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mon bean growers must use corrective soil amendments such as lime (Fageria et al., 1995; Westermann, 1992), Soil mineral deficiencies or toxicities adversely affect common bean manure or composted manure (Tarkalson et al., 1998), (Phaseolus vulgaris L.) production worldwide. Cultivars tolerant to low soil fertility (LF) should support sustainable farming systems and and fertilizers rich in macro-and micronutrients such reduce production costs and farmers' dependence on fertilizers. Our as N, P, B, Fe and/or Zn (Edji et al., 1975; Henson and objective was to identify LF tolerant landraces and improved common Bliss, 1991). Identification and use of cultivars tolerant bean genotypes. We systematically screened 5000 to 5500 landraces to mineral deficiencies and/or toxicities are essential for and improved genotypes for LF tolerance at Popayá n and Quilichao, reducing production costs and dependence of farmers Colombia, between 1978 and 1998. Mean LF intensity index across on soil amendment inputs. locations for seed yield ranged from 0.35 to 0.68. Average seed yield Greenhouse, growth chamber, and/or field screening reduction over five cropping seasons was 53%. Seed yield, biomass, methods have been used to identify crop germplasm and HI were positively associated in LF and high soil fertility (HF). tolerant to mineral deficiency or toxicity (Duncan et al., LF tolerance was identified in eight landraces and 14 improved geno-1983). Large genotypic differences among crops also types. All landraces were from Middle America (MA), belonging to common bean races Durango, Jalisco, and Mesoamerica. All improved have been reported (Dwivedi, 1996; Fageria et al., 1995). genotypes except one (A 36) also possessed characteristics of and Within-species variation in common bean for P (Whiinvolved one or more LF tolerant MA landraces in their pedigree. teaker et al., 1976) and Zn deficiency and response There was considerable variation for seed, plant, and maturity charac-(Westermann and Singh, 2000) and Al tolerance (Foy teristics among LF tolerant genotypes. In LF, mean seed yield for et al., 1972; Noble et al., 1985) have been documented. landraces ranged from 856 kg ha Ϫ1 for 'Apetito' to 332 kg ha Ϫ1 for At the Centro Internacional de Agricultura Tropical G 19833. Among improved genotypes, A 774 had the highest (948 (CIAT), Cali, Colombia, extensive research was conkg ha Ϫ1) and CAP 4 the lowest (651 kg ha Ϫ1) seed yield. Reduction ducted on N 2 fixation (Graham, 1981) and tolerance of in seed yield due to LF ranged from 31% for A 36 to 63% for CAP 4.

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Nutrientes minerais (Fe, Ca, Cu, Mn, Mg e Zn) e compostos fenólicos (fenóis totais e taninos) de dezesseis variedades de feijões, cultivados sob condições controladas, foram quantificados. Os dados obtidos das determinações químicas e das produtividades dos feijões foram avaliados empregando métodos multivariados: análise de componentes principais, análise de agrupamentos e análise de correlação canônica. Três grupos de cultivares foram reconhecidos e tanto os minerais Fe, Zn, Cu e Mn quanto os rendimentos dos feijões foram os principais responsáveis por esta discriminação. Variedades promissoras de feijões para programas de biofortificação ou uso direto em alimentos fortificados foram identificadas principalmente no grupo I, no qual os cultivares Aporé (Fe e Mg), Bambuí (Zn) e Valente (Fe e Cu) conciliaram boa produtividade e altos níveis de minerais. O uso da análise de correlação canônica possibilitou detectar relações significativas entre produtividade dos feijões, taninos e os metais Mg, Zn e Mn.The contents of mineral nutrients (Fe, Ca, Cu, Mn, Mg, and Zn) and phenolic compounds (total phenols and tannins) of sixteen bean cultivars grown under controlled conditions have been quantified. Data obtained from chemical determinations and bean yields were evaluated by multivariate methods, principal components, hierarchical cluster and canonical correlation analysis. Three groups of cultivars were recognized and mineral nutrients Fe, Zn, Cu, and Mn as well as bean yields were the most relevant factors for their discrimination. Potential bean varieties for biofortification programs or direct use in fortified food were identified mainly in cluster I, in which a number of cultivars conciliate good yields and high mineral contents, such as Aporé (Fe and Mg), Bambuí (Zn), and Valente (Fe and Cu). The use of canonical correlation analysis allowed for the detection of significant relationships between bean yield, tannins, and Mg, Zn, and Mn metals. Keywords: Phaseolus vulgaris, mineral nutrients, phenolic compounds, multivariate analysis IntroductionThe common bean (Phaseolus vulgaris L.) is one of the most important sources of proteins, calories, B-complex vitamins, and minerals in Latin America. In Brazil, the bean consumption per capita is about 17 kg/year, 1 which makes this legume essential against severe iron deficiency anaemia, a critical public health problem in South and Central America, affecting as many as 25% of pregnant women and 40% of children under 5 years old. 2In developing countries, beans are the best non-meat source of iron, providing 23-30% of daily recommended levels in a single serving.1 Common beans also contribute to human nutrition with other important minerals, such as Zn, Ca, Mg, Mn and Cu. 3 Mineral contents in bean grains can vary largely depending on the varieties, 4,5 and on environmental factors, such as soil composition.6 Taking into account the nutritional value of beans, another important aspect needs to be considered: the presence of anti-nutritional components, such as tann...