RESUMO
Sorption and desorption determine the amount of an herbicide in soil solution. Therefore, knowledge of the sorption and desorption coefficients in different soils is an essential factor to estimate the potential for environmental contamination by herbicides. We evaluated the feasibility of multivariate and linear discriminant analyses to predict the sorption and desorption capacity of a soil for diuron, one of the most used herbicides on sugarcane plantations. The adsorptive capacity in twenty-seven Brazilian soil samples was estimated using the sorption constant (Kfs) and desorption constant (Kfd) obtained by the Freundlich isotherms. The regression model was created from the sorbed and nonsorbed concentrations of diuron in soils. Ultra-performance liquid chromatography was applied to quantify the diuron concentrations. The multivariate analysis separated the soils into four groups considering the similarity of the following attributes: pH, organic matter, clay, and base saturation. The groups showed a similar pattern of sorption and desorption for diuron: Lom-Lclay: low sorption (5.9 ± 1.2) and high desorption (10.9 ± 0.6); Lclay: low sorption (7.5 ± 1.1) and high desorption (11.4 ± 1.3); Hom-Hclay: high sorption (11.2 ± 1.2) and low desorption (13.8 ± 1.2); HpH-Hclay: high sorption (10.1 ± 1.1) and medium desorption (11.5 ± 1.4). Linear discriminant analysis of these soil attributes was used to classify other soils described in the literature with adsorption capacity. This analysis was able to identify soils with high and low sorption using the pH, organic matter, clay, and base saturation, demonstrating the enormous potential of the technique to group soils with different contamination risks for subterranean waters. Sugarcane crops in northeastern Brazil showed a higher pollution risk through the leaching of diuron. Multivariate analysis revealed significant diuron-related changes in the soil composition of different Brazilian regions; therefore, this statistical analysis can be used to improve understanding of herbicide behavior in soils.
RESUMO
The objective of this work was to evaluate the diversity between accessions of Cucurbita moschata from the Northeast of Brazil and preserved at the Universidade Federal Rural do Semi-Árido (UFERSA) in Mossoró-RN. The experiment was carried out in complete randomized blocks, with two replications and three plants per plot. The treatments consisted of 51 accessions of C. moschata Duch and a commercial cultivar of Cucurbita maximum Duch. After ripening, the fruits were harvested (one fruit per plant) and evaluated for morpho-agronomic descriptors. Univariate and multivariate variance analyzes were performed. From the dissimilarity matrices, accessions were hierarchically grouped by the UPGMA method. The relative contribution of quantitative characters to the divergence was also estimated. There was an effect of accessions (p <0.01 or p <0.05) for all characters in univariate analyzes, indicating that there is heterogeneity between the accessions evaluated. Considering the quantitative descriptors, the accessions formed eight groups and for the qualitative six groups. When considering the two sets of descriptors, the accessions were distributed in eight groups but presenting a greater distribution of accessions. The descriptors that most contributed to the discrimination of accessions were the firmness of the pulp and the length of the fruit.
Assuntos
Variação Genética , CucurbitaRESUMO
ABSTRACT: Melon or muskmelon (Cucumis melo L.) is of considerable economic importance in Brazil. Nearly all the cultivars currently grown are hybrids. Heterosis has been used to advantage in the melon plant, and the use of uniform hybrids is one of the reasons for successful cultivation. The aim of the present study was to evaluate the agronomic potential of yellow melon lines and hybrids. An experiment was conducted in randomized blocks with three replications to evaluate 24 hybrids generated by crosses among three elite lines used as female parents (AF-01, AF-02, and AF-03) and eight lines used as male parents (LAM-01, LAM-02, LAM-03, LAM-04, LAM-05, LAM-06, LAM-07, and LAM-08). Yield and fruit quality traits were evaluated. Partial diallel analysis was carried out to estimate general combining ability and specific combining ability. Additive and non-additive effects were observed for the yield, mean fruit weight, and pulp thickness traits. The lines AF-02, LAM-02, and LAM-03 are the most promising as parents as they more frequently have favorable alleles. The most prominent hybrids in diallel analysis were AF-02 x LAM-02, AF-02 x LAM-03, AF-02 x LAM-04, and AF-03 x LAM-06.
RESUMO: O melão amarelo (Cucumis melo L.) é uma hortaliça de grande importância econômica. Atualmente as cultivares plantadas, em quase sua totalidade, são híbridos. A heterose tem sido explorada no meloeiro, sendo o emprego de híbridos uniformes uma das razões do sucesso da cultura. O objetivo do presente trabalho foi avaliar o potencial agronômico de linhagens e híbridos de melão amarelo. Foi conduzido um ensaio em blocos casualizados com três repetições para avaliar 24 híbridos gerados pelos cruzamentos entre três linhagens elites utilizadas como genitores femininos (AF-01, AF-02 e AF-03), e oito linhagens utilizadas como genitores masculinos (LAM-01; LAM-02; LAM-03; LAM-04; LAM-05; LAM-06; LAM-07 e LAM-08). Foram avaliados caracteres a produção e a qualidade do fruto. Realizou-se a análise dialélica parcial para estimação das capacidades geral e específica de combinação. Observou-se efeitos aditivos e não aditivos para os caracteres produtividade, peso médio do fruto e espessura da polpa. As linhagens AF-02, LAM-02 e LAM03 são as mais promissoras por possuir maior frequência de alelos favoráveis. Os híbridos de maior destaque foram AF-02 x LAM-02, AF-02 x LAM-03, AF-02 x LAM-04 e AF-03 x LAM-06.
RESUMO
O objetivo do presente trabalho foi estudar o efeito da interação genótipos por ambientes sobre a avaliação de famílias de meloeiro. Foram avaliadas 144 famílias na geração S6, em quatro municípios, Mossoró, Baraúna, Assu e Alto do Rodrigues, em um látice simples 12x12. As características avaliadas foram: produtividade, peso médio do fruto, proporção da cavidade interna, espessura da polpa, firmeza da polpa e teor de sólidos solúveis. Constatou-se efeito significativo de famílias nos quatro ambientes de avaliação e na análise conjunta para todas as características. A interação famílias x locais foi acentuada, sendo a estimativa do componente de variância da interação superior àquele da variância genética entre famílias. Ocorreu superioridade na contribuição da parte complexa em relação à simples da interação para todas as características. A interação famílias x ambientes teve reflexo na seleção, pois a resposta correlacionada pela seleção em um ambiente e ganho em outro sempre foi inferior ao ganho da seleção direta. As estimativas de coeficiente de variação genética e variância genética entre famílias foram superestimadas pelo componente da interação famílias x locais, sendo necessárias avaliações em ambientes diferentes. A seleção com base no comportamento médio das famílias foi eficiente, pois proporcionou maiores ganhos de seleção do que aqueles obtidos com base na seleção no ambiente individual.
The objective of this research was to study the genotype x environment effect on the selection of melon families. It was evaluated 144 melon families at four sites of Rio Grande do Norte State, Brazil. The experiments were carried out in a design of simple lattice 12x12 in Mossoró, Baraúna, Assu and Alto do Rodrigues sites. The traits assessing were yield, average of weight fruit, intern cavity proportion, pulp thickness, pulp firmness and content solids soluble. It was observed effect of families in all sites and the join analysis for all traits. The family x site interaction was high and the estimation of the interaction variance component was higher than the genetic variance among families. The complex interaction was higher than the simple one. The family x site interaction reflected in the selection, as the correlated response to selection in one environment observed in another was always lower than the gain of direct selection. The estimates of the genetic variation coefficient and genetic variance were overestimated by family x site interaction, consequently, the evaluation should be carried out in different sites. The selection based on the mean over sites was effectiveness because the genetic expected that gains were more expressive than gains based in the individual environment.
RESUMO
Objetivou-se, com o trabalho, avaliar alguns atributos de qualidade de diferentes genótipos de cebola (Allium cepa L.), cultivados em Mossoró-RN. O experimento foi realizado na horta experimental no Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido, em delineamento de blocos casualizados completos e quatro repetições. Os tratamentos foram constituídos pelos genótipos de cebola CNPH 6415, CNPH 6047, CNPH 6244, CNPH 6400 Chata, CNPH 6400 Redonda, CPACT 1, CPACT 2, CPACT 3, Granex 429, Belém IPA 9, BRS Cascata, Crioula Alto Vale, Bola Precoce, Primavera, Régia, Valeouro IPA-11, Brisa e Alfa São Francisco. As características avaliadas foram teor de sólidos solúveis totais, acidez total titulável, teor de vitamina C e teor de ácido pirúvico (pungência). Foram observadas diferenças significativas entre os genótipos para todas as características avaliadas. Os genótipos apresentaram uma variação significativa para todas as características avaliadas, confirmando dessa forma que o fator genético é determinante na caracterização de cada material. O teor de sólidos solúveis totais variou de 6,67 a 11,63 (º Brix), vitamina C de 22,7 a 46,81 (mg ácido ascórbico/100 ml de suco) e a acidez total titulável de 0,19 a 0,45 ( por cento de ácido pirúvico). Os genótipos apresentaram pungência intermediária com variação de 5,0 a 12,73 (µmol/g), sendo os menos pungentes Granex 429, CNPH 6047, Régia, Primavera e Belém IPA 9.
The aim of this work was to evaluate some attributes of quality of different genotypes of onion (Allium cepa L.), cultivated in Mossoró-RN. The experiment was carried out in the vegetable garden of Plant Science Department at Universidade Federal Rural do Semi-Árido. The experimental outline was of randomized complete blocks with four replications. The treatments were constituted by the genotypes of onion CNPH 6415, CNPH 6047, CNPH 6244, CNPH 6400 Chata, CNPH 6400 Redonda, CPACT 1, CPACT 2, CPACT 3, Granex 429, Belém IPA 9, BRS Cascata, Crioula Alto Vale, Bola Precoce, Primavera, Régia, Valeouro IPA-11, Brisa and Alfa São Francisco. The evaluated characteristics were total soluble solid, titrate acidity, vitamin C and pyruvic acid (pungency). The genotypes presented a significant variation for all the evaluated characteristics, confirming in such a way that the genetic factor is determinative in the characterization of each material. The total soluble solid varied from 6,67 to 11,63 (ºBrix), vitamin C from 22,7 to 46.81 (mg acid ascórbico/100 ml of juice) and the titrate acidity from 0,19 to 0.45 ( percent of pyruvic acid). The genotypes presented intermediate pungency with variation of 5,0 the 12,73 (µmol/g), being the least pungent Granex 429, CNPH 6047, Régia, Primavera e Belém IPA 9. Considering the group of the appraised characteristics, the genotypes BR Cascata, CNPH 6244, Belém IPA 9, IPA 11 and Primavera were the best in the conditions of Mossoró.