Mapping of an andean gene for anthracnose resistance (Co-13) in common bean (Phaseolus vulgaris L.) Jalo Listras Pretas landrace

Abstract The common bean (Phaseolus vulgaris L.) andean Jalo Listras Pretas (JLP) landrace is an important source of resistance to anthracnose, which is a widespread disease caused by Colletotrichum lindemuthianum fungus. This common bean landrace carries Co-13 gene, one of the nine ones identified andean anthracnose resistance genes. The present study set out to identify molecular markers associated with Co-13 by evaluating the segregation patterns of 65 molecular markers, in a F 2 population derived from a cross between JLP (resistant to race 73 of C. lindemuthianum) and Cornell 49-242 (susceptible to race 73 of C. lindemuthianum) cultivars. Bulked segregant analysis was performed to identify which of these molecular markers was linked to Co-13 in JLP. Among the analyzed molecular markers, OV20 680 marker displayed a heteromorphic band of 680 bp linked to Co-13 resistant gene in coupling phase. Genotyping of the OV20 680 marker in F 2 population revealed a recombination of 1.7%, indicating a tight linkage between the OV20 680 marker and disease resistance gene (Co-13). In the recombinant inbred population BAT93/Jalo EEP558, OV20 680 segregated according to a 1:1 ratio and mapped on linkage group Pv03 at a distance of 1.8 cM from the Co-13 locus. Jalo Listras Pretas has shown to be an important source of resistance to anthracnose, possessing a new gene that should be valuable in breeding for anthracnose resistance in common bean. Identifying molecular markers linked to andean resistance genes may facilitate the development of cultivars with broad-based resistance to anthracnose by streamlining the process of combining andean and mesoamerican resistance genes

Evaluation of phenotypic stability of cassava clones by AMMI analysis in northwestern Paraná state

High yield stability and adaptability of storage root are highly desirable attributes of cassava clones. Theobjective of this study was therefore to evaluate the effect of the genotype x environment interaction (G x E) and the stability ofcassava clones developed at IAC. A subset of eight cassava genotypes was chosen in trials of storage root yield, arranged ina randomized complete block design with four replications, in two counties (Araruna and Maringá), in the northwesternregion of Paraná State, over five growing seasons (1997-2001). The G x E interaction was evaluated by joint varianceanalysis and stability and adaptability by AMMI analysis. The G x E interaction was significant (P<0.05) for storage rootyield. Results indicated AMMI analysis as an efficient tool for the evaluation of phenotypic adaptability and stability of cassavaclones and IAC 190 as the most promising clone

Genetic variability in traditional germplasm of common black beans in Santa Catarina State, Brazil

O objetivo deste trabalho foi avaliar a diversidade genética entre 45 cultivares de feijões tradicionais do grupo comercial preto, por meio de técnicas multivariadas baseadas em 11 caracteres morfoagronômicos e nutricionais. A distância generalizada de Mahalanobis fundamentou as técnicas de agrupamentos Tocher e UPGMA. Pelo método Tocher foram constituídos nove grupos. Foi detectada divergência genética entre as cultivares tradicionais e as testemunhas comerciais de feijão. A maior divergência foi observada entre as cultivares do grupo 7, em especial a cultivar CFE 22, que se apresentou mais divergente em relação às demais. Para compor programas de hibridação com os genótipos avaliados, sugerem-se cruzamentos entre as cultivares do grupo 2, em especial CFE 25, CFE 100 e FT Nobre, e as do grupo 7, em especial o acesso CFE 22. Essas cultivares se destacam por serem as mais divergentes entre si e por possuírem as melhores produtividades.The objective of this work was to evaluate the genetic diversity through eleven morphological, agronomic and nutritional characteristics, among 45 traditional cultivars of common black beans collected in Santa Catarina, Brazil. Genetic divergence was detected among traditional and commercial test cultivars. The generalized distance of Mahalanobis was the basis for Tocher and UPGMA clusters. By the Tocher method, nine groups were constituted and the greatest divergences were observed among the cultivars of the group 7, specially cultivar CFE 22. To compose breeding program with these groups of genotypes, it is suggested crossings among cultivars of the group 2, mainly with CFE 25, CFE 100, FT Nobre, and those of the group 7, specially cultivar CFE 22. These cultivars were the most divergent and productive ones

Genetic diversity and population structure of sweet cassava using simple sequence repeat (SSR) molecular markers

The objective of this study was to evaluate the population structure and genetic diversity among 66 sweet cassava (Manihot esculenta Crantz) traditional accessions collected in Maringa, Parana, Brazil, using microsatellite molecular markers. Population structure was analyzed by means of genetic distances and probabilistic models; allelic frequencies were used in order to assess the genetic diversity indexes (Ht , Ho, PIC, % polymorphism and number of alleles) for each locus studied. All evaluated loci were polymorphic and the average was highly heterozygote. The number of alleles per locus was low, suggesting that restrict genetic base is a consequence of accession exchange and a reduced number of ancestors in the population. The polymorphic information content (PIC) values showed considerable genetic diversity with a mean value of 0.5076 and peak of 0.5707 for locus GA140. The microsatellites markers revealed a wide genetic variability among the traditional accessions evaluated. Moreover, the sweet cassava populations were separated in two groups using two analytical methods (probabilistic and genetic distances). The most divergent accessions were BGM 17, BGM 20, BGM 51 and BGM 95. On the other hand, the most similar accessions were BGM 25, BGM 33, BGM 37, BGM 59 and BGM 214. Hybrid combinations formed by the most divergent combinations, especially between BGM 51 × BGM 296, BGM 95 × BGM 222 and BGM 20 × BGM 12, are the most promising ones for future sweet cassava breeding programsFil: Costa, Tiago Ribeiro Da. Universidade Estadual de Maringá. Departamento de Agronomia; BrasilFil: Vidigal Filho, Pedro Soares. Universidade Estadual de Maringá. Departamento de Agronomia; BrasilFil: Gonçalves Vidigal, Maria Celeste. Universidade Estadual de Maringá. Departamento de Agronomia; BrasilFil: Galván, Marta Zulema. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Fisiología Vegetal; ArgentinaFil: Lacanallo, Giselly Figueiredo. Universidade Estadual de Maringá. Departamento de Agronomia; BrasilFil: Silva, Luciano Ivano Da . Universidade Estadual de Maringá. Departamento de Agronomia; BrasilFil: Kvitschal, Marcus Vinicius. Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina; Brasi

ESTABILIDADE E ADAPTABILIDADE DE LINHAGENS E CULTIVARES DE FEIJÃO DO GRUPO CARIOCA

The common bean has been cultivated under different environmental conditions and technology levels. These environmental variations, linked to genotypes differences and interaction between genotypes and environments are the main reasons for those yield variations. The interaction genotype by environments has been a challenge for indication of cultivars and to select lines in breeding programs as well. The objective of this work was to evaluate the stability and adaptability of grain yield in 14 genotypes of carioca bean, studied in ten experiments of Cultivate Value and Using, carried out during agricultural years of 2000/01 and 2001/02. The experimental design utilized was the randomized blocks with four repetitions. The stability and adaptability were evaluated by non-parametric, bi-segmented and simple linear regression methodologies. The results demonstrated a concordance among methodologies for genotypes indications with exception for recommendation in unfavorable environments. The ideal genotype was not found by bi-segmented linear regression. The lines Vi 4899, Vi 0699 and Vi 4599 showed adaptability to general environments, and with LP 97-28 were indicated to unfavorable environments. In favorable environments Vi 4899, FT 97-155 and FTS Magnífico showed the better performances.O feijão é cultivado sob diferentes condições de ambientes e níveis tecnológicos. Estas diferenças aliadas às diferenças entre genótipos e à interação entre genótipos e ambientes são as principais responsáveis pelas variações nas produtividades. A interação genótipo por ambientes tem sido um desfio para a indicação de cultivares e para a seleção de linhagens nos programas de melhoramento. O objetivo deste trabalho foi avaliar a estabilidade e a adaptabilidade da produtividade de grãos de 14 genótipos de feijão carioca, avaliados em dez ensaios de Valor de Cultivo e Uso (VCU), conduzidos nos anos agrícolas 2000/01 e 2001/02. O delineamento utilizado foi de blocos casualizados, com quatro repetições. A estabilidade e a adaptabilidade foi avaliada por uma metodologia não paramétrica, e metodologias baseadas em regressão linear bissegmentada e linear simples. Os resultados demonstraram que houve concordância entre metodologias na indicação de genótipos, a exceção da recomendação para ambientes desfavoráveis. O genótipo ideal, considerando os parâmetros da regressão bissegmentada para ambientes favoráveis não foi encontrado. Entre os genótipos avaliados destacaram-se especialmente as linhagens Vi 4899, Vi 0699 e Vi 4599, apresentando, de forma geral, melhor produtividade, adaptabilidade e previsibilidade. As linhagens Vi 4899, Vi 0699 e Vi 4599 apresentaram adaptabilidade à ambientes gerais e também foram indicadas junto com LP 97-28 para ambientes desfavoráveis. Em ambientes favoráveis, Vi 4899, FT 97-155 e FTS Magnífico apresentaram as melhores performances

Identificação da variabilidade fenotípica numa população local de feijão-preto

The occurrence of variability offers the possibility to select the best genotypes. Based on thisprinciple, Epagri/Cepaf is carrying out several activities to rescue landraces of common beans. The aim of this study was to characterize the phenotypic variability of the landrace Azulão Caxambu and the effect of the selection of individual plants on the grain yield. The experiment was conducted at the experimental area of Epagri/Cepaf,in Chapecó, SC, during the 2004/05 agricultural season. Due to the phenotypic variability, intra-population plant breeding is suggested to increase the grain yield.A ocorrência de variabilidade abre a possibilidade de seleção dos melhores genótipos. Nesse sentido, a Epagri/Centro de Pesquisa para Agricultura Familiar – Cepaf – vem realizando trabalhos de resgate de variedades de feijão. O objetivo deste trabalho foi realizar estudos da variabilidade fenotípica da variedade local Azulão Caxambu e estudar o efeito da seleção de plantas individuais no incremento de produtividade. O experimento foi conduzido na área experimental da Epagri/Cepaf, em Chapecó, SC, no ano agrícola 2004/05. Em função da variabilidade fenotípica sugere-se o melhoramento intra-populacional para elevar a média de rendimento de grãos

Capacidade combinatória e heterose em cultivares de feijoeiro‑comum

The objective of this work was to determine the combining ability and heterosis, for productivity and yield components, in diallel hybrids derived from crossings between BRSMG‑Talismã, IPR Uirapuru,FT Soberano, BRS Campeiro, IAC Tybatã, and IPR Juriti parent cultivars. Fifteen hybrids were generated from diallel crosses, excluding reciprocals. The general and specific combining abilities were significant for plant height, number of pods per plant, number of seeds per plant, number of seeds per pod, 50‑seed weight, and grain yield, indicating the occurrence of both additive and nonadditive genetic effects. The best strategy to be adopted is the use of BRS Campeiro, FT Soberano and BRSMG‑Talismã cultivars in common bean breeding programs involving selection. The most promising combinations were 'IPR Uirapuru' x 'IAC Tybatã', 'IPR Uirapuru' x 'FT Soberano', 'BRS Campeiro' x 'IPR Juriti', and 'BRS Campeiro' x 'IAC Tybatã'. The parentsof these hybrids presented high estimates of specific combining abilities. Hybridization of cultivars belongingto distinguished commercial groups propitiates higher heterosis values in the segregant population.O objetivo deste trabalho foi determinar a capacidade combinatória e a heterose, quanto à produtividade de grãos e aos componentes de rendimento, em híbridos derivados dos cruzamentos dialélicos entre as cultivares BRSMG‑Talismã, IPR Uirapuru, FT Soberano, BRS Campeiro, IAC Tybatã, e IPR Juriti. Quinze híbridos foram gerados a partir dos cruzamentos dialélicos, sem os recíprocos. As capacidades de combinação geral e específica foram significativas em relação à altura de planta, ao número de vagens por planta, número de sementes por planta, número de sementes por vagem, peso médio de 50 sementes e à produção de grãos, e indicaram a ocorrência de efeitos aditivos e não aditivos. A melhor estratégia a ser adotada em programas de melhoramento que envolvam seleção é o uso das cultivares BRS Campeiro, FT Soberano e BRSMG‑Talismã. As combinações mais promissoras foram 'IPR Uirapuru' x 'IAC Tybatã', 'IPR Uirapuru' x 'FT Soberano', 'BRS Campeiro' x 'IPR Juriti' e 'BRS Campeiro' x 'IAC Tybatã'. Os parentais destes híbridos apresentaram elevadas estimativas de capacidade específica de combinação. A hibridização de cultivarespertencentes a grupos comerciais distintos propicia maiores valores de heterose

Review: Genetic diversity and population structure of cotton (Gossypium hirsutum L. race latifolium H.) using microsatellite markers

Cotton (Gossypium spp.) is the world’s leading natural fiber crop and is cultivated in diverse temperate and tropical areas. In this sense, molecular markers are important tools for polymorphism identification in genetic diversity analyses. The objective of this study was to evaluate genetic diversity and population structure in tetraploid cotton (Gossypium hirsutum L. race latifolium H.) by means of microsatellite markers. 43 cultivars and inbred lines from Africa, United States and Brazil were analyzed. From a total of 33 SSRs markers, 15 markers revealed 104 polymorphic SSR alleles. Four groups were identified applying different methods (the probabilistic method, Principal Coordinates Analysis and Neighbor Joining tree). American cultivars and inbred lines were included in group I; African cultivars in group II; and Brazilian cultivars in groups II, III and IV. The FST index indicated high genetic variability among the cultivars and inbred lines studied. In general, American cultivars were the most divergent compared to African and Brazilian ones. The dissimilarity index ranged from 0.06 to 0.90 and the lowest genetic divergence was observed between TAMCOT22 and TAM96WD-69s(L). Combination of American cultivars and inbred lines with African and Brazilian cultivars is recommended for obtaining superior segregant in order to improve yield.Key words: Dissimilarity index, Gossypium hirsutum L., polymorphism, SSRs markers

Genetic diversity and population structure of cotton (Gossypium hirsutum L. race latifolium H.) using microsatellite markers

Cotton (Gossypium spp.) is the world?s leading natural fiber crop and is cultivated in diverse temperate and tropical areas. The proper use of cotton genetic resources allows breeders to identify and select superior parents for breeding programs. In this sense, molecular markers are important tools for polymorphism identification in genetic diversity analyses. The objective of this study was to evaluate genetic diversity and population structure in tetraploid cotton (Gossypium hirsutum L. race latifolium H.) by means of microsatellite markers. 43 cultivars and inbred lines from Africa, United States and Brazil were analyzed. From a total of 33 SSRs markers, 15 markers revealed 104 polymorphic SSR alleles. Four groups were identified applying different methods (the probabilistic method, principal coordinates analysis and neighbor joining tree). American cultivars and inbred lines were included in group I; African cultivars in group II; and Brazilian cultivars in groups II, III and IV. The FST index indicated high genetic variability among the cultivars and inbred lines studied. In general, American cultivars were the most divergent in relation to African and Brazilian ones. The dissimilarity index ranged from 0.06 to 0.90 and the lowest genetic divergence was observed between TAMCOT22 and TAM96WD-69s(L). Combination of American cultivars and inbred lines with African and Brazilian cultivars is recommended to obtain superior transgressive segregants in order to improve yield in cotton breeding programs.Fil: Domingos Moiana, Leonel. No especifíca;Fil: Soares Vidigal Filho, Pedro. Universidade Estadual de Maringá; BrasilFil: Gonçalves Vidigal, Maria Celeste. Universidade Estadual de Maringá; BrasilFil: Figueiredo Lacanallo, Giselly. Universidade Estadual de Maringá; BrasilFil: Galván, Marta Zulema. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: de Carvalho, Luiz Paulo. No especifíca;Fil: Maleia, Manuel Pedro. No especifíca;Fil: Maritza Pacheco, Cynthia. Universidade Estadual de Maringá; BrasilFil: Ribeiro, Tiago. Universidade Estadual de Maringá; BrasilFil: Zeni Neto, Hugo. Universidade Estadual de Maringá; BrasilFil: Kelly Coimbra, Gislayne. Universidade Estadual de Maringá; Brasi

Adaptability and stability of popcorn cultivars in the central-south of Brazil

Este trabalho teve como objetivo estudar a adaptabilidade e estabilidade de cultivares de milho-pipoca avaliadas pela Embrapa-Centro Nacional de Pesquisa de Milho e Sorgo, no ano agrícola 1991/92. Foram avaliadas 15 cultivares em 19 locais quanto à produtividade, e em 15 locais quanto ao índice de capacidade de expansão (ICE) na região centro-sul do Brasil. As cultivares GO 100P, MF 1001, Pirapoca-Amarela, Pirapoca-Branca e Colorado Pop 1, foram mais promissoras, pois apresentaram boas médias de produtividade (1.700 a 2.100 kg/ha de grãos) e razoáveis ICE (17 a 21 mL/mL). Quanto à variável produtividade, as cultivares Pirapoca-Amarela e Colorado Pop 1 apresentaram-se adaptadas a ambientes favoráveis, e foram estáveis. As cultivares MF 1001, Pirapoca-Branca e GO 100P, demonstraram capacidade satisfatória no aproveitamento dos estímulos ambientais, e foram estáveis. Todas foram estáveis em relação ao ICE, e as cultivares MF 1001, Colorado Pop 1, Pirapoca-Amarela e Pirapoca-Branca demonstraram capacidade satisfatória no aproveitamento dos estímulos ambientais. A cultivar GO 100P foi melhor adaptada para ambientes favoráveis.The purpose of this work was to study the adaptability and stability of popcorn cultivars evaluated by Embrapa-Centro Nacional de Pesquisa de Milho e Sorgo in the year 1991/92. Fifteen cultivars were evaluated for yield, in 19 environments, and for popping expansion, in 15 environments, at the central-south of Brazil. The cultivars GO 100P, MF 1001, Pirapoca-Amarela, Pirapoca-Branca and Colorado Pop 1 were more promising, showing higher grain yield average (1,700 to 2,100 kg/ha) and reasonable popping expansion (17 to 21 mL/mL). In relation to yield, Pirapoca-Amarela and Colorado Pop 1 cultivars were more adapted to favorable environments, and were stable. The MF 1001, Pirapoca-Branca and GO 100P showed to be responsive to the environmental stimulus, and were stable. In relation to popping expansion, all the cultivars were stable, and MF 1001, Colorado Pop 1, Pirapoca-Amarela e Pirapoca-Branca cultivars showed to be responsive to the environmental stimulus. GO 100P cultivar was adapted to favorable environments