Leandro Simões Azeredo Gonçalves

Análise biométrica de ganhos por seleção em população de milho pipoca de quinto ciclo de seleção recorrente

Aiming to select superior progenies for concentration of favorable alleles in a popcorn population on the fifth cycle of intrapopulation full-sib recurrent selection, two hundred progenies were evaluated for six agronomic traits, including grain yield and popping expansion, in randomized complete block design with two replications within sets, in two distinct environments: Colegio Estadual Agricola Antonio Sarlo, in Campos dos Goytacazes, and Experimental Station of PESAGRO-RIO, located in Itaocara, Rio de Janeiro State, in 2007/2008. There were significant differences among families within sets in all traits, indicating the presence of genetic variability to be exploited in the future cycles. The utilized selection indexes were the Mulamba and Mock; and Smith and Hazel. The Mulamba and Mock index propitiated more elevated magnitudes of the predicted gains for most of the traits, including popping expansion and grain yield, with values of 6.01 and 8.53%, respectively, utilizing arbitrary weight attributed by tentative.

Association between advanced generations and genealogy in inbred lines of snap bean by the Ward-Modified Location Model

The Ward-MLM strategy first proposed by Franco et al. (Crop Sci 38:1688–1696, 1998) is a useful method for analyzing genetic divergence for genealogical comparisons. However, this method has not yet been applied in conjunction with early generation testing (EGT) and single seed descent (SSD) procedures in autogamous plant species bred to advanced generations. In this study, we quantified the diversity of 120 recombinant snap bean lines from the F6:7 generation, advanced by SSD from the application of EGT in F2, to investigate the association between the grouping of lines and genealogy using the Ward-MLM method. Four F2 populations with high pod yields were selected from crosses among five genotypes. The segregating population was advanced to F6:7 by the SSD method. The traits of plant height, mean pod length, number of seeds per pod, mean number of days to flowering, mean pod fiber content and pod yield were evaluated. Based on the distribution of lines in the groups by the Ward-MLM approach, variability was verified in the four populations. Furthermore, the early selection in F2 did not limit the variability in the expression of genotypes with better agronomic performance. Thirty lines advanced by SSD for each population studied were sufficient to obtain superior genotypes. There was a relationship between the genealogy and groupings in F6:7, as evidenced by Group 1, G1, which contained the greatest number of lines from the crossing that were significantly enriched for their mean pod yield and Group 3, G3, which comprised the highest number of lines with a shorter plant type. These two traits, respectively, are the first and second most important traits for group stratification.

Magnitude of the genetic base of commercial popcorn and in recommendation in Brazil

Objetivou-se neste trabalho quantificar a diversidade genetica entre genotipos de milho-pipoca comerciais e em fase de recomendacao no Brasil em tres ambientes, utilizando 11 caracteristicas agronomicas e marcador molecular do tipo ISSR. O ambiente de Campos dos Goytacazes revelou a formacao de grupos que foram mais consonantes quando comparados com os outros ambientes. Nos dados moleculares verificou-se a presenca de cultivares recomendadas em mesmo grupo, como ocorreu com UFVM2 Barao de Vicosa, IAC 125, Zelia e Jade. Esse resultado e um motivo de alerta para os poucos melhoristas de milho pipoca do Brasil, no sentido de promocao de maior diversidade genetica entre programas de melhoramento realizados por instituicoes publicas e privadas no pais. Verificou-se uma correlacao praticamente nula entre a matriz de distância obtida pelo marcador ISSR com as matrizes obtidas pelos dados agronomicos.

Descritores quantitativos na estimativa da divergência genética entre genótipos de mamoneira utilizando análises multivariadas

Knowledge of the diversity is of fundamental importance for plant breeding, as well as for the identification of combinations that can express high heterosis levels, increase the expectation of selection of superior segregating genotypes, based on the accumulation of varibility by crosses between dissimilar genotypes. Several multivariate methods can be used to investigate diversity. The choice is made according to the accuracy desired by the researcher, the ease of the analysis and how the data were obtained. The purpose of this study was to evaluate the diversity of 11 castor bean genotypes in the north and northwest of Rio de Janeiro, Brazil and to investigate the potential of each genotype for future breeding programs. Six quantitative traits (plant height, total raceme length, length of the region with fruiting raceme, length of the region without fruiting raceme, number of fruits per raceme and total yield) were evaluated in a randomized complete block design with four replications. The differences between treatments were significant for all traits evaluated. Results of multivariate analyses (UPGMA, Tocher and canonical variables) showed similar results forming three groups each. The genotypes Nordestina, IAC 80, Al Guarany, Paraguacu, Mirante and IAC 226 proved promising for the studied regions. For crossing or breeding programs, the combinations Al Guarany x Nordestina, Al Guarany x IAC 80 and Nordestina x IAC 80 are recommended.

Herança de caracteres relacionados à produção de frutos em Capsicum baccatum var. pendulum com base em análise dialélica de Hayman

Este trabalho teve por objetivo estimar parâmetros geneticos relacionados a producao de frutos em um dialelo de pimenta (Capsicum baccatum var. pendulum). Foram avaliados cinco genitores de pimenta (UENF 1616, UENF 1624, UENF 1629, UENF 1639 e UENF 1732) e seus respectivos hibridos F1, a partir de um dialelo completo, sem reciprocos. O experimento foi conduzido em cultivo protegido (politunel), na area de convenio UENF/PESAGRO-RIO, Campos dos Goytacazes, no periodo de julho a dezembro de 2009. O delineamento experimental foi em blocos casualizados, com tres repeticoes e nove plantas por parcela. Avaliaram-se as seguintes caracteristicas agronomicas: diâmetro da copa (DC), altura de planta (ALTP), dias para a frutificacao (DF), numero de frutos por planta (NFP), peso medio do fruto (PMF), massa seca do fruto (MSF); teor de massa seca (TMS), comprimento do fruto (CF), diâmetro do fruto (DIAM), espessura da polpa (ESP), teor de solidos soluveis totais (TSS) e producao por planta (PROD). Somente as caracteristicas PMF, MSF e PROD tiveram ausencia de significância nos tres testes de suficiencia do modelo aditivo-dominante, indicando haver homogeneidade entre as variâncias e covariâncias e, consequentemente, ausencia de epistasia no controle destas caracteristicas. Para PMF e MSF, os efeitos genicos aditivos foram os mais importantes. Por sua vez, na expressao de PROD o efeito de dominância foi o mais importante. Verificou-se dominância parcial para PMF e MSF e sobredominância para PROD. Os genitores UENF 1616 e UENF 1629 foram os que tiveram as maiores concentracoes de alelos favoraveis para as tres caracteristicas em estudo.Resumo - Este trabalho teve por objetivo estimar parâmetros geneticos relacionados a producao de frutos em um dialelo de pimenta (Capsicum baccatum var. pendulum). Foram avaliados cinco genitores de pimenta (UENF 1616, UENF 1624, UENF 1629, UENF 1639 e UENF 1732) e seus respectivos hibridos F 1 , a partir de um dialelo completo, sem reciprocos. O experimento foi conduzido em cultivo protegido (politunel), na area de convenio UENF/PESAGRO-RIO, Campos dos Goytacazes, no periodo de julho a dezembro de 2009. O delineamento experimental foi em blocos casualizados, com tres repeticoes e nove plantas por parcela. Avaliaram-se as seguintes caracteristicas agronomicas: diâmetro da copa (DC), altura de planta (ALTP), dias para a frutificacao (DF), numero de frutos por planta (NFP), peso medio do fruto (PMF), massa seca do fruto (MSF); teor de massa seca (TMS), comprimento do fruto (CF), diâmetro do fruto (DIAM), espessura da polpa (ESP), teor de solidos soluveis totais (TSS) e producao por planta (PROD). Somente as caracteristicas PMF, MSF e PROD tiveram ausencia de significância nos tres testes de suficiencia do modelo aditivo-dominante, indicando haver homogeneidade entre as variâncias e covariâncias e, consequentemente, ausencia de epistasia no controle destas caracteristicas. Para PMF e MSF, os efeitos genicos aditivos foram os mais importantes. Por sua vez, na expressao de PROD o efeito de dominância foi o mais importante. Verificou-se dominância parcial para PMF e MSF e sobredominância para PROD. Os genitores UENF 1616 e UENF 1629 foram os que tiveram as maiores concentracoes de alelos favoraveis para as tres caracteristicas em estudo. Palavras-chave - Pimenta. Melhoramento de plantas. Hibridacao vegetal. Controle genetico.

Selecting pre-cultivars of popcorn maize based on nonparametric indices

C3, UNB2U-C4 e UNB2U-C5) e oito hibridos (Zelia, Jade, IAC 112, P 1 x P 3 , P 1 x P 7 , P 2 x P 4 , P 2 x P 9 e P 3 x P 7 ), em cinco ambientes. O delineamento experimental adotado foi blocos ao acaso, com tres repeticoes, tendo sido avaliadas as caracteristic as altura de planta, estande, tombamento, capacidade de expansao e rendimento de graos. Os efeitos dos genotipos e ambientes foram significativos para todas as caracteristic as, enquanto que suas interacoes o foram apenas para tombamento e rendimento de graos. Os indices de Garcia e da soma de classificacao foram positivamente correlacionados na classificacao dos genotipos, ambos permitindo indicar as pre-cultivares UNB2U-C5 e P 1 x P 7 como as de melhor desempenho para regioes Norte e Noroeste do Estado do Rio de Janeiro. Palavras-chave: Zea mays L. Valor de cultivo e uso. Caracteristicas agronomicas. Capacidade de expansao.

Quantificação da divergência genética entre acessos de goibeira por meio da estratégia Ward-MLM

The present study aimed at evaluating the genetic divergence among 138 guava accessions coming from the Germplasm Collection of the Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF) based on morphological, agronomic and physic-chemical traits by Ward - Modified Location Model (MLM). Thirteen descriptors were evaluated, five qualitative (flesh color, fruit surface, shape at stalk end , neck width and uniformity of the flesh color) and eight quantitative (fruit weight, fruit diameter, fruit length, pulp revenue, soluble solids contents, total titratable acidity, total soluble solids/total titratable acidity ratio and ascorbic acid). High genetic variability was detected considering morphological, agronomic and physic-chemical traits in the 138 guava accessions studied. The procedure of the likelihood function showed that the ideal numbers of groups was eight, with an increment value of 67.51. Group III was considered the most distant, while groups I, II, IV, V and VI the closest. The Ward- MLM procedure is a useful tool for detecting genetic divergence and cluster accessions using both qualitative and quantitative variables.

Biometria aplicada ao melhoramento intrapopulacional do maracujazeiro amarelo

The objective of the study was to estimate genetic parameters associated with eleven agronomic traits of a population of yellow passion fruit under recurrent selection, using 140 full-sibling progenies from the second cycle, planted in October 2007 in a simple square lattice design and in plots consisting of three plants. The mean squares of their features revealed F-test significance for the effect of progeny, indicating that there is genetic variability to be explored in the next cycles. Estimates of heritability coefficients ranged from 19.54 to 71.38%. The averages of the main characteristics of agronomic importance in the studied population were higher than those of the controls, confirming the potential of the population to generate a superior population with the accumulation of favorable alleles in successive processes of selection. Estimates of genetic and phenotypic parameters of the main characteristics of economic importance reveal the possibility of success in the selection of superior progenies of yellow passion fruit, with the aim of registration and protection of a new cultivar.

Gene effect and heterosis in Capsicum baccatum var. pendulum

Heterosis has been exploited in Capsicum annuum commercial hybrids; however, the use of heterosis in C. baccatum still remains to be explored, and studies related to the genetics and breeding of this species are scarce. The present study aimed to estimate the combining ability of five parents of C. baccatum var. pendulum , representatives of two distinct types of fruits (namely, ladys finger and cambuci), to calculate heterosis and to evaluate the agronomic potential of the hybrids for yield and fruit quality. The hybrids were produced from a complete diallel without reciprocals. The parents and hybrids were evaluated under field conditions in a randomized block design with three replications, and the following traits were assessed: number of fruits per plant, fruit weight, yield per plant, fruit length, fruit diameter and soluble solids. All traits were significant for general and specific combining ability, indicating that additive and non-additive effects are involved in the genetic control of these traits. The hybrid combinations between the types ladys finger and cambuci provided elongated fruits with smaller diameters and greater weight compared with the parents of the cambuci type. However, these factors did not lead to a significant increase in the yield per plant due to the decreased number of fruits except in hybrid UENF 1616 x UENF 1732. Considering only the parents and hybrids within each type of fruit, the genitor UENF 1624 (ladys finger) and the hybrid UENF 1639 x UENF 1732 (cambuci x cambuci) stood out for achieving a high yield per plant.

UENF 14: a new popcorn cultivar

The aim of this work is to present the features of the popcorn cultivar UENF 14, developed from five cycles of recurrent selection of the population UNB-2U, to the scientific community. The cultivar produces yields of 3047.58 kg ha-1 and has popping expansion of 35.69 mL g-1.