ABSTRACT
In forage-plants breeding, the selection of superior genotypes has been undertaken through successive harvests in previously established intervals. However, this process involves many steps, the evaluation of many traits, and a great spending with costs and labor. Thus the estimate of the repeatability is essential in improvement of perennials, it allows predicting genotypic value of the individual, the minimum number of evaluations in the selection of genotypes and minimizes resources and time in the selection of promising individuals. The objective of this study was to estimate the repeatability coefficient for morphological traits in elephant grass and determine the number of evaluations needed for phenotypic selection more efficient. The experimental randomized block design with 53 genotypes and two replications. The repeatability coefficients were estimated for variables plant height, number of tillers, stem diameter and dry matter yield, using the methods of Anova, Principal Components and Structural Analysis. We observed significant differences between genotypes (P <0.01) for all variables. The main components provide larger estimates of repeatability when compared to other methods. Estimates of the repeatability coefficients are of high magnitude average for the variables plant height (0.44) number of tillers (0.44) and stem diameter (0.63) and low magnitude for dry matter production (0.27). The Principal Components method requires five, five, two and eleven measurements for plant height, number of tillers, stem diameter and dry matter yield, respectively, with 80% reliability.
No melhoramento de plantas forrageiras, a seleção de genótipos superiores tem sido realizada mediante a realização de cortes sucessivos em intervalos previamente estabelecidos. Entretanto este processo envolve muitas etapas, avaliação de muitos caracteres e um grande dispêndio de custos e mão-de-obra. Assim, a estimativa da repetibilidade é essencial no melhoramento de plantas perenes, pois permite predizer o valor genotípico do indivíduo, o número mínimo de avaliações na seleção de genótipos e minimiza recursos e tempo na seleção de indivíduos promissores. O objetivo deste trabalho foi obter estimativas do coeficiente de repetibilidade para caracteres morfoagronômicos em capim-elefante e determinar o número de avaliações necessárias para seleção fenotípica com maior eficiência. Utilizou-se delineamento experimental de blocos casualizados com 53 genótipos e duas repetições. Foram estimados os coeficientes de repetibilidade para as variáveis altura de plantas (ALT), número de perfilhos (NP), diâmetro de colmo (DC) e produtividade de matéria seca (PMS), utilizando-se os métodos da Anova, Componentes principais e Análise estrutural. Observaram-se diferenças significativas entre os genótipos (p<0,01) para todas as variáveis avaliadas. Os componentes principais proporcionam maiores estimativas de repetibilidade em relação aos demais métodos. As estimativas dos coeficientes de repetibilidade são de média a alta magnitude, para as variáveis ALT, NP e DC e de baixa magnitude para PMS. Com base no método dos Componentes Principais são necessárias cinco, cinco, duas e onze medidas para altura da planta, número de perfilhos, diâmetro do caule e rendimento de matéria seca, respectivamente, com 80% de confiabilidade.
Subject(s)
PennisetumABSTRACT
Objective: In this study, an in-line near infrared spectroscopy (NIRS) rapid detection model of single-effect concentration process of ArtemisiaeAnnuae Herba(AAH) was established and the impact of absorbance to model was discussed. Methods: Nine batches of concentration process samples were collected inline and partial least square (PLS) method was applied to build its quantitative model which was used to predict an unknown batch of samples. Results: The parameters of PLS model of total acid and soluble solid content were as follows: coefficient of determination (R2) of 0.9623 and 0.9679, root mean square errors of calibration (RMSEC) of 0.7835 and 0.9488, and root mean square errors of cross-validation (RMSECV) of 0.8258 and 0.9780, respectively. Conclusion: Absorbance of concentration process samples of AAH was between 0 and 2.0 and RSEP values of total acid and soluble solid content was less than 10%. It can meet the quality requirements of production process of AAH and indicate that the effect of high absorbance (namely low tansmittance) on NIRS model of AAH can be eliminated by adding samples and using chemometrics when the absorbance is between 0.0 and 2.0.
ABSTRACT
Breeding programs strive to obtain cultivars with superior traits. The association between these characters, such as those estimated by correlation coeficients, are important to the breeding selection process. In this study we analyzed phenotypic and genotypic correlations between yield and other agronomic traits in soybean progenies derived from various crosses to support breeding line selection in the soybean breading program of the Federal University of Uberlandia (UFU). The experiment was carried out in the 2011/2012 growing season at the Capim Branco research station in Uberlandia, Minas Gerais, Brazil. Seventy-one soybean lines were evaluated using a randomized complete block design with three replications. In these plots plants were evaluated for the number of pods, grain yield per plant, number of days for flowering, plant height at flowering, number of days for maturity, plant height at maturity, height of the first pod insertion, number of grains per pod and grain yield per plant. The estimates for genotypic correlations were equal or greater than those for the phenotypic correlations for all the evaluated traits. This suggests a small effect of environmental factors on the trait expression. An exception of this behavior was the correlation between plant height at flowering and plant height at maturity. In this case, although the signs for the genotypic and phenotypic correlations were the same, the value for the last was greater than that for the former. The late flowering and late-maturing plants were taller. Also, selecting plants for higher number of pods ultimately contributed for the selection of plants with higher grain yield. The selection of late-flowering and late-maturing plants have yielded taller plantsin the same way that the selection for a higher pod number could promote the selection and improvement of grains yield trait.
O objetivo dos programas de melhoramento genético de qualquer cultura é a obtenção de cultivares que superem com vantagens as pré-existentes. Desse modo, o conhecimento das relações entre caracteres, tais como estimadas pelas correlações, tem apresentado grande importância para o sucesso dos processos de seleção no melhoramento. Os objetivos deste estudo foram avaliar as correlações fenotípicas e genotípicas entre caracteres agronômicos de linhagens de soja oriundas de diferentes cruzamentos, visando fornecer subsídios para fins de seleção a ser adotado no programa de melhoramento genético de soja da Universidade Federal de Uberlândia. O experimento foi conduzido em uma área experimental localizada na Fazenda Capim Branco, pertencente à Universidade Federal de Uberlândia, no município de Uberlândia, Minas Gerais, na safra 2011/2012. Foram avaliados 71 linhagens de soja em delineamento de blocos completos casualisados com três repetições. Avaliaram-se os caracteres: número total de vagens, produção de grãos por planta, número de dias para o florescimento, altura da planta no florescimento, número de dias para maturidade, altura da planta na maturidade, altura de inserção de primeira vagem, número de grãos por vagem e produção de grãos por planta. Para todos os caracteres, com exceção da correlação entre altura da planta no florescimento e maturidade em que a apesar de apresentarem mesma direção, a magnitude da correlação fenotípica superou a correlação genotípica, as correlações genotípicas foram superiores as fenotípicas e de igual sinal, indicando menor influência do ambiente na expressão dos caracteres. A seleção de plantas mais tardias no florescimento e maturidade, resulta em plantas mais altas nesses estádios de desenvolvimento, bem como a seleção de plantas com maior número de vagens favorece a seleção e melhoramento para o caractere produção de grãos por planta.
Subject(s)
Glycine max , Crop Production , Edible Grain , Plant BreedingABSTRACT
Objective To discuss a convenient and pragmatic method of fitting and optimizing standard curve for determining concentration of serum hepatitis B virus large surface protein(HBV-LP).MethodsEnzyme-linked immunosorbent assay(ELISA)was used to measure the absorbance of standard preparation of HBV-LP.Concentration and absorbance of standard preparation of HBV-LP was carried out curve fitting with 4-parameter formula model and linear model and log-linear model and quadratic polynomial model and cubic polynomial model and S model by program solution of Excel,respectively.The most standard curve for determining concentration of serum HBV-LP was determined with coefficient of determination of regression model.ResultsThe scatterplot of standard preparation of HBV-LP submited nonlinear tendency.There were all significance to regression equation of 4-parameter formula model and linear model and log-linear model and quadratic polynomial model and cubic polynomial model and S model(P
ABSTRACT
To investigate the effect of carbon disulfide on blood pressure, the BP measurements in the periodic health examination results and the medical records of factory clinic were reviewed The study subjects were composed of 1336 male and 544 female workers, who were categorized into three groups by the exposure status-highly exposed, moderately exposed and non-exposed group. The results of the study were as follows; 1. The age-adjusted mean systolic and diastolic BP of male workers were 122.35 mmHg/79.11mmHg in highly exposed, 121.57mmHg/79.05mmHg in moderately exposed and 122.67mmHg/82.27mmHg in non-exposed group. For female workers, BP were 115.13mmHg/74.49mmHg in moderately exposed and 113.48mmHg/74.30mmHg in non-exposed group. 2. In multiple regression analysis of maximum BP against Age and tenure, the slope coefficients of age and tenure on the systolic BP were 0.379, 0.667 respectively and those on the diastolic BP were 0.331, 0.405 respectively in highly exposed male workers. Tenure was a significant variable in this study. For female workers, however, the slope coefficients of tenure on BP were significant only for systolic BP of moderately- expected group. 3. In multiple regression analysis of Bp against age, cumulative exposure index(CEI), cholesterol, all the variables showed significant slope coefficients in male, but age and CEl on systolic BP were significant for female workers (P<0.05). 4. In the multiple analysis of the amount of Bp change and the velocity of Bp change among male workers, the slope coefficients of tenure tended to increase as exposure level increased. Among female workers, the slope coefficients of tenure were significant on the amount of Bp change and the velocity of Bp change in moderately exposed group.