Uganda Journal of Agricultural Sciences 2021-03-29T10:26:17+00:00 Dr Yona Baguma Open Journal Systems <p>The Journal publishes &nbsp;peer reviewed papers &nbsp;with the aim of sharing new developments in the agricultural and environmental sciences&nbsp; which include forestry, fisheries, livestock, crops, environment, biotechnology, agricultural economics, agricultural engineering.</p> <p>The readership of the Journal include students, researchers, extension workers, policy makers, academia ,investors and entrepreneurs.</p> Effect of Soaking Treatment on Germination of Hard Coated Tropical Forest Tree Seeds 2021-03-17T15:22:12+00:00 Juventine Boaz Odoi David Mugeni Robert Kiiza Betty Apolot Samson Gwali <p>Seed germination and seedling growth performance of <em>Maesopsis eminii</em> and <em>Terminalia catappa</em> under different water soaking treatments were evaluated for 120 days under nursery conditions. A total of 1400 seeds were pre-treated with hot (95oC) and cold water (ambient temperature) by soaking for 12, 24 and 48 hours with a control of no soaking. The seeds were sown directly into polythene pots filled with uniform growth medium (top forest soil, sand and clay soil<br>mixed in a ratio of 5:3:2) to avoid disturbance of the root system after germination. The seeds were sown in a randomized block design with seven treatments and three replicates. Data were analysed using ANOVA in GenStat v18. Results indicated that soaking enhanced seed germination. Soaking of seeds in cold water for 12 hours resulted into higher germination (90% for <em>Terminalia catappa</em> and 85% for <em>Maesopsis eminii</em>) than the control (48%). Soaking period and water temperature significantly influenced seedling vigour (F value = 0.962; p = 0.038). Soaking seeds in cold water for 24 hours enhanced <em>Maesopsis eminii</em> seedling growth by 8.0 cm <em>Terminalia catappa</em> seedlings by 7.4 cm. Seed dormancy, germination percentage and growth performance in hard coated seeds such as <em>Maesopsis emini</em>i and <em>Terminalia catapp</em>a can be broken by soaking in cold water for 12-24 hours. Pre-germination treatments significantly influences the germination and seedling growth.</p> <p><br><strong>Keywords:</strong> <em>Maesopsis eminii, Terminalia catappa</em>, seeds, pre-germination, soaking.</p> 2021-03-17T15:19:30+00:00 Copyright (c) 2019 Uganda Journal of Agricultural Sciences Stock Assessment of Lates niloticus in Upper Victoria Nile and its Impact on Uganda’s Economy 2021-03-17T15:22:13+00:00 Samuel Bassa Albert Getabu Erick Ogello Anthony Taabu Munyaho Dickson Oteino Owiti Herbert Nakiyende Laban Musinguzi John Stephen Balirwa Joseph Nyaundi Kiyuka Winnie Nkalubo <p>This study investigated the growth, mortality, recruitment, and catch estimates of Nile perch, <em>Lates niloticus</em> (Linnaeus, 1758), in Upper Victoria Nile, basing on total catches and length-frequency data collected between 2008 and 2018. The asymptotic length (L∞) had a value of 93.45 cm TL, growth curvature (K) was 0.446 year-1, total mortality (Z) was 1.85year-1, natural mortality (M) was 0.79 year-1, fishing mortality (F) was 1.09 year-1, exploitation rate (E) was 0.59 and growth performance index(ᴓ) of (L∞) was 3.604. There were two peaks recruitment period, a minor one in March and a major one in August. These respectively accounted for 12.8 and 26.3 percent of the total catch. The optimum sustainable yield (<em>E</em><sub>0.5</sub>), maximum sustainable yield (<em>E</em><sub>max</sub>) and, economic yield (<em>E</em><sub>0.1</sub>) was 0.278, 0.421 and 0.355 respectively. The findings suggest that there is a decline in the population of Lates niloticus in Upper Victoria Nile. Therefore, strict management of the fishery by adhering to the recommended slot size of 50-85 cm TL and curtailing use of illegal gears is needed. This will be possible through enforcement of regulations, monitoring, control and surveillance in order to ensure sustainability of the Nile perch fishery and ecosystem restoration in the Upper Victoria<br>Nile.<br><strong>Keywords:</strong> <em>Lates niloticus</em>; Catch rates; Growth parameters, Upper Victoria Nile.</p> 2021-03-17T14:49:58+00:00 Copyright (c) 2019 Uganda Journal of Agricultural Sciences Effect of Digestate from Rubber Processing Effluent on Soil Properties 2021-03-29T10:11:54+00:00 Muniratu Maliki Ikhazuagbe Hilary Ifijen Mulu Emmanuel Khan <p>Anaerobic digestion of rubber processing effluent (RPE) was conducted at 1:1 Effluent to Inoculums ratio to obtain biogas at a 40–day retention time. The physicochemical properties of the RPE were determined before and after anaerobic digestion. Digestate obtained thereof was used as soil amendment to investigate its bio-fertility potential. To study the effects, three kilograms (3Kg) of soil samples were separately treated with 0, 200, 400, 600 of the digested RPE. The effluent applied were thoroughly mixed with the soil, watered regularly and left for eight weeks for adequate mineralisation and equilibration. The soil physicochemical properties were determined before and after the amendment. The results from the amended soils showed that application of the digestate enhanced soil quality (as soil organic carbon, N, P, K, Ca, Na and % base saturation were significantly higher than in the control). However, the soil pH remained in the acidic region and the soil exchangeable acidity reduced.</p> <p><br><strong>Keywords:</strong> Digestate, soil properties, biogas, RPE.</p> 2021-03-17T14:49:00+00:00 Copyright (c) 2019 Uganda Journal of Agricultural Sciences Diversity and Abundance of Zooplankton in River Aswa in Uganda 2021-03-17T15:22:15+00:00 Vincent Kiggundu Samuel Vivian Mataagi Lucas Mwebaza Ndawula William Okello <p>Zooplankton community constitutes one of the keystone organisms that are crucial in understanding aquatic ecosystem responses to environmental distresses. The objective of this study was to contribute to the understanding of zooplankton ecological conservation status and assessment of potential impacts of the proposed Hydropower plant on the zooplankton community in River Aswa, Nwoya District, in Uganda. Baseline information on aquatic micro-invertebrate diversity, abundance and distribution along the affected river section was generated. Two copepods and four species of rotifers were recorded. The Intake site had the highest diversity (six species) while Powerhouse had<br>four species. Of the species encountered, <em>Keratella tropica</em> registered the highest abundance—1,025 and 732 individuals m-2 at the Powerhouse and Intake sites, respectively. Total zooplankton densities were comparable with Intake (2,773 individuals m-2) and Powerhouse (2,311 individuals m-2). The zooplankton taxa do not appear in the IUCN Red List in the Catalogue of Life. Therefore, the proposed construction of a hydropower plant may not pose zooplankton conservation problems.</p> <p><strong>Keywords:</strong> Biodiversity, Zooplankton, invertebrates, hydropower, River Aswa.</p> 2021-03-17T14:44:23+00:00 Copyright (c) 2019 Uganda Journal of Agricultural Sciences Occurrence and distribution of Organochlorine Pesticide Residues in Water and Sediments of Earthen Fish Ponds in South Western Kenya 2021-03-29T10:26:17+00:00 Joseph Kiyuka Nyaundi Albert Getabu James Onchieku Zachary Kinaro Samuel Bassa Chrisphine Nyamweya Hilda Nyaboke Zachary Getenga <p>Persistent organochlorine residues in the environment are a threat to ecological health of aquatic organisms and pose a health risk to both animals and human consumers. Organochlorine pesticides were determined in water and sediments collected during wet and dry season from selected riverine and earthen fish pond sites in high altitude catchment areas within Kuja River (Kenya) between August 2016–May, 2017. Analysis of DDT and metabolites, Hexachlorocyclohexanes (HCHs) isomers and cyclodienes using a gas chromatograph (GC), and electron capture detector (ECD), confirmed using GC - Mass Spectrometry (MS). Mean (± Standard error) results of DDTs, cyclodienes and HCHs in pond waters were:- below detection level (BDL) to 0.27±0.03µg/L, BDL to 0.11±0.00µg/L, and 4.39±1.01µg/L respectively; and BDL to 0.23±0.01µg/L, 1.20±0.005µg/L, and 1.71±0.02µg/L in river water respectively. Sediment mean OCPs contents were significantly (p&lt;0.05) higher for Dieldrin (3.043±0.43µg/kg), Endrin (2.56±0.460µg/kg), Heptachlor (3.61±0.02µg/kg) DDT (2.97±1.32µg/kg), Endosulfan (6.31.27±1.051µg/kg), Methoxychlor (2.15±1.641µg/kg) and Lindane (2.96±1.32µg/kg), respectively. A longitudinal spatial distribution pattern was noted for both water and sediment OCPs contents, demonstrating that cyclodienes are predominant contaminants in point and non-point sources in water courses. The study recommends continuous monitoring of OCPs in upstream catchment areas for informed management and policy decisions on pesticide use.</p> <p><br><strong>Keywords:</strong> Kuja-Migori River; Organic contaminants; Organochlorine Pesticide.</p> 2021-03-17T14:42:26+00:00 Copyright (c) 2019 Uganda Journal of Agricultural Sciences