For further information contact: ciat-bean@cgiar.org

• Improved, small-seeded, bean germplasm that is resistant to major biotic and abiotic stresses and has greater nutritional and market value
• Improved, large-seeded, bean germplasm that is resistant to major biotic and abiotic stresses and has greater nutritional and market value
• Strategies developed for managing diseases and pests in bean-based cropping systems
• Developed, evaluated, and widely disseminated improved cultivars and management practices in partnership with NARS, regional networks, NGOs, and farmers
• Strengthened the institutional, organizational, and collaborative capacity of NARS and subregional networks in Africa and Latin America
  
  

Output 1: Improved, Small-Seeded, Bean Germplasm that is Resistant to Major Biotic and Abiotic Stresses and Has Greater Nutritional and Market Value

Developed Germplasm Tolerant of the Abiotic Stresses of Drought and Low Soil Fertility

• More than 150 drought-tolerant lines were identified from a second cycle of crosses to combine drought tolerance with resistance to bean golden-yellow mosaic virus (BGYMV).
• The first group of lines with Brazilian grain types was selected. These will form the basis of crosses with high-iron beans for northeast Brazil to improve nutritional quality.
• Field evaluations of 36 promising bred lines and accessions over two seasons indicated that two accessions of Phaseolus acutifolius (G 40159 and G 40068) and two bred lines of P. vulgaris (RAB 650 and SEA 23) were outstanding in their adaptation to water stress. The superior performance of the two accessions of P. acutifolius under drought was associated with their ability to mobilize photosynthates to developing grain and to use the acquired N more efficiently for grain production.
• Field evaluations of 121 recombinant inbred lines (RILs) of the cross MD 23-24 × SEA 5 indicated that two lines (MR 81 and MR 25) were superior in their adaptation to drought. The superior performance of these two lines was associated with higher values of pod harvest index and seed TNC content, indicating the importance of mobilizing photosynthates to pods and seeds in common bean under rainfed conditions.
• Greenhouse evaluations for differences in root distribution among five common bean genotypes grown in large soil cylinders indicated that SEA 5, BAT 477, and G 21212 were deep rooted, compared with BAT 881 and MD 23-24.
• Field evaluation of 49 genotypes over three seasons indicated that two landraces (Carioca and G 21212) and two bred lines (MAR 1 and SEA 5) had the highest seed yield in Al-toxic soils. A significant negative relationship was observed between seed yield and seed P content, indicating that greater seed filling and P-use efficiency (g seeds produced per g P uptake) contributed to higher yield in Al-toxic soils.
• Collaborative research with the University of Hannover showed that Al-induced callose formation is not a suitable parameter for assessing genotypic differences in Al resistance in common bean.
• Greenhouse screening of 66 RILs of the cross G 5273 × MAM 38 resulted in four lines—HF14137-19, HF14137-26, HF14137-98, and HF14137-88—being identified as relatively more resistant to Al.
• Accessions of P. coccineus presented substantial vigor in a soil with high Al saturation, indicating that they may have important genes for tolerating Al.
• Greenhouse screening of 30 RILs of the cross BAT 477 × DOR364 resulted in four lines—BT21138-50, BT21138-83-1-3, BT21138-83-1-1, and BT21138-25—being identified as superior in their adaptation to low P supply, according to total root length, number of root tips, and total root biomass per plant.
• In Nicaragua and Quilichao (Colombia), tolerance of low soil fertility proved to be either as or more important than drought tolerance for confronting two abiotic stresses at once.

Developed Germplasm with Multiple Resistance to Diseases

• Four genotypes (G 22623, G 10909, G 3005, and G 1368) were identified as combining resistance to pathogens causing angular leaf spot (ALS), anthracnose, and ashy stem blight (Macrophomina phaseolina).
• Ten genotypes from accessions identified as variable for tannins were identified as having high levels of resistance to ashy stem blight.
• The sources of resistance to aphid- and whitefly-transmitted viruses identified by CIAT and collaborating NARIs showed effectiveness in controlling common mosaic, black root, and golden yellow mosaic in newly developed common bean cultivars.
• Lines with good drought tolerance and carrying the bc-3 gene for resistance to bean common mosaic necrosis virus (BCMNV) were recovered in phenotypes of small-black- or small-red-seeded varieties.
• Markers for two important genes for resistance to BGYMV were multiplexed in PCR amplification, thus greatly increasing MAS efficiency.
• Sources of resistance to the new viral disease affecting snap beans were successfully screened.
• Three new rust-resistant snap-bean lines were selected after 4 years of evaluation with farmers in Uganda, and distributed for regional evaluation.
• Four new snap-bean varieties with improved pod quality, resistance to rust, yield potential, and adaptation were selected in national performance trials with farmers, exporters, and a certification agency in Kenya.
• New breeding populations of snap runner bean segregating for adaptation to short-day tropical conditions were developed in eastern Africa.

Developed Germplasm with Resistance to the Pests Thrips palmi, Leafhopper, Pod Weevil, and Bruchids

• Resistance to the bean weevil (Acanthoscelides obtectus) was identified in Phaseolus vulgaris × P. acutifolius hybrids.
• Studies were completed on molecular markers for Thrips palmi resistance.
• Progress was made in developing molecular markers for resistance to the pod weevil (Apion godmani).

Developed More Nutritious Small-Seeded Bean Varieties

• Lines combining a moderate level of drought tolerance with 50% higher concentrations of iron were recovered. Although still deficient in terms of grain type and other agronomic traits, they will form the basis for another cycle of recurrent selection.
• A G × E study across CIAT’s research sites suggested that some factor associated with low pH leads to low iron concentrations in seeds.
• Two varieties (Gofta and Roba-1) showed high iron and zinc concentrations across sites and seasons.
• Significant interactions between genotypes, soil conditions, and P applications can be exploited to enhance iron and zinc concentrations in grain.
• Accessions of Phaseolus coccineus and P. polyanthus presented iron concentrations that were as much as 60% higher than checks, whereas zinc concentrations were only narrowly higher than the checks. Confirmation of greater advantages is needed to justify interspecific crosses to improve iron concentrations.
• New bean lines with high iron and zinc concentrations were identified in eastern Africa and evaluated for agronomic traits by more than 20 farmers.
  

Output 2: Improved, Large-Seeded, Bean Germplasm that is Resistant to Major Biotic and Abiotic Stresses and has Greater Nutritional and Market Value

Developed Germplasm Resistant to Diseases

• Over 1000 populations of different generations (F₃ to F₆) in various market classes were selected during this reporting period.
• Several lines were selected from the nurseries for large red kidney and sugar bean market classes. These lines combined more than one attribute such as high yield, resistance to diseases (ALS and floury leaf spot or FLS), and tolerance of low soil fertility. They will be available for distribution to NARIs partners through SABRN.
• Four advanced lines (HGA 24, HGA 25, HGA 26, and HGA 27) were identified as combining resistance to rust, common bacterial blight (CBB), anthracnose, and ALS.
• The recessive bc-3 gene is being successfully incorporated into climbing bean genotypes to control the increasing incidence of bean common mosaic in the South American highlands. This gene confers total resistance to the causal viruses (BCMV and BCMNV), and facilitates the selection of virus-resistant common bean genotypes possessing seed colors that exhibit genetic linkage problems (e.g., cranberry and red-seeded types).
• Several common bean genotypes possessing resistance to bean leaf crumple virus, a begomovirus transmitted by the whitefly Bemisia tabaci, were identified in field screening plots planted in Valle del Cauca (Colombia). The resistance sources identified are already present in many advanced common bean lines.
• More than 39 resistant and potential parental materials were evaluated under greenhouse conditions against nine isolates representing six Pythium species pathogenic to beans in eastern Africa. Thirty materials remained resistant.
• Over 500 F₂-derived F₅ lines and populations from simple, double, and back crosses were selected for Pythium and ALS resistance.
• Marker-assisted selection for BCMV resistance in Andean bush and climbing beans continued this year, with wide application of the SCAR markers ROC11 for the bc-3 gene and SW13 for the I gene. This work was expanded to include the collaboration of additional partners in the Andean Region: CORPOICA and Universidad Nacional–Bogotá (Colombia), and PROMPEX (Peru).
• We produced new heat-tolerant, BCMV-resistant climbing beans of the red-and-cream mottled Andean type. Peruvian varieties from the Alubia, Bayo, and Canario seed classes were also improved for BCMV resistance. Based on successes in marker-assisted selection, a new project will begin next year to incorporate BCMV resistance into eastern African varieties with partners from Kenya, Rwanda, and Uganda, including ISAR, KARI, NARO, the University of Nairobi, and the National University of Rwanda.
• Marker-assisted selection for anthracnose resistance genes was implemented in yellow, white, and red seeded climbing beans, using the SCAR markers SAS13 for the Co-4² gene and SAB3 for the Co-5 gene. The SAB3 marker was found to work well under a range of PCR conditions, and the amplification of the SAS13 marker was improved. The anthracnose resistance genes are being pyramided into lines with BCMV resistance and commercial seed type. This project is important for the breeding of Andean beans in both Africa and Latin America.

Developed Germplasm Resistant to Insects

• Marker-assisted selection of arcelin-derived resistance to bruchids was applied to advanced red-mottled breeding lines and showed promise for substituting the serology-based assays presently used for selection. These lines will be useful for Africa, the Andes, and the Caribbean, where Zabrotes weevils are prevalent in storage, causing severe losses.
• Tolerance of Empoasca kraemeri was confirmed in Andean bred lines.

Incorporated Broader Genetic Diversity into Beans

• Selections were made for low P tolerance in red-and-cream mottled Andean bush beans. Additionally, Colombian released varieties were compared for low P tolerance and yield index under low versus high P conditions.

Developed More Nutritious Large-Seeded Bean Varieties

• The high-iron NUA (Spanish code for “Andean nutrition”) breeding lines developed last year are being tested in on-farm trials with the collaboration of an NGO in the Departments of Nariño and Valle del Cauca (Colombia). Mineral analysis confirmed the high-iron status of four red-mottled sister lines, all well-adapted and derived from CAL 96. Notably, one line, NUA56, had an average iron content of 93 mg kg^–1 across three sites and as much as 112 mg kg^–1 in one site, one of the highest values for seed iron found so far. Other Andean red-seeded high-iron varieties were also identified. Low-iron sister lines were identified and are also well adapted. From this analysis, we identified potential genotypes to include in nutrition nurseries and hybridizations.
• At CIAT, we are analyzing G × E interactions in trials with RILs and finding good correlations across sites for iron content.
• Mineral analysis is also being used to identify the highest iron content in Cerinza-derived red and red mottled advanced breeding lines (BIF series) and among all Colombian released varieties.
• A crossing block for nutritional improvement of bush and climbing beans from Africa and Latin America has generated a total of 120 combinations, using high-iron landraces and the breeding lines described above.
• As part of the HarvestPlus Challenge Program, QTL mapping of nutritional traits has become important for increasing our understanding on breeding common bean for better mineral content. We are using a mix of traditional breeding, biochemistry, genetics, and genomics to dissect nutritional quality traits.
• We are also studying the inheritance of soluble and insoluble tannins, which are implicated as anti-nutrients in mineral absorption. We have conducted a QTL analysis of five segregating populations of common bean and analyzed a population for the seed darkening/nonoxidizing seed coat trait.
• Collaboration between CIAT and USDA–Houston is focusing on a basic mechanism, namely iron reductase, for mineral uptake in legumes, using common bean as a model for tropical legumes. Initital results suggest a relationship between a QTL for seed iron and another for iron reductase.
  

Output 3: Strategies Developed for Managing Diseases and Pests in Bean-Based Cropping Systems

Characterized and Monitored Pathogen and Insect Diversity

• The causal agents of three new diseases of common bean that have recently emerged in Colombia (Cabbage leaf curl virus (CaLcuV), Tomato yellow mosaic virus (ToYMV) and Bean leaf crumple) were identified.
• We showed that no host differential interaction existed in the common bacterial blight/common bean pathosystem, and that CBB pathogens may not have coevolved with common bean genepools.
• We developed a molecular assay for the specific detection and differentiation of CBB pathogens in bean seed, and a protocol for its application.
• We showed that the population structure of Colletotrichum lindemuthianum is changing, as evidenced by the resistance of previously susceptible varieties.
• We demonstrated that the varieties Widusa and Kaboon (Andean), and G 2333 (Mesoamerican) can be used to effectively manage all anthracnose races found in Colombia.
• The infection process of the ALS pathogen, Phaeoisariopsis griseola, was elucidated.
• The immune response of G 10474 to several pathotypes of P. griseola might be mediated through the production of an antifungal compound.
• A protocol was developed for the routine transformation of P. griseola, and the fungus was transformed to express the GFP protein. Some transformants lost their ability to infect bean (insertional mutagenesis).
• We characterized 134 Pythium isolates from areas affected by bean root rots in Kenya and Rwanda by sequencing the ITS-1 region of ribosomal DNA. The isolates were grouped into 22 species, of which nine were new additions. Distribution maps for Pythium species were developed.
• Important changes in the species composition of whitefly in targeted areas were detected. Varying levels of resistance or susceptibility to some of the insecticides commonly used to control whitefly were observed.

Characterized Genes for Disease and Insect Resistance

• At least two genes condition the resistance of G 19833 to four races of C. lindemuthianum. These genes are distinct from those in the Andean genotypes Michigan dark red kidney, Kaboon, and Perry Marrow, and may comprise a new Andean resistance locus.
• Two AFLP markers linked to ALS resistance in Mexico 54 and G 10474 were successfully converted to STS markers, and protocols for their use in MAS were developed. Similarly, the RAPD marker OPE4₇₀₉ linked to the ALS resistance gene in Mexico 54 was converted to a SCAR marker, and a protocol was developed.
• Two AFLP-derived SCAR markers (PF9 and PF11) were developed for G 10474 and Mexico 54.
• The allelic relationships of ALS resistance genes in Mexico 54 with G 10474, G 10909, G 10613, and Cornell 49242 were elucidated.
• Inheritance of resistance to Pythium root rot in five resistant genotypes was shown to be conditioned by single dominant genes. An allelism test, using the diallel mating scheme, revealed that the resistance is conditioned by the same resistance locus.
• Further progress was made on developing a SCAR marker for resistance to Apion godmani. Seven RAPD bands were cloned and five single-copy markers developed that mapped the same locations as the original RAPDs. In addition, a peroxidase fragment was cloned from one of the chromosomal regions with the most consistent Apion resistance gene. These markers provide potential assays for use in marker-assisted selection.
• Microsatellite and SCAR markers were evaluated for their usefulness in populations segregating for geminivirus resistance in a collaborative project with the University of Puerto Rico.

Developed Components for Integrated Pest Management

• Diffusion of technology activities within the DFID-funded project on Sustainable Management of Whiteflies was initiated.
• The second phase of the Tropical Whitefly IPM Project demonstrated the importance of adopting IPM measures to recover common bean production in whitefly-stricken regions.
• Three potential biocontrol agents for anthracnose were identified and tentatively classified as Paenibacillus polymyxa, Bacillus subtilus, and Gluconobacter species. The antimicrobial compound is possibly proteinaceous in nature. One bacterium also produces a heat-resistant compound.
• Preliminary results showed Calliandra calothyrsus to be the best source of green manure for controlling soil pathogens and increasing yields.
• Some of the Pythium species pathogenic to beans induced symptoms in sorghum, millets, field peas, and maize when these were grown as major crops in association with beans in southwestern Uganda.
• Some of the components useful in the integrated management of bean root rots effectively reduced root damage and increased yield parameters in sorghum, millets, field peas, and maize in bean-based cropping systems.
  

Output 4: Developed, Evaluated, and Widely Disseminated Improved Cultivars and Management Practices in Partnership with NARS, Regional Networks, NGOs, and Farmers

Supported Breeding Programs in NARS, Regional Networks, Farmers’ Associations, and CIALs, Using Germplasm and Technical Knowledge

• Many breeding line nurseries and germplasm were distributed to bean network partners from CIAT’s headquarters.
• Close collaboration between CIAT and breeding programs in the Andean Region continued with exchanges of researchers and germplasm. Training programs were developed for researchers from CORPOICA and the Universidad Nacional (Colombia), PROMPEX and INIA (Peru), and the Universidad Mayor de San Simón (Bolivia). One training project involved developing and confirming BCMV resistance in Peruvian dried beans, using marker-assisted selection for the first time in Peruvian bean improvement. Another project involved selection of BCMV and anthracnose resistance in climbing beans, using molecular markers.
• Lines bred for drought tolerance presented as much as 50% yield advantage over elite cultivars under drought conditions in Nicaragua, confirming that tolerance mechanisms selected in CIAT–Palmira are effective in Nicaragua.
• Some top-yielding cultivars across sites within SABRN (GCI-CAL-28-AR, AFR 708, CIM 9314, and CIM 9314-2) combine acceptable market type (red mottled), high yield potential, and resistance to ALS or FLS or both.
• This year, the national bean research program in the southern highlands of Tanzania released ‘Uyole 03’, derived from a CIAT-bred line DRK 124, and another line selected from crosses generated by NRI on a collaborative project with Tanzania. Various nurseries and germplasm were distributed to bean network partners.
• Four new small-red-seeded lines with tolerance of major diseases and higher yield potential (up to 40%) than commercial cultivars were selected in three countries in eastern Africa. Eight new small-red lines performed significantly better than the commercial checks in regional trials in two countries.
• Two new red mottled bean lines with higher yield potential than the best commercial checks and tolerant of major biotic stresses were identified in regional trials in four countries in eastern and central Africa. An elite nursery of new red mottled bean lines was constituted for validation with farmers and other end-users in eastern Africa.
• Five new red kidney bean lines showed outstanding performance in regional trials and were selected in four countries in eastern and central Africa. Thirteen new red kidney lines with better performance than the major commercial cultivar (Canadian Wonder) were selected in three countries.
• New releases of sugar bean became popular in southwestern Uganda as demand for sugar bean increases in eastern, central, and southern African markets.
• More than six new sugar bean lines with higher yield potential and combined resistance to ALS, anthracnose, and rust were identified in regional evaluations in eastern and central Africa.
• Sixty farmers from the Central and Eastern Highlands of Kenya, in collaboration with researchers, selected 20 red mottled, 20 red kidney, and 24 ALS and root rot resistant bean lines from a genetically diverse set of germplasm materials. More than 120 farmers started bulking seed from their new red mottled and red kidney bean lines. Farmers’ preference criteria for red mottled and red kidney bean cultivars were identified.
• Farmers and researchers selected, from segregating populations, 22 new climbing bean lines of major grain types preferred in the Central Highlands of Kenya and other areas in eastern and central Africa. New climbing bean lines with farmer-preferred traits were distributed for wider evaluation and seed bulking in more than 15 districts in Kenya.
• Twelve yellow, one sugar, and one medium yellow bean cultivars showed good adaptation to humid tropical lowlands (470 m above sea level).
• More than 14 agricultural NGOs, farmer associations, and community based organizations accelerated seed production and dissemination in lowland western Congo. Improved bean cultivars featured prominently in Kinshasa markets.
• Diffusion of improved bean cultivars to other countries in humid tropical lowlands of central and western Africa gained momentum.
• New bean lines of major market classes with high levels of tolerance of Al toxicity and acid low-fertility soils were identified. The Great Lakes Region proved to be a potential source of germplasm with tolerance of low soil fertility conditions.
• Five drought-tolerant bean lines were identified in regional trials in eastern Africa. A regional drought nursery was constituted and distributed to five drought-prone countries in eastern Africa.

Developed Sustainable Seed Systems for Wide Dissemination

• The number and diversity of partners for bean research and development significantly increased in the PABRA region, particularly in support of decentralized seed systems. Formalization of working relationships among partners was done through memoranda of understanding.
• Partners facilitated awareness, creation, knowledge, and skills enhancement for new or existing technologies by developing and disseminating diversified tools and approaches, including promotional and training materials, field days, radio talks, and agricultural shows.
• Through enhanced partnerships, a total of about 12,000 metric tonnes of assorted bean varieties were produced and made accessible to about 2.5 million farmers in the PABRA region.
• Eight case studies on seed relief to assist disaster-affected and chronically stressed communities were completed and are being compiled for publication.

Socioeconomic Activities

• Demand for beans is influenced by grain color, and prior knowledge about cooking times and taste of the different varieties.
• Market studies of the bean sector in Uganda and Kenya showed rising trends in the production and consumption of fresh and dried beans in Uganda but stable consumption in Kenya. Insufficient production in Kenya and demand in other countries offer opportunities for regional exports of dried beans from Uganda, while significant growth market opportunities exist for Kenya to export green beans to international markets.
• The bean market price at harvest in Malawi was primarily influenced by supply and demand.
• Researchers and extension agents who work with farmers in both NARIs and NGOs in the Andean Region should be aware of the profitability of bean production. Hence, we started a cost-benefit analysis of climbing versus bush beans in the Region’s production systems.
  

Output 5: Strengthened the Institutional, Organizational, and Collaborative Capacity of NARS and Subregional Networks in Africa and Latin America

Strengthened the Capacity of NARS by Increasing the Knowledge and Skills of Scientists and Staff from NARIs, NGOs, and Rural Service Providers

• In Latin America, two PhD candidates and one MSc candidates received their degrees and, in Africa, scientists working in the Bean Project received two PhD and three MSc degrees.
• In Africa, 408 persons attended courses or workshops for a total of 1497 person-days of training.
• Participatory plant breeding was strengthened regionally with a course in Kenya attended by 22 scientists from the region, including four from SABRN.
• Former IPM farmer groups in central Malawi have now taken up seed production as a business.
• Interaction between breeders in Africa and headquarters increased this year, with training in headquarters in marker-assisted selection and seed shipments being renewed from Africa to Colombia, thus leading to closer integration of the Latin American and African breeding programs.
• The assistant for the ECABREN program acquired skills in participatory monitoring and evaluation (PM&E) systems to support national bean programs.
• Biophysical scientists, NGOs partners, and technicians from northern Tanzania—28 in all—were exposed to PM&E organized by PABRA and ECABREN.
• ECABREN partners in Tanzania and Uganda acquired knowledge in seed systems and distribution channels.
• Two researchers, from ISABU and the Centre Technique Horticole d’Antananarivo, Madagascar, were trained by the ATDT/ISAR Project in the production of promotional materials.
• Farmers and researchers in northern Tanzania selected and named nine new marketable bean lines with tolerance of bean stem maggot and ALS after 4 years of participatory selection. Seed bulking by farmer groups and broader evaluation of new bean lines were initiated.
• A compilation on participatory breeding experiences across crops, countries, and regions of Africa was completed.

Collaborative Projects Developed and Executed with NARS and Regional Networks

• The Swiss Government extended its commitment to support the PABRA research network until 2007.
• A system of competitive grants under the auspices of ASARECA became operational and CIAT is participating in project development.
• A 6-year project under CIAT’s leadership was approved by the Canadian Government to improve Latin American crops for nutritional value.
• The CIAT bean team is participating in two CGIAR Challenge Programs.

Strengthened International Collaboration through Networks (Intra- and Inter-Network Collaboration) and/or Bilateral Relations

• Four Future Harvest Centers (CIAT, CIMMYT, ICRISAT, and IITA), together with SSSN, teamed up to sensitize various stakeholders on the sustainable ways of producing and distributing seed of open- and self-pollinated crops in Tanzania and Mozambique.
• Stakeholders selected from the production-to-consumption chain defined three bean products for ECABREN research portfolio. These were beans for food and health; canning beans for domestic and export markets; snap and dried beans (white and sugar beans) for domestic, regional, and international markets.