PABRA Journal Articles

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Soil carbon enhancing practices: a systematic review of barriers and enablers of adoption
(Journal Article, 2019-12) Karanja Ng'ang'a, Stanley; Anyango Jalang'o, Dorcas; Girvetz, Evan Hartunian
Sustained adoption of soil carbon enhancing practices (SCEPs) at scale remains an aspiration goal to maintain sufficient amount of soil carbon in household farms in order to impact on the sustained farm productivity caused by sustained soil fertility. The objective of this study is to systematically evaluate the current evidence base to identify: (a) which factors enable or constrain adoption of SCEPs and hence maintain soil carbon in Kenya and Ethiopia; (b) to be able to lessons learnt concerning what influences the adoption of the SCEPs for the purpose of maintaining soil fertility among smallholder farms; and (c) how this can be improved going into the future for the purpose of formulating appropriate policies in Kenya and Ethiopia in both the short and long run. A systematic review was conducted using established review methodology and extensive searches of published and unpublished literature sources. Data extraction and quality appraisal of quantitative, qualitative and case studies that met the inclusion criteria were conducted while checking for reliability. A broad range of interrelated enabling and constraining factors was identified for the SCEPs. All the factors matter, and some of most of these factors are important to be considered during planning and implementation of SCEPs aiming at promoting soil carbon sequestration. Despite the limitation in the quantity of evidence, this systematic review provides a useful starting point for the scaling up programmes to ensure more effective adoption of SCEPs. This review also underscores the need for a multidisciplinary approach in understanding what determines the adoption of SCEPs to capture a holistic view.
Climbing bean as a solution to increase productivity in land-constrained environments: Evidence from Rwanda
(Journal Article, 2019-03) Katungi, Enid M.; Larochelle, Catherine; Mugabo, Josephat R.; Buruchara, Robin Arani
Climbing bean is a potential solution to increase the agricultural sector productivity and sustainability. Using nationally representative bean-producing household data collected in Rwanda, this study identifies factors that influence the decision to switch from cultivating bush to climbing bean and quantifies the impact of climbing bean adoption on yield. About 50% of bean-producing households grow climbing bean, a substantial increase over the past 15 years. Elevation, population pressure, and drought shocks are important drivers of climbing bean adoption. Adoption of climbing bean increases yield by 23% among adopters and has the potential to increase yield by 48% for non-adopters. Findings from this study provide important information for the development of agricultural policies and programs in Rwanda and elsewhere.
Responses to selection for yield traits and key diseases among common bean genetic pyramids across locations
(Journal Article, 2019-11-02) Okii, Dennis; Badji, Arfang; Odong, Thomas L.; Talwana, Herbert; Tukamuhabwe, Phineas; Magdalena, William; Gepts, Paul L.; Mukankusi, Clare Mugisha
Role of fixing nitrogen in common bean growth under water deficit conditions
(Journal Article, 2020-02) Fenta, Berhanu Amsalu; Beebe, Stephen E.; Kunert, Karl J.
In common bean (Phaseolus vulgaris L), limited information is available if potential of nodulation and symbiotic nitrogen fixation is associated with the expression of traits that confer better adaptation to drought conditions. Adaptive traits were therefore measured in N‐fixing bean lines BAT 477, DOR 364, and PAN 185 and in nonnodulating lines BAT 477‐NN and DOR 364‐NN. Drought affected growth in all bean lines and decreased chlorophyll content but more in DOR 364‐NN and BAT 477‐NN, and also reduced nodule size with highest reduction in DOR 364 (21.6%). Loss of nitrogen fixation under drought conditions was further associated with lower water use efficiency, measured as carbon isotope ratio of 13C/12C, and lower %N in shoots when compared to capability to fix nitrogen. Loss of symbiotic nitrogen fixation in mutant bean lines DOR 364‐NN and BAT 477‐NN negatively affected root architectural traits under drought. Under drought conditions, line BAT 477‐NN had about 50% lower values for all root architectural traits, such as root angle, strongly emphasizing an association of capability to fix nitrogen with root development. An association between capability to fix nitrogen and maintaining a better harvest index and seed yield was also found in the study. Under well‐watered conditions, all N‐fixing lines had a higher harvest index and seed yield (2.6–2.8 t of seed yield/ha) in comparison with the two nonfixing bean lines (1.4 t/ha). Although the harvest index and seed yield declined due to drought in all tested lines, this decline was only significant for line DOR 364‐NN (harvest index) and lines DOR 364‐NN and BAT 477‐NN (seed yield). Our study has overall demonstrated an important association between the capability of maintaining atmospheric N‐fixation and expression of traits conferring better adaptation to drought conditions with any change in nitrogen fixation affecting these traits.
Diversity and interaction of common bacterial blight disease-causing bacteria (Xanthomonas spp.) with Phaseolus vulgaris L.
(Journal Article, 2019-02) Tugume, Joab K.; Tusiime, Geoffrey; Sekamate, Allan Male; Buruchara, Robin Arani; Mukankusi, Clare Mugisha
Common bacterial blight (CBB) is associated with common bean (Phaseolus vulgaris L.), an important grain legume for human consumption worldwide. The disease, caused by Xanthomonas spp. is spread mainly through seed. This paper focuses on the diversity of X. axonopodis pv. phaseoli and X. fuscans subsp. fuscans and interactions between related bacteria and the bean host. Review has suggested that the diversity and taxonomic studies of these pathogens are not exhaustive, especially in areas where detailed molecular analysis has not been conducted and previous characterizations were based on phenotypic features and PCR-based techniques. Also, no study has confirmed differential pathogenicity on bean genotypes based on compatible versus incompatible reactions. However, isolates react differently to wild and domesticated bean sources of resistance in common bean genetic backgrounds. A systematic approach will be required to investigate global changes in gene expression among different sources of resistance in a common bean background. The bacterial isolates that cause CBB should be functionally characterized using genotypes containing major quantitative trait loci (QTL) for CBB resistance. These studies will increase understanding of resistance and how it is manipulated by pathogens.
Household-oriented benefits largely outweigh commercial benefits derived from cattle in Mabalane District, Mozambique
(Journal Article, 2018) Karanja Ng'ang'a, Stanley; Ritho, Cecilia; Herrero, Mario; Fraval, Simon
In Sub-Saharan Africa, research aimed at improving household livelihoods through cattle often targets commercial benefits while neglecting household-oriented benefits. The latter are rarely articulated, and their comprehensive role in livelihoods is little understood by policymakers. The main aim of this study was to assess household-oriented benefits of cattle as a basis for formulating appropriate policies. Data were collected from 192 households selected through multistage random sampling in Mabalane District of Mozambique in 2009. The main objectives of cattle raising were identified and ranked in order of importance by using the analytical hierarchy procedure. The vast majority (98%) of households kept cattle primarily to derive various types of household-oriented benefits such as draft power, financing, insurance, saving, social status and bridewealth. Only 2% of households kept cattle mainly for commercial benefits. The households secured financing, insurance and saving primarily by capital accumulation through herd expansion, for example after a good crop harvest, using the profit to purchase a young calf, an ox or a heifer. Households reporting social prestige as an important objective for raising cattle were mainly those already with high social status. In Mabalane District, a large herd of cattle is considered evidence of one’s ability to manage communally owned resources. This suggests that the functions of draft power, financing, insurance and saving play important roles in the livelihoods of most of agro-pastoral households in Mozambique—arguably more important than meat and milk. The reliance on financing, insurance and saving benefits of cattle, as well as the low level of milk and meat marketing, could be explained by the low level of development within the district, exacerbated by the civil war that ended in the 1990s.
Reduction in nutritional quality and growing area suitability of common bean under climate change induced drought stress in Africa
(Journal Article, 2018-11) Hummel, Marijke; Hallahan, Brendan F.; Brychkova, Galina; Ramírez Villegas, Julián Armando; Guwela, Veronica; Chataika, Bartholomew Y.E.; Curley, Edna; McKeown, Peter C.; Morrison, Liam; Talsma, Elise F.; Beebe, Stephen E.; Jarvis, Andy; Chirwa, Rowland; Spillane, Charles
Climate change impacts on food security will involve negative impacts on crop yields, and potentially on the nutritional quality of staple crops. Common bean is the most important grain legume staple crop for human diets and nutrition worldwide. We demonstrate by crop modeling that the majority of current common bean growing areas in southeastern Africa will become unsuitable for bean cultivation by the year 2050. We further demonstrate reductions in yields of available common bean varieties in a field trial that is a climate analogue site for future predicted drought conditions. Little is known regarding the impact of climate change induced abiotic stresses on the nutritional quality of common beans. Our analysis of nutritional and antinutritional compounds reveals that iron levels in common bean grains are reduced under future climate-scenario relevant drought stress conditions. In contrast, the levels of protein, zinc, lead and phytic acid increase in the beans under such drought stress conditions. This indicates that under climate-change induced drought scenarios, future bean servings by 2050 will likely have lower nutritional quality, posing challenges for ongoing climate-proofing of bean production for yields, nutritional quality, human health, and food security.
Application of molecular markers in breeding for bean common blight resistance in South Africa
(Journal Article, 2011) Fourie, D.; Herselman, L.
Sequence characterised amplified region (SCAR) markers, linked to four independent quantitative trait loci (QTL) in XAN 159 and GN #1 Nebr. sel. 27, are available for indirect selection of resistance to common bacterial blight in Phaseolus vulgaris. Existing SCAR-markers, SU91, BC420, BC409 and SAP6, were evaluated for potential use in the South Africa breeding programme. Segregating populations of progenies developed through backcross breeding with cultivars Teebus and Kranskop as susceptible recurrent parents, and XAN 159 and Vax 4 as resistant donor parents were evaluated for presence of existing markers. Presence of all four markers in improved Teebus lines (XAN 159 derived) confirmed transfer of resistance in these lines. Marker BC420 was absent in XAN 159 derived Kranskop-lines. These lines were only moderately resistant when tested in the greenhouse, indicating that the QTL linked to this marker is important in order to obtain high levels of resistance. Progenies from backcrosses with Kranskop as recurrent parent using Vax 4 have exhibited high levels of resistance and presence of all markers found in Vax 4 confirmed transfer of resistance. Marker-assisted selection can successfully be implemented in breeding for common bacterial blight resistance in South African materials.
Characterisation of bacterial brown spot pathogen from dry bean production areas of South Africa
(Journal Article, 2011) Muedi, HTH; Fourie, D.; Mclaren, NW
Pseudomonas syringae pv. syringae (Pss) causes bacterial brown spot (BBS) of beans (Phaseolus vulgaris L.), with yield losses of up to 55% in South Africa. Pss has a wide host range and for many of these, the pathogen has been biochemically and genetically characterised. However, few studies have been conducted on Pss isolated from beans. The aim of this study was to assess the biochemical and genetic variability of Pss isolates collected from dry bean producing areas in South Africa. Pure isolates were subjected to LOPAT tests and SyrB gene assessment. Biolog GN Microplates were used to assess carbon substrate utilisation. The SyrB gene was present in 42% of isolates. The Biolog GN Microplates showed biochemical variation among isolates. Variable genomic patterns were observed in 48.5% by the BOX A1R primer and in 37.1% of isolates by the ERIC 2 primer. Thus, variability exists in Pss populations of dry beans.
Genetic variation for drought resistance in small red seeded common bean genotypes
(Journal Article, 2011) Rezene, Y; Gebeyehu, S; Zelleke, H.
Common bean (Phaseolus vulgaris L.) productivity is low in major growing regions of Ethiopia mainly due to drought, caused by low and erratic rainfall. A field experiment was carried out at Gofa in Southern Ethiopia, to assess genetic variability for drought resistance in forty-nine small red seeded common bean genotypes of both local and foreign origin. The genotypes were evaluated under two soil moisture regimes, non-stress (NS) and drought stress (DS). Drought stress was initiated at flowering by withholding application of irrigation water. The average linkage method of clustering grouped the forty-nine genotypes grown under drought stress condition in five clusters. The maximum distance was found between Cluster I and Cluster III. Pattern of variation examined through principal component analysis (PCA) involving morpho-physiological traits showed that the first four PCs accounted for more than 74% of the total variation, of which 59.9% was contributed by the first two PCs. The first principal component alone explained 49.9% and was highly correlated with seed yield, harvest index and geometric mean. The second PC explained 9.7% of the total variation and was highly correlated with days to maturity and drought susceptibility index. Both PCs had higher relative contributions to the total diversity and were the ones that most differentiated the genotypes.
Improvement of common bacterial blight resistance in South African dry bean cultiver teebus
(Journal Article, 2011) Fourie, D.; Herselman, L.; Mienie, C.
Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli is an important seed-borne disease of dry beans in South Africa. Development of resistant cultivars is considered the best control measurement for the disease. Backcross breeding was used to improve BB resistance in the small white canning bean, cv. Teebus, using resistance sources XAN 159 and Wilk 2. High resistance levels in near-isogenic lines, developed in two independent breeding programmes, indicated successful transfer of resistance from both sources. Presence of SCAR-markers, SU91 and BC420, in 35 of 39 XAN 159 derived Teebus lines and all lines derived from Wilk 2, confirmed successful resistance transfer. AFLP studies conducted to determine genetic relatedness of two near-isogenic Teebus lines, showed a similarity of 96.2% with the maximum similarity between these lines and Teebus being 93.1%. One cultivar, Teebus-RCR2 with yield similar to Teebus and improved resistance to CBB has been released from the programme.
Inheritance of resistance to angular leaf spot in yellow beans
(Journal Article, 2011) Muthomi, J.W.; Muimui, Kennedy K.; Kimani, P.M.
Angular leaf spot (Phaeoisariopsis griseola (Sacc) is an important disease of common bean (Phaseolus vulgaris L.) in most parts of Africa, causing yield losses of 40-80%. This study was carried out to determine the inheritance of resistance to angular leaf spot in yellow beans. Biparental crosses were done between susceptible yellow bean genotypes and angular leaf spot resistant parents to generate F1, F2 and backcrosses. Resistance was evaluated in a screen house and field after inoculation with Phaeoisariopsis griseola. The F1 were resistant, indicating that resistance was dominant. There was no significant deviation from the expected 3:1 ratio for resistant to susceptible in the F2 population, confirming that resistance to angular leaf spot was both monogenic and dominant. The backcross to Lusaka Yellow showed a 1:1 segregation ratio, while the backcrosses to Mexico 54 were all resistant. Pembela was susceptible to angular leaf spot, while the F1 were resistant. The ratio of 3:1 represents resistant : susceptible F2 populations. All backcrosses to Mexico 54 were resistant, confirming that resistance to angular leaf spot in Mexico 54 is controlled by a single dominant gene. The results of the study showed that resistance to angular leaf spot in yellow beans is governed by a single dominant gene. This can be used to improve the local landraces by incorporating angular leaf spot resistance and high yield traits.
Pathogenic and genetic variation in Xanthomonas axonopodis pv. Phaseoli and its fuscans variant in Southern Africa
(Journal Article, 2011) Fourie, D.; Herselman, L.
Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli and its fuscans variant, X. axonopodis pv. phaseoli var. fuscans is a widespread disease of dry beans in South Africa. Variation within pathogen populations has been reported and in order to breed for resistance it is important to investigate whether variation exists within the local pathogen population. One hundred and forty three common bacterial blight isolates from 44 localities in four countries, were inoculated onto eight Phaseolus acutifolius lines that differentiate between pathogenic races. This differential set was expanded to include resistant genotypes, XAN 159, GN #1 Nebr. sel 27, Wilk 2, Wilk 6, Vax 4, Vax 5 and Vax 6 and cv. Teebus as susceptible check. Genetic variation within nine selected Xap and Xapf isolates and a non-pathogenic Xanthomonas isolate, was studied using RAPD and AFLP analysis. Genotypes XAN 159, Wilk 2, Wilk 6, Vax 4, Vax 5 and Vax 6 were resistant to all isolates, while GN #1 Nebr. sel 27 and cv. Teebus were susceptible. Isolates varied in aggressiveness on cv. Teebus; however, the pathogenic reaction on the set of differentials indicated that all, but one isolate, grouped in what has been reported as race 2. Thus, results based on reaction of the majority isolates, suggest the absence of different races. However, the distinct differential reaction recorded for a single isolate, may prove to represent another, as yet unrecorded, race of this pathogen. Both RAPD and AFLP analyses revealed high frequency of DNA polymorphism among isolates and could distinguish between Xap, Xapf and a non-pathogenic isolate. Differences between Xap and Xapf isolates demonstrate that these are two distinct groups of bacteria.
Resistance and inheritance of common bacterial blight in yellow bean
(Journal Article, 2011) Muimui, Kennedy K.; Kimani, P.M.; Muthomi, J.W.
Common bean (Phaseolus vulgaris L.) is the most important food legume among the pulses. It is a cheap source of protein, especially in Sub-Saharan Africa. However, bean production is constrained by bacterial diseases, of which common bacterial blight (Xanthomonas axonopodis p.v. phaseoli) is prevalent in Africa. The objective of this study was to transfer resistance to common bacterial blight and determine its inheritance in yellow beans. Sources of resistance were CIAT lines, Wilk 2 and VAX 6, which were crossed with susceptible Lusaka yellow and Pembla. The parents, F1, F2 and backcross progenies were inoculated with X. axonopodis and the resulting blight severity determined. Quantitative traits, including days to flowering, number of pods, and seed yield were also determined. The F1 and backcrosses to the resistant parents were all resistant, while the F2 and backcrosses to the susceptible parents segregated in 3:1 and 1:1 ratios, respectively. Additive genetic effects were observed in quantitative traits like days to flowering, plant height, days to maturity and yield. Therefore, resistance to common bacterial blight is controlled by a single dominant gene. The resistant parents Wilk 2 and VAX 6 could be used to improve bean varieties that are susceptible to common bacterial blight.
Seed storage proteins ARL2 and its variants from the apalocus of wild tepary bean G40199 confers resistance to acanthoscellides obtectus when expressed in common beans
(Journal Article, 2011) Kusolwa, PM; Myersm, JR
Wild tepary beans (Phaseolus acutifolius) contain arcelins and arcelin-like (ARL2) proteins that are co-expressed with other proteins of the arcelin, α-amylase inhibitors and phytohemagglutinins (APA) locus. Arcelin and ARL2 protein from a wild tepary bean accession G40199 were transferred into common bean cultivars ICA Pijao and Rojo. Inbred backcross lines were developed and selected for segregation of the proteins at BC2F2:3 generations. Seeds from homozygous, segregating lines expressing the arcelin and ARL2, plus those without the proteins, were used for screening against resistance to A. obtectus. Significant delay of 63 days for 50% adult emergence and reduced number of emerged F1 of A. obtectus adults were observed in backcross lines with homozygous expression of arcelin and ARL2 tepary bean proteins. Furthermore, a reduction in size and weight of emerged adult insects to almost half was observed. This work demonstrates the superior resistance common bean backcross lines to A. obtectus conferred by the presence of the APA proteins introgressed from tepary bean.
Susceptibility of South African dry bean cultivars to bacterial diseases
(Journal Article, 2011) Fourie, D.
Dry beans are an important crop in South Africa with the annual bean consumption being approximately 120 000 t. The crop is annually subjected to a number of biotic constraints such as bacterial diseases that can cause serious yield losses especially when the climate is conducive to diseases. The use of resistant varieties is an effective way of reducing the risk of crop failure and deployment of resistance requires knowledge on the susceptibility of cultivars. Twenty-one locally grown commercial dry bean cultivars were evaluated at Potchefstroom in South Africa to evaluate the resistance to common bacterial blight, halo blight and bacterial brown spot. Results indicated that South African cultivars differed in susceptibility to bacterial diseases. Cultivars Teebus, Cerillos, PAN 146 and PAN 159 were most susceptible to common bacterial blight with Monati and OPS-RS2 having low levels of resistance. Negative correlations (r=-0.44) (P<0.001) between disease ratings and yields were obtained in the common bacterial blight trial. Levels of resistance to halo blight were observed with small seeded cultivars generally being more resistant than large seeded types. A negative correlation (r=-0.35)(P=0.001) was obtained between halo blight rating and yield. Cultivars differed regarding susceptibility to bacterial brown spot with the majority having adequate resistance. Teebus, Cerillos, Bonus and PAN 159 were most susceptible, with Mkuzi exhibiting highest levels of resistance. No correlation was obtained between disease rating and yield. Although a number of cultivars exhibited field resistance to halo blight and bacterial brown spot, all cultivars were more or less susceptible to common bacterial blight. Common bacterial blight can be considered the most important bean bacterial disease in South Africa. Improvement of common bacterial blight resistance in South African cultivars is necessary for yield stability.
A cost-benefit analysis of farmer based seed production for common bean in Kenya
(Journal Article, 2011) Katungi, Enid M.; Karanja, D.; Wozemba, D.; Mutuoki, T.; Rubyogo, Jean-Claude
Community based informal seed production has recently gained popularity as an alternative to the formal seed sector of disseminating new crop varieties including the common bean. This is because farmer produced seed is readily available and is more affordable by most farmers than certified seed. This study examined the profitability of farmer based common bean seed production in Kenya. The study used data collected from farmers and one seed company participating in seed multiplication. The principal finding was that farmer based common bean seed production was a profitable enterprise and was less sensitive to price fluctuations. Compared to certified common bean seed production, net profit margins were five times higher for certified common bean seed than for farmer based common bean seed production. With the current varieties, profitability depends on access to irrigation and good agronomy.
Factors influencing smallholder farmers’ bean production and supply to market in Burundi
(Journal Article, 2011) Birachi, Eliud Abucheli; Ochieng, J.; Wozemba, D.; Ruraduma, Capitoline; Niyuhire, M.C.; Ochieng, D.
Common bean (Phaseolus vulgaris L) is a major staple food in Burundi; thus increasing its production and marketing has the potential for raising incomes of the farming households. In the country, bean outputs have been declining for decades, yet demand for the crop in East Africa has surged considerably. This study was conducted in Burundi to assess the determinants of quantity produced and marketed by smallholder farmers. A total of 380 farmers obtained through a multistage sampling technique, constituted the study sample. Constraints to production and supply of beans to markets include lack of productive assets, lack of improved varieties and inadequate use of fertilisers. Results with regard to these constraints indicate that a unit increase in the value of productive assets is likely to lead to about 10 percent increase in production of beans; while changing to improved bean varieties may increase production by 22%. In addition, a kilogram increase in fertiliser use is likely to raise bean quantities produced by about 10%. Constraints that affect quantities of beans marketed by farmers include levels of production and losses due to transport problems. Thus, an increase in quantity produced will lead to an almost 30% increase in marketed quantities, while reduction in transport losses will lead to an increase in marketed quantities by about 12%. However, an increase in quantity of beans stored for food will lead a reduction in marketed beans by about 19%, implying that storage of beans may not be targeted at the market but for food security purposes. Efforts that promote collective action among farmers while encouraging increasing the proportion of land under beans are likely to enhance bean production and consequently marketable surplus.
Inheritance of resistance to common bacterial blight in common bean
(Journal Article, 2011) Chataika, Bartholomew Y.E.; Bokosi, J.M.; Chirwa, R.M.
The common bean (Phaseolus vulgaris L.) is an important grain legume crop in Malawi where it is grown by small holder farmers for food as well as for sale. Among the many diseases that limit crop productivity is the common bacterial blight caused by Xanthomonas axonopodis pv phaseoli (Xap). Effective breeding for resistance to Xap requires understanding of the model of inheritance for resistance. A study to determine the inheritance of resistance to Xap in common bean was carried out in Malawi. Two established bean varieties originating from local landraces in Malawi (Chimbamba and Nasaka), plus one line (RC 15) from the breeding programme at Bunda College of Agriculture, were used as recipient (susceptible) parents; while Vax 6 from CIAT was the donor (resistant) parent. The progenies were advanced to F2 generations in greenhouses. The F2 populations were evaluated for resistance to Xap. The results showed that one recipient parent, Chimbamba, which is supposedly homogeneous, behaved like a segregating population and, therefore, modified the phenotypic ratios of the progenies. A Chi-square test using data generated from populations resulting from the three recipient parents showed that the inheritance of resistance to Xap was controlled by two major genes with possible minor genes involvement. The same was true when a Chi-square test was used to analyse the pooled data across populations generated from the three recipient parents (Chimbamba, Nasaka and RC 15), suggesting that inheritance of resistance to Xap was controlled by two major genes
Multiple disease resistance in snap bean genotypes in Kenya
(Journal Article, 2011) Wahome, S.W.; Kimani, P.M.; Muthomi, J.W.; Narla, R.D.; Buruchara, Robin Arani
Snap bean (Phaseolus vulgaris L.) is an important export vegetable crop, produced mainly by small to medium scale farmers under various disease constraints. Disease resistant varieties can reduce reliance on fungicides, and enhance the capacities of smallholder farmers to meet the stringent European export requirements for allowable fungicide residues. This study was carried out to identify snap bean lines with multiple disease resistance to angular leaf spot (Phaeoisareopsis griseola), anthracnose (Collectotrichum lindemuthianum) and rust (Uromyces appendiculatus). Seven groups of snap bean populations of different generations, and 45 bush snap bean lines, including local checks, were evaluated for resistance to the three diseases at two locations in Kenya. The disease with the highest severity was rust, followed by angular leaf spot. Among the advanced lines, two bush lines (KSB 10 W and KSB 10 BR), and one climbing line (HAV 130) had consistent multiple resistance to angular leaf spot, anthracnose and rust at both locations. Nine lines and 674 single plants were selected from populations showing multiple disease resistance. Resistance in selected lines reduced angular leaf spot, anthracnose and rust severity by 17, 16 and 36%, respectively. The multiple disease resistant lines were not the highest yielders but had the highest number of pods per plant. Climbing snap bean lines had thick pods that could reduce pod quality

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