Botswana Journal of Agriculture and Applied Sciences https://bojaas.buan.ac.bw/index.php/jaas <p><strong>AIMS AND SCOPE</strong></p> <p>The journal is published in English twice in a year. It publishes original research in all areas of agriculture and its related applied sciences. The Journal accepts Review papers which attempts to bring together state of the art in agriculture in Botswana and in the region. These should be incisive, analytical and have a provocative edge to stimulate discussion and chart the way forward for agriculture in Botswana. Current and global hot topics with relevance to agriculture productivity and farmer’s livelihood in Botswana are encouraged. Short communication reporting on interesting data of early stage research or limited experiment could be submitted.</p> <p><strong>Proposals for Conference Issues, Special Issues or Sponsored Issues</strong></p> <p>BOJAAS considers special issues for the next calendar year in the first quarter of the previous calendar year.</p> <p>Proposals for Conference Issues, Special Issues or Sponsored Issues should be directed to the Editor: Prof. Sello Alfred Likuku via email <a href="mailto:alikuku@buan.ac.bw">alikuku@buan.ac.bw</a> / <a href="mailto:likuku_as@yahoo.com">likuku_as@yahoo.com</a> or the editorial submission system <a href="https://bojaas.buan.ac.bw">https://bojaas.buan.ac.bw</a> .</p> <p>A one-two page rationale for the special issue, outlining the gap in academic knowledge and practice it is hoped to address should include be included. For these to be considered they should also include a one page CV of any proposed editors and an outline of the conference or symposium arrangements proposed.</p> <p>BOJAAS reserves the right to vary these requirements as the editor deems appropriate.</p> Botswana University of Agriculture and Natural Resources en-US Botswana Journal of Agriculture and Applied Sciences 1815-5774 Take me to the River along the African drought corridor: Adapting to climate change https://bojaas.buan.ac.bw/index.php/jaas/article/view/77 <p>This paper brings together a wide range of concepts from climate change predictions, palaeoecology, wildlife ecology and sustainable livelihoods in order to prioritise adaptive management measures that are necessary for the conservation of the African megafauna. Climate change predictions emphasise the severe aridity that will surge into southern Africa later this century and must be contrasted with the relatively wetter conditions in eastern Africa. The evolution of African mammals and their adaptive responses to past episodes of climate change is explained by reference to range shifts and movements along Balinsky’s (1962) ‘drought corridor’ that extends from SW Africa northeastwards to Somalia and then westwards across the Saharan-Sahelian zone. The drought corridor today could potentially extend from Kenya southwestward through to Botswana/South Africa and Namibia, via connectivity corridors linking existing wildlife areas, forming the Kalahari-Rift Valley Transfrontier Conservation Landscape (KALARIVA TFCL). The most promising route along the drought corridor links the Chobe – Linyanti – Kwando river systems of Botswana/Namibia with Luangwa Valley in Northern Zambia, along the Zambezi River via Lake Kariba (Matsudonna and Mana Pools) in Zimbabwe. Malawi poses an absolute barrier to such connectivity and by the turn of this Century runs the risk of confining the area to the south almost entirely to the SW arid adapted fauna and that to the north to water dependent ungulates such as elephants, buffalo and zebra. The key movement corridors are identified in a bid to extend the spatial and temporal scale of conservation planning in order to adapt effectively to climate change. The importance of ‘co-existence’ between wildlife and people is emphasised together with the need for local communities to benefit from sharing the KALARIVA TFCL with African wildlife, via new models of conservation financing and management that reward rural African communities for being the true custodians of the African megafauna.</p> Jeremy Simon Perkins ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 60 71 10.37106/bojaas.2020.77 Classification of riparian woody plant communities along the Thamalakane River in northwestern Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/85 <p>There is still paucity of information on the species composition of woody species along the Thamalakane River, northern Botswana, which may limit efforts aimed at conserving riparian woodland species. The current study was aimed at classifying the vegetation, and determining the species composition and diversity of the riparian woodland plant communities along the Thamalakane River. It was hypothesized that there will be no different woodland communities along the Thamalakane River. The 71 sampling plots measured 1000m<sup>2 </sup>(20m × 50m). In each plot,the percentage cover for each species was estimated following the Braun-Blanquet scale. Different woodland communities were determined through Hierarchical Cluster Analysis followed by Indicator Species Analysis. Multi-Response Permutation Procedures (MRPPs) were used to determine whether or not there was a significant separation between the groups. The Kruskal-Wallis test was used to statistically compare the diversity between woodland communities. Five major woodland communities were identified along the Thamalakane River, namely <em>Vachellia tortilis-Gardenia volkensii, Combretum imberbe-Gymnosporia senegalensis, Philenoptera violacea-Garcinia livingstonei, Dichrostachys cinerea-Flueggea virosa </em>and <em>Croton megalobotrys</em>-<em>Colophospermum mopane. </em>There was significant (<em>p </em>&lt;0.05) separation between the plant groups. Species diversity was highest in <em>Dichrostachys cinerea-Flueggea virosa</em> community and lowest in <em>Vachellia tortilis-Gardenia volkensii </em>community. The distribution of woodland species in along Thamalakane river could be influenced by human disturbance, which may override abiotic environmental conditions such as flooding in influencing the composition and distribution of plant species. This calls for proper management initiatives of the riparian vegetation in the study area. Such initiatives may include establishment of exclosures to promote the germination and propagation of the woodland species. Other strategies may include education and awareness creation of the local communities to promote their co-existence with the riparian vegetation.</p> G. Tsheboeng D. Teketay M. Murray-Hudson K. Kashe M. Mmusi J. Madome ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 47 59 10.37106/bojaas.2020.85 Effects of enclosure management and rangeland sites on chemical composition of herbaceous species in south central Ethiopia https://bojaas.buan.ac.bw/index.php/jaas/article/view/19 <p>This study was conducted in Adami-Tullu Jido-Kombolcha and Arsi Negelle districts, south central Ethiopia. The objectives of the study were to evaluate the interactive effects of grazing management systems and rangeland sites on dry-matter production and chemical composition of herbaceous plants in south central Ethiopia. Data were analyzed using GLM procedure in SPSS 16.0 version, which was used for mean comparisons using post-hoc t-test that can be employed to compare mean differences for enclosure and open-grazed areas. To test the effects of management systems and altitudinal variation on dry-matter production and chemical composition of herbaceous species, mixed model analysis was employed using sample site as a random variable while grazing management systems and altitude were fixed variables. A total of 28 herbaceous species were identified. Of the identified herbaceous species, 20 species were grasses, 2 species were legumes while 6 species were forbs. Among the recorded grass species, some were highly desirable, while others were in the categories of intermediate in terms of desirability and less desirable. We identified the dominant and common grass species that included: <em>Arstida adscensionis, Cenchrus ciliarus, Chloris gayana, Chloris roxburghiana, Bothriochloa insculpta, Eragrostis papposa, Heteropogon contorus, Panicum maximum, Indigofer spinosa, Tephrosia pumila, Sporobolus pyrmidalis, Themeda triandra, B. nigropedata, </em><em>Ocimum basilicum, </em><em>Amaranthus dubis, Tribulos terrestris</em> and <em>Achyrantes </em><em>aspera</em>. The chemical composition of herbaceous plants were analyzed for DM, CP, NDF, ADF, ADL and Ash comparing two grazing management systems and three rangeland sites as patch mosaic units. The results of the present analysis showed that the average CP content in the open-grazed areas was significantly (<em>P</em>&lt;0.05) higher than that of the enclosed areas. The upper and middle rangeland sites displayed significantly (<em>P</em>&lt;0.05) higher CP content for the open-grazed areas than the enclosure management across the study areas. The present findings suggest that the DM, NDF, ADF, ADL and Ash contents of herbaceous species was significantly (<em>P</em>&lt;0.05) lower in the open-grazed areas than in the enclosure management.</p> Mulugeta Gudisa Ayana Angassa Abdeta Aster Abebe Kenea Feyisa Alemayehu Mengistu ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 38 46 10.37106/bojaas.2020.19 Role of farmer’s indigenous knowledge for adaptation and mitigation to Climate Change in Kgalagadi-North District, Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/33 <p>This paper presents perception of farmers in terms of adaptation and mitigation to climate change in Kgalagadi-North District. The study used qualitative survey method and results are derived from purposively selected interviews using semi-structured questionnaire. The research focused on participants who were aged 50 years and above. Data were summarized and analysed qualitatively using descriptive statistics. Farmers’ perceptions showed that frequent wildfire was major cause of climate change. Farmers further mentioned that they were affected by irregular rainfall, increased temperature and recurrent droughts. The findings confirmed that milk production and number of calves per cows were in declining trend over the last 30 years. The results showed increased trends in donkeys’ population signifying importance of donkeys in farmer’s herd as adaptation strategy. The results revealed that livestock diversification, making use of migratory approach in search of pasture and water, and sale of livestock before onset of drought are key adaptation strategies developed by farmers. The results also displayed that farmers mainly used to practice different strategies such as saving food and seeds, use of drought tolerant crops, diversifying crop varieties and changing of planting dates to overcome the irregularity of rainfall. Results revealed that farmers mostly used to pray for rains and involve in environmental management for adaptation and mitigating. It seems that adaptation and mitigation measures employed by farmers helped them to enhance resilience and reduce vulnerability. We suggest that farmers’ experience for adaptation and mitigation to climate change plays a crucial role in scientific research and sustainable development.</p> Summer Mabula Ayana Angassa Abdeta ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 28 37 10.37106/bojaas.2020.33 A Review of piggery manure management: generally, across western, Asian and African countries https://bojaas.buan.ac.bw/index.php/jaas/article/view/17 <p>The aim of this paper was to review the piggery waste management aspects in several countries of the world. Intensive livestock production produces significant quantities of waste that must be managed to protect water, air, and crop quality. The high demand of modern animal production has been influenced by the rapid growing populations as a result of rapid economic growth and increase in community living standards which is associated with the accelerated generation rate of solid waste causing a serious worldwide challenge. Piggery waste is said to be one of the most important causative agents of environmental pollution in most parts of the world. A growing pig population is unavoidable because it is a convenient source of protein to the growing human population and at the same time this means increasing piggery waste. Animal manure can provide nutrients for crops and fish production and input for biogas production, but if not managed, then this can also have a negative impact on the environment. Nevertheless, there are few countries who are considering legislation in relation to manure management.</p> James Buttie Machete Ricks G Chabo ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 17 27 10.37106/bojaas.2020.17 Evaluation of gastrointestinal nematode infection and levels of anthelmintic resistance in small-holder goat flocks from three villages around Gaborone, Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/23 <p>This study aimed to investigate: 1) gastrointestinal nematode (GIN) infection in goat flocks, and 2) efficacy of ivermectin treatment in three villages around Gaborone, Botswana. A 100 goats randomly selected from 10 smallholder flocks from Modipane (n = 40), Kopong (n= 30), and Gakuto (n= 30) were evaluated for faecal egg count (FEC), body condition (BCS), FAMACHA<sup>®</sup> scores (FS), and packed cell volume (PCV) and marked for subsequent identification. Thereafter, all adult goats in participating flocks were treated with ivermectin at 5 mg/kg bodyweight. Seventy-four goats that were FEC positive were re-sampled 11 to 14 days later for a faecal egg count reduction test (FECRT). Mean FEC were in the range 67.5±14.2 to 380±50 (Mean ± SEM) eggs per gram (EPG) but varied significantly at 95% confidence level, between villages and between flocks in the same village. In all but one Modipane flock, the BCS was &gt;3 and acceptable. Similarly, only one flock from Kopong had a FS tending to anaemia. All flocks had a mean PCV within the normal range. Notably, the flock with the highest FS had the lowest PCV. Ivermectin was effective except in one flock whose FEC increased post treatment suggesting anthelmintic resistance. In conclusion, GIN infection is common in smallholder goat flocks in Botswana, although there are significant differences in FEC both between villages and between flocks in the same village. Although possible resistance was observed in one flock, the FECRT indicates that ivermectin is still effective in the majority of the flocks.</p> Solomon Stephen Ramabu Tove Johansson Jonas Johansson Wensman Johan Höglund ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 1 6 10.37106/bojaas.2020.23 COMPARATIVE NUTRITIVE VALUE OF AN INVASIVE EXOTIC PLANT SPECIES, Prosopis glandulosa TORR. var. glandulosa, AND FIVE INDIGENOUS PLANT SPECIES COMMONLY BROWSED BY SMALL STOCK IN THE BORAVAST AREA, SOUTH-WESTERN BOTSWANA https://bojaas.buan.ac.bw/index.php/jaas/article/view/25 <p>Nutritive value of an invasive exotic plant species, Prosopis glandulosa Torr. var. glandulosa, and five indigenous plant species commonly browsed by livestock in Bokspits, Rapplespan, Vaalhoek and Struizendam (BORAVAST), southwest Botswana, was determined and compared. These five indigenous plant species were Vachellia hebeclada (DC.) Kyal. &amp; Boatwr. subsp. hebeclada, Vachellia erioloba (E. Mey.) P.J.H. Hurter, Senegalia mellifera (Vahl) Seigler &amp; Ebinger subsp. detinens (Burch.) Kyal. &amp; Boatwr., Boscia albitrunca (Burch.) Gilg &amp; Gilg-Ben. var. albitrunca and Rhigozum trichotomum Burch. The levels of Crude Protein (CP), Phosphorus (P), Calcium (C), Magnesium (Mg), Sodium (Na) and Potassium (K) were determined for the plants foliage and pods (where available). All plant species had a CP value higher than the recommended daily intake. There are however multiple mineral deficiencies in the plant species analysed. Nutritive value of Prosopis glandulosa is comparable to those other species despite the perception that livestock that browse on it are more productive than those that browse on the other plant species. <br><br></p> Marks Kgosimotse Matlotlo Ditlhogo Moffat Pinkie Setshogo Gaone Mosweunyane ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 7 16 10.37106/bojaas.2020.25 Editor's Note https://bojaas.buan.ac.bw/index.php/jaas/article/view/93 <p>The views expressed in these articles are those of the author(s) and not the publisher. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use or misuse of this material.</p> Sello Alfred Likuku ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2020-04-03 2020-04-03 14 1 i ii 10.37106/bojaas.2020.93 Climate change and plant pathogen biodiversity: The case of witches’ broom outbreak on Vachellia xanthophloea (Benth.) Banfi & Galasso) in Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/43 <p>Climate change, typified by drought, floods and rising temperatures continue to affect biodiversity in the world.&nbsp; Recently, outbreaks of new insect, weed and plant pathogen species have been reported in SADC and some old ones have increased in severity while others have diminished. Examples of new insects that have threated food security and trade in the region include the fall army worm (<em>Spodoptera frugiperda</em>) and tomato leaf miner (<em>Tuta absoluta</em>). Over 50% of the Hartbeespoort Dam near Pretoria is covered by water hyacinth (<em>Eichhornia crassipes</em>) reducing property values and tourism in the area. In August 2014, witches’ broom outbreak on fever tree was first observed in Gaborone. Microscopic examination of disease signs revealed, urediospores, teliospores, aeciospores and aecia typical of <em>Ravenelia </em>sp<em>.</em> Samples were sent to the FABI, University of Pretoria where the pathogen was tentatively identified as <em>R. natalensis</em> or <em>R. hieronymi</em>. After the 2014/2015 and 2015/16 poor rain seasons few new infections were recorded in August. Following the heavy rains caused by cyclone Dineo, the epiphytotic exploded starting July 2018 and almost all fever trees in the major towns of Botswana were attacked. The witches’ brooms were also infected by powdery mildew (<em>Erysiphe</em> sp.) and <em>Diplodia</em> sp. which caused black twig dieback. The fever tree natural distribution is limited to the Tuli block but it has been introduced south as a landscape and shade tree. The tree is now invasive spreading rapidly along drainage channels and rivers around Gaborone. Currently the pathogen may be a threat to other <em>Vachellia </em>and<em> Senegalia</em> spp. in Botswana. The witches’ brooms are releasing trillions of spores into the air which may result in new human allergies. The implications of the outbreak on tree biodiversity and how the disease can be managed should be investigated.</p> E B Khonga ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2019-09-26 2019-09-26 14 1 1 7 10.37106/bojaas.2019.43 Classification, description and mapping of the vegetation in Khutse Game Reserve, Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/45 <p>There is currently no detailed classification and description of plant communities in Khutse Game Reserve (KGR), Botswana, using phytosociological techniques. The main aim of this study was to classify and describe plant communities in KGR. Classification and description of plant communities will help in understanding the plant ecology of KGR. Braun-Blanquet sampling method was applied in 91 stratified random relevés. Nine plant communities were identified and classified using Modified TWINSPAN which is contained in JUICE program. The results showed that there was a statistically significant difference in percentage cover of herbaceous plants between the different plant communities. <em>Schmidtia pappophoroides</em>-<em>Stipagrostis uniplumis</em> and <em>Heliotropium lineare-Enneapogon desvauxii </em>communities had higher cover (%) of herbaceous plants than other communities. <em>Catophractes alexandri</em>-<em>Stipagrostis uniplumis </em>community had the highest cover (%) of shrubs. There was no statistically significant difference in plant species diversity (Shannon-Wienner Index) and species evenness between plant communities, but there was a statistically significant difference in plant species richness between the different plant communities. <em>Dichrostachys cinerea</em>-<em>Grewia flava </em>community, <em>Senegalia mellifera </em>subsp. <em>detinens</em>-<em>Maytenus </em>species community and <em>Catophractes alexandri</em>-<em>Stipagrostis uniplumis </em>community had lower number of species, whereas <em>Vachellia luederitzii </em>var. <em>retinens</em>-<em>Grewia flava</em> community had the highest number (46) of plant species. This study will help the Department of Wildlife and National Parks (DWNP) to develop an updated and informed Management Plan for the reserve, which takes cognizance of the plant ecology of the reserve.</p> T. Lori M. K. Ditlhogo M. P. Setshogo P. Koosaletse-Mswela ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2019-09-26 2019-09-26 14 1 8 23 10.37106/bojaas.2019.45 Biodiversity and climate change perceptions in arid lands-implications for sustainable development in Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/47 <p>The paper considers the biodiversity and climate change perceptions in the semi-arid landscape of Botswana. Ecosystem services are essential to the planet’s equilibrium/wellbeing. However, anthropogenic influences, including climate change remain a stressor to the biodiversity resources. For Botswana, the land degradation and droughts, climate change and livelihoods are intertwined to divulge distinctive vulnerabilities and impacts. The existing action plans such as National Biodiversity Strategy and Action Plan (NBSAP), the Botswana National Action Programme to Combat Desertification (BNAP-CCD) and climate change’s nationally determined contributions (NDCs) point to the need for synergies. Research projects highlight increased vulnerabilities for various sectors, which challenge the country’s sustainability initiatives to meet the Sustainable Development Goals (SDGs), National Development Plan 11 (NDP11) and the Vision 2036 imperatives. The perception study reveals the general public’s interpretations of what is good and what are challenges, at district levels. These reveal that biodiversity or climate change are not perceived to contribute much to the ‘good’ of the country, except for 2 district groups in northern Botswana. The national challenges hinge much on biodiversity loss and climate change – hence restricting attainment of the national development priorities.</p> J. R. Atlhopheng M. G. Moshoeshoe G. Phunyuka W. Mokgopa ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2019-09-26 2019-09-26 14 1 24 31 10.37106/bojaas.2019.47 The second Symposium held in February 2018 under the theme “Biodiversity Management - A Strategy for Sustainable Development and Climate Change Adaptation and Mitigation” https://bojaas.buan.ac.bw/index.php/jaas/article/view/41 <p>The Global Taxonomy Initiative (GTI) was developed by governments through the Convention on Biological Diversity (CBD) after acknowledging the existence of taxonomic impediment to the sound management of biodiversity. The main aim of the strategy is to develop the human resources and infrastructure necessary to generate, disseminate and use taxonomic knowledge and information in a manner that assists parties in effectively implementing the convention. The National Taxonomy Committee (NTC) is a committee mandated to drive the Global Taxonomy Initiative programme of work in Botswana.</p> Marumo Kedumetse Marumo ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2019-09-26 2019-09-26 14 1 ii ii 10.37106/bojaas.2019.41 Phytochemical constituents in edible parts of anchote (Coccinia abyssinica (lam.) (cogn.)) accessions from Ethiopia https://bojaas.buan.ac.bw/index.php/jaas/article/view/16 <p>Anchote (Coccinia abyssinica) accessions from Ethiopia were tested for the presence of major phytochemicals using qualitative and quantitative methods. The qualitative tests were performed for 12 phytochemical compounds with 6 solvent extracts and water using standard methods. Quantitative analysis for important secondary metabolites included total phenols, total flavonoids, crude saponins and beta-carotene. Of the 12 phytochemicals tested, five compounds showed positive results for all the seven extracts in the tubers, whereas only two phytochemicals responded positively in the leaves. The water extract of anchote showed positive results for 11 of the phytochemicals while n-butanol showed positive results for six in both the tuber and leaf parts. The water extract also had the highest phytochemicals in both the tuber and leaf parts when compared to the other solvent extracts. Anchote leaf had the highest total phenol and flavonoid contents followed by the fruit and the least concentration was in the tuber for all the accessions. The leaf contained the highest percentage of saponins (27.65%) while tuber had the lowest (14.65%). The β-carotene content in five accessions of anchote leaf ranged from 25.9±0.03 to 35.2±0.16 µg/g. Anchote is popular in the Oromo and non-Oromo tribes in Ethiopia, because of its medicinal role. Owing to the various phytochemical compounds present in the plant further screening and identification of its active compounds is recommended.</p> Ayalew Ayalew ##submission.copyrightStatement## http://creativecommons.org/licenses/by-nc-nd/4.0 2019-03-13 2019-03-13 14 1 1 9 10.37106/bojaas.2019.16 Grain legume production and their potential for sustainable agriculture in Botswana between 2008 and 2015: a review https://bojaas.buan.ac.bw/index.php/jaas/article/view/11 <p>Pulse crops are an integral component of arable agriculture in Botswana, particularly in subsistence farming. The benefits of these crops include provision of nutrition for both human beings and livestock, as well as environmental sustainability needs. Although they have a far reaching socio-economic impact, these benefits have not been adequately characterized for inclusion in endeavors of conservation agriculture in the country. Furthermore, data on pulses are often lumped together without identifying important pulse crops grown in Botswana. The objective of this paper was to review production of pulses and their potential as components in cropping systems and conservation agriculture in Botswana. The data used in this study were obtained from reports of Ministry of Agriculture and Food Security (MOA), Statistics Botswana, FAOSTAT and other literature sources. With the ongoing changes in climate and predicted increase in incidences of drought, pulses are among crops most relevant to sustainable agriculture. They are among the most versatile because of their variability in cropping duration from early to late maturity. Their consumption ranges from fresh forms to physiologically mature grain.&nbsp; Pulses play an important role in climate change mitigation through their ability to fix nitrogen, thus reducing dependency on organic and synthetic fertilizers. They use less water from relatively shallow soil and allow for stratified soil water use for companion crops in intercropping or conserve soil water for subsequent crops in rotations. Thus pulses improve both water and nutrient use efficiencies when included in cropping systems. Their production also has a low footprint in both carbon and water. Currently, pulses are among the few highly priced crops in Botswana markets and together with the possibility of replacement of imported grain, investments in their production can generate income and improve livelihood of both farmers and consumers in Botswana. Crop production management technology involves judicious use of integrated nutrient, pest and disease management; appropriate integrated management packages that include pulses can be promoted to ensure sustainable crop production under the adverse impacts of climate change.</p> G. N. Mashungwa ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 80 90 10.37106/bojaas.2019.11 The potential for heavy metal pollution in crops from urban and peri urban horticultural farms in the Gaborone environs: a review https://bojaas.buan.ac.bw/index.php/jaas/article/view/10 <p>The introduction of urban and peri-urban agriculture (UPA) is usually characterized by high input intensity. This intensive use of chemical fertilizers, pesticides, wastewater, sludges and industrial effluents may lead to accumulation of potentially toxic metals in the soil, increasing the geological background levels and exceeding the capacity to immobilize them. Besides being environmental pollutants of which the toxicity is a problem of increasing significance for ecological reasons, heavy metal accumulation in the food chain is highly dangerous for human health. The objective of this review was to highlight the potential problems that may arise as a consequence of irrigating crops with sewage water as well as using fertilizers and pesticides. A review of literature has shown that different types of fertilizers contain some quantities of heavy metals that may buildup in the soil as well as be taken up by crops. In addition to using fertilizers, the use of treated and sometimes partially treated and untreated water by UPA farmers around Gaborone may lead to heavy metal accumulation in soil as well as in crops, posing a danger to human beings. In Botswana there is limited information concerning heavy metal accumulation in soils even though there is a high use of agrochemicals in vegetable production in UPA land use systems. Lack of such information necessitates research on the impact of the application of fertilizer, sewage water (treated and untreated) and metal-based pesticides on the quality of the vegetable produce coming from UPA.</p> L.C Obuseng ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 71 79 10.37106/bojaas.2019.10 Evaluation of Bradyrhizobium formulations on performance of soybean grown on soil without a long-term history of the crop https://bojaas.buan.ac.bw/index.php/jaas/article/view/9 <p>Farmers have raised concerns about the inability of some commercial soybean inoculants to elicit effective nodulation. Nodulation failure has been attributed to, among others, high temperatures, soil acidity and type of inoculant used. This work examined the influence of two <em>Bradyrhizobium japonicum</em> inoculant formulations on soybean grown on soil without a soybean cropping history for about eight years. The experiment was conducted in a controlled environment facility at the University of KwaZulu-Natal. The treatments were two levels of a liquid formulation of the <em>Bradyrhizobium</em> WB 74 initially consisting of 2.6×10<sup>9</sup> colony forming units ml-1 and one level of a powder formulation containing a minimum of 6.5×10<sup>8</sup> live cells g<sup>-1</sup>. The results showed that applying the two formulations of <em>B. japonicum</em> to seed, enhanced soybean nodule number, leaf number, nutrient concentration and uptake compared to the control treatment, and both powder and liquid formulations enhanced yield components to the same extent. Although the low concentration of the liquid formulation was less effective in increasing nodule number, other responses it elicited were comparable to the high concentration of the liquid and powder formulations. We conclude that small differences may exist between commonly available commercial inoculants of Bradyrhizobium WB 74 but they are effective in promoting nodulation and growth of soybean, and that reported major nodulation failures may be attributed to management factors other than inoculant formulation <em>per se</em>.</p> J. A. Adjetey ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 66 70 10.37106/bojaas.2019.9 Lime and foliar application of molybdenum affects nodulation, nutrient uptake and pod production in soybean grown in acid soils https://bojaas.buan.ac.bw/index.php/jaas/article/view/8 <p>Soil acidity is commonly ameliorated with lime while little attention is given to the application of molybdenum which is deficient in acid soils. Molybdenum is an important component of the nitrogenase enzyme essential for the symbiotic nitrogen fixing bacteria.&nbsp; An experiment was conducted in a controlled environment at the University of KwaZulu-Natal to evaluate the effect of lime and molybdenum on nodulation, growth and shoot nutrient content of soybean. The experiment was a randomised complete block design with three rates of lime applied at 0, 2650 and 4280 kg ha<sup>-1</sup> and molybdenum as ammonium molybdate at 0 and 0.5 g L<sup>-1</sup>. Lime significantly (p&lt;0.01) increased the uptake of Ca and P but decreased that of Mn. Also, increasing lime levels positively influenced most of the important plant growth parameters measured in the study. Molybdenum application significantly increased nodule formation but did not influence the concentration and uptake of the nutrients measured. Lime application also improved soil Ca and Mg but reduced Mn and exchangeable acidity levels at the end of the study.&nbsp; The treatment combination of lime at 4280 kg ha<sup>-1</sup> and ammonium molybdate at 0.5 g L<sup>-1 </sup>gave the best result in nearly all parameters tested and it can hence be concluded that this combination improves both the nutrient uptake and nodulation of soybean grown in soil with very high acid saturation.</p> J. A. Adjetey ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 57 65 10.37106/bojaas.2019.8 The effect of treating growing gilts with either Ractopamine or Reporcin on pork characteristics https://bojaas.buan.ac.bw/index.php/jaas/article/view/7 <p>The pork industry is constantly seeking economical and sustainable strategies that will improve production efficiencies and meat quality. Such successful improvements will be of value even here in Botswana to improve food security. The evaluation of pork characteristics after use of these strategies is important. This study aimed at evaluating the effect of a beta-agonist (BA - Ractopamine) and porcine growth hormone (rpGH - Reporcin) on the pork characteristics of the longissimus dorsi (LD) muscle of adult gilts (starting weights of 85<u>+</u>5kg) treated for 27 days under three treatment groups (15 animals per treatment group). The control group was fed a standard commercial diet ad-libitum, while the beta-agonist (BA) group were also fed ad-libitum the standard commercial diet containing Ractopamine (20mg/kg) and the growth hormone (rpGH) group were fed the commercial diet ad-libitum and administered Reporcin (10mg) intramuscularly every other day until the day before slaughter. No significant differences were observed between treatment groups regarding the gilts’ carcass weights after 27 days of treatment (control – 81.98kg; BA – 86.97kg and rpHG – 84.51kg). However, LD muscle from gilts of the growth hormone (1.569%) and Ractopamine (1.502%) groups had significantly lower lipid content compared to the control group at 1.873% (p &lt;0.001), but no significant differences were observed between groups regarding fatty acid profiles. The two growth promoters can thus be locally adopted for use to improve feed utilization, pork production and to lower lipid content in pork of growing gilts without deleteriously affecting fatty acid composition.</p> M.H.D. Mareko ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 51 56 10.37106/bojaas.2019.7 Beekeeping practices and physicochemical properties of honey produced in Lerala village, Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/4 <p>This study was conducted to evaluate the physicochemical properties of <em>Apis mellifera</em> honey produced in Lerala village and to assess the beekeeping practices. Sale of honey is an important source of income for beekeepers in Lerala village. There are two types of honeybee production systems in the study area: traditional backyard beekeeping and forest honey harvesting. A total of six honey samples obtained from two sources (modern hive and forest) were analysed for physicochemical properties following standard procedures. A semi-structured questionnaire was used to assess beekeeping practices by interviewing 15 individuals who have experience in beekeeping. The &nbsp;average values for moisture content, total ash, free acidity, reducing sugars, sucrose, pH, water-insoluble solids and hydroxymethylfurfural of honey samples obtained from modern hives &nbsp;were 18%, 0.24%, 31 meq/kg, 56.6%, 1.88%, 4.24, 0.05 g/100g and 26.6 mg/kg, respectively. The corresponding values for honey obtained from the forest were 17.7%, 0.28%, 27.7 meq/kg, 58%, 2%, 5.18, 0.07 g/100g and 10.9 mg/kg, respectively. Honey source significantly (P≤0.05) influenced the pH, reducing sugars and sucrose contents of the honey samples while ash, free acidity, water-insoluble solids and moisture content were not significantly (P&gt;0.05) different between the two sources of honey. The pH, sucrose and reducing sugars content of forest honey samples were significantly (P≤0.05) higher than honey obtained from modern hives. All the parameters analysed were within the limits set by the Codex Alimentarius Commission for honey. The major challenges faced by beekeepers in the study area include lack of skills and knowledge of beekeeping, weak extension services and lack of bee handling and honey processing equipment. Thus, there is a need for training of beekeepers on improved beekeeping practices and provision of inputs such as modern hives and honey handling and processing equipment to farmers.</p> L Bareki ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 22 32 10.37106/bojaas.2019.4 Meliponiculture and physicochemical properties of honey produced by the African stingless bee Plebeina hildebrandti Friese in Kalakamati village, Botswana https://bojaas.buan.ac.bw/index.php/jaas/article/view/13 <p>This study was conducted to assess the harvesting practices in Kalakamati village of honey produced by the African stingless bee <em>Plebeina hildebrandti </em>Friese and to determine the physicochemical properties of this honey. To understand stingless bee honey harvesting practices, a semi-structured questionnaire was prepared and 15 individuals who have experience in collecting stingless bee honey were interviewed. The physicochemical properties of four honey samples were analysed following standard procedures. The stingless bee honey had average moisture (28.4%), reducing sugar (61%), apparent sucrose (2.4%), free acidity (36 meq/kg), pH (4.77), total ash (0.42%), hydroxymethylfurfural (HMF) (17.82 mg/kg) and water-insoluble solids content of 0.07%. All the parameters comply with the Tanzanian standard for stingless bee honey whereas all but moisture content agrees with the European standard for honey from <em>Apis</em> <em>mellifera</em>. Moisture content of the stingless bee honey in the present study is higher than the 21% EU standard for <em>Apis mellifera</em> honey. In Kalakamati village, honey from stingless bees is collected from the bush and stingless bees are not kept by farmers. According to the respondents, honey from stingless bees is consumed as it is, is used as a substitute for sugar in tea and for its medicinal value to treat cough, stomach ache and flu. The results suggest that honey produced by stingless bees in Kalakamati village is of good quality as it generally meets international quality standards. Honey production from stingless bees could contribute to poverty alleviation and food security in the study area if appropriate interventions are made.</p> W. Bafo ##submission.copyrightStatement## https://bojaas.buan.ac.bw 2019-03-12 2019-03-12 14 1 33 42 10.37106/bojaas.2019.13