Agnaldo Donizete Ferreira de Carvalho

Verificação da adaptabilidade e estabilidade de populações de cenoura pelos métodos AMMI, GGE biplot e REML/BLUP

O objetivo desse estudo foi verificar a adaptabilidade e estabilidade de populacoes de cenoura diante de ambientes com cultivo orgânico e convencional e realizar a comparacao entre as metodologias estatisticas utilizadas. O trabalho foi desenvolvido em 2007 e 2008, em cinco locais. Em Sao Gotardo (MG); Irece (BA) e Gama (DF) foi realizado cultivo convencional e em PAD (DF) (Programa de Assentamento Dirigido do Distrito Federal) e Gama (DF) foi utilizado o sistema de cultivo orgânico. O delineamento experimental utilizado foi o de blocos ao acaso com tres repeticoes e parcelas de 1 m2. Foram avaliadas sete populacoes de cenoura do grupo Brasilia: 0912545, 0912532, 0912520, BRS Planalto, Esplanada, Brasilia e Alvorada. Aos cem dias apos a semeadura, foi determinada em cada parcela, em gramas, a massa das raizes com padrao comercial. Para a avaliacao da adaptabilidade e estabilidade foram aplicados os metodos AMMI, GGE Biplot e REML/BLUP. As analises AMMI e GGE Biplot foram bastante semelhantes na verificacao da adaptabilidade e estabilidade das populacoes de cenoura, e GGE Biplot agrupou de maneira mais clara os ambientes mais favoraveis e desfavoraveis. A analise REML/BLUP se destacou das demais e apesar de nao informar sobre o agrupamento de locais mais semelhantes, apresenta os resultados em funcao de valores genotipicos levando em consideracao os parâmetros de adaptabilidade e estabilidade. As populacoes com melhor adaptabilidade e estabilidade foram 0912532, BRS Planalto e 0912520.

Adaptabilidade e estabilidade de populações de cenoura

In the process of developing new cultivars, it is imperative to know the performance of carrot populations in final breeding phase for the possible environments to which they may be indicated; this can be verified testing the adaptability and stability. In this study the adaptability and stability of carrot genotypes from the Brasilia group were verified. The experiment was carried out during the 2007/2008, 2008/2009 and 2009/2010 crop years at five different places, three being in conventional growing at Sao Gotardo (Minas Gerais state), Irece (Bahia state) and Gama (Federal District), and two in organic growing at Managed Settlement Program of the Federal District (PAD-DF) and Gama. A randomized block design with three replications with 1 m2 plots was used. Four carrot genotypes from the Brasilia group: 0912532, 0912520, BRS Planalto and Brasilia were evaluated. 100 days following sowing, fresh mass of commercial root value was determined in grams, in each plot. Regarding adaptability and stability assessment, the REML/BLUP methodology was applied. BRS Planalto and 0912520 were the genotypes with better adaptability and stability; BRS Planalto was preeminent mainly in 2009-2010 crop years; and 0912520 was preeminent in 2007/2008 and 2008/2009. Brasilia had the worst performance in most places, but good performance and specific adaptability to Irece.

Resistência de populações de cenoura à queima-das-folhas com diferentes níveis de germoplasma tropical

A queima-das-folhas e responsavel por perdas significativas na producao de cenoura e a resistencia genetica e uma das formas mais eficientes de controle da doenca. Objetivou-se com este trabalho avaliar a resistencia de progenies de populacoes de cenoura a queima-das-folhas com diferentes niveis de germoplasma tropical. Foram avaliadas as populacoes 561, 586 e 587 e como testemunhas as cultivares comerciais, Juliana e BRS Planalto. Foi utilizado o delineamento de blocos casualizados, com duas repeticoes e parcela de 1,2 m2. A doenca ocorreu de forma natural no campo e foi avaliada a cada cinco dias, a partir dos 72 dias apos a semeadura. As populacoes 561, 586 e 587 e a cultivar BRS Planalto apresentaram severidades semelhantes e inferiores as cultivares Brasilia e Juliana, as quais nao diferiram entre si. Nao foram observadas diferencas significativas na producao comercial e total de raizes. Nas analises realizadas entre as progenies dentro de cada populacao e as testemunhas nao foram observadas diferencas na producao comercial e total de raizes. Com relacao a severidade, as progenies da populacao 561 e 586 e BRS Planalto nao diferiram entre si e apresentaram maiores niveis de resistencia que Brasilia e Juliana. Contudo, uma progenie da populacao 586 apresentou resistencia intermediaria. Dez de 15 progenies da populacao 587 apresentaram niveis de resistencia semelhantes a BRS Planalto, enquanto cinco apresentaram resistencia semelhante a Brasilia e Juliana. Esta maior variabilidade fenotipica indica seu potencial para a obtencao de ganho genetico para resistencia a queima-das-folhas. A producao de raizes comerciais e totais das populacoes 561 e 586 apresentaram correlacao negativa com a severidade da doenca. Tais resultados indicam que a resistencia a queima-das-folhas atribui-se, majoritariamente, ao germoplasma tropical, observado em maior quantidade na populacao 561, cerca de 87,5%.

Avaliação de cultivares de mamona em cruzamentos dialélicos parciais

Castor bean (Ricinus communis L.) is a very important crop in northeastern Brazil. Nowadays it became also important in other regions of Brazil, due to the Brazilian Biodiesel Program. The objective of the present work was to estimate general and specific combining ability for seed yield and agronomic traits in castor bean, in order to obtain a better understanding of the genetic control of these traits of breeding purposes. Two groups of cultivars were studied: Group 1, composed by five short stature cultivars, and Group 2, composed by five tall cultivars. The two groups were crossed according to a partial diallel design, giving rise to 25 hybrid evaluated in a 5 x 5 lattice design with four replications. Plots comprised of a nine meters single row spaced three meters apart (27 m2) with 10 plants. Seed yield (PR), days to flowering (DF), plant height (AP), height up to the primary raceme (AC), and length of primary raceme (TU) were evaluated. General combining ability (GCA) was significant for all traits within each group, while specific combining ability (SCA) was significant only for DF and TU. The GCA sum of squares was higher than SCA sum of squares for all traits, indicating that additive effect loci were more important than dominant effect loci. In both groups there are cultivars with favorable alleles for yield and agronomic traits.

Avaliação de progênies f2:4 e f4:6 de soja e perspectivas do uso de teste precoce para a produção de grãos

The objective of this work was to evaluate the perspectives of using early generation testing for grain yield in soybeans. The base material comprises a population derived from a two-way cross between lines 14 and 38, divergent for grain yield. One hundred progenies F2:4 and one hundred progenies F4:6 were derived from this population and evaluated in the 2006/07 growing season, using a lattice design with 4 replications, in two locations, at Piracicaba, SP. Plots consisted of 2 meter long rows spaced 0,5 meter apart, with 35 plants after thinning. The components of variance, coefficients of heritability on a plot mean basis and expected response to selection were estimated for grain yield from the joint analysis of variance, for F2:4 and F4:6 generations. Estimates of expected response to selection were about 60% higher in the F4:6 generation; however this superiority would probably be offset by the larger time to complete a cycle. General results indicate that early generation testing for grain yield in soybeans can be effective for moderate selection intensities.

Análise de fatores e regressão bissegmentada no estudo da adaptabilidade e estabilidade de cenoura

Analysis of factors and bissegmented regression in the study of adaptability and stability in carrots The objective of this study was to evaluate the stability and adaptability of eight genotypes of carrots (three cultivars and five populations) in 17 environments in the Northeast, Midwest, Southeast and Southof Brazil in the crop years 2009/10, 2010/11 and 2011/12. The experiments were grown from November to January of each year according to the farmers’ crop calendar. The plot was composed of an area with 1.0 m 2 in a randomized block design with three replications. The cultural practices were the same used by the farmers. At harvest, the marketable roots were quantified and the values converted to tha -1 . Analysis of variance was performed and after that, the factor analysis and bissegmented regression analysis to study the stability and adaptability . None of the genotypes showed wide adaptability. Factor analysis was able to cluster less than 50% of the evaluated environments. The ideal genotype was not found by regression analysis. The ‘BRS Planalto’ cultivar was the most adaptedby the bissegmented regression method while ‘Brasilia’ CNPH-589 and CNPH-600 were the most adapted by factor analysis. The results obtained by these methods demonstrate the difficulty of recommending a cultivar for all producing regions and regionalized programs should be initiated. The use of the two associated methods allows safer decisions concerning the behavior of genotypes of carrot.

Rendimento de tubérculos de clones elite de batata

O objetivo com o presente trabalho foi verificar o desempenho de sete clones elite de batata quanto a caracteres de rendimento de tuberculos, em comparacao com cultivares utilizadas em grande escala no Brasil. O experimento foi conduzido no campo experimental da Embrapa Produtos e Mercado, Canoinhas, SC. Foram avaliados sete clones elite desenvolvidos pelo Programa de Melhoramento Genetico de Batata da Embrapa e duas cultivares comerciais (Agata e Asterix), no cultivo de primavera de 2012. O delineamento experimental foi em blocos casualizados com quatro repeticoes e parcelas compostas de uma linha com 10 plantas. Aos 110 dias foram realizadas a colheita e avaliacoes de caracteres componentes do rendimento de tuberculos. Os dados foram submetidos a analise de variância, agrupamento de medias por Scott & Knott e correlacoes fenotipicas. Pode-se verificar que, com excecao de F22-08-01, todos os clones superaram as testemunhas quanto a caracteres de rendimento, com destaque para os clones F74-08-09 e F17-08-01. O rendimento total de tuberculos foi determinado principalmente pela massa media de tuberculos e pouco influenciado pelo numero total de tuberculos por planta, enquanto a massa de tuberculos comerciais foi determinada pelo numero de tuberculos comerciais e massa media de tuberculos.