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1.
Ciênc. rural (Online) ; 52(1): e20200227, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1286031

Resumo

ABSTRACT: Diversification of rootstock varieties, with consequent reduction in phytosanitary risks, has great importance to the sustainability of citrus cultivation in the south of Brazil. This study evaluated the performance of 42 rootstocks in the nursery phase to generate 'Valencia Late' sweet orange seedlings. Therefore, nucellar seedlings from the rootstocks under study were analyzed in relation to plant height, stem diameter, mortality rate and percentage of bud set after grafting. The experimental design was completely randomized with four replications of 20 sample units. Not adapted genotypes had high mortality rates, and the ones of both hybrids LCR x CTSW - 009 and LVK x LCR - 038 were 100% and 90%, respectively. Other 13 genotypes had mortality rates above 30%, and 'Sunki' mandarin was the female genitor of ten of them. 'Swingle' citrumelo was the rootstock with the highest development (plant height and stem diameter), associated with low mortality rate. In relation to the other rootstocks, the best results were the fast grafting diameter, associated with low mortality rate obtained by hybrids HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, and citrandarins 'Indio', 'Riverside' and 'San Diego', as well as Trifoliate orange and 'Rangpur' lime. In addition to Trifoliate orange, which is widely used in Rio Grande do Sul, these rootstocks have great potential in citriculture in the south of Brazil.


RESUMO: A diversificação do uso de variedades porta-enxerto, com a consequente redução de riscos fitossanitários, é de fundamental importância para a sustentabilidade da citricultura do Sul do Brasil. O objetivo deste trabalho foi avaliar o comportamento de 42 porta-enxertos na formação de mudas de laranjeira 'Valência Late' em fase de viveiro. Nesse sentido, seedlings (plantas oriundas da germinação de sementes) nucelares dos porta-enxertos estudados foram avaliados relativamente aos caracteres altura da planta, diâmetro do caule, taxa de mortalidade e percentagem de pegamento de borbulhas após a enxertia. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 20 unidades amostrais. Genótipos não adaptados tiveram altas taxas de mortalidade, os híbridos LCR x CTSW - 009 e LVK x LCR - 038 apresentaram 100% e 90% de mortalidade, respectivamente. Mais 13 genótipos apresentaram mortalidade superior a 30%, destes, dez têm como parental feminino a tangerineira 'Sunki'. O citrumelo 'Swingle' foi o porta-enxerto que apresentou maior desenvolvimento (altura da planta e diâmetro do caule), associado a uma baixa taxa de mortalidade. Quanto aos demais porta-enxertos, destacaram-se por atingir rapidamente o diâmetro de enxertia, associado a baixa taxa de mortalidade, os híbridos HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, citrandarins 'Indio', 'Riverside' e 'San Diego', assim como o limoeiro 'Cravo' e o Trifoliata. Além do Trifoliata, amplamente utilizado no Rio Grande do Sul, estes porta-enxertos são promissores para a citricultura do Sul do Brasil.

2.
Semina ciênc. agrar ; 43(1): 331-350, jan.-fev. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1368737

Resumo

Proper soil cover management for citrus cultivation can contribute to increased productivity and improved soil quality. This study examined five different vegetative coverings [Urochloa brizantha; U. decumbens, U. ruziziensis, spontaneous vegetation, and herbicide application (glyphosate) in the total area] in the inter rows of a Natal orange orchard [Citrus sinensis (L.) Osbeck] grafted on the Swingle citrumelo (C. paradisi × Poncirus trifoliata). Their effects on the microbiological and chemical attributes of the soil and the vegetative development in the orchard were examined. Chemical (Ca2+, Mg2+, K+, P, pH, H+Al, CECpH7, base saturation, and OM) and microbiological (carbon and nitrogen of microbial biomass, basal respiration, and metabolic quotient) soil attributes in the rows and inter-rows were evaluated for the orchard in 2018 and 2019. There was a significant difference for most variables in the 2 years studied, emphasizing 2019 for microbiological parameters and OM, with the latter being 14.8% lower in the treatment with glyphosate in the total area compared to the treatment with spontaneous vegetation. The results showed the benefits of vegetation cover with brachiaria in inter-rows of the Natal sweet orange orchard in the chemical and microbiological attributes of the soil, especially in carbon and nitrogen of the microbial biomass.(AU)


O manejo adequado da cobertura do solo para o cultivo de citros pode contribuir com o aumento da produtividade e melhoria da qualidade do solo. Esse trabalho estudou cinco diferentes coberturas vegetais (Urochloa brizantha; U. decumbens, U. ruziziensis, vegetação espontânea e aplicação de herbicida (glifosato) em área total) na entrelinha do pomar de laranjeira 'Natal' [Citrus sinensis (L.) Osbeck] enxertada em citrumeleiro 'Swingle' (C. paradisi × Poncirus trifoliata) nos atributos microbiológicos e químicos do solo, bem como a influência desse manejo no desenvolvimento vegetativo do pomar. Foram avaliados os atributos químicos (Ca2+, Mg2+, K+, P, pH, H+Al, CTCpH7 saturação por bases e MO) e microbiológicos (carbono e nitrogênio da biomassa microbiana, respiração basal e quociente metabólico) do solo na linha e na entrelinha do pomar, nos anos de 2018 e 2019. Houve diferença significativa para a maioria das variáveis nos dois anos estudados, com destaque no ano de 2019 para as variáveis microbiológicas e na MO, sendo esse último, 14,8% menor no tratamento com glifosato em área total em relação ao tratamento com vegetação espontânea. Os resultados permitiram evidenciar os benefícios da cobertura vegetal com as braquiárias na entrelinha do pomar de laranjeira doce 'Natal' nos atributos químicos e microbiológicos do solo, sobretudo no carbono e nitrogênio da biomassa microbiana.(AU)


Assuntos
Microbiologia do Solo , Qualidade do Solo , Química do Solo , Brachiaria , Citrus sinensis , Biomassa
3.
Ciênc. rural (Online) ; 52(01): 1-10, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1480283

Resumo

Diversification of rootstock varieties, with consequent reduction in phytosanitary risks, has great importance to the sustainability of citrus cultivation in the south of Brazil. This study evaluated the performance of 42 rootstocks in the nursery phase to generate 'Valencia Late' sweet orange seedlings. Therefore, nucellar seedlings from the rootstocks under study were analyzed in relation to plant height, stem diameter, mortality rate and percentage of bud set after grafting. The experimental design was completely randomized with four replications of 20 sample units. Not adapted genotypes had high mortality rates, and the ones of both hybrids LCR x CTSW - 009 and LVK x LCR - 038 were 100% and 90%, respectively. Other 13 genotypes had mortality rates above 30%, and 'Sunki' mandarin was the female genitor of ten of them. 'Swingle' citrumelo was the rootstock with the highest development (plant height and stem diameter), associated with low mortality rate. In relation to the other rootstocks, the best results were the fast grafting diameter, associated with low mortality rate obtained by hybrids HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, and citrandarins ‘Indio’, ‘Riverside’ and ‘San Diego’, as well as Trifoliate orange and ‘Rangpur’ lime. In addition to Trifoliate orange, which is widely used in Rio Grande do Sul, these rootstocks have great potential in citriculture in the south of Brazil.


A diversificação do uso de variedades porta-enxerto, com a consequente redução de riscos fitossanitários, é de fundamental importância para a sustentabilidade da citricultura do Sul do Brasil. O objetivo deste trabalho foi avaliar o comportamento de 42 porta-enxertos na formação de mudas de laranjeira 'Valência Late' em fase de viveiro. Nesse sentido, seedlings (plantas oriundas da germinação de sementes) nucelares dos porta-enxertos estudados foram avaliados relativamente aos caracteres altura da planta, diâmetro do caule, taxa de mortalidade e percentagem de pegamento de borbulhas após a enxertia. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 20 unidades amostrais. Genótipos não adaptados tiveram altas taxas de mortalidade, os híbridos LCR x CTSW - 009 e LVK x LCR - 038 apresentaram 100% e 90% de mortalidade, respectivamente. Mais 13 genótipos apresentaram mortalidade superior a 30%, destes, dez têm como parental feminino a tangerineira 'Sunki'. O citrumelo 'Swingle' foi o porta-enxerto que apresentou maior desenvolvimento (altura da planta e diâmetro do caule), associado a uma baixa taxa de mortalidade. Quanto aos demais porta-enxertos, destacaram-se por atingir rapidamente o diâmetro de enxertia, associado a baixa taxa de mortalidade, os híbridos HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, citrandarins 'Indio', ‘Riverside’ e ‘San Diego’, assim como o limoeiro 'Cravo' e o Trifoliata. Além do Trifoliata, amplamente utilizado no Rio Grande do Sul, estes porta-enxertos são promissores para a citricultura do Sul do Brasil.


Assuntos
Citrus sinensis/crescimento & desenvolvimento , Citrus sinensis/genética , Germinação/fisiologia
4.
Ci. Rural ; 52(01): 1-10, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-764643

Resumo

Diversification of rootstock varieties, with consequent reduction in phytosanitary risks, has great importance to the sustainability of citrus cultivation in the south of Brazil. This study evaluated the performance of 42 rootstocks in the nursery phase to generate 'Valencia Late' sweet orange seedlings. Therefore, nucellar seedlings from the rootstocks under study were analyzed in relation to plant height, stem diameter, mortality rate and percentage of bud set after grafting. The experimental design was completely randomized with four replications of 20 sample units. Not adapted genotypes had high mortality rates, and the ones of both hybrids LCR x CTSW - 009 and LVK x LCR - 038 were 100% and 90%, respectively. Other 13 genotypes had mortality rates above 30%, and 'Sunki' mandarin was the female genitor of ten of them. 'Swingle' citrumelo was the rootstock with the highest development (plant height and stem diameter), associated with low mortality rate. In relation to the other rootstocks, the best results were the fast grafting diameter, associated with low mortality rate obtained by hybrids HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, and citrandarins ‘Indio, ‘Riverside and ‘San Diego, as well as Trifoliate orange and ‘Rangpur lime. In addition to Trifoliate orange, which is widely used in Rio Grande do Sul, these rootstocks have great potential in citriculture in the south of Brazil.(AU)


A diversificação do uso de variedades porta-enxerto, com a consequente redução de riscos fitossanitários, é de fundamental importância para a sustentabilidade da citricultura do Sul do Brasil. O objetivo deste trabalho foi avaliar o comportamento de 42 porta-enxertos na formação de mudas de laranjeira 'Valência Late' em fase de viveiro. Nesse sentido, seedlings (plantas oriundas da germinação de sementes) nucelares dos porta-enxertos estudados foram avaliados relativamente aos caracteres altura da planta, diâmetro do caule, taxa de mortalidade e percentagem de pegamento de borbulhas após a enxertia. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 20 unidades amostrais. Genótipos não adaptados tiveram altas taxas de mortalidade, os híbridos LCR x CTSW - 009 e LVK x LCR - 038 apresentaram 100% e 90% de mortalidade, respectivamente. Mais 13 genótipos apresentaram mortalidade superior a 30%, destes, dez têm como parental feminino a tangerineira 'Sunki'. O citrumelo 'Swingle' foi o porta-enxerto que apresentou maior desenvolvimento (altura da planta e diâmetro do caule), associado a uma baixa taxa de mortalidade. Quanto aos demais porta-enxertos, destacaram-se por atingir rapidamente o diâmetro de enxertia, associado a baixa taxa de mortalidade, os híbridos HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, citrandarins 'Indio', ‘Riverside e ‘San Diego, assim como o limoeiro 'Cravo' e o Trifoliata. Além do Trifoliata, amplamente utilizado no Rio Grande do Sul, estes porta-enxertos são promissores para a citricultura do Sul do Brasil.(AU)


Assuntos
Citrus sinensis/crescimento & desenvolvimento , Citrus sinensis/genética , Germinação/fisiologia
5.
Sci. agric. ; 75(4)2018.
Artigo em Inglês | VETINDEX | ID: vti-18018

Resumo

ABSTRACT: Rootstocks influence certain characteristics of the scion, such as vigor, fruit yield and quality, and tolerance to biotic and abiotic factors. In conventional citrus breeding programs, hybridization is the main method used for obtaining rootstock varieties. Between Sept and Oct 2006, controlled pollinations were carried out resulting in nine progenies, totaling 461 hybrid seedlings. The female parents were the Santa Cruz Rangpur lime (SCRL) and the Sunki of Florida mandarin (SFM), while the male parents, in addition to this mandarin, were the Indio and Riverside citrandarins, the Thomasville citrangequat (THOM), the Swingle citrumelo, the Argentina citrange (AGC) and the Benecke trifoliate orange (BKTO). Fruit setting rates of these crosses were measured and the hybrids generated were planted in the field in 2008 and evaluated from 2010 to 2014, for the variables of plant mortality, visual vigor, plant height and trunk diameter. The descriptive statistics mean, variation range, coefficient of variation and Pearson skewness coefficient were calculated. Data were submitted to analysis of variance and the means of the treatments were grouped by the Scott-Knott test, both at 5 % significance. The progenies, having the Sunki mandarin as the female parent, presented higher fruit setting rates and lower plant mortality rates than those obtained from the female parent Rangpur lime, while zero plant mortality was observed in the SFM × BKTO cross. The crosses SCRL × SFM, SFM × BKTO, SFM × AGC and SFM × THOM have the potential to generate vigorous hybrids, resulting in rootstock varieties adapted to the landscape unit of Coastal Tableland.

6.
Sci. agric ; 75(4): 339-345, 2018. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497725

Resumo

Rootstocks influence certain characteristics of the scion, such as vigor, fruit yield and quality, and tolerance to biotic and abiotic factors. In conventional citrus breeding programs, hybridization is the main method used for obtaining rootstock varieties. Between Sept and Oct 2006, controlled pollinations were carried out resulting in nine progenies, totaling 461 hybrid seedlings. The female parents were the ‘Santa Cruz Rangpur’ lime (SCRL) and the ‘Sunki of Florida’ mandarin (SFM), while the male parents, in addition to this mandarin, were the ‘Indio’ and ‘Riverside’ citrandarins, the ‘Thomasville’ citrangequat (THOM), the ‘Swingle’ citrumelo, the ‘Argentina’ citrange (AGC) and the ‘Benecke’ trifoliate orange (BKTO). Fruit setting rates of these crosses were measured and the hybrids generated were planted in the field in 2008 and evaluated from 2010 to 2014, for the variables of plant mortality, visual vigor, plant height and trunk diameter. The descriptive statistics mean, variation range, coefficient of variation and Pearson skewness coefficient were calculated. Data were submitted to analysis of variance and the means of the treatments were grouped by the Scott-Knott test, both at 5 % significance. The progenies, having the ‘Sunki’ mandarin as the female parent, presented higher fruit setting rates and lower plant mortality rates than those obtained from the female parent ‘Rangpur’ lime, while zero plant mortality was observed in the SFM × BKTO cross. The crosses SCRL × SFM, SFM × BKTO, SFM × AGC and SFM × THOM have the potential to generate vigorous hybrids, resulting in rootstock varieties adapted to the landscape unit of Coastal Tableland.


Assuntos
Citrus , Hibridização Genética , Melhoramento Vegetal/métodos , Poncirus
7.
Sci. agric. ; 75(4): 339-345, jul.-ago.2018. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-728760

Resumo

Rootstocks influence certain characteristics of the scion, such as vigor, fruit yield and quality, and tolerance to biotic and abiotic factors. In conventional citrus breeding programs, hybridization is the main method used for obtaining rootstock varieties. Between Sept and Oct 2006, controlled pollinations were carried out resulting in nine progenies, totaling 461 hybrid seedlings. The female parents were the ‘Santa Cruz Rangpur lime (SCRL) and the ‘Sunki of Florida mandarin (SFM), while the male parents, in addition to this mandarin, were the ‘Indio and ‘Riverside citrandarins, the ‘Thomasville citrangequat (THOM), the ‘Swingle citrumelo, the ‘Argentina citrange (AGC) and the ‘Benecke trifoliate orange (BKTO). Fruit setting rates of these crosses were measured and the hybrids generated were planted in the field in 2008 and evaluated from 2010 to 2014, for the variables of plant mortality, visual vigor, plant height and trunk diameter. The descriptive statistics mean, variation range, coefficient of variation and Pearson skewness coefficient were calculated. Data were submitted to analysis of variance and the means of the treatments were grouped by the Scott-Knott test, both at 5 % significance. The progenies, having the ‘Sunki mandarin as the female parent, presented higher fruit setting rates and lower plant mortality rates than those obtained from the female parent ‘Rangpur lime, while zero plant mortality was observed in the SFM × BKTO cross. The crosses SCRL × SFM, SFM × BKTO, SFM × AGC and SFM × THOM have the potential to generate vigorous hybrids, resulting in rootstock varieties adapted to the landscape unit of Coastal Tableland.(AU)


Assuntos
Citrus , Poncirus , Hibridização Genética , Melhoramento Vegetal/métodos
8.
Sci. agric ; 74(5): 357-363, Sept.-Oct. 2017. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497666

Resumo

ABSTRACT: Citrus seeds normally have low storability. Identifying an optimal fruit harvest time for production of high vigor seeds is important for nurseries; however, identifying this stage for Swingle citrumelo fruits has been based only on visual color examination, and research related to this parameter has been inconsistent. The main objective of this study was to evaluate a red-green-blue (RGB) color measurement system for successful identification of Swingle citrumelo fruits possessing seeds with maximum physiological potential and storability. Fruits were harvested at three ripening stages identified as green (G), greenish-yellow (GY), and yellow (Y) pericarp, photographed, and the images processed using ImageJ software. Data were expressed as the average pixel value of R, G and B color components and a mean RGB pixel value (R+G+B/3). After harvest, seeds were evaluated for water content, germination, seedling emergence, length, dry mass and vigor as measured by the Seed Vigor Imaging System - SVIS (uniformity and vigor indexes) after 0 and 5 months storage (5 °C and 65 % relative humidity). Percentage of ruptured coat seeds was also evaluated after extraction. The R color component provided the best identification of each G, GY and Y fruits. Seeds extracted from GY fruits had higher storage potential compared with seeds from G and Y fruits. Thus, precise fruit ripening classification can be generated using the RGB color system to identify the best time for harvest to obtain seeds with greater physiological and storage potential.


Assuntos
Citrus paradisi/anatomia & histologia , Citrus paradisi/classificação , Citrus paradisi/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
9.
Sci. agric. ; 74(5): 357-363, Sept.-Oct. 2017. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-15639

Resumo

ABSTRACT: Citrus seeds normally have low storability. Identifying an optimal fruit harvest time for production of high vigor seeds is important for nurseries; however, identifying this stage for Swingle citrumelo fruits has been based only on visual color examination, and research related to this parameter has been inconsistent. The main objective of this study was to evaluate a red-green-blue (RGB) color measurement system for successful identification of Swingle citrumelo fruits possessing seeds with maximum physiological potential and storability. Fruits were harvested at three ripening stages identified as green (G), greenish-yellow (GY), and yellow (Y) pericarp, photographed, and the images processed using ImageJ software. Data were expressed as the average pixel value of R, G and B color components and a mean RGB pixel value (R+G+B/3). After harvest, seeds were evaluated for water content, germination, seedling emergence, length, dry mass and vigor as measured by the Seed Vigor Imaging System - SVIS (uniformity and vigor indexes) after 0 and 5 months storage (5 °C and 65 % relative humidity). Percentage of ruptured coat seeds was also evaluated after extraction. The R color component provided the best identification of each G, GY and Y fruits. Seeds extracted from GY fruits had higher storage potential compared with seeds from G and Y fruits. Thus, precise fruit ripening classification can be generated using the RGB color system to identify the best time for harvest to obtain seeds with greater physiological and storage potential.(AU)


Assuntos
Citrus paradisi/anatomia & histologia , Citrus paradisi/classificação , Citrus paradisi/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
10.
Semina Ci. agr. ; 38(2): 725-738, mar-abr. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-16244

Resumo

Soil and water salinity cause physiological disorders in sensitive plants, such as altered gas exchange in citrus genotypes. However, it is possible to analyse these effects and to identify genotypes tolerant to salt stress. An experiment was carried out in order to evaluate the tolerance of citrus genotypes considering the irrigation with saline water during rootstock formation. The study took place under greenhouse conditions in Pombal county, Paraiba, Brazil. A randomised block design was used, with treatments arranged in a factorial scheme (5 x 8). The two factors were: [i] five salinity levels of irrigation water (0.8, 1.6, 2.4, 3.2 and 4.0 dS m-1) and [ii] eight genotypes of citrus rootstocks: 1. Rangpur Santa Cruz lime (LCRSTC); 2. common Sunki mandarin (TSKC) x Swingle citrumelo (CTSW) - 028; 3. TSKC x CTSW - 033; 4. TSKC x CTSW - 041; 5. Volkamer lemon (LVK) x Rangpur lime (LCR) - 038; 6. Sunki of Florida mandarin (TSKFL); 7. TSKC and 8. Florida rough lemon (LRF). Gas exchange was evaluated at 15, 30 and 60 days after the beginning of the saline water application. High water salinity reduces gas exchange in citrus genotypes, which was more evident at 15 days from the beginning of stress. The genotypes Santa Cruz Rangpur lime, TSKC x CTSW - 041, LVK x LCR - 038 and Florida rough lemon exhibit a satisfactory physiological behaviour during the first 30 days ofexposure to the stress, showing moderate tolerance to salt stress. The genotypes TSKC x CTSW 033 and common ‘Sunki mandarin are the most sensitive to salinity.(AU)


A salinidade do solo e da água ocasionam distúrbios fisiológicos em plantas sensíveis, a exemplo das trocas gasosas em genótipos de citros, podendo-se identificar, a partir dessas variáveis, genótipos tolerantes e a resposta das plantas à salinidade. Assim, objetivou-se avaliar a tolerância de genótipos de citros à salinidade na fase de formação de porta-enxertos. O experimento foi desenvolvido em casa de vegetação, no Município de Pombal, Paraíba, empregando-se o delineamento experimental de blocos casualizados com três repetições e tratamentos arranjados em esquema fatorial, 5x8, relativos à combinação de: [i] cinco níveis de salinidade da água de irrigação (0,8; 1,6; 2,4; 3,2 e 4,0 dS m-1) e [ii] oito genótipos de porta-enxertos de citros: 1. limoeiro Cravo Santa Cruz (LCRSTC); 2. tangerineira Sunki comum (TSKC) x citrumelo Swingle (CTSW) - 028; 3. TSKC x CTSW - 033; 4. TSKC x CTSW - 041; 5. limoeiro Volkameriano (LVK) x limoeiro Cravo (LCR) - 038; 6. tangerineira Sunki da Flórida (TSKFL); 7. TSKC e 8. limoeiro Rugoso da Flórida (LRF). Avaliaram-se as trocas gasosas das plantas aos 15, 30 e 60 dias após o início da aplicação de água salina. A salinidade da água reduziu as trocas gasosas de genótipos de citros, sendo mais evidente aos 15 dias após o início do estresse. Os genótipos limoeiro ‘Cravo Santa Cruz, TSKC x CTSW 041, LVK x LCR 038 e o limoeiro Rugoso da Flórida têm comportamento fisiológico satisfatório durante os primeiros 30 dias de exposição ao estresse, sendo moderadamente tolerantes ao estresse salino. Os genótipos TSKC x CTSW 033 e a tangerineira Sunki Comum são mais sensíveis à salinidade.(AU)


Assuntos
Águas Salinas , Solos Salitrosos , Fotossíntese , Citrus/fisiologia , Tolerância ao Sal , Fenômenos Fisiológicos Vegetais
11.
Ci. Rural ; 46(1)2016.
Artigo em Inglês | VETINDEX | ID: vti-709471

Resumo

Citrus are attacked by pest mites such as the citrus rust mite Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) and the spider mite Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). However, little is known on citrus rootstocks influencing pest mites. We aimed to evaluate the influence of rootstocks on population densities of pest mites on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' throughout time. Adults of both mite species were monthly counted during 19 months from June 2011 to February 2013. Rootstocks influenced the populations of pest mites, since lower densities of P. oleivora were found on 'Pera CNPMF D-6' sweet orange grafted on the hybrid TSKC × CTTR - 002 and on 'Swingle' citrumelo in comparison with the hybrid LVK × LCR - 010, 'Red' rough lime and 'Santa Cruz' rangpur lime as rootstocks. Similarly, lower densities of T. mexicanus were found on 'Valencia Tuxpan' sweet orange grafted on the hybrid HTR-051 in comparison to 'Indio' citrandarin, 'Sunki Tropical' mandarin and LVK × LCR - 010 as rootstocks. We concluded that densities of the mites P. oleivora and T. mexicanus on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' were affected in some periods of the year by some rootstocks, suggesting influence of some genotypes on these pests.


Os citros são atacados por ácaros-praga como o ácaro-da-falsa-ferrugem Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) e Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). No entanto, pouco é conhecido sobre o efeito de porta-enxertos sobre populações de pragas. O objetivo deste trabalho foi avaliar a influência de porta-enxertos nas densidades populacionais de ácaros-praga nas laranjeiras 'Pera CNPMF D-6' e 'Valência Tuxpan' ao longo do tempo. Adultos das espécies de ácaro citadas foram quantificados mensalmente, durante 19 meses, de junho de 2011 a fevereiro de 2013. Os porta-enxertos influenciaram as populações dos ácaros-praga, uma vez que menores densidades de P. oleivora foram encontradas em laranjeira 'Pera CNPMF D-6', enxertada no híbrido TSKC × CTTR - 002 e no citrumelo 'Swingle', em comparação com o que se observou em relação aos porta-enxertos LVK × LCR - 010, limoeiro 'Rugoso vermelho' e limoeiro 'Cravo Santa Cruz'. Similarmente, menores densidades de T. mexicanus ocorreram em laranjeira 'Valência Tuxpan' enxertada no híbrido HTR-051, em comparação com o que se deu em relação aos porta-enxertos citrandarin 'Indio', tangerineira 'Sunki Tropical' e LVK × LCR - 010. Concluiu-se que as densidades dos ácaros P. oleivora e T. mexicanus nas laranjeiras 'Pera CNPMF D-6' e 'Valencia Tuxpan' foram afetadas pelo porta-enxerto em determinados períodos do ano, sugerindo influência de alguns genótipos sobre essas pragas.

12.
Ci. Rural ; 46(1)2016.
Artigo em Inglês | VETINDEX | ID: vti-709446

Resumo

Citrus are attacked by pest mites such as the citrus rust mite Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) and the spider mite Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). However, little is known on citrus rootstocks influencing pest mites. We aimed to evaluate the influence of rootstocks on population densities of pest mites on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' throughout time. Adults of both mite species were monthly counted during 19 months from June 2011 to February 2013. Rootstocks influenced the populations of pest mites, since lower densities of P. oleivora were found on 'Pera CNPMF D-6' sweet orange grafted on the hybrid TSKC × CTTR - 002 and on 'Swingle' citrumelo in comparison with the hybrid LVK × LCR - 010, 'Red' rough lime and 'Santa Cruz' rangpur lime as rootstocks. Similarly, lower densities of T. mexicanus were found on 'Valencia Tuxpan' sweet orange grafted on the hybrid HTR-051 in comparison to 'Indio' citrandarin, 'Sunki Tropical' mandarin and LVK × LCR - 010 as rootstocks. We concluded that densities of the mites P. oleivora and T. mexicanus on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' were affected in some periods of the year by some rootstocks, suggesting influence of some genotypes on these pests.


Os citros são atacados por ácaros-praga como o ácaro-da-falsa-ferrugem Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) e Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). No entanto, pouco é conhecido sobre o efeito de porta-enxertos sobre populações de pragas. O objetivo deste trabalho foi avaliar a influência de porta-enxertos nas densidades populacionais de ácaros-praga nas laranjeiras 'Pera CNPMF D-6' e 'Valência Tuxpan' ao longo do tempo. Adultos das espécies de ácaro citadas foram quantificados mensalmente, durante 19 meses, de junho de 2011 a fevereiro de 2013. Os porta-enxertos influenciaram as populações dos ácaros-praga, uma vez que menores densidades de P. oleivora foram encontradas em laranjeira 'Pera CNPMF D-6', enxertada no híbrido TSKC × CTTR - 002 e no citrumelo 'Swingle', em comparação com o que se observou em relação aos porta-enxertos LVK × LCR - 010, limoeiro 'Rugoso vermelho' e limoeiro 'Cravo Santa Cruz'. Similarmente, menores densidades de T. mexicanus ocorreram em laranjeira 'Valência Tuxpan' enxertada no híbrido HTR-051, em comparação com o que se deu em relação aos porta-enxertos citrandarin 'Indio', tangerineira 'Sunki Tropical' e LVK × LCR - 010. Concluiu-se que as densidades dos ácaros P. oleivora e T. mexicanus nas laranjeiras 'Pera CNPMF D-6' e 'Valencia Tuxpan' foram afetadas pelo porta-enxerto em determinados períodos do ano, sugerindo influência de alguns genótipos sobre essas pragas.

13.
Ci. Rural ; 46(1): 1-6, 2016.
Artigo em Inglês | VETINDEX | ID: vti-379140

Resumo

Citrus are attacked by pest mites such as the citrus rust mite Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) and the spider mite Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). However, little is known on citrus rootstocks influencing pest mites. We aimed to evaluate the influence of rootstocks on population densities of pest mites on the sweet oranges "Pera CNPMF D-6" and "Valencia Tuxpan" throughout time. Adults of both mite species were monthly counted during 19 months from June 2011 to February 2013. Rootstocks influenced the populations of pest mites, since lower densities of P. oleivora were found on "Pera CNPMF D-6" sweet orange grafted on the hybrid TSKC × CTTR - 002 and on "Swingle" citrumelo in comparison with the hybrid LVK × LCR - 010, "Red" rough lime and "Santa Cruz" rangpur lime as rootstocks. Similarly, lower densities of T. mexicanus were found on "Valencia Tuxpan" sweet orange grafted on the hybrid HTR-051 in comparison to "Indio" citrandarin, "Sunki Tropical" mandarin and LVK × LCR - 010 as rootstocks. We concluded that densities of the mites P. oleivora and T. mexicanus on the sweet oranges "Pera CNPMF D-6" and "Valencia Tuxpan" were affected in some periods of the year by some rootstocks, suggesting influence of some genotypes on these pests.(AU)


Os citros são atacados por ácaros-praga como o ácaro-da-falsa-ferrugem Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) e Tetranychus mexicanus (McGregor) (Acari: Tetranychidae). No entanto, pouco é conhecido sobre o efeito de porta-enxertos sobre populações de pragas. O objetivo deste trabalho foi avaliar a influência de porta-enxertos nas densidades populacionais de ácaros-praga nas laranjeiras "Pera CNPMF D-6" e "Valência Tuxpan" ao longo do tempo. Adultos das espécies de ácaro citadas foram quantificados mensalmente, durante 19 meses, de junho de 2011 a fevereiro de 2013. Os porta-enxertos influenciaram as populações dos ácaros-praga, uma vez que menores densidades de P. oleivora foram encontradas em laranjeira "Pera CNPMF D-6", enxertada no híbrido TSKC × CTTR - 002 e no citrumelo "Swingle", em comparação com o que se observou em relação aos porta-enxertos LVK × LCR - 010, limoeiro "Rugoso vermelho" e limoeiro "Cravo Santa Cruz". Similarmente, menores densidades de T. mexicanus ocorreram em laranjeira "Valência Tuxpan" enxertada no híbrido HTR-051, em comparação com o que se deu em relação aos porta-enxertos citrandarin "Indio", tangerineira "Sunki Tropical" e LVK × LCR - 010. Concluiu-se que as densidades dos ácaros P. oleivora e T. mexicanus nas laranjeiras "Pera CNPMF D-6" e "Valencia Tuxpan" foram afetadas pelo porta-enxerto em determinados períodos do ano, suger(AU)


Assuntos
Controle de Ácaros e Carrapatos , Citrus , Genótipo
14.
Sci. agric ; 73(2): 109-114, Mar.-Apr. 2016. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497547

Resumo

Persian lime (PL) [Citrus latifolia (Yu. Tanaka) Tanaka] is an important species both for domestic fresh fruit consumption in Brazil as well as the export market, since the country is one of the largest producers in the world despite the fact that, in commercial plantations, it is still not uncommon to find trees with low productivity and high plant vigor of unknown origin. Selections of Persian lime CNPMF2000, CNPMF2001, CNPMF01, CNPMF02, IAC5, IAC5.1, Bearss, Persian58, and 5059, were therefore grafted onto Swingle citrumelo [C. paradisi Macfad. cv. Duncan × Poncirus trifoliata (L.) Raf.] rootstocks and evaluated in Cruz das Almas, Bahia, Brazil in a field experiment conducted in a completely randomized block design with five replications and two trees per plot. The biometric attributes (canopy height, diameter and volume), yield parameters (yield during the off-season harvest period, yield per plant, production efficiency), and fruit quality traits, were evaluated. The CNPMF2001, CNPMF01, CNPMF02, IAC5, and Bearss selections had 5-11 % shorter trees than the other cultivars. CNPMF01, CNPMF02, Persian58, and 5059 presented higher yield efficiency values, between 3.1-3.4 kg m3, and higher yield levels during the off-season harvest periods. The Bearss, Persian58, CNPMF2000, IAC5.1 and 5059 selections had more acid fruits and the latter three, smaller fruits. Based on their horticultural performance up to eight years of age, CNPMF01, CNPMF02, Persian58 and 5059 selections were the most promising varieties of Persian lime.


Assuntos
Citrus/anatomia & histologia , Citrus/crescimento & desenvolvimento
15.
Sci. agric. ; 73(2): 109-114, Mar.-Apr. 2016. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-30522

Resumo

Persian lime (PL) [Citrus latifolia (Yu. Tanaka) Tanaka] is an important species both for domestic fresh fruit consumption in Brazil as well as the export market, since the country is one of the largest producers in the world despite the fact that, in commercial plantations, it is still not uncommon to find trees with low productivity and high plant vigor of unknown origin. Selections of Persian lime CNPMF2000, CNPMF2001, CNPMF01, CNPMF02, IAC5, IAC5.1, Bearss, Persian58, and 5059, were therefore grafted onto Swingle citrumelo [C. paradisi Macfad. cv. Duncan × Poncirus trifoliata (L.) Raf.] rootstocks and evaluated in Cruz das Almas, Bahia, Brazil in a field experiment conducted in a completely randomized block design with five replications and two trees per plot. The biometric attributes (canopy height, diameter and volume), yield parameters (yield during the off-season harvest period, yield per plant, production efficiency), and fruit quality traits, were evaluated. The CNPMF2001, CNPMF01, CNPMF02, IAC5, and Bearss selections had 5-11 % shorter trees than the other cultivars. CNPMF01, CNPMF02, Persian58, and 5059 presented higher yield efficiency values, between 3.1-3.4 kg m3, and higher yield levels during the off-season harvest periods. The Bearss, Persian58, CNPMF2000, IAC5.1 and 5059 selections had more acid fruits and the latter three, smaller fruits. Based on their horticultural performance up to eight years of age, CNPMF01, CNPMF02, Persian58 and 5059 selections were the most promising varieties of Persian lime.(AU)


Assuntos
Citrus/crescimento & desenvolvimento , Citrus/anatomia & histologia
16.
Sci. agric ; 72(5): 377-384, Sept.-Oct. 2015. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497518

Resumo

The wetted area fraction is a factor critical to the success of drip irrigation. This study aimed to evaluate the effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees. The experiment was carried out in a greenhouse where plants were grown in 0.5 m3boxes internally divided into compartments. The wetting of 12 % of soil area was tested on two types of soil cultivated with Valencia orange trees grafted onto Rangpur lime and Swingle citrumelo rootstocks. Transpiration was determined in 40 plants. Water extraction and root density were evaluated in the compartments. Transpiration is reduced by restriction in wetted soil area, and such reduction is influenced by the number of days after the beginning of partial irrigation, atmospheric evaporative demand and plant phenological stage. Mean transpiration of plants with partial irrigation was equivalent to 84 % of the mean transpiration of plants with 100 % of wetted soil area in the period studied. However, after 156 days of imposing partial irrigation there was no difference in transpiration between treatments. Plant acclimation was caused by an increase in root concentration in the irrigated area. After a period of acclimation, if the entire root system is wetted, soil water extraction becomes proportional to the percentage of wetted area after a short period of time. Despite the reduction in transpiration, there was no difference between treatments with 12 % and 100 % of wetted soil area in terms of vegetative growth.


Assuntos
Citrus sinensis , Irrigação Agrícola , Molhabilidade , Transpiração Vegetal , Umidade do Solo
17.
Sci. agric. ; 72(5): 377-384, Sept.-Oct. 2015. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-28423

Resumo

The wetted area fraction is a factor critical to the success of drip irrigation. This study aimed to evaluate the effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees. The experiment was carried out in a greenhouse where plants were grown in 0.5 m3boxes internally divided into compartments. The wetting of 12 % of soil area was tested on two types of soil cultivated with Valencia orange trees grafted onto Rangpur lime and Swingle citrumelo rootstocks. Transpiration was determined in 40 plants. Water extraction and root density were evaluated in the compartments. Transpiration is reduced by restriction in wetted soil area, and such reduction is influenced by the number of days after the beginning of partial irrigation, atmospheric evaporative demand and plant phenological stage. Mean transpiration of plants with partial irrigation was equivalent to 84 % of the mean transpiration of plants with 100 % of wetted soil area in the period studied. However, after 156 days of imposing partial irrigation there was no difference in transpiration between treatments. Plant acclimation was caused by an increase in root concentration in the irrigated area. After a period of acclimation, if the entire root system is wetted, soil water extraction becomes proportional to the percentage of wetted area after a short period of time. Despite the reduction in transpiration, there was no difference between treatments with 12 % and 100 % of wetted soil area in terms of vegetative growth.(AU)


Assuntos
Citrus sinensis , Umidade do Solo , Transpiração Vegetal , Molhabilidade , Irrigação Agrícola
18.
Ciênc. rural (Online) ; 44(3): 414-417, mar. 2014. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1479555

Resumo

A interenxertia é uma prática que é usada, quando se deseja unir duas plantas que, sabidamente, são incompatíveis, ou quando se pretende diminuir o vigor da cultivar copa. Neste trabalho, avaliou-se uma metodologia alternativa para a produção de mudas de laranjeira Pêra interenxertadas, usando a subenxertia como técnica auxiliar na formação de um interenxerto de limoeiro Cravo. Foram avaliados os seguintes tratamentos: T1 - porta-enxerto trifoliata Flying Dragon (FD) e interenxerto de laranjeira Bahia; T2 - porta-enxerto Citrumeleiro Swingle (CS) e interenxerto de laranjeira Bahia; T3 - porta-enxerto limoeiro Cravo (LC); T4 - porta-enxerto FD e interenxerto de LC; T5 - Porta-enxerto CS e interenxerto de LC. As mudas produzidas no tratamento 4 (Pêra / LC / FD) se aproximaram em vigor das mudas produzidas sem filtro (Pêra / LC). A produção de mudas de laranjeira Pêra interenxertadas pelo sistema tradicional, tendo como porta-enxerto CS ou FD e interenxerto de laranjeira Bahia, não foi possível, em virtude da baixa viabilidade e vigor das brotações.


The interstock is a practice used when to merge two plants that are known to be incompatible or when it is intended to low vigor of the scion. In this study we evaluated an alternative method for the production of Pêra sweet orange nursery trees interstocked, using the technique as inarching assist in forming a interstock of Rangpur Lime (RL). The treatments were: T1 - rootstock trifoliate Flying Dragon (FD) and interstock of sweet orange Bahia, T2 - rootstock Citrumelo Swingle (CS) and interstock of sweet orange Bahia, T3 - rootstock Rangpur Lime (RL); T4 - rootstock FD and interstock RL; T5 - rootstock CS and interstock RL. The sweet orange nursery trees produced in treatment 4 (Pêra / RL / FD) had vigor nearest sweet orange nursery trees produced with interstock (Pêra / RL). The production Pera sweet orange nursery trees interstocked for traditional system, with the rootstock CS or FD and interstock sweet orange Bahia was not possible because of the low viability and vigor of the shoots.


Assuntos
Brotos de Planta , Citrus sinensis
19.
Ci. Rural ; 44(3): 414-417, mar. 2014. tab, ilus
Artigo em Português | VETINDEX | ID: vti-27788

Resumo

A interenxertia é uma prática que é usada, quando se deseja unir duas plantas que, sabidamente, são incompatíveis, ou quando se pretende diminuir o vigor da cultivar copa. Neste trabalho, avaliou-se uma metodologia alternativa para a produção de mudas de laranjeira Pêra interenxertadas, usando a subenxertia como técnica auxiliar na formação de um interenxerto de limoeiro Cravo. Foram avaliados os seguintes tratamentos: T1 - porta-enxerto trifoliata Flying Dragon (FD) e interenxerto de laranjeira Bahia; T2 - porta-enxerto Citrumeleiro Swingle (CS) e interenxerto de laranjeira Bahia; T3 - porta-enxerto limoeiro Cravo (LC); T4 - porta-enxerto FD e interenxerto de LC; T5 - Porta-enxerto CS e interenxerto de LC. As mudas produzidas no tratamento 4 (Pêra / LC / FD) se aproximaram em vigor das mudas produzidas sem filtro (Pêra / LC). A produção de mudas de laranjeira Pêra interenxertadas pelo sistema tradicional, tendo como porta-enxerto CS ou FD e interenxerto de laranjeira Bahia, não foi possível, em virtude da baixa viabilidade e vigor das brotações.(AU)


The interstock is a practice used when to merge two plants that are known to be incompatible or when it is intended to low vigor of the scion. In this study we evaluated an alternative method for the production of Pêra sweet orange nursery trees interstocked, using the technique as inarching assist in forming a interstock of Rangpur Lime (RL). The treatments were: T1 - rootstock trifoliate Flying Dragon (FD) and interstock of sweet orange Bahia, T2 - rootstock Citrumelo Swingle (CS) and interstock of sweet orange Bahia, T3 - rootstock Rangpur Lime (RL); T4 - rootstock FD and interstock RL; T5 - rootstock CS and interstock RL. The sweet orange nursery trees produced in treatment 4 (Pêra / RL / FD) had vigor nearest sweet orange nursery trees produced with interstock (Pêra / RL). The production Pera sweet orange nursery trees interstocked for traditional system, with the rootstock CS or FD and interstock sweet orange Bahia was not possible because of the low viability and vigor of the shoots.(AU)


Assuntos
Brotos de Planta , Citrus sinensis
20.
Ci. Rural ; 44(3): 446-452, mar. 2014. graf, tab
Artigo em Português | VETINDEX | ID: vti-27203

Resumo

O conhecimento do porta-enxerto, do substrato e do recipiente são fundamentais para a definição do período necessário para produzir mudas cítricas de qualidade. O objetivo deste trabalho foi avaliar a emergência de plântulas e o desenvolvimento vegetativo de seis porta-enxertos cítricos, cultivados em dois substratos e mantidos em diferentes recipientes, em sementeira, irrigados por subcapilaridade. Foram testados dois substratos comerciais e a semeadura foi realizada em tubetes com 50cm³, tubetes com 120cm³ e bandejas de isopor contendo 72 células com volume de 120cm³. Os seis porta-enxertos cítricos avaliados foram: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; limoeiro Volkameriano (Citrus volkameriana Pasq.), citrangeiro Fepagro C37 [P. trifoliata x Citrus sinensis [L.] Osbeck.], tangerineira Sunki (C. sunki hort. ex Tan.) e citrumeleiro Swingle (P. trifoliata x C. paradisi). Avaliou-se emergência, altura e diâmetro das plantas ao longo do cultivo em casa de vegetação. Em laboratório, avaliou-se massa fresca e seca da parte aérea e raiz, número de folhas, área foliar por folha e área foliar por planta. Nas avaliações de emergência de plântulas, a tangerineira Sunki, o limoeiro Volkameriano e o citrumeleiro Swingle apresentaram maiores taxas em relação ao Trifoliata, ao citrangeiro Fepagro C 37 e ao Flying Dragon. Ao empregar-se o sistema de irrigação por subcapilaridade, o substrato comercial 1 é recomendado para todos recipientes. O substrato comercial 2 somente deve ser empregado em bandejas alveoladas de 120 cm³.(AU)


In the production of citrus seedling, the knowledge of rootstock substrate and container is essential to define the entire substantial period to produce quality seedling. The objective of this research was to evaluate seedling emergence and vegetative development of six citrus rootstocks grown on two substrates and kept in different containers at the stage of sowing irrigated by capillarity. Two commercial substrates were tested and seeding was performed in three containers: stiff plastic tubes with 50cm³, stiff plastic tubes with 120cm³ and polystyrene trays containing 72 cells with a volume of 120cm³. The six rootstocks citrus evaluated were: Trifoliata [Poncirus trifoliata [L.] Raf.]; Flying Dragon [Poncirus trifoliata (L.) Raf. var. monstrosa]; Volkameriano lemon (Citrus volkameriana Pasq.), Fepagro C37 citrange [P. trifoliata x Citrus sinensis [L.] Osbeck.], Sunki tangerine (C. sunki hort. ex Tan.) and Swingle citrumelo (P. trifoliata x C. paradisi). The emergence, height and diameter of plants in the greenhouse were evaluated. Fresh weight, root and shoot dry weight, leaf number, leaf area per plant and leaf area per leaf were evaluated in the laboratory. In the evaluations of emergence of seedlings, the Sunki tangerine, Volkameriano lemon and Swingle citrumelo had higher rates compared to Trifoliata, Fepagro C37 citrange and Flying Dragon. When the system in a floating irrigation system, commercial substrate 1 is recommended for all containers. The commercial substrate 2 should be only used in alveolate trays of 120cm³.(AU)


Assuntos
Substratos para Tratamento Biológico , Citrus , Irrigação Agrícola , Ação Capilar
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