RESUMO

O mamoeiro tradicionalmente é propagado por sementes. A propagação assexuada é uma alternativa para a produção de plantas hermafroditas com o padrão de frutos exigidos pelo mercado consumidor. Sendo assim, objetivou-se estudar a propagação vegetativa em mamoeiro hermafrodita ‘Golden, testando o ácido indol-3-butírico (AIB) no enraizamento de miniestacas, em sistema semi-hidropônico. O delineamento experimental utilizado foi o inteiramente casualizado. Os tratamentos consistiram de cinco concentrações de AIB (0, 3, 6, 9 e 12 mg L-1 ), com quatro repetições de seis miniestacas retiradas de plantas hermafroditas em cada parcela. Após 60 dias do cultivo, as miniestacas foram analisadas quanto à porcentagem de enraizamento, porcentagem de sobrevivência, comprimento da maior raiz, e número de folhas. A concentração em torno de 9 mg L-1 de AIB propiciou uma melhor indução ao enraizamento das miniestacas, bem como maior sobrevivência das mudas, formação de folhas e qualidade de suas raízes. Recomenda-se o uso de 9 mg L-1 de AIB no sistema semi-hidropônico de produção de mudas usando miniestacas de mamoeiro ‘Golden hermafrodita.(AU)

Papaya is traditionally propagated by seeds. Asexual propagation is an alternative for the production of hermaphrodite plants, with the fruit pattern required by the consumer market. The objective of this study was to study the vegetative propagation in 'Golden' hermaphrodite papaya, by testing the indole-3-butyric acid (IBA) in the rooting of mini-cuttings in a semi-hydroponic system. The experimental design was completely randomized. The treatments consisted of five concentrations of IBA (0, 3, 6, 9, and 12 mg L-1 ), with four replicates of six mini-cuttings taken from hermaphrodite plants in each plot. After 60 days of cultivation, the mini-cuttings were analyzed for rooting percentage, survival percentage, length of the largest root, and the number of leaves. The concentration around 9 mg L -1 of IBA provided a better induction to the rooting of mini-cuttings, as well as greater seedling survival, leaf formation, and root quality. The use of 9 mg L-1 of IBA in the semi-hydroponic system of seedling production is recommended using 'Golden' hermaphrodite papaya mini-cuttings.(AU)

Assuntos

RESUMO

O mamoeiro tradicionalmente é propagado por sementes. A propagação assexuada é uma alternativa para a produção de plantas hermafroditas com o padrão de frutos exigidos pelo mercado consumidor. Sendo assim, objetivou-se estudar a propagação vegetativa em mamoeiro hermafrodita ‘Golden’, testando o ácido indol-3-butírico (AIB) no enraizamento de miniestacas, em sistema semi-hidropônico. O delineamento experimental utilizado foi o inteiramente casualizado. Os tratamentos consistiram de cinco concentrações de AIB (0, 3, 6, 9 e 12 mg L-1 ), com quatro repetições de seis miniestacas retiradas de plantas hermafroditas em cada parcela. Após 60 dias do cultivo, as miniestacas foram analisadas quanto à porcentagem de enraizamento, porcentagem de sobrevivência, comprimento da maior raiz, e número de folhas. A concentração em torno de 9 mg L-1 de AIB propiciou uma melhor indução ao enraizamento das miniestacas, bem como maior sobrevivência das mudas, formação de folhas e qualidade de suas raízes. Recomenda-se o uso de 9 mg L-1 de AIB no sistema semi-hidropônico de produção de mudas usando miniestacas de mamoeiro ‘Golden’ hermafrodita.

Papaya is traditionally propagated by seeds. Asexual propagation is an alternative for the production of hermaphrodite plants, with the fruit pattern required by the consumer market. The objective of this study was to study the vegetative propagation in 'Golden' hermaphrodite papaya, by testing the indole-3-butyric acid (IBA) in the rooting of mini-cuttings in a semi-hydroponic system. The experimental design was completely randomized. The treatments consisted of five concentrations of IBA (0, 3, 6, 9, and 12 mg L-1 ), with four replicates of six mini-cuttings taken from hermaphrodite plants in each plot. After 60 days of cultivation, the mini-cuttings were analyzed for rooting percentage, survival percentage, length of the largest root, and the number of leaves. The concentration around 9 mg L -1 of IBA provided a better induction to the rooting of mini-cuttings, as well as greater seedling survival, leaf formation, and root quality. The use of 9 mg L-1 of IBA in the semi-hydroponic system of seedling production is recommended using 'Golden' hermaphrodite papaya mini-cuttings.

Assuntos

RESUMO

The selection of superior Carica papaya (L) genotypes depends on the availability of genetic variability and on the favorable and simultaneous response of the genotypes to those traits of most interest. However, manual phenotyping (MP) demands intensive labor, is time-consuming and expensive. The aim of the current study is to access the efficiency of image-based phenotyping (IBP) in estimating genetic parameters and in selecting F4 recombinant inbred lines. The genetic parameters and values were estimated in accordance with the REML/BLUB procedure and combined selection using the selection index based on standardized genetic values. The majority of traits accessed through IBP showed experimental coefficients of variation similar to those found through MP. Both methodologies showed genetic parameters of similar magnitude, indicating expressive genetic variability between lines in the traits accessed in this study. The same superior lines were indicated in both methodologies and expressive genetic gains obtained through the lines were selected for all traits. IBP performance was similar to that of MP with respect to the estimates of breeding-relevant traits such as commercial fruits and yield. Thus, IBP showed efficient phenotypic assessment, as well as selective accuracy in accessing genetic variability and genetic gains, when it was compared to MP. Since IBP is far less dependent on labor, it is expected to be incorporated into the routine of papaya breeding programs as a way of increasing the number of accessed lines and, consequently, increasing genetic gains.(AU)

Assuntos

RESUMO

The selection of superior Carica papaya (L) genotypes depends on the availability of genetic variability and on the favorable and simultaneous response of the genotypes to those traits of most interest. However, manual phenotyping (MP) demands intensive labor, is time-consuming and expensive. The aim of the current study is to access the efficiency of image-based phenotyping (IBP) in estimating genetic parameters and in selecting F4 recombinant inbred lines. The genetic parameters and values were estimated in accordance with the REML/BLUB procedure and combined selection using the selection index based on standardized genetic values. The majority of traits accessed through IBP showed experimental coefficients of variation similar to those found through MP. Both methodologies showed genetic parameters of similar magnitude, indicating expressive genetic variability between lines in the traits accessed in this study. The same superior lines were indicated in both methodologies and expressive genetic gains obtained through the lines were selected for all traits. IBP performance was similar to that of MP with respect to the estimates of breeding-relevant traits such as commercial fruits and yield. Thus, IBP showed efficient phenotypic assessment, as well as selective accuracy in accessing genetic variability and genetic gains, when it was compared to MP. Since IBP is far less dependent on labor, it is expected to be incorporated into the routine of papaya breeding programs as a way of increasing the number of accessed lines and, consequently, increasing genetic gains.

Assuntos

RESUMO

Manual phenotyping for papaya Carica papaya (L) breeding purposes limits the evaluation of a great number of plants and hampers selection of superior genotypes. This study aimed to validate two methodologies for the phenotyping of morpho-agronomic plant traits using image analysis and fruit traits through image processing. In plants of the THB variety and UENF/Caliman-01 hybrid two images (A and B) were analyzed to estimate commercial and irregularly shaped fruits. Image A was also used in the estimation of plant height, stem diameter and the first fruit insertion height. In THB fruits, largest and smallest diameters, length, and volume were estimated by using a caliper and image processing (IP). Volume was obtained by water column displacement (WCD) and by the expression of ellipsoid approximation (EA). Correlations above 0.85 between manual and image measurements were obtained for all traits. The averages of the morpho-agronomic traits, estimated by using images, were similar when compared to the averages measured manually. In addition, the errors of the proposed methodologies were low compared to manual phenotyping. Bland-Altman's approach indicated agreement between the volume estimated by WCD and EA using caliper and IP. The strong association obtained between volume and fruit weight suggests the use of regression to estimate this trait. Thus, the expectation is that image-based phenotyping can be used to expand the experiments, thereby maintaining accuracy and providing greater genetic gains in the selection of superior genotypes.(AU)

Assuntos

RESUMO

Manual phenotyping for papaya Carica papaya (L) breeding purposes limits the evaluation of a great number of plants and hampers selection of superior genotypes. This study aimed to validate two methodologies for the phenotyping of morpho-agronomic plant traits using image analysis and fruit traits through image processing. In plants of the THB variety and UENF/Caliman-01 hybrid two images (A and B) were analyzed to estimate commercial and irregularly shaped fruits. Image A was also used in the estimation of plant height, stem diameter and the first fruit insertion height. In THB fruits, largest and smallest diameters, length, and volume were estimated by using a caliper and image processing (IP). Volume was obtained by water column displacement (WCD) and by the expression of ellipsoid approximation (EA). Correlations above 0.85 between manual and image measurements were obtained for all traits. The averages of the morpho-agronomic traits, estimated by using images, were similar when compared to the averages measured manually. In addition, the errors of the proposed methodologies were low compared to manual phenotyping. Bland-Altman's approach indicated agreement between the volume estimated by WCD and EA using caliper and IP. The strong association obtained between volume and fruit weight suggests the use of regression to estimate this trait. Thus, the expectation is that image-based phenotyping can be used to expand the experiments, thereby maintaining accuracy and providing greater genetic gains in the selection of superior genotypes.

Assuntos

RESUMO

A resistência genética constitui alternativa sustentável para o controle da mancha-de-phoma na cultura do mamoeiro. No entanto, estudos básicos são necessários para a escolha de genitores e combinações híbridas resistentes à doença. Neste trabalho, por meio de cruzamento dialélico, envolvendo oito genótipos de mamão, quatro do grupo Solo e quatro do grupo Formosa, estimou-se a capacidade geral e específica de combinações híbridas quanto à resistência a mancha-de-phoma. Os genitores, bem com os híbridos obtidos dos cruzamentos foram avaliados em blocos casualizados, com quatro repetições. Quantificaram-se em duas épocas, março e maio de 2010, as severidades de mancha-de-phoma em folha, com auxílio de escala diagramática. Os genótipos Maradol JS12-N, Sekati e São Mateus demonstram melhor capacidade geral de combinação. Os híbridos Maradol x Golden, Maradol x Sunrise Solo 72/12, JS12-N x Golden, JS12-4 x Waimanalo, Sekati x Waimanalo, Waimanalo x Golden, Waimanalo x São Mateus, Golden x Sunrise Solo 72/12 e Golden x São Mateus apresentaram resultados promissores para seleção quanto à resistência à doença, com valores negativos de capacidade específica de combinação para severidade de mancha-de-phoma.

Genetic resistance represents a viable alternative to control phoma-spot in papaya crop. However, basic studies are necessary to base the choice of genitors and hybrid combinations disease resistant. In this research, a diallel cross was conducted involving eight genotypes of papaya, four of the Solo group and four of Formosa group and it was estimated general and specific abilities of combination for the phoma-spot resistance. The treatments were evaluated in a randomized block design with four replications. The severity of phoma-spot in leaves was quantified in two ocasions: March and May of 2010. The genotypes Maradol JS12-N, Sekati e São Mateus show better general combining ability. The hybrids Maradol x Golden, Maradol x Sunrise Solo 72/12, JS12-N x Golden, JS12-4 x Waimanalo, Sekati x Waimanalo, Waimanalo x Golden, Waimanalo x São Mateus, Golden x Sunrise Solo 72/12 and Golden x São Mateus showed promising results for selection, with negatives values of specific combining ability for severity of phoma spot.