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Item Review of Scientific Advances and Importance of Biochar for Agricultural and Industrial Uses(International Journal of Bioresource Science, 2024-12-07) Mwadalu, Riziki; Ndufa, James; Maitra, Sagar; Gweyi-Onyango, Joseph; Gitari, HarunBiochar has been known as an effective soil amendment with capabilities of boosting soil moisture storage, increasing soil fertility, and enhancing crop productivity. Biochar also has the potential for industrial use for wastewater treatment, water purification, steel making, building insulation, and air pollution control. The current metadata analysis evaluated the importance of biochar for agricultural and industrial uses and its relevance for use in Kenya. A total of 120 reference materials comprising journal papers, conference proceedings, and book chapters were used. Numerous studies conducted across the globe have documented the positive effects of biochar in increasing available soil nutrients (increased by 28.6% and phosphorus by 2 folds), lowering bulk density by 3-31%, enhancing soil moisture storage by 18-108%, and boosting microbial activities in the soil thus enhancing nutrient cycling. The metadata analysis also showed that biochar can reduce CO2 emissions by up to 33% thereby mitigating climate change. Biochar equally increased maize yield by 32-135% and rice yield by 8.5-10.7%. The review also showed that biochar can play a crucial role in different industrial uses such as wastewater treatment, steel making, and water purification. Some of the main impediments to the adoption of biochar were; the lack of a regulatory framework to govern the sector and the lack of a decision support system for use by end users.Item Synergetic Effect of Potassium, Biochar and Cattle Manure on the Growth and Yield of Maize, and Soil Physio-Chemical Characteristics(MDPI, 2024-11-24) Shao, Zeqiang; Zhang, Xiuzhi; Nasar, Jamal; Gitari, HarunBiochar (BC) and cattle manure (CM) are carbon-nutrient-rich organic substances and have long been used to improve crop yield and soil fertility. Nevertheless, their combined effect with potassium (K) fertilizer remains unknown. Against the previous context, a 2-year (2021–2022) field experiment was conducted to assess the effect of K fertilization coupled with BC and CM on the growth and yield of maize and soil physio-chemical characteristics. The K application combined with BC and CM increased (p ≤ 0.05) the majority of the growth indices of maize crop compared with CK. Compared with CK, the combined application of K (60 kg K ha−1) with BC and CM resulted in an increased number of seeds cob−1 by up to 451 and 465, and up to 383 and 396, the 1000-seed weight up to 22 and 23 g, and up to 27 and 34 g, and the grain yield up to 1979 and 2900 and up to 3240 and 3341 kg ha−1, respectively, in 2021 and 2022. The integrated application of these inputs increased the chlorophyll of maize crops by 29 and 36% and by 30 and 44%, respectively, in 2021 and 2022. Such application also increased the photosynthetic activities of maize such as transpiration rate (Tr), stomatal conductance (Gs), and photosynthetic rate (Pn) by 21 and 23%, 143 and 110%, and by 64 and 66% in 2021 and by 19 and 30%, 163 and 118%, and by 63 and 72% in 2022. Similarly, the combined application of K, BC, and CM increased the K uptake of maize due to an increase in the soil extractable K. Equally, soil total N and organic matter improved under the combined application of K, BC, and CM. However, it did not affect the soil extractable P in 2021 but increased it in 2022. Conversely, these applications reduced (p < 0.05) the soil electrical conductivity, sodium adsorption ratio, and bulk density. This suggests that K fertilization combined with BC and CM enhances the growth and yield of maize by improving the soil nutrients availability, increasing soil organic matter, and enhancing soil structure and moisture retention.Item Spatial Distribution of Soil Organic Carbon Stocks, and Soil Total Nitrogen in Central Equatorial State, South Sudan(International Journal of Bioresource Science, 2024-12-06) Malo, Meshack Oguna; Ladu, John Leju Celestino; Mukeka, Joseph; Maitra, Sagar; Gitari, Harun; Onyango, Joseph GweyiThe composition of soil organic carbon (SOC) and soil organic nitrogen (SON) is imperative to soil health in different agroecological zones globally. The proliferation of anthropogenic activities triggers the nitrogen and carbon stocks in soils. This study presents the spatial distribution of SOC and SON in six counties in Central Equatoria State, South Sudan counties. This study sought to determine the effect of pastoral activities on SOC and SON. We collected the soil samples within a 12-14 km radius from specific areas including congregation, grazing, degraded, water points, and agricultural land. The soil was collected at depths of 0–10 cm, 10–20 cm, and 20–30 cm respectively. The results indicate that land use activities had varied impacts on SOC and SON at different depths. The results showed that the interactive effects of the three sites and land uses differed in soil organic carbon (SOC) under different soil depths, which varied from 0.3 to 5.3%. The grazing area also recorded a higher SOC than the other land use types under 0-10 cm soil depth. The means showed that the SOC in the deep soils (20-30 cm) was lower than the surface soils in all the areas and land uses. The interactive effects of the districts and land uses differed in soil organic carbon (SOC) under different soil depths, which varied from 0.3 to 5.3%. The highest mean SOC of 5.73% was recorded in 0-10 depth in Kajokeji in the grazing area. The grazing area also recorded a higher SOC than the other land use types under 0-10 cm soil depth. The means showed that the SOC in the deep soils 20-30 cm was lower than the surface soils in all the areas and land uses. The results thus underscore that study areas and land use activity could impact the SOC and SON directly or indirectly.Item Co-Composting to Close the Cycle of Resources during Rose Cultivation in Kenya: An Agronomic and Pesticide Residue Assessment(Elsevier, 2024-08-08) Nijs, E.A. de; Onyango, J. Gweyi; Bol, R.; Hall, R.L. van; Ntinyari, W.; Tietema, A.Recycling green waste through composting is a promising practice for the transition towards a bio-based circular economy in the floricultural sector of Africa, especially for Kenya where cut flower export accounts for nearly 14 % of its total export value in 2017. Rose waste is a large waste stream, but its intrinsic properties make it challenging to recycle. Composting on commercial scale was studied on a rose farm near Lake Naivasha, (Kenya). Three mixtures were examined: (1) rose waste (RW) only, (2) 80 % RW + 20 % tomato waste and (3) 90 % RW + 10 % mature rose compost. Trapezoidal piles of approximately 4000 kg green waste were composted following the turned windrow approach, samples were taken at six occasions. The nine-month composting study, including pesticide fate assessment, showed consistent performance across tested mixtures. All mixtures resulted in mature and stable compost with C/N ratios below 10 and a high fertilizing potential, meeting international sanitation requirements. Final average volume reduction was 82 %, total N values ranged between 8.1 and 8.9 mg g−1 compost and pH values were alkaline (8.0–8.3). Out of the approximately 50 pesticides commonly used in rose cultivation only 8–12 pesticides could be detected in the matured composts with the highest contribution of flubendiamide and fluopyram. Scenario analysis showed the feasibility of closing the resource cycle in the African floricultural sector via continuous crop rotation over eight years with an amendment rate of 11.5 kg per m2. Overall, this study provided straightforward implementable practices for rose waste management, which facilitates the re-use of valuable green waste in Africa and thereby contributes to the transition towards a global circular economy.Item Optimising Plant Density and Nitrogen Rates for Effective Powdery Mildew Management in Garden Peas(African Crop Science Journal, 2025-05) Muriithi, M.; Mwangi, M.; Karanja, A.; Matheri, F.Garden pea (Pisum sativum L.) is crucial in sub-Saharan Africa (SSA), serving both local consumption and export. Its production, however, faces significant challenges mainly due to powdery mildew (Erysiphe pisi), which is responsible for yield losses of up 60%. The objective of this study was to determine the optimum point of N fertiliser interaction with planting densities, for control of powdery mildew disease in garden pea. Treatments included N rates at 0, 15, 30, and 60 kg-1; mode of application (foliar or root base) and plant density(45 cm x 15 cm and 45 cm x 7.5 cm). The treatments were laid out in a randomised complete block design (RCBD), replicated four times. Results showed that disease severity and incidence increased along with N application and plant density; however, yield reduced at both high N rate (60 kg N ha-1) and in the control (0 kg N ha-1) rates. Fertiliser intensity significantly influenced powdery mildew occurrence, pod yield, and plant branches in garden peas, underscoring the need for strategic N management and planting density for sustainable disease management. The study identified 30 kg N ha-1 applied either by foliar or root application, together with 45 cm x 15 cm plant spacing as the most effective combination; which effectively reduced powdery mildew incidence; while improving crop yieldItem Can Fungal Endophytes Suppress Trialeurodes Vaporariorum and the Transmission of Tomato Infectious Chlorosis and Chlorosis Viruses in Field Conditions?(Frontiers in Cellular and Infection Microbiology, 2025-02) Paweer, Marial Makur Zechariah; Namikoye, Everlyne Samita; Nchore, Shem Bonuke; Akutse, Komivi SenyoField trials were conducted for two seasons in two experimental sites (Mwea in Kirinyaga and Ngoliba in Kiambu counties of Kenya) to assess the efficacy of fungal endophytes Hypocrea lixii F3ST1 and Trichoderma asperellum M2RT4 in the control of Trialeurodes vaporariorum vector of tomato infectious chlorosis virus (TICV) and tomato chlorosis virus (ToCV) through seeds inoculation. TICV and ToCV’s disease incidence, severity and the yield were also evaluated. All the fungal endophytes successfully colonized all the tomato plant parts, but the highest root colonization was observed in H. lixii F3ST1 compared to the T. asperellum M2RT4 in both seasons. The number of nymphs was significantly lower in the endophytically colonized tomato plants than the control treatments in all the seasons and at both sites. However, the lowest number of nymphs was recorded in H. lixii F3ST1 compared to T. asperellum M2RT4. On the other hand, the TICV and ToCV disease incidence and severity rates were lower in endophytically colonized tomato crops compared to the control plots. This could be attributed to the reduction in the virus replication and lower feeding ability of T. vaporariorum that was characterized by less excretion of honeydew causing sooty mold. However, no significant difference was observed in ToCV disease severity rates among the treatments and across the seasons. The yield was significantly higher in endophyte plots than the control treatments in both sites and across the two seasons. This study demonstrates that H. lixii F3ST1 and T. asperellum M2RT4 endophytically colonized tomato plants and conferred systemic resistance against T. vaporariorum vector, and significantly reduced the transmission of TICV and ToCV, contributing to high reduction of both diseases’ incidence and severity in the field. However, further studies are warranted to confirm these results at large scale trialsItem The Role of Young Scientists in Promoting Genome Editing for Sustainable Agriculture and Food Systems in Africa(Frontiers in Sustainable Food Systems, 2025-03) Kitenge, Seleman Yusuph; Nkhabindze, Bongani; Ratemo, Billy Omboki; Dada, Susan Angira; Ogbimi, Ejeoghene Rita; Karikari, Benjamin; Nuaila, Valter N. A.; Toili, Mary Esther Muyoka; Ndudzo, Abigarl; Adetunji, Charles Oluwaseun; Fotabong, Estherine; Akinbo, OlalekanClimate change together with Africa’s growing population, threaten food systems. Improving youth participation in agricultural research and innovation, especially the use of genome editing (GEd) technology, will help address this inequality and ensure that Africa capitalizes on its youth to foster its food systems. This policy brief explores how young scientists are promoting GEd for sustainable agricultural and food systems in Africa. The brief made recommendations to improve on the youth participation in policy making processes and tackling public scepticism to promote the adoption of GEd. It concludes by calling for African governments to make a concerted effort to ensure young scientists are well-informed, supported, and actively involved in the advancement of GEd technology in agriculture in Africa. Climate change and various anthropogenic factors, coupled with Africa’s rapidly growing population, pose significant threats to food systems and the agricultural sector. Challenges such as inadequate youth engagement in agricultural research, lack of funding and a lack of modern infrastructure hinder the continent’s ability to achieve food security. Improving youth participation, particularly in the application of genome editing (GEd) technology, is essential for addressing these disparities and ensuring that Africa leverages its youthful demographic to enhance its food systems. This policy brief explores the pivotal role young scientists play in promoting GEd for sustainable agricultural and food systems in Africa. It highlights specific gaps, such as the need for increased investment in state-of-the-art laboratories, incubators, and mentorship programs, as well as financial assistance and scholarships for aspiring and budding researchers. Furthermore, the brief emphasizes the importance of youth involvement in policy-making processes and the necessity of addressing public scepticism to facilitate the adoption of GEd. By fostering an inclusive environment where young scientists are well-informed and actively engaged, African governments can harness the innovative potential of this demographic to drive agricultural advancements. The brief concludes with a call to action for African governments to prioritize the support and development of young scientists in the advancement of homegrown GEd technology, contributing to the sustainability and resilience of agriculture and food systems across the continent.Item Unpacking the benefits of black soldier fly frass fertilizer towards nematode suppression and potato production(frontiers, 2025) Anedo,Emmanuel O.; Beesigamukama,Dennis; Mochoge,Benson; Korir, Nicholas K.; Solveig Haukeland; Xavier Cheseto; Nyongesa,Moses; Pwaipwai,Patrick; Sevgan Subramanian; Abdou Tenkouano; Betty Kibaara; Tanga,Chrysantus M.Potato production is hindered by soil degradation and nematode infestation. Mineral fertilizers and synthetic nematicides are costly and cause negative impacts on humans and the environment, while organic fertilizers are less effective for soil health and nematode management. This study demonstrates the contribution of black soldier fly frass fertilizer (BSFFF) in nematode suppression and potato productivity when compared to commercial mineral fertilizer, organic fertilizer (SAFI), and nematicide. The on-farm experiments consisted of eight treatments: BSFFF, SAFI, BSFFF+5%chitin, NPK+nematicide, 50%BSFFF+50%NPK, 50%SAFI+50%NPK, 50%BSFFF+5% chitin+50%NPK, and control (unfertilized soil). Results revealed that all fertilizer treatments significantly increased potato growth, number of tubers (34 – 61%), and tuber yield (20 – 72%) relative to the control. Application of BSFFF+5% chitin produced 9 – 28% higher tubers per plant compared to other treatments. Over 26% higher tuber yield was achieved using BSFFF+5% chitin compared to NPK+nematicide treatment. Soil amendment with BSFFF+5% chitin caused 5–35% higher reduction in the number of cysts per 200 g soil-1 compared to NPK +nematicide and SAFI treatments. The same treatment reduced the PCN reproduction rate by 20% and 75% compared to NPK + nematicide and SAFI, respectively. Both BSFFF and NPK+nematicide treatments achieved comparable suppression of the number of eggs and infective juveniles (J2) per cyst-1 and eggs g-1 of soil. However, BSFFF+5% chitin reduced the number of eggs and J2 per cyst-1 and eggs g-1 of soil by 55–92% compared to SAFI. Our findings demonstrate that chitin-fortified BSFFF can significantly contribute to potato cyst nematode suppression and boost potato yields in smallholder farming...Item Investigating the effect of seaweed extract and humic acid on the quantitative and qualitative performance of sugar beet under water stress(Islamic Azad University, 2025-01-16) Ajirlu, Tawakkel Fekri1; Farzaneh, Salim; Tobe, Ahmed; Sharifi, Rauf Seyed; Nouri, Mohsen; Gitari, Harun; Heydarzadeh, SaeidWater stress is one of the major limitations in crop production and performance stability. This study aimed to investigate the effect of biological stimulants on the quantitative and qualitative performance of sugar beet under drought stress. A field experiment was conducted to evaluate the effect of irrigation regimes (irrigation after 80, 160, 240, and 320 mm of water evaporation from the class A pan) and the application of biological stimulants at 5 levels (control, seaweed extract at 3 and 6 kg ha⁻¹, humic acid at 3 and 6 kg ha⁻¹). The results showed that the highest gross sugar (15.99%), extraction coefficient (77.31%), and pure sugar (12.37%) were obtained under irrigation conditions after 240 mm of water evaporation, while the highest levels of sodium (16.4%) and nitrogen (3%) were ob tained under irrigation conditions after 320 mm of water evaporation. The use of biological stimulants caused a significant increase in gross sugar and pure sugar and a reduction in sodium and nitrogen compared with the control treatment. The maximum root yield (74.06 t ha⁻¹) and pure sugar yield (8.42 t ha⁻¹) were obtained in the foliar application of 6 kg ha⁻¹ of humic acid under irrigation conditions after 80 mm of water evaporation. In general, 6 kg ha⁻¹ of seaweed extract and 3 kg ha⁻¹ of humic acid under moisture stress conditions reduced sugar beet root impurities such as sodium and harmful nitrogen. As a result, the efficiency of root sugar extraction was significantly improved, and the sugar percentage of molasses was reducedItem Optimizing Sunflower Production Through the Use of GIS-Based Soil Fertility Management Strategy(Taylor & Francis Group, 2024-08) Nungula, Emmanuely Z.; Massawe, Boniface J.; Chappa, Luciana R.; Nhunda, Daniel M.; Seleiman, Mahmoud F.; Ali, Nawab; Gitari, Harun I.This study aimed to use a GIS-based approach in producing soil fertility maps and utilize the spatial data on achieving site-specific management of major nutrients in Morogoro, Tanzania. Soil samples were collected in six mapping units and analyzed for chemical properties such as pH, cation exchange capacity and electrical conductivity. ArcGIS 10.8 was used to produce nutrient variability maps of organic carbon, available P, total nitrogen and exchangeable K, Ca and Mg using the Inverse Distance Weight (IDW) interpolation method. The soil pH values ranged from 5.5 to 7.2. OC varied between 1.2 and 4.9g kg−1, TN ranged from low to medium (1.0 to 5.0g kg−1) whereas Av. P varied between l3.3 and 14.3mg kg−1. Exchangeable K, Ca and Mg had ranges (in cmol kg−1) of between 0.1 to 0.8 (low to medium), 3.8 to 15.6 (low to high) and 0.3 to 0.5 (low), cmol kg−1. The recommended amounts were 74, 44, 36, 35 and 12kg ha−1 for N, P2O5, K2O, MgO and CaO, respectively. Conducting soil analysis is key for monitoring the amount of nutrients that are available in the soil at time and space, to achieve site-specific nutrient management.Item Soil- and Foliar-Applied Silicon and Nitrogen Supply Affect Nutrient Uptake, Allocation, and Stoichiometry in Arabica Coffee Plants(Taylor anf Francis, 2024-10) Parecido, Renan J.; Soratto, Rogério P.; Perdoná, Marcos J.; Gitari, Harun I.Silicon (Si) application may affect the plant response to nitrogen (N), possibly by changing the uptake, concentration, and partitioning of nutrients in plant tissues; however, this has not yet been proven in Arabica coffee plants. The effects of Si application methods [no Si, soil-applied soluble Si (168 mg Si L−1), and foliar-applied soluble Si (two application of 2 mg Si plant−1)] and N levels (0 and 80 mg N L−1) on biomass production and partitioning and uptake, partitioning, and stoichiometry of nutrients and Si in young Arabica coffee plants grown under greenhouse conditions were evaluated. Nitrogen fertilization increased the biomass production and uptake of all nutrients; however, reduced the concentrations of K, Ca, Mg, S, Mn, and Si in the leaves, Si in the stems, and K, Mg, and S in the roots of coffee plants as a dilution effect. In the presence of N, soil-applied Si increased the concentrations of Zn in the leaves and Ca and Si in the stems, the uptake of K, S, and Si, and the Si:N ratio. Foliar- applied Si increased the concentrations of N, P, K, and Zn in the leaves and Ca and Si in the stems, as well as the total uptake of K and Si and the Si:N ratio in coffee plants, being more evident in the N fertilization presence. This study unraveled that, especially when it was soil-applied, Si altered the nutrient uptake, allocation, and stoichiometric ratios with N, with a consequent increase in biomass production of young coffee plants fertilized with N.Item Impacts of selected Climate Smart Agricultural Practices on African Indigenous Vegetables in Kenyan drylands(African Phytosanitary Journal, 2024) Muthama, Eric; Najma, Dharani; Samita, Namikoye; Karanja, RebeccaClimate change has had significant impacts on the cultivation of African Indigenous Vegetables (AIVs) resulting in insufficient yields and food insecurity. African indigenous vegetables are important food crops used in combating malnutrition and food insecurity. The AIVs have the potential to provide nutrition and sustain smallholder farmers’ livelihoods. However, little is known about the impacts of ClimateSmart Agriculture Practices (CSAPs) on the yield levels in AIVs. This study was therefore conducted to evaluate the impacts of selected CSAPs on the yield levels in cowpeas (Vigna unguiculata. L) and black nightshade (Solanum nigrum. L) in Kenyan drylands. Six treatments consisting of organic manure, commercial organic fertilizers, irrigation, mulching, inorganic fertilizers and controls were used. Research plots measuring 3m by 3m were set out in a randomized complete block design and sowed with certified cowpeas seeds and well-established black nightshade seedlings. Treatments were applied at land preparation and at 7 days after crop germination. Data was collected on plant height at vegetative stage and the overall primary yield at crop maturity. Analysis of variance (ANOVA) was conducted on the quantitative data collected and analyzed using Genstat software. Post hoc analysis was carried out for significant means using Tukey’s Honest Significant Difference (HSD) test at p≤0.05. The results revealed significant differences in both the plant height and primary yield across all treatments (p≤0.05). The AIV yield levels were significantly influenced by the CSAPs products used. Plots treated with organic manure, mulching and commercial organic fertilizers had significantly higher yields. Control plots had the least amount of yields.Item Reproductive Potential of Fall Armyworm Spodoptera Frugiperda (J.E. Smith) and Effects of Feeding on Diverse Maize Genotypes under Artificial Infestation(Frontiers in Insect Science, 2022-09) Anyanda, Geoffrey N.; Anani, Y. Bruce; Makumbi, Dan; Ahonsi, Monday; Kahuthia-Gathu, Ruth; Namikoye, Samita E.; Beyene, Yoseph; Prasanna, B. M.Fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) has become a major threat to maize production in Africa. In this study, six maize genotypes were assessed for their resistance to FAW under artificial infestation in both laboratory and net house conditions. These included two FAW-tolerant hybrids (CKHFAW180294 and CKH191221), two commercial hybrids (WE2115 and CKH10717), and two open-pollinated varieties (ZM523 and KDV4). Larval development time and reproductive potential were assessed on maize leaves in the laboratory and a life table for FAW was constructed. The maize genotypes were also artificially infested with three FAW neonates at two phenological stages (V5 and V7) and reproductive stage (R1) in the net house. Leaf and ear damage scores were recorded on a scale of 1–9. Larval development time varied significantly between maize genotypes with the highest on CKH191221 (16.4 days) and the lowest on KDV4 (13.7 days). The intrinsic rate of natural increase for life tables varied from 0.24 on CKH191221 to 0.41 on KDV4. Mean generation time of FAW ranged from 17.6 to 22.8 days on KDV4 and CKH191221, respectively. Foliar damage was the lowest on CKH191221, and the highest on KDV4 at V7 infestation stage in week 1. CKH191221 had the lowest ear damage score, whereas ZM523 had the highest scores at V5 infestation stage. The highest and lowest yield reductions were observed on ZM523 (64%) at V7 infestation stage and CKHFAW180294 (6%) at R1 infestation stage, respectively. The results indicated the potential for developing tropical mid-altitude maize germplasm with native genetic resistance to FAW.Item Adoption of Green Building Practices in Langata, Nairobi CityCounty, Kenya(International Journal of Innovative Science and Research Technology, 2024) Chebet, Mercy; Gweyi J.; Kitur E.The increase in greenhouse gas emissions in the atmosphere is a threat to biodiversity. This challenge is being solved by introducing green building practices such as making use of natural lighting, use of solar heating systems, using materials like bamboo which are long-lasting and renewable which aid in reducing energy, water, natural resource consumption and improving waste management in buildings which human beings spend most of their time. Although past research has established a correlation between the level of stakeholder awareness and the rate of uptake of green building technologies, this postulate had not been tested in Nairobi City County. Thus, this study focused on adoption of green building practices in Langata, Nairobi County, Kenya. The study adopted a survey research design; utilizing both quantitative and qualitative methods of data collection including semi-structured questionnaires, inspection checklist and interview schedules.The variables assessed were; the level of green building awareness of construction practitioners, regulatory measures of green building practices and the environmental sustainability indicators ofgreen building technology. The sample size comprised of 100 samples from a total population of 13,126 comprised of construction players including quantity surveyors, construction practitioners and project managers and residential buildings built between 2010 and 2020, two floors and above were the focus of the study. The collected data was analyzed using Microsoft Excel version 13 and SPSS version 25. To test hypotheses, regression analysis was performed. The level of awareness as variables had R-Square of .106, F calculated of 10.357 and p≤.002; The Regulatory measures had R-Square of .172, F- calculated of 15.644 and p≤.003 and environmental sustainability had R Square of .241, F- calculated of 13.742 and p≤.002 on adoption of green building technology in Langata Nairobi County, Kenya. The findings indicated that data was significant and alternative hypotheses were acceptable to be statistically significant. The findings depicted that majority of construction workers were not aware of green building, Kenya Green Building Society and neither were they trained on green building. Regulatory measures were implemented at a moderate extent but green building policies had not been incorporated in the current construction guidelines. The study also showed that green building practices such as waste management, energyand water efficiency are being observed well. The conclusion is that most respondents do not clearly understand green building technology, implementation of the already set green building policies is still a challenge and there is a great change in people’s attitude towards building sustainably. It is recommended that more awareness and training should be done, regulations established and enforced and government should provide incentives to encourage green building technologies. The findings of the study provide additional literature on the subject matter for further research. It also helps policy makers in formulating policies which may enhance the uptakeof green building technology in the study area.Item Big Opportunities for Tiny Bugs: Rush to Boost Laying Hen Performance using Black Soldier Fly Larvae Meal(Journal of Economic Entomology, 2023-12) Munga, Leonard M.; Osuga, Isaac M.; Munguti, Jonathan M.; Subramanian, Sevgan; Kidoido, Michael K.; Ghemoh, Janice C.; Mwendia, Charles M.; TangaChrysantus M.Rising feed cost challenges due to expensive conventional protein sources continue to make headlines in Africa causing drops in profit margins. We assessed the impact of insect (Hermetia illucens Linnaeus larvae meal, HILM) protein as a substitute for soybean meal and sunflower seed cake on layer chicken performance and profitability. Our results showed that apart from the growers, chicks (12.37 g/bird) and layer hens (2.02 g/bird) fed diets with 75% HILM inclusion levels had significantly higher average daily weight gain. The average daily feed intake (ADFI) and feed conversion ratio (FCR) varied significantly when the chicks and layer hens were provided with the HILM-based diets. For the chicks and layer hens, the lowest ADFI and FCR were observed in birds subjected to diets with 75% and 100% HILM compared to the growers fed diets with 50% HILM. Significantly higher egg production was observed for layer hens fed diets containing 75% of HILM throughout the first (87.41%) and second (83.05%) phase production cycles. Layer hens fed HILM-based diets had a 3–10% increase in egg laying percentage. There was higher profit margins when birds were fed diets containing 75% of HILM (~1.83 and 5.98 US$ per bird), which mirrored the return on investment estimated at 63.95% and 33.36% for the pullets (growers) and laying hen, respectively. Our findings demonstrate that diets with 75% HILM provided optimum growth performance, reduced feeding costs, increased weight gain and egg production as well as improved economic returns for commercial on-farm poultry production systems.Item Optimizing sunflower production through the use of GIS-based soil fertility management strategy(taylor & Francis, 2024-07-31) Nungulaa, Emmanuely Z.; Massaweb, Boniface J.; Chappac, Luciana R.; Nhundab, Daniel M.; Seleimand, Mahmoud F.; Alie , Nawab; Gitari, Harun I.this study aimed to use a GiS-based approach in producing soil fertility maps and utilize the spatial data on achieving site-specific management of major nutrients in Morogoro, Tanzania. Soil samples were collected in six mapping units and analyzed for chemical properties such as ph, cation exchange capacity and electrical conductivity. arcGiS 10.8 was used to produce nutrient variability maps of organic carbon, available p, total nitrogen and exchangeable K, ......Item Insect frass fertilizer as a regenerative input for improved biological nitrogen fixation and sustainable bush bean production(Frontiers, 2024-09-05) Chepkorir,Agnes; Beesigamukama, Dennis; Gitari, Harun I.; Chia, Shaphan Y.; Subramanian, Sevgan; Ekes, Sundayi; Abucheli, Birachi Eliud; Rubyogo, Jean Claude; Zahariadis, Theodore; Athanasiou, Gina; Zachariadi, Aikaterini; Zachariadis, Vasileios; Tenkouano, Abdou; Tanga, Chrysantus MBush bean (Phaseolus vulgaris L.) production is undermined by soil degradation and low biological nitrogen fixation (BNF) capacity. This study evaluated the effect of black soldier fly frass fertilizer (BSFFF) on bush bean growth, yield, nutrient uptake, BNF, and profitability, in comparison with commercial organic fertilizer (Phymyx, Phytomedia International Ltd., Kiambu, Kenya), synthetic fertilizer (NPK), and rhizobia inoculant (Biofix, MEA Fertilizers, Nairobi, Kenya). The organic fertilizers were applied at rates of 0, 15, 30, and 45 kg N ha−1 while the NPK was applied at 40 kg N ha−1, 46 kg P ha−1, and 60 kg K ha−1. The fertilizers were applied singly and in combination with rhizobia inoculant to determine the interactive effects on bush bean production. Results showed that beans grown using BSFFF were the tallest, with the broadest leaves, and the highest chlorophyll content. Plots treated with 45 kg N ha−1 BSFFF produced beans with more flowers (7 – 8%), pods (4 – 9%), and seeds (9 – 11%) compared to Phymyx and NPK treatments. The same treatment also produced beans with 6, 8, and 18% higher 100-seed weight, compared to NPK, Phymyx, and control treatments, respectively. Beans grown in soil amended with 30 kg N ha−1 of BSFFF had 3–14-fold higher effective root nodules, fixed 48%, 31%, and 91% more N compared to Phymyx, NPK, and rhizobia, respectively, and boosted N uptake (19 – 39%) compared to Phymyx and NPK treatments. Application of 45 kg N ha−1 of BSFFF increased bean seed yield by 43%, 72%, and 67% compared to the control, NPK and equivalent rate of Phymyx, respectively. The net income and gross margin achieved using BSFFF treatments were 73 – 239% and 118 – 184% higher than the values obtained under Phymyx treatments. Our findings demonstrate the high efficacy of BSFFF as a novel soil input and sustainable alternative for boosting BNF and improving bush bean productivity.Item Enhancing germination and seedling growth of barley using plasmaactivated water (PAW) with neutralized pH(taylor & Francis, 2024-07-31) Seleiman, Mahmoud F.; Ali, Nawab; Nungula, Emmanuely Z.; Gitari, Harun I.; Alhammad, Bushra A.; Battaglia, Martin l.achieving the highest seed germination and seedling growth rates is of paramount importance to maximize overall crop productivity. among different technologies aiming at increasing seed germination and early plant growth, cold atmospheric pressure plasma (Cap) and plasma-activated water (paW) are two of the most promising. however, Cap has been shown to decrease the ph of water, potentially constraining the utility of paW in applications involving ph-sensitive plants. here, we assessed the impact of magnesium addition to paW (Mg-paW), a potential mitigator of water acidity, on barley germination and growth compared to Cap technology without Mg (paW). although seed germination increased with both treatments compared to just Di water (control), the increase was higher when Mg-paW was added, increasing by 2.29 and 2.59 times on day 2 and day 3. application of Mg-paW also increased water absorption, seedling growth (both in terms of weight and length), concentrations of chlorophyll, carotenoids, total soluble protein and enzymatic activities compared to both the control and the paW treatment. the Mg-paW displayed a 1.8-fold higher total soluble protein level compared to paW alone. although both treatments reduced Malondialdehyde (MDa) content, a prominent stress marker in plants, Mg-paW application resulted in a 46% higher reduction in MDa content than paW alone. also, Mg-paW application increased superoxide dismutase (SoD) activity by 50%, and catalase (Cat) enzyme activity by 8% compared to paW alone. the implications of these discoveries extend to different agricultural applications, offering a promising avenue for improved early plant growth using Mg-paW technologies under neutral or near-to-neutral ph conditions.Item Castor Meal and Ground Hydrothermalized Phonolite Optimize Sweet Potato Nutrition, Yield, and Quality(MDPI, 2024-07-23) Parecido, Renan J.; Soratto, Rogério P.; Fernandes, Adalton M.; Blanes, Mayara C.; Fidelis, Luis G.; Gitari, Harun I.; Dutra, Sérgio G.To assess the effect of pure castor meal and a mixture of castor meal with ground hydrothermalized phonolite rock (CM+HP mixture) in providing nutrients, particularly N and K, and optimizing yield and quality of sweet potato, a field experiment was conducted using a randomized block design. Treatments were the absence and presence of synthetic N and K fertilizers (ammonium nitrate and KCl) combined with rates of organic fertilizers (1.2 and 2.4 Mg ha−1 of castor meal, 2.25 and 4.5 Mg ha−1 of CM+HP mixture, plus a treatment without organic fertilizers). The CM+HP mixture maintained adequate N and K status in plant leaves. Organic fertilizers increased the number of storage roots per plant and the sweetness of the storage roots, while synthetic fertilizers increased the storage root mean weight. Castor meal combined with synthetic fertilizers improved soil health (increased organic matter and enzyme activity in the soil). The combined application of synthetic fertilizerswith2.4Mgha−1 ofcastormealor4.5Mgha−1 of CM+HP mixture had the greatest benefit on storage root yield, with an average increase of 128% (10.9 Mg ha−1) on marketable storage root yield, and the nutrient removal compared with the sole application of organic fertilizersItem Sustainable fodder production in South Asia through silvopastoral systems(Current Science, 2024-05-25) Sow, Sumit; Ranjan,Shivani; Kumar, Navnit; Nilanjaya; Gitari, Harun; Daya, Parmeswar; Kumar, SanjaySilvopasture is a farming practice involving the integration of tree and livestock grazing operations on the same land. Intensive management of these systems enables them to generate short and long-term economic returns from forest products and forage. Silvopastoral systems have been considered to increase efficiency while reducing the environmental burden and extreme ranching/animal husbandry systems. Over the past few years, there has been a rapid accumulation of scientific evidence supporting the role of silvopasture in meeting the fundamental needs of not only humans but also the animal population in the era of climate change. In South Asian countries like India, the silvopastoral system can be a viable option to provide balanced food as well as shelter for the livestock. This review aims to provide a critical and systematic evaluation of the scientific literature about the effect of different silvopasture systems on the fodder production, environment and performance of livestock, especially in the context of South Asia. We conducted a search using PubMed, Scopus, Science Direct, Web of Science and Google Scholar to identify the key literature on the theme. A total of 98 manuscripts underwent a four-step PRISMA appraisal process, resulting in the final selection. This process resulted in a final sample of 56 articles, which were used to explore the potential for long-term improvement in fodder quality through expanding the silvopastoral system. One of the key conclusions is that by improving the social acceptability of these silvopastoral systems and also addressing the challenges, their economic and environmental sustainability can be further enhanced.