ABSTRACT The aim of the present study was to investigate relations among ten traits in super-sweet corn genotypes assessed by means of simple correlation, path and canonical variable analyses, as well as to investigate the relative importance of such traits to the super-sweet corn breeding program developed at Darcy Ribeiro Northern Fluminense State University in order to develop strategies able to improve the efficiency in the selection of superior genotypes. Thus, trials comprising 3 × 6 partial diallel of super-sweet (sh2) corn were carried out, according to a short_textrandomized block design (RBD)short_text with four repetitions, in two different environments located in Northern Rio de Janeiro State, Brazil (Itaocara and Campos dos Goytacazes counties). The correlation study showed that traits such as ear diameter and useful short_textearshort_text length contributed the most to increase short_textearshort_text yield (without husk); the variable ear diameter stood out for having stronger direct effect on ear yield, as well as for presenting high heritability (0.95). The trait number of grains per ear row contributed the most to the variation between hybrids, whereas the trait useful ear length contributed the least. The canonical variables showed that the genetic backgrounds of sh2-gene donor populations had effect on recurrent populations, even after five backcrossing cycles, thus resulting in the formation of two divergent groups.

Abstract To date, no studies on the inheritance of Fusarium spp. ear rot resistance in popcorn are available. The purpose of this paper was to investigate the additive-dominance model to estimate the genetic components of variance, heritability and the inheritance pattern in a diallel for popcorn, by Hayman’s approach. The experiment was carried out in two environments, using eight parent lines. The following traits were measured: grain yield (GY), popping expansion (PE), incidence of ears infected by Fusarium (FusIE), total number of kernels infected by fungi (FunIK) and total number of kernels infected by Fusarium spp. (FusIK). The results indicated that the incidence of FusIK (Fusarium-infected kernels), FunIK (fungus-infected kernels), and FusIE (Fusarium-infected ears) is controlled by dominant genes. Parent L77 had a high number of favorable alleles for all resistance-related traits, as well as for PE. The strategy recommended for reduction of FunIK, FusIK, and FusIE consists of exploiting hetorosis using inbred lines with favorable alleles.

É importante dimensionar adequadamente o tamanho de amostra, para estimação, com confiabilidade aceitável, do coeficiente de correlação linear de Pearson entre pares de caracteres. O objetivo deste experimento foi determinar o tamanho de amostra (número de plantas) para estimação do coeficiente de correlação linear de Pearson, entre 21 caracteres de crambe (Crambe abyssinica Hochst). Um experimento em campo foi conduzido no ano de 2008. Na colheita foram selecionadas, aleatoriamente, 75 plantas, nas quais foram mensurados 21 caracteres. Foram calculadas medidas de tendência central, de variabilidade, de assimetria e de curtose, verificada a normalidade e investigada a linearidade entre os caracteres. Foi calculado o tamanho de amostra, para estimação do coeficiente de correlação de Pearson, para as amplitudes do intervalo de confiança de 95%, iguais a: 0,15; 0,20; 0,25; 0,30; 0,35 e 0,40, para cada um dos 210 pares de caracteres. Para os 210 pares de caracteres de crambe estudados, o tamanho de amostra, para estimação do coeficiente de correlação linear de Pearson, para a amplitude do intervalo de confiança de 95% igual a 0,15, oscilou entre 8 e 665 plantas.

It is important to dimension correctly the sample size, to estimate the Pearson correlation coefficient among pairs of characters, with acceptable reliability. The aim of this research was to determine the sample size (number of plants) to estimate the Pearson correlation coefficient among 21 characters of crambe (Crambe abyssinica Hochst). An experiment was conducted in the year 2008. At harvest, 75 plants were selected randomly and measured 21 characters. The measures of central tendency, variability, skewness and kurtosis, were done. Normality was verified and investigated the linearity among the characters. The sample size to estimate the Pearson correlation coefficient was calculated, for the amplitude of the confidence interval of 95%, equal to: 0.15; 0.20; 0.25; 0.30; 0.35 and 0.40, for each of 210 pairs of characters. For the 210 characters pairs of crambe, the sample size to estimate the Pearson correlation coefficient, to the amplitude of the confidence interval of 95% equal to 0.15, ranged from 8 to 665 plants.