RP-Department of Agricultural Sciences and Technology

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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.
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.
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, Rebecca
Climate 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.
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.
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.
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.
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, ......
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 M
Bush 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.
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.
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 fertilizers
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, Sanjay
Silvopasture 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.
Bacillus Amyloliquefaciens D203 Ameliorates Rice Growth and Resistance to Rice Blast Disease
(Cogent Food & AgriCulture, 2024-06) Mirara, Francis; Dzidzienyo, Daniel Kwadjo; Mwangi, Maina
This study evaluated the effects of Bacillus amyloliquefaciens D203 encapsulated in alginate-bentonite coating enriched with titanium nanoparticles on rice germination and Magnaporthe oryzae infection. Seed coating was achieved using the ionic gelation/extrusion method with modifications. The study investigated various concentrations of strain D203 on biomass and bacterial release from the beads, along with its influence on detached leaves. Results showed that treatment with a strain D203 cell suspension (2 × 107 CFU/ml) significantly enhanced root and shoot lengths, despite a slightly lower germination rate (90%) compared to the control. Treatment with a concentration of 1 × 107 proved to be optimum for growth because it maintained germination at 100% and boosted biomass growth of shoot and root by 49.57% and 16.44%, respectively. Colonization by strain D203, explored through seed coating and subsequent resuspension from roots and media, peaked in roots, indicating preferential root zone inhabitation. In vitro studies demonstrated strain D203’s efficacy against M. oryzae at 21 and 40 days, with the 1 × 107 CFU/ml spray significantly reducing disease symptoms. Strain D203 exhibited a preventive effect, especially in early growth stages. The encapsulated form of strain D203 had a control effect comparable to 40% Hexaconazole but less effective than 75% Tricyclazole. Uncoated and encapsulated B. amyloliquefaciens treatments significantly improved sterile rice plant growth over 21 days, with the encapsulated bead treatment surpassing both controls and free cell treatments by days 14 and 21, despite slower initial growth. Encapsulation presents a promising alternative, potentially matching the effectiveness of chemical fungicides, emphasizing the importance of environmentally friendly alternatives in sustainable disease management strategies.
Artiﬁcial Intelligence for Maximizing Agricultural Input Use Efﬁciency: Exploring Nutrient, Water and Weed Management Strategies
(Tech Science Press, 2024-05-30) Sow, Sumit; Ranjan, Shivani; Seleiman, Mahmoud F.; Alkharabsheh, Hiba M.; Kumar, Mukesh; Kumar, Navnit; Padhan, Smruti Ranjan; Roy, Dhirendra Kumar; Nath, Dibyajyoti; Gitari, Harun; Wasonga, Daniel O.
Agriculture plays a crucial role in the economy, and there is an increasing global emphasis on automating agricultural processes. With the tremendous increase in population, the demand for food and employment has also increased signiﬁcantly. Agricultural methods traditionally used to meet these requirements are no longer adequate, requiring solutions to issues such as excessive herbicide use and the use of chemical fertilizers. Integration of technologies such as the Internet of Things, wireless communication, machine learning, artiﬁcial intelligence (AI), and deep learning shows promise in addressing these challenges. However, there is a lack of comprehensive documentation on the application and potential of AI in improving agricultural input efﬁciency. To address this gap, a desk research approach was used by utilizing peer-reviewed electronic databases like PubMed, Scopus, Google Scholar, Web of Science, and Science Direct for relevant articles. Out of 327 initially identiﬁed articles, 180 were deemed pertinent, focusing primarily on AI’s potential in enhancing yield through better management of nutrients, water, and weeds. Taking into account research ﬁndings worldwide, we found that AI technologies could assist farmers by providing recommendations on the optimal nutrients to enhance soil quality and determine the best time for irrigation or herbicide application. The present status of AI-driven automation in agriculture holds signiﬁcant promise for optimizing agricultural input utilization and reducing resource waste, particularly in the context of three pillars of crop management, i.e., nutrient, irrigation, and weed management.
Sustainable fodder production in South Asia through silvopastoral systems
(Indian Academy of Sciences, 2024-05-25) Sow, Sumit; Ranjan, Shivani; Kumar, Navnit; Nilanjaya; Gitari, Harun; Dayal, Parmeswar; Kumar, Sanjay
Silvopasture 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
A Review on Nitrogen Flows and Obstacles to Sustainable Nitrogen Management within the Lake Victoria Basin, East Africa
(MDPI, 2024-05) Masso, Cargele; Gweyi-Onyango, Joseph; Luoga, Hilda Pius; Yemefack, Martin; Vanlauwe, Bernard
The Lake Victoria Basin (LVB) is located in the upper reaches of the Nile River Basin and is shared by five East-African countries. The population in the catchment is growing rapidly and the lake is facing several environmental problems. During the past few decades, numerous efforts have been made across the five countries, with the coordination of the Lake Victoria Basin Commission (LVBC) to reduce the loading of reactive nitrogen (Nr) into the lake and Lake Watershed. However, most of the measures envisaged to ensure long-term sustainable N management are not as easily adopted as planned. This paper reports on a review study on N flows and obstacles in achieving sustainable N management in the LVB, with the objectives of improving the understanding of the N cycle and examining the N management practices and policies that can help reduce the loss of Nr in the region. The scientific literature related to a range of N flows, N management obstacles, and options to overcome obstacles has been analyzed using N prospects developed at the global level for their potential applicability across the LVB. The study showed that an unbalanced use of N input is a serious threat to agricultural productivity leading to extreme soil N mining and degradation, with the majority of LVB farms operating within negative N balances and above the safe operating boundary for N in production systems. From the projections in N input as recommended by various stakeholders, there would likely be changes in both current yield and N use efficiency (NUE) values; however, most small-scale farmers will continue to experience low yields, which remains a challenge for food security in the area. These results suggest that scientists as well as those involved in decisionmaking and policymaking processes should formulate new targets for fertilizer increment to reduce the yield gap for sustainability, focusing on more integrated soil fertility as a package for nutrient management in cropping systems.
Sustainable fodder production in South Asia through silvopastoral systems
(Current science, 2024-05) Sow, Sumit; Ranjan, Shivani; Kumar, Navnit; Nilanjaya; Gitari, Harun; Dayal, Parmeswar; Kumar, Sanjay
Silvopasture 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.
Conservation agriculture and weed management effects on weed community and crop productivity of a rice-maize rotation
(Heliyon, 2024-05) Sahoo, Subhra; Seleiman, Mahmoud F.; Roy, Dhirendra Kumar; Ranjan, Shivani; Sow, Sumit; Jat, Raj Kumar; Alhammad, Bushra A.; Gitari, Harun
In recent years, an increase in weed infestation, which is adversely affecting crop growth and productivity has been a major challenge facing the farmers of South Asia. The adoption of a permanent bed in combination with residue retention-based crop management practices may reduce weed abundance and increase crop productivity. In a two-year field study, we evaluated the responses of different organic weed management practices with contrasting tillage and residue (R) management strategies to weed dynamics and crop productivity under rice-maize rotation. The main plot treatments consisted of zero-tillage direct seeded rice and zero-tillage maize (ZTR fb ZTM); ZTDSR and maize both on permanent raised beds with residue (PBDSR+R fb PBDSM+R); PBDSR and PBM without residue (PBDSR-R fb PBDSM-R) and conventional tillage puddled transplanted rice and conventional tillage maize (CTR fb CTM). The subplots comprised unweeded control; vermicompost mulch; P- enriched vermicompost mulch; live mulch with Sesbania spp. in rice and Pisum sativum in maize and weed-free. Total weed density and biomass in rice and maize at 30 days after sowing (DAS) were minimum for PBDSR+R fb PBDSM+R compared to remaining tillage and residue management practices in both years. Apart from weed-free treatment, the highest weed control index was found with live mulch. Yield of rice and maize were found higher in permanent beds along with residue retention-based practices. In rice, the weed-free treatment showed the highest grain yield and live mulch reported 9.8 and 6.8% higher grain yield than vermicompost mulch and P-enriched vermicompost mulch respectively. Our study shows that conservation agriculture practices under rice-maize rotation is one of the ways to reduce weed density and improve crop productivity in South Asia and other similar agro-ecologies.
Maize-soybeans intercropping increases nutrient uptake, crop yield and modifies soil physio-chemical characteristics and enzymatic activities in a subtropical humid region based in Southwest China
(Research square, 2023-12) Nasar, Jamal; Ahmad, Munir; Gitari, Harun; Tang, Li; Chen, Yuan; Zhou, Xun-Bo
In China, the high use of nitrogen fertilization for agricultural production and intensive mono-cropping systems have adversely affected the agricultural ecosystem and environment. Therefore, to improve the sustainable agricultural production system, farming systems need to be adjusted within the country. Consequently, a two-year (2021–2022) field experiment was conducted on the maize/soybean intercropping practices with/without nitrogen (N) fertilization (i.e., N0; 0 N kg ha− 1 and N1; 225 N kg ha− 1) to know whether such cropping system can improve the nutrients uptake and crop yields, soil physio-chemical properties, and soil enzymes, which ultimately results in enhanced crop yield. The results revealed that maize intercropping treatments (i.e., N0MI and N1MI) had higher crop yield, biomass dry matter, and 1000-grain weight of maize than mono-cropping treatments (N0MM, and N1MM). Nonetheless, these parameters were optimized in N1MI treatments in both years. For instance, N1MI produced the maximum grain yield (10105 and 11705 kg ha− 1), biomass dry matter (13893 and 14093 kg ha− 1), and 1000-grain weight (420. and 449 g) of maize in the year 2021 and 2022, respectively. Conversely, soybean intercropping treatments (i.e., N0SI and N1SI) reduced such yield parameters for soybean. Also, the land equivalent ratio (LER) and land equivalent ratio for N fertilization (LERN) values were always greater than 1, showing the intercropping system's benefits in terms of yield and improved resource usage. Moreover, maize intercropping treatments (i.e., N0MI and N1MI) and soybean intercropping treatments (i.e., N0SI and N1SI) significantly (p < 0.05) enhanced the nutrient uptake (i.e., N, Fe, P, K, Ca, and Zn) of maize and soybean, however, these nutrients uptakes were more prominent in N1MI and N1SI treatments of maize and soybean, respectively in both years (2021 and 2022) compared with their mono-cropping treatments. Similarly, maize-soybean intercropping treatments (i.e., N0MSI and N1MSI) significantly (p < 0.05) improved the soil-based N, K, P, NH4, NO3, and soil organic matter, but, reduced the soil pH. Such maize-soybean intercropping treatments also improved the soil enzymatic activities such as protease (PT), sucrose (SC), acid phosphatase (AP), urease (UE), and catalase (CT) activities. This indicates that maize-soybean intercropping could potentially contribute to higher and better crop yield, enhanced plant nutrient uptake, improved soil nutrient pool, physio-chemical characteristics, and related soil enzymatic activities. Thus, preferring intercropping to mono-cropping could be a preferable choice for ecological viable agricultural development.
Morphological, Pedological and Chemical Characterization and Classiﬁcation of Soils in Morogoro District, Tanzania
(National Academy of Agricultural Sciences, 2023-12) Nungula, Emmanuely Z.; Mugwe, Jayne; Massawe, Boniface H. J.; Gitari, Harun I.
Abstract This study was carried out in Morogoro district, Tanzania to characterize and classify soils using USDA Soil Taxonomy and World Reference Base (WRB) for Soil classiﬁcation methods. The site characteristics were identiﬁed during the reconnaissance survey for the determination of sampling units. Six soil proﬁle pits namely TUG-P1, TUG-P2, TUG-P3, TUG-P4, TUG-P5, and TUG-P6 were excavated, described, and sampled for laboratory physico-chemical analysis. Topsoil bulky densities were determined and ranged from 1.23 to 1.37 g cm-3. The surface soil pH ranged from moderately acidic to slightly acidic (5.69–6.58) and subsoil from strongly acidic to neutral (4.72–7.30). Soil organic carbon (OC) was low for both top (2.93–4.79 g kg-1) and subsoil (2.34–3.51 g kg-1). Total nitrogen was medium (2–4 g kg-1 for the topsoil and 2–3 g kg-1 for the subsoil. Available P rated low with the top soil having 4.81–6.22 cmol kg-1 and subsoil recording 3.12–6.14 cmol kg-1. The cation exchange capacity for topsoil ranged from 5.31 to 8.10 cmol kg-1 whereas for subsoil it was 4.91–8.10 cmol kg-1. Using the USDA Soil Taxonomy, soils were classiﬁed as Rhodic Siderudox (TUGP1), Typic Sombrustert (TUG- P2), Typic Eutrustolls (TUG- P3), Psamm Haplustepts (TUG- P4), Typic siderustepts (TUGP5) and Typic Siderudox (TUG- P6). Under WRB, soil was classiﬁed as Rhodic Umbric Ferralsols (Eutric, Arenic) (TUGP1), Haplic Vertsols (Aric, Orchric) (TUG- P2), Rhodic Eutric Cambisols (Arenic, Aric) (TUG- P3), Haplic Arenosols (Aric, Orchric) (TUG- P4), Rhodic Umbric Ferralsols (Eutric, Arenic) (TUG- P5) and Umbric Ferralsols (Eutric, Arenic) (TUG- P6). Soils showed a high level of weathering of parent material with deep depth, and ﬁne texture dominated by sesquioxides and kaolinitic clays. To sustain yields, the soil’s nutrient management ought to involve the use of integrated approaches such as the application of inorganic (synthetic fertilizer) and organic nutrient inputs.
Impact of Specific Leaf Extracts on Soil pH and Beta-Carotene in Amaranthus in Kiambu County, Kenya
(AJAHR, 2024-04) Njeru, N; Wa Githendu, Mukiri; Murungi, J.
Amaranthus (Amaranthus spp.) leaves are a good source of nutrients including vitamins antioxidants and dietary minerals including calcium, iron, and potassium. Soil pH is a very important chemical property of the soil, as it dictates the availability of plant nutrients. Acidic soils reduce availability of plant nutrients and hinder growth. This is corrected by adding lime which is expensive, does not add nutrients and requires re-application. The objective of this study was to evaluate the effects of leaf extracts from selected tree leaves on soil acidity and beta-carotene levels of amaranthus. Plant leaves that were tested were Turril (Vitex keniensis) Mexican sunflower (Tithonia diversifolia) and Indian nettle (Plectranthus barbatus). The experiment setup was in a 2 x 7 factorial arrangement in a randomized complete block design(RCBDreplicated three timesThe treatments were; the three leaves extracts, lime, farm yard manure, inorganic fertilizer and control.. Leaves were dried,ground and soaked in distilledwater for sixty days as pH was monitored and the resulting extract was added to soil for amanthus grown with plant extracts. Data on plant height, leaf area, number of leaves, fresh weight and dry weight and levels of beta carotene levels were collected. AOAC method was used for analysis of beta carotene. All data was subjected to analysis of variance (ANOVA) at 5% level of significance using SAS and least significant difference (LSD) for means separation. The results showed that leaf extracts significantly reduced soil acidity to above (6) while inorganic fertilizer increased the acidity (pH5.9) to (5.3) on all growing conditions while humus increased acidity during rainy and irrigation conditions. On beta carotene levels, Farmyard Manure had the highest levels(51.1µg) followed by the leaf extracts with extract 3-Plectras barbatus having higher levels. Control had the lowest levels of beta carotene followed by inorganic fertilizer and lime.These results suggest that farmers should be encouraged to grow vegetables using farmyard manure and leaf extracts to increase antioxidant levels and reduce soil acidity.They should also be encouraged to grow more of trees and shrubs studied to increase forest cover.

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