contact time were found to be 20 mg/g and 114.6 h,respectively.The corresponding optimum nitrogen,phosphorus and potassium adsorbed were 17.44,20.94,and 21.36 mg/g,respectively.Models for the prediction of these values for nitrogen,phosphorus and potassium had R2 values of 0.9801,0.9804 and 0.9843,respectively,and non-significant lack of fit(p<0.05).This indicates the suitability of the models in predicting the adsorption conditions of adsorbent dose and contact time to produce high-quality nutrient-enriched biochar.