Participatory consumer evaluation of twelve sweetpotato varieties in Kenya

Eleven improved sweetpotato varieties; “Kemb10, SPK004, Mugande, Namaswakhe, K117, Polista, Bungoma, Odinga, 292-H-12, Zapallo” and “Nyathi Odiewo (improved) ”, were tested against four popular farmer varieties; “Nyathi Odiewo (local), Jayalo, Amina and Kuny kibuonjo” for consumer preference. The experiment was laid out in a randomized complete block design with 12 treatments replicated four times in mother and baby trial with farmers’ involvement. The study was conducted in farmers’ fields in four locations covering the major sweetpotato production Agro-Ecological Zones (AEZ ) of southwest Kenya namely; Kabondo AEZ, Upper Midland2 (UM2), Ndhiwa, Low Midland2 (LM2), Rangwe, Low Midland1 (LM1) and Kendu, Low Midland3 (LM3). The trials were planted in May and September 2005 both long and short rains, respectively. Ten participating and ten non-participating farmers per location formed a panel and evaluated the mother trial for consumer preference. Focused group discussions were held to determine farmers’ perception for evaluation. Data was collected on consumer preference: - yield, taste, aroma, ease to cook and texture. There were differences in yield with variety “Mug and” yielding highest followed by “K117 Nyathi Odiewo, Namaswakhe” and “Kemb10” respectively across locations. Farmers’ preferred local varieties “Nyathi Odiewo” and “Kuny kibounjo” were comparable to the improved varieties. Variety “Zapallo” and the local varieties; “Jayalo” and “Amina” had lower yielding. “Odinga” was most preferred for consumption followed by “Nyathi Odiewo Kemb10, SPK004, Polista, 292-H-12” and the local checks. Farmers’ involvement is crucial in evaluation of preferred sweetpotato varieties for consumption. However, varieties “K117” and “Mugande” have potential to increase farmers production

Inadvertent presence of genetically modified elements in maize food products in Kenyan markets

Kenya has a biosafety law and has tested genetically modified (GM) maize under confinement and containment, but has neither released nor commercialized any GM crop. This study assessed various maize food products from the Kenyan farms and markets for the inadvertent presence of GMOs. It assessed the possibility of ‘gene-flow’ to the maize farms near the Kenya Agricultural Research Institute (KARI), Kiboko where Bt maize was grown in confined field trials (CFT) during 2005 to 2006. The multistage sampling technique was used, while the polymerase chain reaction (PCR) and lateral-strip methods were used to analyze 120 food samples. Of these, 6.7% tested positive for cry1Ab, a globally commercialized gene, but were negative for cry1Ba, a non-commercialized gene. Neither cry1Ab nor cry1Ba genes were found in any of the maize certified seed samples. No ‘gene-flow’ was detected within the vicinity of the Kiboko CFT site. The maize imported into Kenya contained Bt genetic elements. Nevertheless, the confinement regulatory measures employed during the CFTs at Kiboko were effective. There is a need to enforce declaration of GM or non-GM and conduction of regulatory detection of food imports and for labelling of food products to enable consumers to make informed choices on what they buy and consume.Keywords: cry1Ab, cry1Ba, biosafety, GMOs, Bt maize.African Journal of Biotechnology Vol. 12(31), pp. 4881-489

Surface sterilant effect on the regeneration efficiency from cotyledon explants of groundnut (Arachis hypogea L.) varieties adapted to eastern and Southern Africa

Five groundnut (Arachis hypogea L.) varieties - ICGV-12991, ICGV-99568, ICGV-90704, CG-2 and Chalimbana - that are adapted to Eastern and Southern Africa were compared to variety JL 24 for their regeneration response in tissue culture. Sodium hypochlorite and mercuric chloride were compared for efficiency as sterilizing agents and subsequent effect on regeneration. All five varieties formed shoot buds that elongated well on shoot elongation medium. ICGV-90704 and Chalimbana performed betterthan the other three varieties for shoot organogenesis although all varieties produced healthy rooted plants in vitro that were successfully transferred to the greenhouse where they exhibited normal growth, flowering and seed set. Both sterilizing agents were suitable, but mercuric chloride was lessharmful than sodium hypochlorite. This study established a basis for genetic engineering activities on African groundnuts in the future

Experiences in effective communication on transgenic technology in Africa – the case of the insect resistant maize for Africa (IRMA) project

The Insect Resistant Maize for Africa (IRMA) Project, aimed to improve food security through developing and deploying locally adapted stem borer resistant maize varieties using both conventional and biotechnology mediated methods, especially Bt technology. This technology uses a gene from the soil bacterium Bacillus thuringiensis (Bt) to create transgenic maize varieties. Transgenic technologies have been a controversial and emotive topic in recent years, and the IRMA project was launched against this backdrop. To ensure widespread acceptance of the IRMA project and its Bt technology, the project carefully planned and implemented its communication and public awareness strategy. Following its public launch in March 2000, the project promoted an open communication environment and continuously engaged with stakeholders to update them on progress. The project achieved this through targeted and diverse communications products such as media articles and broadcast news pieces, newsletters, websites, videos and reports. To complement these, the project conducted annual stakeholders’ meetings, and specialized training for frontline project staff and collaborators, especially extension agents. This paper reviews the IRMA Project’s public awareness and communication strategy and analyzes its effectiveness.Key words: Transgenic technology, Bacillus thuringiensis (Bt) maize technology, communication, public awareness, insect resistant maize for Africa (IRMA) project

Testing public Bt maize events for control of stem borers in the first confined field trials in Kenya

Transgenic maize (Zea mays L), developed using modified genes from the bacterium Bacillus thuringiensis (Bt), controls stem borers without observable negative effects to humans, livestock or the environment, and is now sown on 134 million hectares globally. Bt maize could contribute to increasing maize production in Kenya. Nine public Bt maize events of cry1Ab and cry1Ba genes were tested in confined field trials site (CFTs) to assess the control of four major Kenyan stem borer species. Leaf damage rating, number of exit holes and tunnel length were scored in the field evaluations. Leaf area consumed and mortality rates among stem borers were scored in the leaf bioassays in a Biosafety Level II laboratory, located at the Kenya Agricultural Research Institute (KARI), National Agricultural Research Laboratories (NARL). Field evaluations showed that Bt maize controlled Chilo partellus with mean damage scores of 1.2 against 2.7 for the non-Bt CML216 control. Laboratory bioassays showed high control for Eldana saccharina and Sesamia calamistis, with mean larval mortality of 64 and 92%, respectively. However, substantial control was not observed for Busseola fusca. These results showed that Bt maize could control three of the four major stem borers in Kenya with mortality records of 52.7% for B. fusca, 62.3% for E. saccharina and 85.8% for S. calamistis. Additional Bt genes need to be sought and tested for effective stem borer control in all maize growing ecologies in Kenya.Key words: Maize, Bt, stem borers, confined field trials

Divergência genética em cultivares de morangueiro, baseada em caracteres morfoagronômicos

Os caracteres morfoagronômicos são tradicionalmente usados na caracterização de cultivares e no estudo da divergência genética, contribuindo na definição de estratégias para o melhoramento genético. Este trabalho teve por objetivo avaliar a divergência genética por meio de caracteres morfoagronômicos de 11 cultivares de morangueiro (Aromas, Camarosa, Camino Real, Campinas, Diamante, Dover, Oso Grande, Sweet Charlie, Toyonoka, Tudla e Ventana), nas condições climáticas da região Centro-Sul do Paraná. Foram analisados 29 caracteres morfoagronômicos relacionados com a planta, folha, flor, fruto e aquênios do morangueiro. As similaridades genéticas foram calculadas por meio de análise multivariada e, os cultivares, agrupados com base na matriz de similaridade genética, usando-se UPGMA. Dentre os 29 caracteres morfoagronômicos avaliados, oito apresentaram diferenças não significativas (p < 0,05). A similaridade média foi de 38%, variando de 19 (aromas e camino real) a 62% (Camino Real e Camarosa; Aromas e Sweet Charlie). O dendrograma alocou os cultivares em quatro grupos, contudo, essa divisão não foi coerente com a origem e genealogia dos cultivares. O cultivar Tudla apresenta elevado potencial "per se" para utilização em programas de melhoramento. O cruzamento mais promissor com base nos caracteres morfoagronômicos é entre os cultivares Camarosa e Campinas

Data from: On the origin of sweet potato (Ipomoea batatas (L.) Lam) genetic diversity in New Guinea, a secondary centre of diversity

New Guinea is considered the most important secondary centre of diversity for sweet potato (Ipomoea batatas). We analysed nuclear and chloroplast genetic diversity of 417 New Guinea sweet potato landraces, representing agro-morphological diversity collected throughout the island, and compared this diversity with that in tropical America. The molecular data reveal moderate diversity across all accessions analysed, lower than that found in tropical America. Nuclear data confirm previous results, suggesting that New Guinea landraces are principally derived from the Northern neotropical genepool (Camote and Batata lines, from the Caribbean and Central America). However, chloroplast data suggest that South American clones (early Kumara line clones or, more probably, later reintroductions) were also introduced into New Guinea and then recombined with existing genotypes. The frequency distribution of pairwise distances between New Guinea landraces suggests that sexual reproduction, rather than somaclonal variation, has played a predominant role in the diversification of sweet potato. The frequent incorporation of plants issued from true seed by farmers, and the geographical and cultural barriers constraining crop diffusion in this topographically and linguistically heterogeneous island, has led to the accumulation of an impressive number of variants. As the diversification of sweet potato in New Guinea is primarily the result of farmers’ management of the reproductive biology of their crop, we argue that on-farm conservation programmes that implement distribution of core samples (clones representing the useful diversity of the species) and promote on-farm selection of locally adapted variants may allow local communities to fashion relatively autonomous strategies for coping with ongoing global change