Pegamento de frutos e teores de carboidratos nas folhas de limeiras ácidas Tahiti aneladas e tratadas com ácido giberélico.

• Ano de defesa: 2008
• Autor(a) principal: Pereira, Cassiano Spaziani
• Orientador(a): Siqueira, Dalmo Lopes de
• Banca de defesa: Bruckner, Claudio Horst , Campos, Gustavo de Azevedo
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitotecnia
• Departamento: Plantas daninhas, Alelopatia, Herbicidas e Resíduos; Fisiologia de culturas; Manejo pós-colheita de
• País: BR
• Palavras-chave em Português: Anelamento; Ácido giberélico; Pegamento de fruto
• Palavras-chave em Inglês: Girdling; Gibberellic acid; Fruit onset
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1105

The objective of this work was to evaluate the effect of four concentrations of gibberellic acid and three periods of girdle incisions and girdling of branches on various vegetative characteristics, the carbohydrate contents of the leaves, the onset and production of fruits of the acid lime tree Tahiti . Two experiments were carried out. In the first one, the effect of three periods of girdle incisions and four concentrations of GA3 on the total soluble sugar and starch contents in the leaves, the onset and production of fruit in plants of the acid lime tree Tahiti grown in pots was evaluated. For the variables total soluble sugar and starch contents the design of subdivided plots in time was used, with a factorial 4 x 3 in the plots. As to the variables onset of fruits and number of fruits harvested, the experimental design used was only the 4 x 3 factorial. The first factor was the application of GA3 in four concentrations (0, 7, 14 and 21 mg/L), when 80% of the petals had been abscissed, and the second one, the two periods of girdle incision: one done at the beginning of flowering (IAIF) and the other one month later (IAMAF), plus the control without the girdle incision (SIA). The experimental design was in casualized plots, with five repetitions and two plants per plot. The application of GA3 and the girdling periods did not have an effect on the total soluble sugar contents, on the onset and production of the fruits. An increase of the starch contents in the leaves of the IAMAF plants was observed at 60 days of flowering, but these were not enough to promote an increase in the onset and production of the fruits. In the second experiment, the effect of three periods of girdling of the branches and the application of four concentrations of GA3 on the vegetative growth, on the green colour of the leaves (SPAD index), on the total soluble sugar and starch contents of the leaves, on the onset and production of fruits of the acid lime tree Tahiti grown in the field was evaluated. For the variables height of the plants, green colour of the leaves (SPAD index) and growth of the fruits, the design of plots subdivided in time, with a factorial 4 x 3 in the plot was used. As to the variables onset, production and average weight of the fruits, only the factorial 4 x 3 was used, and the experimental design and their factors were the same used for the first experiment. However, instead of using the girdle incision, the girdling was used on the branches. The total soluble sugar and starch contents were evaluated only in the girdled plants, due to the positive results of this practice on the onset of the fruits, which did not occur on the plants with the GA3 application. It was verified that the periods of girdling and the application of GA3 anticipate the initial growth of the fruits but it did not have any influence on the growth of the fruits until the harvest. The GA3 did not have any effect on other variables. The girdling periods reduced the vegetative growth of the plants and the green colour of the leaves. In the plants girdled at the beginning of the flowering (AIF), the effects were stronger than in those with the girdling done one month after flowering (AMAF). This diffrence was attributed to the better climatic conditions for the healing of the girdled tissues of the AMAF plants, in relation to AIF ones. The AIF and AMAF plants had an increase on the onset of the fruits compared with the SA plants, of 220 and 229%, respectively, and this effect was attributed to the increase of carbohygrates (total soluble sugars and starch) which were observed in the leaves at about 30 days after the girdling practice. The number of fruits harvested were 197 and 259% greater than of the AIF and AMAF plants, respectively, in relation to the AS plants, and the production (weight/plot) of the AIF and AMAF plants, was, respectively, 254 and 265% above those of the SA plants. The greatest onset production caused a reduction of 19 and 8.59% on the average weight of the fruits of the AIF and AMAF plants, respectively, in relation to the SA plants.