18 research outputs found
Half a century of studying adaptability and stability in maize and soybean in Brazil
The study of adaptability and stability underlies the cultivar recommendation process for all crops. There is a considerable number of statistical methods available for this purpose, but little is known about their actual adoption by the Brazilian scientific community. The objective of this study was to carry out a systematic review of the scientific literature on the adaptability and stability methods used in maize and soybean in Brazil from scientific articles published between 1970 and 2017 in Brazilian journals. Article searches were carried out in journals indexed through the SciELO database. The articles were classified according to the year of publication and the adaptability and stability methods used. We also evaluated the pattern of association between methods. We found 113 articles on adaptability and stability in maize and soybean, in which 21 methods were listed. The most commonly used method was the Eberhart and Russell methodology. The Cruz, Torres, and Vencovsky along with the AMMI methods were also widely used. The number of articles using most methods decreased in the current decade, except for the GGE Biplot, MHPRVG, and Centroid methods. In studies with more than one method, the methods were more likely to be used together with the Eberhart and Russell methodology. Adaptability and stability in maize and soybean have been widely studied over the last several decades in Brazil, although the number of publications on this subject has decreased over this time period
Comparative study between phenotypic and genomic analyses aimed at choosing parents for hybridization purposes
The development of superior cultivars involves parents with superiority for the traits of interest and wide genetic variability. Efficient plant breeding and selection strategies that allow for the identification of superior genotypes are essential in breeding programs. This work aims to carry out a comparative study between several strategies for choosing parents, for hybridization purposes, based on phenotypic analysis and molecular information. To obtain the phenotypic and genotypic information of the parents, data simulation was used. For genotyping, 2000 single nucleotide polymorphism markers were used, and from all possible gametes to be formed (22000), 5000 were randomly sampled to form each of the 100 individuals of the population of recombinant inbred strains. To obtain the phenotypic information, five characteristics with different levels of complexity were simulated. The comparative study was carried out using data referring to simulated genotypic values of hybrids and parents. Then, aiming to choose the parents destined for hybridization, different traditional selection strategies based on phenotypic analysis and the genome-wide selection methodology were approached. The genomic information resulted in the choice of the best lines and in obtaining superior hybrids when compared with traditional methodologies. The inclusion of the genomic genetic values of the parents in determining the crosses to be carried out increases the probability of generating phenotypically superior hybrids. Thus, the traditional methods of choosing parents for hybridization purposes are effective, but when incorporating the information from genome-wide selection, the choice of parents provides superior and promising results
Direct, indirect and simultaneous selection as strategies for alfalfa breeding on forage yield and nutritive value
Alfalfa breeding aimed at trait improvement for livestock feed takes longer periods of time, if compared to many other crops. Therefore, better selection methods are necessary for the success of alfalfa breeding programs. Although knowing about selection methods is quite important, there is a notable lack of information, as regards successful solutions. This study aimed to use direct, indirect and simultaneous selection methods for selecting alfalfa cultivars, based on yield traits and nutritive value. The evaluated traits were subdivided into two groups: forage yield and nutritive value. Selection gains were estimated by direct, indirect and simultaneous selection for each group, considering the selection of the 25 % best cultivars. Direct and indirect selections among genotype averages are not efficient to provide the desirable responses to the whole set of traits. The results for simultaneous selection, using the Tai index, provided a more balanced gain distribution to the set of traits in all cuts. The simultaneous selection allowed the identification of the 5681 and Verdor cultivars in the first cut, as well as ProINTA Patricia in the second cut, as superior in the two groups of evaluated traits
Redes neurais artificiais comparadas com modelos lineares generalizados sob o enfoque bayesiano para predição de resistência à ferrugem em café arábica
The objective of this work was to evaluate the use of artificial neural networks in comparison with Bayesian generalized linear regression to predict leaf rust resistance in Arabica coffee (Coffea arabica). This study used 245 individuals of a F2 population derived from the self-fertilization of the F1 H511-1 hybrid, resulting from a crossing between the susceptible cultivar Catuaí Amarelo IAC 64 (UFV 2148-57) and the resistant parent Híbrido de Timor (UFV 443-03). The 245 individuals were genotyped with 137 markers. Artificial neural networks and Bayesian generalized linear regression analyses were performed. The artificial neural networks were able to identify four important markers belonging to linkage groups that have been recently mapped, while the Bayesian generalized model identified only two markers belonging to these groups. Lower prediction error rates (1.60%) were observed for predicting leaf rust resistance in Arabica coffee when artificial neural networks were used instead of Bayesian generalized linear regression (2.4%). The results showed that artificial neural networks are a promising approach for predicting leaf rust resistance in Arabica coffee.O objetivo deste trabalho foi avaliar o uso de redes neurais artificiais em comparação à modelagem por meio de modelos lineares generalizados na predição de resistência à ferrugem em café arábica (Coffea arabica). Foram utilizados 245 indivíduos provenientes de uma população F2, oriundos da autofecundação do híbrido F1 H511-1, resultante do cruzamento da cultivar suscetível Catuaí Amarelo IAC 64 (UFV 2148-57) e do genitor resistente Híbrido de Timor (UFV 443-03). Os 245 indivíduos foram genotipados com 137 marcadores. Realizaram-se análises com redes neurais artificiais e com modelos lineares generalizados sob o enfoque bayesiano. As redes neurais identificaram quatro marcadores importantes pertencentes a grupos de ligação que foram recentemente mapeados, enquanto o modelo generalizado bayesiano identificou somente dois marcadores pertencentes a esses grupos. Foram observadas taxas de erro de predição inferiores (1,60%) para predizer a resistência à ferrugem em café arábica, quando foram utilizadas as redes neurais artificiais em vez de modelos lineares generalizados sob o enfoque bayesiano (2,4%). Os resultados mostraram que as redes neurais artificiais são uma abordagem promissora para predizer a resistência à ferrugem em café arábica
Principal Component and Biplot Analysis in the Agro-industrial Characteristics of Anacardium spp.
The cajuí Anacardium spp., which is similar to the caju Anacardium Ocidentale L., is a species adapted to edaphic-climatic conditions of the biome Cerratinga (Cerrado e Caatinga). Its fruit is composed of one swollen stalk (pedicel) which is formed by nutritional reserves rich in vitamin C and drupe (cashew nut). It is also rich in protein and lipids, but with smaller size. This paper focuses on investigating the applicability of the biplot graphical analysis in the process of selective breeding of cajuí population. The cajuí working European Scientific Journal October 2019 edition Vol.15, No.30 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 22 population in Embrapa Meio Norte comprises of 11 genotypes collected in areas of natural habitat in the state of Piaui. The experiment was designed in randomized complete blocks with two plants per plot and four replications. A graphical analysis (biplot) was used to study the relationships between variables and behavior of the experimental genotypes. This was implemented to principal component analysis based on singular value decomposition biplot. The total variable weight can be predicted from length of peduncle, basal and apical diameter of peduncle, and variables of easy mensuration. Genotypes M40A, M23, M14, and M17 are similar to each other and they have high amounts of brown, apical and basal diameter of the peduncle, total weight, and peduncle length. They are considered as candidates selected for consumption in natura and industrial processing. The graphical analysis (biplot) showed robustness in the presentation of relationships between variables considered and the indication of the selection candidate genotypes in the population studied
Artificial neural networks compared with Bayesian generalized linear regression for leaf rust resistance prediction in Arabica coffee
Characterization of the common bean root system and its use in genetic breeding
Atualmente, no Brasil, como forma de minimizar problemas relacionados à deficiência de fósforo no solo, são utilizados corretivos e fertilizantes, adequando o solo à planta. Considerando que as reservas globais de fósforo inorgânico estão se esgotando, a estratégia seria adequar a planta ao fósforo contido no solo. Para isso é necessário detectar e explorar o uso das diferenças genotípicas, especialmente as relacionadas à arquitetura das raízes. Com esse intuito, 56 genótipos de feijão foram avaliados e caracterizados fenotipicamente quanto ao sistema radical. Posteriormente, dois genótipos contrastantes quanto à arquitetura de raízes foram utilizados na composição de uma multilinha, visando verificar se a mistura de genótipos de feijoeiro (multilinha) com características contrastantes de arquitetura de raízes basais beneficia a produtividade de grãos. O primeiro experimento constou da semeadura dos 56 genótipos em campo, utilizando-se o delineamento em blocos ao acaso. Foram avaliados os caracteres produtividade e massa de 1.000 grãos. Sementes desse experimento foram germinadas em papel de germinação e colocadas em cubas de vidro com solução nutritiva de sulfato de cálcio, usando-se o delineamento em blocos ao acaso. Foram avaliados os seguintes caracteres: número de verticilos, número de raízes basais, nota de pelos nas raízes basais, ângulo médio das raízes basais e nota de pelos na raiz principal. Os dados foram submetidos à análise de diversidade genética, tomando-se como base o método de Tocher e de variáveis canônicas. O segundo experimento constou da avaliação dos genótipos Diamante Negro (raízes basais superficiais), Vi-10-2-1 (raízes basais profundas) e da multilinha (Diamante Negro + Vi-10-2-1), em ambientes contrastantes quanto à disponibilidade de fósforo no solo (plantios direto e convencional e adubado e não adubado), compondo um fatorial 3 x 2 x 2, no delineamento em blocos ao acaso. Nesse experimento foram avaliados: massa da parte aérea seca (MPAS), teor de fósforo (TP), conteúdo de fósforo (CP), produtividade (PROD) e os componentes de produção número de vagens por planta (NV), número de sementes por vagem e massa de 100 grãos (MCG). No primeiro experimento, com base na análise de diversidade, detectou-se que o germoplasma de feijão avaliado apresenta ampla variabilidade genética para características de raiz. Pela técnica de variáveis canônicas, o número de raízes basais, nota de pelos na raiz primária e ângulo médio das raízes basais foram, nesta ordem, as de menor importância para o grupo gênico mesoamericano; no caso do grupo gênico andino, o ângulo médio das raízes basais e nota de pelos na raiz basal foram os de menor importância. Esses resultados, comparados aos obtidos pela metodologia de Singh (1981), indicaram que há redundância entre número de raízes basais e número de verticilos e entre nota de pelos na raiz primária e nas raízes basais. Quando se repetiu o procedimento de agrupamento por Tocher, após a exclusão das variáveis menos importantes pela técnica de variáveis canônicas, obtiveram-se agrupamentos dos genótipos diferentes, indicando que, apesar de essas variáveis serem identificadas como as de menor contribuição para a diversidade dos genótipos, elas ainda contribuem com uma fração importante para discriminá-los. No segundo experimento, quando adubado, a multilinha (DN + Vi) superou a cultivar Vi 10-2-1 e se equiparou à cultivar Diamante Negro em produtividade de grãos, tanto no plantio direto quanto no convencional. Nesse caso, o pior comportamento foi do Vi, que por sinal apresenta raízes basais profundas. Em plantio convencional, não adubado, a multilinha foi bem superior às linhas puras, chegando a produzir 20% a mais que o DN e 40% a mais que o Vi.Currently in Brazil, in order to minimize problems related to deficiency of phosphorus from the soil, are used fertilizers to adjust the soil to the plant requirement. Whereas the global reserves of inorganic phosphorus are running out, the strategy would be to adapt the plant to the phosphorus contained in the soil. For this we need detect and explore the use of genotypic differences, especially those related to the root architecture. For this purpose, 56 bean genotypes were evaluated and characterized phenotypically on the root system. Subsequently, two different genotypes on the root architecture were used in the composition of a multi-line to see the mixture of bean genotypes (multiline) with contrasting characteristics of basal root architecture increases grain yield. The first experiment consisted of 56 genotypes that were seeded in the field, using a randomized block design. We assessed the following characters: productivity and mass of 1000 seeds. Seeds of this experiment were germinated in germination paper and placed in glass tanks with nutrient solution of calcium sulphate, using a randomized complete block design. The following characters were evaluated: number of whorls, number of basal roots, root hairs note in basal roots, average angle of basal roots and root hairs note at the tap root. The dates were subjected to analysis of genetic diversity, based on the Torcher method and Canonical Variables. In the second experiment, the genotypes diamante negro (shallow basal roots), Vi-10-2-1 (deep basal roots) and multiline (Diamante Negro + Vi-10-2-1) were evaluated in soil with environments different phosphorus availability under no-tillage systems and conventional (with fertilized and not fertilized), forming a 3x2x2 factorial, in randomized block design. In this experiment were evaluated: shoot dry weight, phosphorus content, phosphorus content , productivity and yield components: number of pods per plant, number of seeds per pod and 100-grain mass. In the first experiment, based on the analysis of diversity, it was observed that the bean germplasm has wide genetic variability for root traits. By methodology of canonical variables, the number of basal roots, note the taproot hairs, average angle of basal roots were in this order, the less important to the mesoamerican gene pool group. For the andean gene pool group the average angle of basal roots of and note the basal roots hairs were less important. These results compared with those obtained by the method of Singh (1981) indicate that there is redundancy between the number of basal roots and number of whorls and root hairs note from the taproot and basal roots. When we repeated the clustering procedure by Tocher, after exclusion of less important variables by the technique of canonical variables, we obtained clusters of different genotypes indicating that although these variables were identified as those with lower contribution to the diversity of genotypes, they still contribute a significant fraction to discriminate against them. In the second experiment, when fertilized, the multiline (DN + Vi) overcame the Vi 10-2-1 cultivar and the diamante negro cultivar matched in grain yield in both the under no-tillage systems and conventional. In this case, was the worst performance of Vi 10-2-1 genotype, which has deep basal roots. In conventional tillage, not fertilized, the multiline was well above the pure lines, up to produce 20% more than the DN and 40% more than Vi 10-2-1.Conselho Nacional de Desenvolvimento Científico e Tecnológic
Genetic divergence between passion fruit hybrids and reciprocals based on seedling emergence and vigor
Characteristics related to seed quality have been rarely used in studies on the genetic diversity of passion fruit. The purpose of this study was to evaluate the genetic diversity between progenies constituted by hybrids and reciprocals, based on seed emergence and vigor traits. On the 28th day, emergence percentage, emergence speed index, shoot length, root length and total length of seedling; dry weight, number of normal seedlings and 100-seed weight were evaluated in a completely randomized design experiment with 20 progenies (hybrids and reciprocals) and four replications (50 seeds). Genetic diversity was determined using the Tocher optimization clustering methods and the unweighted pair group method, based on the Mahalanobis distance, as well as evaluating the relative contribution of the traits to genetic divergence and the correlation network, according to the relations between groups of quality, length and mass variables. The most contributing variable to genetic divergence was the total length of seedlings, the reciprocal effect did not present a consistent pattern in the studied hybrid combinations.Características relacionadas à qualidade de sementes tem sido pouco utilizada em estudos sobre diversidade genética em maracujazeiro. O objetivo deste estudo foi avaliar a diversidade genética entre progênies constituídas por híbridos e recíprocos com base em características de emergência e vigor das sementes. Foram avaliadas: porcentagem de emergência, índice de velocidade de emergência, comprimento total da plântula, comprimento da parte aérea, comprimento da raiz primária, massa seca de parte aérea, número de plântulas normais e peso de 100 sementes. O experimento foi em delineamento inteiramente casualizado, com 20 progênies (híbridos e recíprocos) e quatro repetições de 50 sementes. A diversidade genética foi determinada através dos métodos de agrupamento de otimização de Tocher e da ligação média não ponderada entre grupos, baseada na distância de Mahalanobis, além de avaliar a contribuição relativa dos caracteres para a divergência genética e a rede de correlações de acordo com as relações entre os grupos de variável qualidade, comprimento e massa. A variável que mais contribuiu para a divergência genética foi o comprimento total da plântula, sendo que o efeito recíproco não apresentou padrão consistente nas combinações híbridas estudadas
Genetic divergence between passion fruit hybrids and reciprocals based on seedling emergence and vigor
Abstract: Characteristics related to seed quality have been rarely used in studies on the genetic diversity of passion fruit. The purpose of this study was to evaluate the genetic diversity between progenies constituted by hybrids and reciprocals, based on seed emergence and vigor traits. On the 28th day, emergence percentage, emergence speed index, shoot length, root length and total length of seedling; dry weight, number of normal seedlings and 100-seed weight were evaluated in a completely randomized design experiment with 20 progenies (hybrids and reciprocals) and four replications (50 seeds). Genetic diversity was determined using the Tocher optimization clustering methods and the unweighted pair group method, based on the Mahalanobis distance, as well as evaluating the relative contribution of the traits to genetic divergence and the correlation network, according to the relations between groups of quality, length and mass variables. The most contributing variable to genetic divergence was the total length of seedlings, the reciprocal effect did not present a consistent pattern in the studied hybrid combinations