IITA Manuscripts-unpublished
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Item Long read sequencing and assembly of wild diploid relatives and cultivars in support of banana breeding programs(Preprint, 2024-09) Chen, A.; Zhou, X.; Decker, K.; Havecker, E.; Du, E.; Brown, A.; Aitken, E.A.B.; Shah, T.; Uwimana, B.; Hresko, C.; Swennen, R.; Lowdon, R.F.Banana is an important fruit and staple crop, which is vital for food and income security in developing countries. A genomics initiative was undertaken as part of the Global Alliance against TR4 (Tropical Race 4 of Fusarium Wilt of Banana) Alliance, with Bayer Crop Science, International Institute of Tropical Agriculture, and University of Queensland to collectively accelerate the breeding efforts in Eastern Africa. The goal of this project is to develop genomics resources to improve banana breeding, productivity, and quality traits amid a changing climate and shifting disease pressures for breeding. Here, we present the PacBio HiFi sequencing, assembly, and comparative analysis of seven genomes of wild and edible diploid banana accessions belonging to subspecies considered important progenitors to cultivated banana varieties and part of breeding programs. This banana genome resource will help power genome editing, a pangenome effort, and conventional breeding programs for germplasm improvement.Item Redefining agricultural education through vocational training: Start Them Early Program in Kenya(Brief, 2022-04) International Institute of Tropical Agriculture; STEPItem Farmers' guide to management of aflatoxins in maize and groundnuts in Africa: trainer's guide(Manuscript-unpublished, 2019) International Institute of Tropical Agriculture; AgResultsItem Farmers' guide to management of aflatoxins in maize in Africa: pre-harvest and post-harvest recommendations(Manuscript-unpublished, 2019) International Institute of Tropical Agriculture; AgResultsItem Cocoa farmer's segmentation in Ghana(Manuscript-unpublished, 2019) Dalaa, Mustapha Alasan; Kofituo, R.K.; Asare, R.Item Climate smart stepwise investment pathway for cocoa farmers in Ghana(Manuscript-unpublished, 2019) Dalaa, Mustapha Alasan; Kofituo, R.K.; Asare, R.Item Epidemiology and control of cowpea mosaic in Western Nigeria(Manuscript-unpublished, 1973) Glimer, R.Cowpea mos1aic is a serious virus disease of cowpea in the Ibadan area. Disease incidence may reach 80% at harvest. The disease also occurs in soybean, sword bean, Mexican yam bean, and lima bean. Two well-defined disease syndromes occur in cowpea: a bright yellow fleck or mosaic (YF type) and a green mott1e with leaf distortion and puckering (GB type). GB type isolates are general1y more injurious than YF type isolates, but the two are closely related serologically to each other and to a CPMV isolate from Arkansas, USA. Economic injury to cowpea depends on three factors: virus isolate, tolerance of the infected cowpea cultivar, and most important, age of the host plant at time of infection. Early infections (7 days after emergence) reduce yields ~y 40-60% but late infections (after flowering) cause reductions of duly 5-10%. The virus is transmitted through seeds from infected plants (about 1-5%) and such infections appear to supply inoculum for secondary spread in the field. In addition to the known vector, Ootheca mutabi1is several new vectors have recently been identified: two beetles, Luperodes lineata and Nematocerus ac rbus, the grasshoppers Zonocerus variegatus and Catantops spissus, and t e thrips Sericothrips occipitalis and Taeniothrips sjostedti. The most Beasib1e means of control of the disease is the use of host immunity, present in several cowpea cultivars. Preliminary data indicate that more than one recessive gene is involved. Breeding programs will be complicated,to some extent, by differences in pathogenicity of virus isolates.Item Nematode attack on cowpeas in Nigeria(Manuscript-unpublished, 1973) Caveness, F.E.Cowpeas are attacked by 24species of nematodes distributed among 15 general. Fifteen of these 24 species of plant-parasitic nematodes have been founding Nigeria. The most destructive on local cowpea are three species of the root-knot nematode. The root-knot nematodes are also the most wide spreading Nigeria being found abundantly in all states. The reinform nematode has also been proved capable of reducing cowpea yields in Nigeria and is widely distributed. Both kinds of nematode scan cause yield reductions of 20 to 30percent.Thelife cycles of the root-knot nematodes and the reniform nematode have been studied for Nigeria and are essentially the same as reported in the literature for other tropical countries.Item IITA, the lead research partner facilitating agricultural solutions to overcome hunger and poverty in subSaharan Africa: the critical role of appropriate soil fertility and land use management(Presentation, 2015-09) Vanlauwe, Bernard; Sanginga, N.For IITA to thrive and meet the expectations of the wider agricultural community in sub-Sahara Africa it must: (i) continue to occupy the Research for Development (R4D) high ground and raise its profile among local and international partners; (ii) conduct rigorous, well-focused research and assure its delivery to end users; (iii) manage its human, physical and financial resources more effectively and (iv) expand its partnership with both the public and private sectors and more convincingly advocate for needed policy change at many levels across the continent. These are challenging goals, and closing the yield gaps of key commodities in a sustainable manner, as referred to in our Refreshed Strategy 2012–2020, requires doubling the current human and financial resources available to IITA over the next eight years. During the past four years. IITA has increased its funding from the $47 million in 2011 to $143 million today and the number of international staff from the 115 to 230. It is making progress with its partners to raise over 11 million Africans out of poverty and redirect over 7.5 million hectares of under-utilised, marginal and degraded lands to more productive and sustainable use, and guided by and contributing to the four System Level Outcomes (SLOs) as defined by the CGIARhreducing rural poverty, increasing food security, correcting under-nutrition, and promoting more sustainable management of natural resources. IITA has prioritised formulation and delivery of its R4D products. As the Dalberg review commissioned by the CGIAR Consortium Board concludes, the CGIAR has fallen short of effectively translating its excellent science into impact on the rural poor. IITA has recently achieved several research breakthroughs from its core research projects that have the potential to greatly improve the lives and livelihood of these clients. Furthermore, IITA is fine-tuning its delivery systems as indicated through the early achievements of our Business Incubation Platform (BIP) and its Aflasafe, Nodumax and GoSeed product lines. IITA is refining its strategy to direct rural youth from diverse competencies toward agribusiness careers through the Youth in Agribusiness (IYA) program. We are engaging the private sector and strengthening our partnership with National Agricultural Research Institutions (NARIs) and regional organisations by establishing and coordinating major platforms such as the West Africa Biosciences platform; the Pan-African Platform for Soil Research for Development and a Regional Research and Training Centre to link climate change with biodiversity and biotic stresses.Item IITA in the News(Manuscript-unpublished, 2005) International Institute of Tropical AgricultureItem IITA in the News(Manuscript-unpublished, 2004) International Institute of Tropical AgricultureItem PCR detection of Xanthomonas vasicola PV. Musacearum in banana: implication for mat management to control BXW wilt(Manuscript-unpublished, 2008) Adikini, S.; Beed, Fenton D.; Tripathi, L.; Tusiime, Geoffrey; Mwangi, M.; Aritua, Valentine; Kyamanywa, S.; Miller, S.B.Item Effect of phytotoxic factors and potassium nutrition on Banana Xanthomonas Wilt(Manuscript-unpublished, 2008) Atim, M.; Beed, Fenton D.; Tripathi, L.; Tusiime, Geoffrey; Mwangi, M.; Kubiriba, JeromeItem Policies and development strategies to achieve agricultural transformation in the cocoa belt of Cameroon(Manuscript-unpublished, 2008) Gockowski, J.; Nyemeck, J.; Njikam, O.; N'chare, A.; Mva Mva, J.Item Survey of insects visiting banana male buds in Eastern Democratic Republic of Congo and their contamination by the bacterium causing wilt(Manuscript-unpublished, 2008) Fiaboe, K.K.M.; Beed, Fenton D.; Mwangi, M.; Katembo, M.; Ndungo, V.Item Antibiotic effects of aqueous extract of honeybee propolis against Xanthomonas vasicola P.V. Musacearum(Manuscript-unpublished, 2008) Fiaboe, K.K.M.; Beed, Fenton D.; Mwangi, M.; Kubiriba, Jerome; Tushemereirwe, Wilberforce K.Xanthomonas vasicola p.v. mucasearum (Xvm) is the causal agent of banana bacterial wilt which is currently constraining banana production in Eastern Africa. One mode of transmission is by insect vectors and studies in Uganda have shown that drosophilids, honey and stingless bees are of particular importance. It is not yet known if bee hives consist pools for Xvm multiplication and spread or if the propolis’ antimicrobial defense at hives entrance can eliminate Xvm. The present study aimed at investigating the presence of antibiotic compounds andor organisms contained in water extract of propolis that can be effective against Xvm. Fresh propolis from hives was soaked in water for 15 days at 37oC and afterwards filtered through a Whatman® filter paper No. 1 (185mm diameter). Two types of extract solutions were prepared: a) non sterile propolis extract solution (NSP) and b) sterile-filtered extract solution (SP), prepared by filtering again through a Whatman® sterile filter to remove all living organisms (25mm diameter and 0.2 µm pore size). Each extract was separately mixed with Xvm cell suspension (2 x 106 CFUml) at a ratio of 1:4 (vv, extractXvm suspension) and 100 µl was added to both non-selective medium (YPGA) and selective medium (SM) (containing 5-fluorouracil and Cephalexin) in 9cm Petri dishes The control consisted of Xvm cell suspension mixed with sterile water in place of the propolis extract. Bacterial growth was evaluated after 72hrs using a scale varying from 0 to 5, based on colony coverage of the medium surface. Growth of Xvm on YPGA was not significantly different between the control and sterilized extract (mean growth scores of 4.9 ± 0.1 and 4.8 ± 0.1, respectively). However the non sterile extract completely inhibited the growth of Xvm colonies on both YPGA and SM media. A, as yet unidentified, gram positive bacteria (PB) was obtained from NSP with mean growth scores of 5.0 ± 0.1 on both media. Subsequent studies consisted of growing a pure culture of PB on YPGA media at the same time as Xvm with eight spots of Xvm (2mm diameter each) surrounded by nine spots of PB. After 72hrs, the mean growth scores were 0.1 ± 0.1 and 4.9 ± 0.1 for Xvm and PB, respectively. The Xvm colonies showed initial convex growth morphologies when adjacent to PB colonies and were then killed. The present results demonstrate the presence of at least one antagonistic bacterial species in the propolis, suggesting possible suppression of Xvm on insect body at hive entrance. These findings warrant further study for possible biocontrol of Xvm.Item Technique dannihilation des males pour la suppression de B. invadens au Benin=Male annihilation for the control of Bactrocera invadens and Ceratitis cosyra in mango orchards(Manuscript-unpublished, 2008) Hanna, R.; Gnanvossou, D.; Grout, T.Item Effect of dual endophyte inoculations on plant colonization, and control of Radopholus similis and the banana weevil(Manuscript-unpublished, 2008-10) Paparu, P.; Dubois, T.; Coyne, Danny L.; Viljoen, AltusThe root burrowing nematode Radopholus similis and the banana weevil Cosmopolites sordidus are major pests of banana in the Lake Victoria basin region. An integrated pest management approach that includes habitat management, biological control, host plant resistance and chemical control is currently used to control populations of the two pests. Biological control strategies with potential to control the banana weevil and R. similis include the use of entomopathogenic fungi Beauveria bassiana and non-pathogenic Fusarium oxysporum endophytes of banana. The current study was designed to investigate the effect of dual endophyte inoculations on control of the two pests in ‘Nabusa’ ( spp., AAA-EA group). Endophytic F. oxysporum isolate V5w2 known to reduce R. similis numbers in screenhouse pot trials was inoculated together with isolate Emb2.4o, known to be effective against the banana weevil. Root and rhizome colonization was higher.Item Evaluation of East African highland banana land races and hybrids for resistance to banana nematodes in semiarid Uganda(Manuscript-unpublished, 2008-10) Wasukira, A.; Coyne, Danny L.; Dubois, T.; Dusabe, J.; Pillay, M.; Lorenzen, J.H.Radopholus similis, Helicotylenchus multicinctus and Meloidogyne spp. are among the major nematode pests of banana worldwide. Nematode management through exploitation of genetic sources of resistance is widely encouraged, especially in resource poor countries. A number of hybrids have been developed and assessed for resistance to nematodes under screenhouse conditions and on station. The current study was designed to test the resistance of the genotypes, both land races and hybrid selections that had exhibited some nematode resistance in screening exercises, in a semi-arid location. Peeled and hot water treated suckers of 51 banana genotypes were planted out into the field in Eastern Uganda, (semi-arid ecosystem) where the natural nematode field populations represented the inoculum. The plot management was divided into one of high or low, represented by application of spear grass mulch (~15 cm depth every six months) or no mulch, respectivelyItem Relationship between root and shoot growth traits during the plant crop and first ratoon in banana and plantain (Musa spp.) and its implications for perennial cultivation on degraded Ultisols in southeastern Nigeria.(Manuscript-unpublished, 2008) Blomme, Guy; Swennen, Rony L.; Soka, G.; Turyagyenda, L.F.; Tenkouano, A.The effect of cycle on root system and shoot development was studied for two crop cycles (plant crop and first ratoon). The study revealed that shoot and root system development declined from the plant crop to the first ratoon for plants grown on degraded Ultisols in south-eastern Nigeria.