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Shumbusha D.,University of KwaZulu - Natal | Shimelis H.,University of KwaZulu - Natal | Laing M.,University of KwaZulu - Natal | Asiimwe T.,Rwanda Agriculture Board RAB
Acta Agriculturae Scandinavica Section B: Soil and Plant Science | Year: 2017

The genetic diversity available in sweetpotato has not been explored to develop dual-purpose sweetpotato varieties (DPSVs). The objectives of this study were to assess the level of phenotypic diversity present among sweetpotato varieties grown in Rwanda, and to select suitable parents for breeding DPSVs. Fifty-one diverse sweetpotato genotypes were evaluated in field trials conducted at the Rubona and Karama experimental stations of the Rwanda Agriculture Board using a 6 × 9 unbalanced alpha lattice design with three replications. Genotypes and sites showed significant interaction (P < .05), indicating differential response of genotypes in fresh root yield (FRY), root dry matter content, dry root yield (DRY), marketable root number, marketable root weight, flowering frequency and harvest index. The top two genotypes selected for their high FRY were RW11-4923 (20.9 t ha−1) and RW11-2419 (20.18 t ha−1). RW11-4923 and Wagabolige were the best performers for vine yield, producing 23.67 and 23.45 t ha−1 of vines, respectively. Ukerewe performed well for its DRY (7.09 t ha−1), while RW11-4923 had the highest mean dry vine yield (5.17 t ha−1). RW11-2910 and 8-1038 had root-to-vine ratios of 2.0 and 1.5, respectively, suggesting their suitability as breeding parents, to breed DPSVs. Two main phenotypic groups with 10 sub-groups were detected through cluster analysis. Principal component analysis showed that the first four components accounted for 76.33% of the phenotypic variation present among the 51 genotypes. The selected sweetpotato genotypes that had a combination of high storage root yields and heavy vine production should be used as parents in developing DPSVs, concurrently incorporating farmer-preferred traits. © 2017 Informa UK Limited, trading as Taylor & Francis Group


Nduwumuremyi A.,University of KwaZulu - Natal | Melis R.,University of KwaZulu - Natal | Shanahan P.,University of KwaZulu - Natal | Asiimwe T.,Rwanda Agriculture Board RAB
Food Security | Year: 2016

Physiological postharvest deterioration (PPD) and late bulking are among the traits that make cassava an unattractive crop in many environments. This study aimed at assessing the main constraints of cassava production, the effects of late bulking, the losses due to PPD and the factors affecting adoption of new cultivars in Rwanda. A participatory rural appraisal (PRA) and a baseline survey were conducted in March-May 2014 in three agro-ecological zones in the country using a multistage sampling method. Cassava was grown on 0.29 ha out of 0.69 ha total average land possession per household. The majority of cassava farmers (59.1 %) practised intercropping as their land holding is small. Average yield was 21.8 t ha−1. A number of constraints was identified, particularly the lack of clean cuttings, viral diseases, late bulking cultivars, drought, limited information and knowledge, weathered soils, insufficient fertilizers, land shortage, lack of markets and effective storage techniques. Loss due to PPD was estimated at 11.9 % of total production per year. Piecemeal harvest and underground storage of roots were the main practices used to delay PPD. Change in colour and taste, rotting, difficulty in removing skin and increase of fibres in the flesh were the farmers’ methods for assessing PPD. Time to harvest varied from district to district and was attributed to genetic x environment interactions. The use of late bulking varieties and the lack of yield production of other crops resulted in reduced food availability and potential food crises. Farmer preferences, information and extension services, performance, quality, market acceptability and cutting production influenced the adoption of new cassava cultivars. Thus, breeding objectives targeting the end user preferences could enhance the adoption of new cultivars. © 2016 Springer Science+Business Media Dordrecht and International Society for Plant Pathology


Mutimura M.,University of KwaZulu - Natal | Ebong C.,Rwanda Agriculture Board RAB | Rao I.M.,International Center for Tropical Agriculture | Nsahlai I.V.,University of KwaZulu - Natal
Tropical Animal Health and Production | Year: 2016

Rearing heifers for dairy cow replacement is a challenge in smallholder dairy farms in the tropics due to feed shortage. The objective of this study was to evaluate Brachiaria hybrid cultivar Mulato II as a forage resource for improving growth performance of dairy heifers under cut-and-carry feeding system in Rwanda. Sixteen crossbred (Ankole × Jersey) heifers (mean weight 203 ± 35 kg) were randomly allocated to two dietary treatments viz: Mulato II with 2 kg/day of commercial concentrates (MCC) and Napier grass (Pennisetum purpureum) with the same supplement (NCC), for a period of 12 weeks. Mineral lick and water were provided ad libitum. Daily feed intake and fortnightly live weight were measured. Average daily gains and feed conversion ratio (FCR) were calculated. Results showed that absolute daily dry matter intake (g DMI/day) and relative intake (g/kg of metabolic body weight—BW0.75) were higher in heifers fed on MCC than in heifers fed on NCC (P < 0.001). FCR was lower (P < 0.001) in MCC than NCC diets. Final body weight (FBW) and body weight gain (BWG) did not differ between the two groups of heifers (P > 0.05). Average daily weight gain (ADWG) also not differed significantly (P > 0.05). Based on numerical body weight changes and nutritive values, Mulato II showed potential to be integrated into local cut-and-carry feeding systems for better heifer rearing to facilitate dairy cow replacement. © 2016 Springer Science+Business Media Dordrecht


Mutimura M.,University of KwaZulu - Natal | Ebong C.,Rwanda Agriculture Board RAB | Rao I.M.,International Center for Tropical Agriculture | Nsahlai I.V.,University of KwaZulu - Natal
Tropical Animal Health and Production | Year: 2015

Smallholder dairy farmers in Rwanda use diversity of resources to cope with endemic feed shortages. However, there is inadequate real farm data to support farmer decisions on choices of options. The main objective of this study was to evaluate nutritional quality of feed types that farmers use in different agro-ecological zones of Rwanda. Samples of feed types were collected from 90 randomly selected households in the low- and mid-high-altitude zones of Rwanda and analysed for proximate composition, contents of metabolisable energy (ME), organic matter digestibility (OMD) and neutral detergent fibre digestibility (NDFd). Rumen fermentation characteristics and efficiency of energy utilisation were examined by determining partitioning factor (PF). Results showed that only five out of 24 feed types were common in both districts. Chemical composition, OMD, ME, NDFd and PF of these feed types differed significantly (P < 0.05) in their nutritional attributes. This suggests that a common feed composition table can be used as a component of the decision support tool for rational feed resource development and utilisation in the smallholder farms in the selected agro-ecologies of Rwanda. © 2015, Springer Science+Business Media Dordrecht.


Placide R.,University of KwaZulu - Natal | Shimelis H.,University of KwaZulu - Natal | Laing M.,University of KwaZulu - Natal | Gahakwa D.,Rwanda Agriculture Board RAB
Tropical Agriculture | Year: 2015

During phenotypic evaluation of crop plants many traits are simultaneously evaluated. These traits are often highly interrelated, evaluation of all these traits is costly and may not enhance selection response. The objectives of this study were to use Principal Component Analysis (PCA) to identify representative traits for phenotypic characterization of sweet potato, and thereby to identify superior clones for breeding. Fifty four sweet potato genotypes were field evaluated using 26 phenotypic traits under a 9 × 6 unbalanced alpha lattice design with three replications at the Karama and Rubona Research Stations in Rwanda. The PCA identified seven principal components (PC) that explained 77.83% of total variation present in the genotypes. Nineteen useful traits were identified as the main traits for effective phenotypic characterization of sweet potato, showing high correlations with the seven PCs. Genotypic variance had the greatest contribution to the total sources of variation for flowering rate (65.3%), yield of storage root (52.4%), vine yields (62.8%), total biomass (56.3%), harvest index (61.1%), weight of biggest root (50.6%) and dry matter content (57.5%). Genotypes 8-1038, Kwezikumwe and K513261 were identified as high yielding with the greatest flowering ability, while OTADA 70,9-486, Purple 297,2005-146,8-1039, NASPOT 9, 2005-020, Newkaogo, 440163 and OTADA 24 were all high yielders of both storage roots and vines. The identified principal traits and genotypes may be useful in sweet potato breeding in Rwanda and similar agro-ecologies. © 2015 Trop. Agric. (Trinidad).


Placide R.,University of KwaZulu - Natal | Shimelis H.,University of KwaZulu - Natal | Laing M.,University of KwaZulu - Natal | Gahakwa D.,Rwanda Agriculture Board RAB
HortScience | Year: 2015

The role of farmers and their production constraints and preferences are important for sweetpotato breeding and adoption of cultivars and agronomic production packages. The objective of this study was to assess farmers’ perception, production constraints, preferences, and breeding priorities of sweetpotato in selected agro-ecologies of Rwanda. A total of 495 farmers were surveyed in 2013 in eight representative districts: Bugesera and Kayonza in the Eastern Province, Gakenke and Rulindo in the Northern Province, and Gisagara, Huye, and Muhanga in the Southern Province. Data were collected through a participatory rural appraisal (PRA) methodology using a semistructured questionnaire and focus group discussions. Pairwise comparison of 16 food crops allocated sweetpotato as one of the five important food crops for food security and income generation. Drought stress, unavailability of improved cultivars and planting material, and pest and disease damage were perceived to be the five main constraints limiting sweetpotato production, contributing to 17.3%, 15.0%, 12.9%, 11.7%, and 11.5%, respectively. The most important sweetpotato cultivar traits had high yield, early maturity, drought tolerance, disease and pest tolerance, and good culinary taste at 22.5%, 18.5%, 15.4%, 12.7%, and 10.1%, respectively. The characteristics of good storage roots identified by farmers included high dry matter content, good culinary taste, good shape, root size, and sweetness representing 27.4%, 18.8%, 16.1%, 11.6%, and 9.4%, respectively. Each agro-ecological zone has its own specific sweetpotato production constraints and farmers’ preferences, necessitating targeted breeding of different sweetpotato cultivars for each agro-ecological zone for enhanced productivity and successful adoption of cultivars. © 2015, American Society for Horticultural Science. All rights reserved.


Musoni A.,Higher Institute of Agriculture and Animal Husbandry ISAE | Musoni A.,Makerere University | Kugonza D.R.,Makerere University | Gahakwa D.,Rwanda Agriculture Board RAB
Livestock Research for Rural Development | Year: 2013

This study on adoption of cattle husbandry technologies at an African national research station used the Rwanda Agriculture Board's Rubona station as a case study and was conducted through a survey of 92 randomly-selected cattle keeping households in Rusatira Sector of Huye District where the station is located. Respondents were interviewed using a pre-tested structured questionnaire and data were analysed using standard statistical procedures. The study revealed that all the respondents knew at least one cattle-related service/technology provided by Rubona station. The majority (61.9%) ranked station services as very good, 29.4% as good, while to 8.7%, the services were bad. While only 63% of all households reared crossbred cattle, all respondents credited the station which intensively promotes grade dairy germplasm. Over half of the respondents used bovine artificial insemination (AI) service provided by station staff. Among the users of AI, 54.3% relied on it for genetic improvement, 20.6% targeted disease control, while others claimed uses that are not technically associated with it. A high (P<0.05) proportion of farmers (48%) reported frequent failure of AI as the problem which limits its use. Analysis of forage seed sources showed that Rubona station was the major provider (58.7%). Also, the station was singled out as the main contributor to disease prevention in the study area, through its novel "livestock improvement parks". Generally, livelihoods were attributed to the station suggesting that many of its technologies are being sufficiently acquired. Correlation analysis showed that education level positively influenced adoption of improved cattle breeds (r=+0.62, P=0.001), AI (r=+0.55, P=0.001), and castration (r=+0.57, P=0.001) while age of household head negatively influenced adoption of exotic breeds (r= -0.56, P=001), AI (r= -0.48, P=0.001), however, gender was not a significant factor. It is concluded that neighbours of research stations do learn a lot from the stations, but the adoption of what they learn depends on a number of factors. This study therefore recommends strengthening of the extension service on cattle management targeting the elders and the non-educated, since these were the least adopters.


Rukundo P.,University of KwaZulu - Natal | Shimelis H.,University of KwaZulu - Natal | Laing M.,University of KwaZulu - Natal | Gahakwa D.,Rwanda Agriculture Board RAB
Australian Journal of Crop Science | Year: 2013

Sweetpotato is a relatively drought tolerant crop providing the highest dry matter content for human consumption. High dry matter content is the main characteristic preferred by consumers and processors of sweetpotato. There is a continued need to develop and release new and high yielding sweetpotato varieties possessing high dry matter content. The objective of this paper is to review important aspects in the breeding of the crop to achieve high storage root yield and increased dry matter content. The paper highlights development and synthesis processes of dry matter of sweetpotato storage root, gene actions and correlation between traits associated with dry matter accumulation, breeding of sweetpotato for high dry matter content, approaches to screening of clones with high dry matter content and effects of genotype by environment interaction on yield and dry matter content.


PubMed | University of KwaZulu - Natal, International Center for Tropical Agriculture and Rwanda Agriculture Board RAB
Type: Journal Article | Journal: Tropical animal health and production | Year: 2016

Rearing heifers for dairy cow replacement is a challenge in smallholder dairy farms in the tropics due to feed shortage. The objective of this study was to evaluate Brachiaria hybrid cultivar Mulato II as a forage resource for improving growth performance of dairy heifers under cut-and-carry feeding system in Rwanda. Sixteen crossbred (Ankole Jersey) heifers (mean weight 203 35 kg) were randomly allocated to two dietary treatments viz: Mulato II with 2 kg/day of commercial concentrates (MCC) and Napier grass (Pennisetum purpureum) with the same supplement (NCC), for a period of 12 weeks. Mineral lick and water were provided ad libitum. Daily feed intake and fortnightly live weight were measured. Average daily gains and feed conversion ratio (FCR) were calculated. Results showed that absolute daily dry matter intake (g DMI/day) and relative intake (g/kg of metabolic body weight--BW(0.75)) were higher in heifers fed on MCC than in heifers fed on NCC (P < 0.001). FCR was lower (P < 0.001) in MCC than NCC diets. Final body weight (FBW) and body weight gain (BWG) did not differ between the two groups of heifers (P > 0.05). Average daily weight gain (ADWG) also not differed significantly (P > 0.05). Based on numerical body weight changes and nutritive values, Mulato II showed potential to be integrated into local cut-and-carry feeding systems for better heifer rearing to facilitate dairy cow replacement.


Ndayambaje B.,Umutara Polytechnic | Mushonga B.,Umutara Polytechnic | Ebong C.,Rwanda Agriculture Board RAB
Journal of Animal and Veterinary Advances | Year: 2013

Feeding guides for animals are based on body weight Advisory service providers often depend on Heart Girth (HG) and Body Conditions Scores (BCS) as proxy indicators of Live Body Weight (LBW) in mature cattle. But the relationship is affected by a number of factors including breed, parity and physiological status of the animal. There is a tacit gap in understanding the relationships between BCS and LBW and their implications on animal management decisions in developing countries including Rwanda. A study was therefore conducted to determine the effect of genotype and parity on the relationship between BCS and LBW in lactating Ankole cows and their crossbreds with Friesian genotypes. Results revealed that BCS and LBW were more correlated (r≥0.90) in Ankole than in crossbred cows (r≤0.40). The correlation improved the correlation to similar levels in all breeds (r≥0.90) when parity was considered independently. The cows gained 11 -20 kg/Unit BCS because of low frame size. It was concluded that BC Systems were pertinent management tools for developing countries and the relationships between BCS and LBW could be an important selection tool for dairy cattle improvement in Rwanda. © Medwell Journals, 2013.

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