Fusão de protoplastos com microprotoplastos irradiados como ferramenta para painel híbrido de radiação em citros

The objective of this work was to combine asymmetric somatic hybridization (donor-recipient fusion or gamma fusion) to microprotoplast-mediated chromosome transfer, as a tool to be used for chromosome mapping in Citrus. Swinglea glutinosa microprotoplasts were irradiated either with 50, 70, 100 or 200 gamma rays and fused to cv. Ruby Red grapefruit or Murcott tangor protoplasts. Cell colonies were successfully formed and AFLP analyses confirmed presence of S. glutinosa in both 'Murcott' tangor and 'Ruby Red' grapefruit genomes.O objetivo deste trabalho foi combinar hibridação somática assimétrica (fusão doador-recipiente ou fusão gama) e transferência cromossômica mediada por microprotoplastos como uma ferramenta para o mapeamento cromossômico em Citrus. Microprotoplastos de Swinglea glutinosa foram irradiados com doses de 50, 70, 100 ou 200 raios gama e fusionados com protoplastos de pomelo cv. Ruby Red ou de tangor Murcott. Houve sucesso na formação de colônias de células, e a análise AFLP confirmou a presença de S. glutinosa nos genomas do tangor 'Murcott' e do pomelo 'Ruby Red'

Grapefruit tree named 'TR-1'

The new grapefruit 'TR-1' is provided. The variety is produced from a mutation of 'Rio Red' grapefruit, which can be distinguished by its outstanding features. TR-1 is a red grapefruit variety originated as a budsport mutation from Rio Red grapefruit and differentiating from the Rio Red grapefruit by a Red external color contrasting to the yellow with red blush from Rio Red grapefruit. The internal color is red with milder flavor reduced bitter taste.U

Fusion of protoplasts with irradiated microprotoplasts as a tool for radiation hybrid panel in citrus

The objective of this work was to combine asymmetric somatic hybridization (donor-recipient fusion or gamma fusion) to microprotoplast-mediated chromosome transfer, as a tool to be used for chromosome mapping in Citrus. Swinglea glutinosa microprotoplasts were irradiated either with 50, 70, 100 or 200 gamma rays and fused to cv. Ruby Red grapefruit or Murcott tangor protoplasts. Cell colonies were successfully formed and AFLP analyses confirmed presence of S. glutinosa in both 'Murcott' tangor and 'Ruby Red' grapefruit genomes

Citrus asymmetric somatic hybrids produced via fusion of gamma-irradiated and iodoacetamide-treated protoplasts Híbridos somáticos assimétricos de citros produzidos pela fusão de protoplastos irradiados e tratados com iodoacetamida

The objective of this study was to produce citrus somatic asymmetric hybrids by fusing gamma-irradiated protoplasts with iodoacetamide-treated protoplasts. Protoplasts were isolated from embryogenic suspension cells of grapefruit (Citrus paradisi Macfad.) cultivars Ruby Red and Flame, sweet oranges (C. sinensis Osbeck) 'Itaboraí', 'Natal', Valencia', and 'Succari', from 'Satsuma' (C. unshiu Marcow.) and 'Changsha' mandarin (C. reticulata Blanco) and 'Murcott' tangor (C. reticulata x C. sinensis). Donor protoplasts were exposed to gamma rays and receptor protoplasts were treated with 3 mmol L-1 iodoacetamide (IOA), and then they were fused for asymmetric hybridization. Asymmetric embryos were germinated, and the resulting shoots were either grafted onto sour orange, rough lemon or 'Swingle' (C. paradisi x Poncirus trifoliata) x 'Sunki' mandarin rootstock seedlings, or rooted after dipping their bases in indol-butyric acid (IBA) solution. The products were later acclimatized to greenhouse conditions. Ploidy was analyzed by flow cytometry, and hybridity was confirmed by amplified fragment length polymorphism (AFLP) analysis of plantlet DNAsamples. The best treatment was the donor-recipient fusion combination of 80 Gy-irradiated 'Ruby Red' protoplasts with 20 min IOA-treated 'Succari' protoplasts. Tetraploid and aneuploid plants were produced. Rooting recalcitrance was solved by dipping shoots' stems in 3,000 mg L-1 IBA solution for 10 min.O objetivo deste trabalho foi produzir híbridos somáticos assimétricos de citros pela fusão de protoplastos irradiados com raios gama e protoplastos tratados com iodoacetamida. Protoplastos foram isolados de suspensões celulares embriogênicas de pomelo (Citrus paradisi Macfad.), cultivares Ruby Red e Flame, de laranja doce (C. sinensis Osbeck) 'Itaboraí', 'Natal', Valencia' e 'Succari', de tangerinas 'Satsuma' (C. unshiu Marcow.) e 'Changsha' (C. reticulata Blanco) e de tangor 'Murcott' (C. reticulata x C. sinensis). Protoplastos doadores foram expostos a raios gama e protoplastos receptores foram tratados com 3 mmol L-1 de iodoacetamida (IOA) e fusionados para hibridação assimétrica. Embriões assimétricos foram germinados e as brotações produzidas foram enxertadas sobre porta-enxertos de sementes de 'Laranja azeda', 'Limão rugoso' ou citrumelo 'Swingle' (C. paradisi x Poncirus trifoliata) x 'Sunki' ou enraizadas após embebição em solução de ácido indol-3-butírico (IBA) e aclimatadas em casa de vegetação. A análise de ploidia foi realizada por meio de citometria de fluxo e a hibridicidade foi confirmada por análise de polimorfismo de comprimento de fragmentos amplificados (AFLP) de amostras de DNA das plântulas. A melhor combinação doador-recipiente foi de protoplastos de 'Ruby Red' irradiados com 80 Gy, fusionados com protoplastos de 'Succari' tratados por 20 min com IOA. Plantas tetraploides e aneuploides foram produzidas e o problema de recalcitrância ao enraizamento foi resolvido pela introdução das bases das brotações em 3.000 mg L-1 de IBA por 10 min