Interference of genotype-by-environment interaction in the selection of inbred lines of yellow melon in an agricultural center in Mossoró-Assu, Brazil

ABSTRACT. The aims of this study were to i) identify the influence of the GxE interaction in the selection of inbred lines of melon, and ii) test the efficiency of different indexes in the selection of inbred lines with a higher yield potential and better quality fruit. For these purposes, 98 inbred lines of yellow melon and two commercial controls, Vereda and AF-646, were evaluated in a randomized block design with two replications, at the conditions present in Mossoró and Baraúna. Analyses of the following traits were performed: fruit yield, mean fruit weight, pulp thickness, pulp firmness and soluble solids content. A complex portion of the GxE interaction was predominantly detected for all traits. The recommendation in this case is to promote selection in each environment. Alternatively, selection based on the average behavior of the inbred lines is the strategy that generates the greatest gains, approaching those obtained through direct selection in each specific environment. The selection indexes aimed at reducing the expression of all traits proved to be best for both locations. The index constructed for Baraúna allowed the selection of a greater number of inbred lines with a higher yield potential and better quality fruit and, thus, greater efficiency. Keywords: Cucumis melo L, segregant populations, genetic gains, inbred lines extraction, hybrids, selection indexes. Interferência da interação genótipo por ambiente na seleção de linhagens de melão amarelo no agropolo Mossoró-Assu, Brasil RESUMO. Objetivou-se com esse estudo: i) identificar a interferência da interação GxE no processo de seleção de linhagens de melão e; ii) testar a eficiência de índices na seleção de linhagens com maior potencial produtivo e melhor qualidade de fruto. Para isto, avaliaram-se 98 linhagens de melão amarelo e duas testemunhas, Vereda e AF-646, em blocos casualizados com duas repetições, em Mossoró e Baraúna, localizadas no Agropolo produtor desta hortaliça. Avaliaram-se os caracteres produtividade de frutos, massa média de frutos, espessura de polpa, firmeza de polpa e sólidos solúveis. Detectou-se uma predominância da porção complexa na interação GxE em todos os caracteres. A recomendação, neste caso, é promover a seleção em cada ambiente. Alternativamente, a seleção baseada no comportamento médio das linhagens é a estratégia que gera ganhos mais próximos àqueles obtidos pela seleção direta em cada ambiente específico. Os índices de seleção, com o propósito de reduzir a expressão de todos os caracteres, se mostraram melhores para ambas as localidades. Àquele construído para Baraúna permitiu selecionar um maior número de linhagens com elevado potencial produtivo e com melhores qualidades de fruto, sendo assim, mais eficiente. Palavras-chave: Cucumis melo L, populações segregantes, ganho genético, extração de linhagens, híbridos, índices de seleção

Herança do teor de betacaroteno em melão

The objective of this work was to determine the inheritance of beta‑carotene content in melon (Cucumis melo). The AC-16 accession (Cucumis melo subsp. melo var. acidulus) – with a low beta-carotene content and white mesocarp – was crossed with the Vedrantais cultivar (C. melo subsp. melo var. cantalupensis) – with a high beta-carotene content and salmon colored mesocarp –, to obtain the F1, F2, BC1 and BC2 generations. The AC‑16 and 'Vedrantais' parents, the F1 and F2 generations, and the BC1 and BC2 backcrosses of each parent were evaluated. The quantification of beta‑carotene was carried out in a high-performance liquid chromatography system. Mean components related to the additive and dominance effects, additive and dominance variances, and heritability were estimated. The beta‑carotene content was high in 'Vedrantais' (17.78 µg g-1) and low in AC-16 (0.34 µg g-1). The following results were observed: additive and dominance effects on the genetic control of the character, incomplete character dominance, estimated number of loci close to two, greater variance for segregating populations (F2 and backcrosses), and heritability values in the broad (87.75%) and narrow (64.19%) senses. The beta-carotene content in melon is controlled by a major effect gene, with additive and dominance effects associated with polygenes with additive effects.O objetivo deste trabalho foi determinar a herança do teor de betacaroteno em melão (Cucumis melo). O acesso AC-16 (Cucumis melo subsp. melo var. acidulus) – com baixo teor de betacaroteno e mesocarpo branco – foi cruzado com a cultivar Vedrantais (C. melo subsp. melo var. cantalupensis) – com alto teor de betacaroteno e mesocarpo de cor salmão –, para obtenção das gerações F1, F2, RC1 e RC2. Avaliaram-se os genitores AC‑16 e 'Vedrantais', as gerações F1 e F2, e os retrocruzamentos de cada genitor RC1 e  RC2. A quantificação do betacaroteno foi realizada em sistema de cromatografia líquida de alto desempenho. Foram estimados os componentes de média relacionados aos efeitos aditivos e de dominância, as variâncias aditiva e de dominância e a herdabilidade. O teor de betacaroteno foi alto (17,78 µg g-1) em 'Vedrantais' e baixo em AC-16 (0,34 µg g-1). Observaram-se os seguintes resultados: efeito aditivo e de dominância no controle genético do caráter, dominância de caráter incompleta, número estimado de loci próximo de dois, maior variância para populações segregantes (F2 e retrocruzamentos), e valores de herdabilidade nos sentidos amplo (87,75%) e restrito (64,19%). O teor de betacaroteno em melão é controlado por um gene de efeito maior, com efeitos aditivos e de dominância associados a poligenes com efeitos aditivos

Cantaloupe melon (Cucumis melo L.) conservation using hydrocooling Rev

ABSTRACT RESUMO Cantaloupe melon (Cucumis melo L.) conservation using hydrocooling Maintaining cantaloupe melon at field temperature impairs conservation as it speeds up cell metabolism and transpiration, and, consequently, reduces shelf life. This study aimed to evaluate the conservation of Torreon hybrid cantaloupe using the hydrocooling treatment. Fruits were harvested at the commercial maturity stage (60 days after planting), in the morning, at the Nova California Farm, municipality of Mossoró-RN, in September 2007. One set of fruit was immersed in chilled water at 5 ºC for 5 min, at the packing house, while the remaining set was not hydro cooled. Then, both sets (treated and untreated with hydrocooling) were pre-cooled in air forced tunnels at 7 ºC, until the temperature in the pulp reached 10 ºC. Both fruit sets were stored for 0, 14, 21, 28 and 35 days under modified atmosphere at 3 ± 1 o C and 90 ± 5% RH. After each storage period, the fruits were incubated in an atmosphere-controlled chamber at 20 ± 2 o C and 80 ± 5% de RH, for seven days. The following characteristics were evaluated: external and internal appearance, mass loss, soluble solids, firmness and titrable acidity. The experiment was arranged in a completely randomized split-plot design with four replications of three fruits. The plots consisted of the hydrocooling conditions (with and without fruit soaking in chilled water), and the sub-plots consisted of the storage times (0, 14, 21, 28 and 35 days).The treatment with hydrocooling was efficient in keeping the firmness and soluble solids of the fruits and shortened the pre-cooling time in the cooling tunnel. However, hydrocooling did not increase fruit shelf-life. Conservação de melão Cantaloupe (Cucumis melo L.) com o uso de hidrorresfriamento A manutenção da temperatura de campo dos frutos é prejudicial à sua conservação, porque acelera o metabolismo celular e a transpiração e, como consequência, reduz sua vida útil. Este trabalho teve por objetivo avaliar a conservação do melão Cantaloupe, híbrido 'Torreon', com o uso de hidrorresfriamento. Os frutos foram colhidos em setembro de 2007, pela manhã, na Fazenda Nova Califórnia, localizada no município de Mossoró-RN, na maturidade comercial (60 dias após a semeadura). Na casa de embalagem da fazenda, um grupo de frutos foi pré-resfriado (imersão em água fria, a 5 ºC, por 5 min.), enquanto o outro grupo permaneceu sem resfriar. Logo após, os dois grupos foram submetidos a um pré-resfriamento em túneis de circulação forçada de ar, à temperatura de 7 ºC, até que a polpa atingisse 10 ºC. Ambos foram armazenados por 0, 14, 21, 28 e 35 dias, sob atmosfera modificada, a 3 ± 1 o C e 90 ± 5% de UR. Após cada intervalo de tempo, os frutos foram transferidos para uma câmara regulada a 20 ± 2 o C e 80 ± 5% de UR, em que permaneceram po

Indirect selection for content of carotenoid in pumpkin accessions

Carotenoid quantification in foods can be performed by various techniques, such as spectrophotometry, mass spectrometry, high performance liquid chromatography, gas chromatography and colorimetry. The objective of this study was to verify the feasibility of indirect selection of total carotenoids in pumpkin accessions. The experimental design was in complete randomized blocks with two replications and three plants per plot. The treatments consisted of 51 Cucubita moschata Duch accessions from the DCAF/UFERSA Cucurbitaceae germplasm collection and a commercial C. maxima Duch cultivar. After maturation, the fruits were harvested and colorimetric and total carotenoid contents were evaluated. Pulp color intensity parameters and hº angle indicated the possibility of indirect selection of accessions with higher total carotenoid contents. The ABO22 access presented higher total carotenoid content under the evaluation conditions of the experiment. Highlights There is variability in the total carotenoid content in pumpkin accessions. The pumpkin accessions studied have potential for food biofortification. Feasibility of indirect selection in pumpkin accessions for high total carotenoid content.Carotenoid quantification in foods can be performed by various techniques, such as spectrophotometry, mass spectrometry, high performance liquid chromatography, gas chromatography and colorimetry. The objective of this study was to verify the feasibility of indirect selection of total carotenoids in pumpkin accessions. The experimental design was in complete randomized blocks with two replications and three plants per plot. The treatments consisted of 51 Cucubita moschata Duch accessions from the DCAF/UFERSA Cucurbitaceae germplasm collection and a commercial C. maxima Duch cultivar. After maturation, the fruits were harvested and colorimetric and total carotenoid contents were evaluated. Pulp color intensity parameters and hº angle indicated the possibility of indirect selection of accessions with higher total carotenoid contents. The ABO22 access presented higher total carotenoid content under the evaluation conditions of the experiment. Highlights There is variability in the total carotenoid content in pumpkin accessions. The pumpkin accessions studied have potential for food biofortification. Feasibility of indirect selection in pumpkin accessions for high total carotenoid content

Genotype x environment interaction of melon families based on fruit quality traits

Significant genotype vs. environment interaction (G x E) is expected as a result of geographical diversity and differences in management techniques in melon growing. Ninety-six F3 families from the cross between inodorus and conomon melons were evaluated in three environments for studying interaction. The G x E interaction, genetic parameters, and direct and indirect gains were estimated. Average weight of the fruit, pulp thickness, cavity thickness, pulp firmness, and soluble solids were evaluated. The simple part of the G x E interaction was always greater than 99%, except for pulp firmness, where there was predominance of the complex part. The coefficient of genetic variation and genetic variance were overestimated by the G x E interaction. The direct gains from selection were higher than the indirect, except when selection was made by the mean of the three environments. Genotype assessments in more than one location are necessary, but selection should be made by the mean values of families in the environments

QUALIDADE DO MAMÃO 'FORMOSA' SUBMETIDO A DIFERENTES TEMPERATURAS DE REFRIGERAÇÃO

The objective of this work was evaluating the principal alterations of the chemical properties of quality of the papaya 'Formosa' under refrigerated storage. The harvest of fruits was accomplished in a commercial planting located in the municipal district of Baraúna-RN. The storage happened in cameras under controlled conditions of temperatures (8, 10 and 12 ºC ± 1 ºC) and relative humidity of the air (90 ±5%) during periods of 7, 14, 21 and 28 days. After each period, the papayas were transferred to environmental conditions (20 ± 1oC 60 ± 5% UR) where a period of shelf life of seven days was simulated. Then, the papayas were analyzed regarding the titratable acidity (ATT), C vitamin, total soluble solids (SS), starch, reducing and non-reducing sugars. A completely randomized experimental design was used, in a factorial 3 x 4 outline (temperatures x time of storage), with five replications and two fruits per plot. The best extension for the post harvest useful life of papaya 'Formosa' was esteemed for the fruits submitted to 10 °C and 90 ± 5% UR up to 20 days, with soluble solids above 12% and C vitamin around 40 mg×100 g-1. The fruits submitted to 8 °C, 90 ± 5% UR had the worst estimates, presenting the smallest contents of SS

COMPORTAMENTO DE CULTIVARES DE MILHO NOS TABULEIROS COSTEIROS DO ESTADO DE ALAGOASCOMPORTAMENTO DE CULTIVARES DE MILHO NOS TABULEIROS COSTEIROS DO ESTADO DE ALAGOAS

O presente estudo objetivou subsidiar os agricultores Alagoanos na escolha de cultivares de milho portadores de atributos agronômicos desejáveis. Os tratamentos consistiram no cultivo de quarenta cultivares de milho (quatro variedades de polinização aberta, oito híbridos triplos, oito híbridos duplos e vinte híbridos simples). Utilizou-se o delineamento em blocos casualizados com três repetições. As variáveis analisadas foram: Dias para atingir o florescimento masculino, altura das plantas, altura de inserção da espiga, matéria seca, stand final de plantas, produtividade de grãos, correlação fenotípica e divergência genética. Maiores produtividades de grãos estão correlacionadas positivamente com a população final de plantas por hectare; quanto maior a altura de plantas, maior a altura de inserção da primeira espiga, menor a produtividade de grãos. O híbrido simples AG-7000 apresenta características desejáveis para o aumento da produção de grãos nos Tabuleiros Costeiros do Estado de Alagoas

Interference of genotype-by-environment interaction in the selection of inbred lines of yellow melon in an agricultural center in Mossoró-Assu, Brazil

ABSTRACT. The aims of this study were to i) identify the influence of the GxE interaction in the selection of inbred lines of melon, and ii) test the efficiency of different indexes in the selection of inbred lines with a higher yield potential and better quality fruit. For these purposes, 98 inbred lines of yellow melon and two commercial controls, Vereda and AF-646, were evaluated in a randomized block design with two replications, at the conditions present in Mossoró and Baraúna. Analyses of the following traits were performed: fruit yield, mean fruit weight, pulp thickness, pulp firmness and soluble solids content. A complex portion of the GxE interaction was predominantly detected for all traits. The recommendation in this case is to promote selection in each environment. Alternatively, selection based on the average behavior of the inbred lines is the strategy that generates the greatest gains, approaching those obtained through direct selection in each specific environment. The selection indexes aimed at reducing the expression of all traits proved to be best for both locations. The index constructed for Baraúna allowed the selection of a greater number of inbred lines with a higher yield potential and better quality fruit and, thus, greater efficiency

Comportamento de cultivares de milho nos tabuleiros costeiros do estado de Alagoas

The present study aimed to subsidize farmers Alagoanos the choice of maize cultivars carrying desirable agronomic attributes. The treatments consisted of the cultivation of forty varieties of maize, which were: Four open pollinated varieties, eight hybrids triples, eight hybrids doubles and twenty hybrid single cross. The design was a randomized block design with three replications. The variables analyzed were: days to reach the male flowering, plant height, height of ear insertion, dry matter, final plant stand, grain yield, phenotypic correlation and genetic divergence. Highest corn grain yield was positively correlated with the final stand of plants per hectare, the higher the plant height, the greater the height of first ear, the lower the yield. Simple hybrid AG-7000 has characteristics desirable for the increase of grain production in the Coastal Plains of the State of Alagoas.O presente estudo objetivou subsidiar os agricultores Alagoanos na escolha de cultivares de milho portadores de atributos agronômicos desejáveis. Os tratamentos consistiram no cultivo de quarenta cultivares de milho (quatro variedades de polinização aberta, oito híbridos triplos, oito híbridos duplos e vinte híbridos simples). Utilizou-se o delineamento em blocos casualizados com três repetições. As variáveis analisadas foram: Dias para atingir o florescimento masculino, altura das plantas, altura de inserção da espiga, matéria seca, stand final de plantas, produtividade de grãos, correlação fenotípica e divergência genética. Maiores produtividades de grãos estão correlacionadas positivamente com a população final de plantas por hectare; quanto maior a altura de plantas, maior a altura de inserção da primeira espiga, menor a produtividade de grãos. O híbrido simples AG-7000 apresenta características desejáveis para o aumento da produção de grãos nos Tabuleiros Costeiros do Estado de Alagoas.Este estudio tuvo como objetivo subvencionar a los agricultores Alagoanos la elección de cultivares de maíz en con características agronómicas deseables. Los tratamientos consistieron en el cultivo de cuarenta variedades de maíz (cuatro variedades de polinización abierta, ocho híbridos triples, ocho híbridos dobles y veinte híbridos simples). Se utilizó un diseño de bloques al azar con tres repeticiones. Las variables fueron: días para llegar a la altura de la floración, altura de la planta, altura de los oídos en primer lugar, la materia seca, la población final de la planta, rendimiento de grano, la correlación y la divergencia fenotípica. El mejor rendimiento de grano de maíz se correlacionó positivamente con la población final de plantas por hectárea, mayor es la altura de la planta, mayor es la altura de la oídos de primera, menor será el rendimiento. Híbrido simple AG-7000 tiene características deseables para el aumento de la producción de granos en las planicies costeras del Estado de Alagoas