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/fisiologiaRESUMO
The establishment of minimum growth conditions is essential for in vitro germplasm conservation. Changes to the basic medium and carbon source concentrations are important factors for reducing plant growth in vitro. This study adjusted a protocol for the in vitro conservation of 'Florida Rough' lemon plants. Microcuttings (approximately 1 cm) from plants that were previously cultivated in vitro were inoculated into test tubes with 10 mL of woody plant medium (WPM) at different concentrations (1/1, 1/2 and 1/4) and supplemented with 0, 12.5, 25 and 50 g.L-1 of sucrose, solidified with 7 g.L-1 agar and adjusted to pH 5.8. The experiment was completely randomized in a 3 x 4 factorial design with 15 replications and was maintained under controlled conditions for 360 days. After this period the plant height in cm (PH), the plant dry mass in g (PDM) and the 21 numbers of green leaves (NGL), senescent leaves (NSL) and microcuttings (NM) were evaluated. The variables that best explained the observed behavior of the 'Florida Rough' lemon plants were NGL and PH, with values of 61.63 and 35.08%, respectively. The original concentration of the WPM with the addition of 25 g. L-1 of sucrose yielded the best 'Florida Rough' lemon plant growth reduction in vitro while maintaining the physiologically health of the plants.
O estabelecimento de condições de crescimento mínimo é fundamental para a conservação in vitro de germoplasma. Alterações nas concentrações do meio básico, na fonte de carbono, são fatores importantes na desaceleração do crescimento de plantas in vitro. Este trabalho teve como objetivo ajustar um protocolo de conservação in vitro de plantas do limoeiro 'Rugoso da Flórida'. Microestacas de plantas previamente cultivadas in vitro, com aproximadamente 1 cm, foram inoculadas em tubos de ensaio contendo 10 mL do meio de cultura WPM em diferentes concentrações (1/1, 1/2 e 1/4), suplementado com 0; 12,5; 25 e 50 g.L-1 de sacarose, solidificado com 7 g.L-1 de ágar e o pH ajustado em 5,8. O experimento foi instalado em delineamento inteiramente casualizado com 15 repetições, em esquema fatorial 3 x 4, e mantido sob condições controladas durante 360 dias. Após este período, foram avaliadas altura de planta em cm (AP), número de folhas verdes (NFV), número de folhas senescentes (NFS), número de microestacas (NM) e massa da planta seca em g (MPS). As variáveis que mais contribuíram para explicar a diferença existente no comportamento das plantas do limoeiro 'Rugoso da Flórida' no meio de cultura WPM foram NFV e AP com 61,63 e 35,08%, respectivamente. O meio de cultura WPM na sua concentração original com a adição de 25 g.L-1 de sacarose promoveu os melhores resultados na redução do crescimento das plantas in vitro do limoeiro 'Rugoso da Flórida', mantendo-as fisiologicamente sadias.
Assuntos
Citrus , Folhas de Planta , Banco de Sementes , Técnicas In Vitro , Análise MultivariadaRESUMO
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/fisiologiaRESUMO
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.
RESUMO
Citrus is an extremely important genus in terms of world fruit production. Despite its economic importance and the small genome sizes of its species (2n = 18, 1C = 430 ± 68 Mbp), entire genomic assemblies have only recently become available for some of its representatives. Together with the previous CMA/DAPI banding and fluorescence in situ hybridization (FISH) in the group, these data are important for understanding the complex relationships between its species and for assisting breeding programs. To anchor genomic data with the cytogenetic map of mandarin (Citrus reticulata), the parental species of several economically important hybrids such as sweet orange and clementine, 18 BAC (bacterial artificial chromosome) clones were used. Eleven clementine BACs were positioned by BAC-FISH, doubling the number of chromosome markers so far available for BAC-FISH in citrus. Additionally, six previously mapped BACs were end-sequenced, allowing, together with one BAC previously sequenced, their assignment to scaffolds and the subsequent integration of chromosomes and the genome assembly. This study therefore established correlations between mandarin scaffolds and chromosomes, allowing further structural genomic and comparative study with the sweet orange genome, as well as insights into the chromosomal evolution of the group.
Assuntos
Mapeamento Cromossômico , Citrus/genética , Genoma de Planta , Sequenciamento Completo do Genoma , Sequência de Bases , Cruzamento , Cromossomos Artificiais Bacterianos , Cromossomos de Plantas , Marcadores Genéticos , Hibridização in Situ Fluorescente , Análise de SequênciaRESUMO
This study aimed at evaluating the agronomical performance of 'Pineapple' sweet orange grafted on ten rootstocks, in 2011-2017 harvests, so as to recommend the best combinations to be commercially explored in citrus growing regions in Bahia and Sergipe states, Brazil. An experiment wasinstalled to test ten rootstock for 'pineapple' sweet orange: 'Santa Cruz' Rangpur lime, 'Red Rough' Lemon, 'Orlando' Tangelo, 'Sunki Tropical' Mandarin, 'Swingle' citrumelo, the citrandarins 'Indio' and 'Riverside' and the hybrids HTR-051, LVKxLCR-010 and TSKxCTTR-002. The trial was installed in 2008 in the municipalityof Umbauba in Sergipe. The experimental design was complete randomized blocks with four replications and two plants per plot. Plant spacing was 6 x 4 m which corresponds to 416 plants per hectare and the orchard was rainfed and followed conventional management. The following agronomical parameters were evaluated: vegetative growth, drought tolerance, yield and physico-chemical quality of fruits as well as the abundance of phytophagous mites. Both hybrids LVK x LCR 010 and TSKC x CTTR-002 and the 'Santa Cruz' rangpur lime bestowed higher tolerance to the dry period on the 'Pineapple' orange tree, by comparison with higher water deficit susceptibility conferred by the 'Orlando' tangelo and the 'Swingle' citrumelo. Rootstocks HTR-051, 'Riverside' citrandarin, 'Swingle' citrumelo and TSKC x CTTR-02 induced plants to remain small and, thus, showed aptitude for culture densification. Cumulative yield of the 'Pineapple' orange was higher on rootstocks 'Red Rough' lemon and 'Santa Cruz' Rangpur lime, the hybrid LVK x LCR-010 and 'Sunki Tropical'. Yield efficiency was not influenced by the rootstocks. Physico-chemical quality of fruits of 'Pineapple' orange is affected by the rootstocks and meets the requirements of juice industries. Regarding plant resistance, the rootstocks did not influence the population density of mites P. oleivora, E. banksi and T. mexicanus on 'Pineapple' oranges. Results show that both rootstocks 'Red Rough' lemon and 'Santa Cruz' rangpur lime conferred high regularity to 'Pineapple' orange trees in citrus growing regions in Bahia and Sergipe states
O objetivo deste trabalho foi avaliar o desempenho agronômico da laranjeira 'Pineapple' em combinação com dez porta-enxertos, nas safras 2011-2017, com vistas à recomendação das melhores combinações para exploração comercial na região citrícola dos estados da Bahia e de Sergipe. O experimento consistiu de laranja doce 'pineapple' enxertado nos porta-enxertos limoeiros 'Cravo Santa Cruz', limoeiro 'Rugoso Vermelho', tangeleiro Orlando, tangerineira 'Sunki' Tropical, citrumelo 'Swingle', citrandarins 'Indio', 'Riverside', além dos híbridos HTR 051 e LVK x LCR 010 e 'TSKC x CTTR 002'. O trabalho foi instalado em 2008, no município de Umbaúba, em Sergipe, no delineamento experimental de blocos ao acaso, com quatro repetições, duas plantas por parcela, no espaçamento de 6m x 4m, correspondendo a uma população de 416 plantas· ha-1, com manejo em sistema de produção convencional, sem o uso de irrigação. Os seguintes parâmetros agronômicos foram avaliados: crescimento vegetativo, tolerância à seca, produção e qualidade físico-química de frutos, além da abundância de ácaros fitófagos. Os híbridos LVK x LCR - 010 e TSKC x CTTR - 002, assim como o limoeiro 'Cravo Santa Cruz', conferiram um maior nível de tolerância ao período seco, em contraste com maior suscetibilidade à seca relacionada ao tangelo 'Orlando' e ao citrumelo 'Swingle'. Os porta-enxertos HTR - 051, citrandarin 'Riversidade', citrumelo 'Swingle' e TSKC x CTTR - 002 induziram menor porte às plantas, demonstrando aptidão ao adensamento de plantio. A produção acumulada da laranjeira 'Pineapple' foi maior sobre os porta-enxertos limoeiros 'Rugoso Vermelho' e 'Cravo Santa Cruz', híbrido LVK x LCR - 010 e tangerineira 'Sunki Tropical'. A eficiência produtiva não foi influenciada pelos porta-enxertos. A qualidade física e química de frutos da laranjeira 'Pineapple' foi afetada pelos porta-enxertos e atendeu aos padrões exigidos pela indústria de sucos. Os porta-enxertos estudados não causaram variações nos níveis de populações dos ácaros Phyllocptruta oleivora, Eutetranychus banksi e Tetranychus mexicanus. Com base nos resultados conclui-se que os limoeiros 'Rugoso Vermelho' e 'Cravo Santa Cruz' determinam maior regularidade de produção de frutos à laranjeira 'Pineapple' nas regiões produtoras da Bahia e de Sergipe
Assuntos
Citrus , ÁcarosRESUMO
The objective of this study was to evaluate the ecophysiological behavior of 'Tahiti' acid lime/rootstock grafted on Sunki mandarin hybrids during the prefloration stage of the plants, in the field, under saline stress. The progenies originating from crossings of the 'Sunki' mandarin with 'Rangpur' lime and Poncirus trioliata, as rootstocks, combined with the 'Tahiti' acid lime as a scion. The experiment was carried out under field conditions, at the Federal University of Campina Grande (UFCG), Pombal PB fields. In drainage lysimeter of 150 dm3, studying 10 scion/rootstock combinations, irrigated with two water salinity levels (CEa) (S1 = 0.3 and S2 = 3.0 dS m-1) making a 10 x 2 factorial scheme. The experimental design was a randomized block design, with 3 replicates and each plot consisting of a useful plant, totalizing 60 parcels. The scion/rootstock plants were transplanted at one year of age from the rootstocks sowing, being the beginning of the applications of the saline stress to the 15 days after the transplant lasting until the period of flowering, that is, up to 195 days after transplanting, During this period the plants were analyzed for growth and chlorophyll fluorescence a. The combinations less sensitive to salinity were composed of the 'Tahiti' grafted with TSKFL x (LCR x TR) - 018, TSKFL x TRBK - 011 and TSKFL x TRBK - 030, it being possible to use saline water with up to 3.0 dS m-1 in irrigation. Salinity did not damage the biochemical phase of the scion/rootstock combinations, only affecting the initial fluorescence of the lighted tissue.
Objetivou-se estudar o crescimento e a fluorescência da clorofila a em limeira ácida 'Tahiti' enxertada em híbridos de tangerineira 'Sunki' sob salinidade da água durante a fase de préfloração das plantas. Assim, com base em um delineamento experimental de blocos ao acaso, foram avaliadas dez combinações copa/porta-enxerto, referentes à referida limeira ácida em combinação com dez porta-enxertos (nove híbridos e o limoeiro 'Cravo Santa Cruz' como testemunha), irrigadas com dois níveis de salinidade da água (CEa) (S1=0,3 e S2=3,0 dS m-1), perfazendo um esquema fatorial 10 x 2, que foi repetido em três blocos e com parcela constituída por uma planta útil, totalizando 60 parcelas. As mudas enxertadas foram transplantadas aos 365 dias após a semeadura dos porta-enxertos, em lisímetros de 150 dm3, que foram preenchidos com um Neossolo Flúvico da região, sendo o início das aplicações do estresse salino aos 15 dias após o transplante (DAT), perdurando até o período de floração, ou seja, até os 195 DAT, avaliando o crescimento e a fluorescência da clorofila a. As combinações com maior crescimento quando irrigadas com água de condutividade de 0,3dS-1 foram aquelas com os porta-enxertos TSKC x (LCR x TR) 017, TSKC x (LCR x TR) 012, TSKFL x (LCR x TR) 018, TSKFL x TRBK 011 e TSKFL x TRBK 028. A salinidade não ocasionou dano à fase bioquímica das combinações copa/porta-enxerto, apenas afetado a fluorescência inicial do tecido iluminado. É possível usar água salina de até 3,0 -1 no cultivo de citros, caso se empreguem combinações menos sensíveis, como aquelas tendo como porta-enxertos os híbridos TSKC x (LCR x TR) 017, TSKFL x (LCR x TR) 018, TSKFL x TRBK 011 e TSKFL x TRBK 030.
Assuntos
Citrus , Salinidade , Irrigação Agrícola , Melhoramento VegetalRESUMO
Plant acclimation to recurrent stress involves profound alterations in multiple genetic, metabolic and physiological processes. Stressful conditions usually implicate imbalance in reactive oxygen species (ROS) production and removal rates, which may lead to oxidative stress. However, the primary cellular targets of oxidative stress and their relevance in plant acclimation to abiotic stresses remains poorly characterized. By comparing redox proteomic and sugar profiles in citrus Valencia (VO) scions grafted onto two rootstocks with different soil water extraction capacities - Rangpur Lime (RL) and Sunki Maravilha (SM) - here we demonstrate that both ROS-mediated post-translational protein modification and changes in sugar composition are associated with acclimation to recurrent drought in citrus. The redox proteomic analysis of the distinct scion/rootstock combinations exposed to one (WD1), two (WD2) or three (WD3) water deficit episodes revealed a total of 32 and 55 redox protein spots present in VO/RL and VO/SM plants, respectively. Mass spectrometry analysis of these protein spots revealed essential targets of ROS-mediated posttranslational protein modification in citrus plants challenged by recurrent drought. The oxidation of cysteine thiol groups into glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was shown to increase in WD3 samples of the VO/RL combination, whereas the opposite was observed for the VO/SM combination. Similarly, recurrent drought promoted the oxidation of catalase thiol groups in VO/SM, but not in VO/RL. Carbohydrate profiling revealed that glucose, fructose and galactose may also contribute to the phenotypic differences observed between the citrus genotypes exposed to drought. These findings reveal for the first time that recurrent drought differentially affects the profile of redox proteomics of citrus, suggesting that this alteration may be part of the stress memory in perennial plants.
Assuntos
Citrus/metabolismo , Citrus/fisiologia , Secas , Proteínas de Plantas/metabolismo , Água , Carboidratos/química , Eletroforese em Gel Bidimensional , Oxirredução , Fenótipo , Folhas de Planta/metabolismo , Análise de Componente Principal , Coloração e RotulagemRESUMO
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/métodosRESUMO
In order to study the growth and physiology of citrus rootstocks under saline water irrigation, during formation of rootstocks, an assay was carried out in a factorial scheme, 2 x 6, corresponding to two levels of salinity of the nutrient solution: 0.3 and 4.0 dS m-1 and six genotypes provided by the Citrus Breeding Program of Embrapa Cassava & Fruits-CBP, distributed in randomized block design with three replications. The genotypes were: 1.'Santa Cruz Rangpur' lime (SCRL) (Citrus limonia Osbeck), 2. 'Florida Rough' lemon (FRL) (Citrus jambhiri Lush.), 3. 'Volkamer' lemon (VKL) (C. volkameriana V. Ten. &Pasq.), 4. CSM x SWC- 028, 5. CSM x SWC- 033 and 6.CSM x SWC-041, the last three hybrids of common 'Sunki' mandarin (CSM) [C.sunki (Hayata) hort. ex Tanaka] with 'Swingle' citrumelo (SWC) [C. paradisi Macfad. x Poncirus trifoliata (L.) Raf.]. Nucellar plants from these genotypes were grown in alternative hydroponic system, using Leonard jars. Application of nutrient solution made with saline water started from 90 days after sowing until 120 days, when the growth and physiology parameters of plants were evaluated. Salt stress influenced the growth and physiological parameters in all genotypes. Salt stress did not influence the chlorophyll a fluorescence in the genotypes VKL and CSM x SWC- 041, indicating no damage to the photosynthetic apparatus. The CSM x SWC- 041, 'Santa Cruz Rangpur' lime, 'Florida Rough' lemon and 'Volkamer' lemon are the more tolerant genotypes to salinity based on growth rate.
A fim de estudar o crescimento e a fisiologia de porta-enxertos de citros sob irrigação com água salina, durante a formação de porta-enxertos, realizou-se um ensaio fatorial 2 x 6, correspondente a dois níveis de salinidade da solução nutritiva: 0,3 e 4,0 dS m-1 e seis genótipos fornecidos pelo Programa de Melhoramento de Citros da Embrapa Mandioca & Fruticultura-PMGC, distribuídos em delineamento em blocos casualizados com três repetições. Os genótipos foram: 1. 'limoeiro Cravo Santa Cruz' (LCRSTC) (Citrus limonia Osbeck), 2. 'limoeiro Rugoso da Flórida' (LRF) (Citrus jambhiri Lush.), 3. 'limoeiro Volkameriano' (LVK) (C. Volkameriana V. Ten. & Pasq.), 4. CSM x SWC- 028, 5. CSM x SWC- 033 e 6. CSM x SWC-041, os últimos três híbridos de tangerineira 'Sunki' comum (CSM) [C. sunki (Hayata) hort. Ex Tanaka] com citrumelo 'Swingle' (SWC) [C. Paradisi Macfad. x Poncirus trifoliata (L.) Raf.] Plantas de origem nucelar desses genótipos foram cultivadas em sistema hidropônico alternativo, utilizando vasos Leonard. A aplicação de solução nutritiva feita com água salina iniciou-se a partir de 90 dias após a semeadura até 120 dias, quando foram avaliados os parâmetros de crescimento e fisiologia das plantas. O estresse salino influenciou o crescimento e os parâmetros fisiológicos em todos os genótipos. O estresse salino não influenciou a fluorescência da clorofila a nos genótipos VKL e CSM x SWC-041, indicando não haver danos ao aparelho fotossintético. O CSM x SWC-041, 'limoeiro Cravo Santa Cruz', 'limoeiro Rugoso da Flórida' e 'limoeiro Volkameriano' são os genótipos mais tolerantes à salinidade com base na taxa de crescimento.
Assuntos
Citrus , Salinidade , Irrigação Agrícola , Águas Salinas , Clorofila , FluorescênciaRESUMO
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 , PoncirusRESUMO
High salts concentrations in soil and water are common in semi-arid regions, which reduces the growth and development of crops, especially sensitive plants, such as citrus, being important to identify tolerant materials as well as to study the physiology of these plants. An experiment was conducted evaluate the growth and physiology of citrus trifoliate citrus hybris during their early stage of development (seedling stage) under salt stress conditions. These hydrids were obtained through the Citrus Breeding Program of Embrapa Cassava & Fruits consisting of 'Common sunki' mandarin x 'Argentina' citrange - 019, 'Common sunki' mandarin x ('Rangpur' lime x Poncirus trifoliata) - 040, Trifoliate hybrids - 069, 116 and 127, distributed in a randomized block design with three replications. Nucellar seedlings of the genotypes were grown in an hydroponic system using Leonard jars. The application of nutrient solution with saline water started 90 days after sowing, extending to 120 days, when the seedlings were evaluated for plant growth and physiology. The genotypes common 'Sunki' mandarin x 'Argentina' citrange - 019, Common 'Sunki' mandarin x ('Rangpur' lime x P. trifoliata) - 040 and Trifoliate hybrid - 069 showed the greater tolerance to salinity, while the Trifoliate hybrid - 116 and 127 were found to be the less tolerant.
Altas concentrações de sais no solo e na água são comuns em regiões semiáridas, o que reduz o crescimento e o desenvolvimento das culturas, notadamente as sensíveis, como os citros, sendo importante a identificação de materiais tolerantes assim como o estudo da fisiologia destes. Assim, realizou-se um experimento para avaliar o crescimento e a fisiologia de híbridos de Poncirus trifoliata durante a formação de porta-enxertos sob condições de estresse salino. O experimento foi realizado usando um esquema factorial, 2 x 5, correspondendo a dois níveis de salinidade na solução nutritiva (2,6 e 6,3 dS m-1) e cinco híbridos de citros. Tais híbridos foram obtidos a partir do programa de melhoramento genético de citros da Embrapa Mandioca e Fruticultura, PMG Citrus, a saber: tangerineira 'Sunki Comum' x citrange 'Argentina' 019; tangerineira 'Sunki Comum' x (limoeiro 'Cravo' x Poncirus trifoliata) 040 e os híbrido trifoliados 069, 116 e 127. Os tratamentos foram distribuídos em delineamento experimental de blocos ao acaso, com três repetições. As plantas de origem nucelar dos genótipos foram cultivadas em sistema hidropônico por meio de vasos de Leonard. A aplicação das soluções nutritivas com águas salinas começaram aos 90 dias após a semeadura, se extendendo até os 120 dias, quando as plantas foram avaliadas em relação ao crescimento e a fisiologia. Os genótipos tangerineira 'Sunki Comum' x citrange 'Argentina' - -19, tangerineira Sunki Comum x x (limoeiro 'Cravo' x Poncirus trifoliata) 040 e o híbrido trifoliado 069 tiveram maior tolerância à salinidade, enquanto os híbridos trifoliados 116 e 127 foram os menos tolerantes.
Assuntos
Solos Salitrosos , Citrus/crescimento & desenvolvimento , Salinidade , Melhoramento VegetalRESUMO
The present study evaluated the physiological, molecular and hormonal parameters from scion/rootstock interaction of citrus plants during recurrent water deficit. Responses of the Valencia (VO) scion variety grafted on two rootstocks with different soil water extraction capacities, Rangpur Lime (RL) and Sunki Maravilha (SM), during three successive periods of water deficit: plants exposed to a single episode of water deficit (WD1) and plants exposed to two (WD2) and three (WD3) recurrent periods of WD were compared. The combinations VO/RL and VO/SM presented polymorphic alterations of epigenetic marks and hormonal (i.e. abscisic acid, auxins and salicylicacid) profiles, which were particularly prominent when VO/SM plantswere exposed toWD3 treatment. Upon successive drought events, the VO/SM combination presented acclimatization characteristics that enable higher tolerance to water deficit by increasing transpiration (E), stomatal conductance (g s ) and photosynthetic rate (A), which in turn may have facilitated the whole plant survival. Besides providing comprehensive data on the scion/rootstock interactions upon successive stress events, this study brings the first dataset suggesting that epigenetic alterations in citrus plants triggered by recurrent water deficit lead to improved drought tolerance in this crop species.
Assuntos
Citrus/metabolismo , Secas , Epigênese Genética , Reguladores de Crescimento de Plantas/metabolismo , Estresse Fisiológico/fisiologia , Antioxidantes/metabolismo , Citrus/genética , Metilação de DNA , Desidratação/genética , Desidratação/metabolismo , Regulação da Expressão Gênica de Plantas , Fotossíntese/genética , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Estômatos de Plantas/metabolismo , Transpiração Vegetal/genética , Transpiração Vegetal/fisiologia , Distribuição Aleatória , Estresse Fisiológico/genética , Água/metabolismoRESUMO
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 VegetaisRESUMO
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.
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.
Assuntos
Citrus/fisiologia , Fotossíntese , Solos Salitrosos , Águas Salinas , Fenômenos Fisiológicos Vegetais , Tolerância ao SalRESUMO
Two citrus rootstocks, Rangpur lime (RL) and Sunki Maravilha mandarin (SM), were analyzed either ungrafted or grafted with their reciprocal graft combinations or with shoot scions of two commercial citrus varieties: Valencia orange (VO) and Tahiti acid lime (TAL). All graft combinations were subjected to distinct watering regimes: well-watered, severe drought and rehydration. Growth and water relation parameters, gas exchange as well as sugar and hormone profiles were determined. Data indicated that RL adopted a dehydration avoidance strategy and maintained growth, whereas SM adopted a dehydration tolerance strategy focused on plant survival. Compared with RL, the leaves and roots of SM exhibited higher concentrations of abscisic acid and salicylic acid, which induced drought tolerance, and accumulation of carbohydrates such as trehalose and raffinose, which are important reactive oxygen species scavengers. SM rootstocks were able to transfer their survival strategy to the grafted shoot scions (RL, VO, TAL). Because of their contrasting survival strategies, RL reached the permanent wilting point more quickly than SM whereas SM recovered from prolonged droughts more efficiently than RL. This is one of the most complete studies of drought tolerance mechanisms in citrus crops and is the first to use reciprocal grafting to clarify scion/rootstock interactions.
Assuntos
Citrus/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Estresse Fisiológico , DesidrataçãoRESUMO
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 & histologiaRESUMO
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 & desenvolvimentoRESUMO
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.
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)