INFLUENCE OF THE TEMPERATURE IN GERMINATION OF SEEDS OF JABUTICABA TREE

The jaboticaba tree (Myrciaria spp.) is originated from the center-south of Brazil and presents different types. It’s a medium size tree, with tendency to form a crown with great number of branches. A characteristic considered as limitant for the commercial crop is the great juvenility, advicing producing good rootstocks of seedlings and graft wanted varieties, and other vegetative processes. With the purpose of evaluating the effect of temperature on germination of three clones of jaboticaba tree, was carried out a laboratorial research. It was observed influence of the temperature on germination. The highest percentage of germination was obtained at low temperature (15oC and 20oC). When it was used the temperature of 35oC, two clones had only 8% of germination, while the other one was verified 35%. These values show the possibility of the ocurrence of variability among the clones of jaboticaba tree.


INFLUENCE OF THE TEMPERATURE IN GERMINATION OF SEEDS OF JABUTICABA TREE 1
RENATA APARECIDA DE ANDRADE 2 & ANTONIO BALDO GERALDO MARTINS 3 ABSTRACT -The jaboticaba tree (Myrciaria spp.) is originated from the center-south of Brazil and presents different types.It's a medium size tree, with tendency to form a crown with great number of branches.A characteristic considered as limitant for the commercial crop is the great juvenility, advicing producing good rootstocks of seedlings and graft wanted varieties, and other vegetative processes.With the purpose of evaluating the effect of temperature on germination of three clones of jaboticaba tree, was carried out a laboratorial research.It was observed influence of the temperature on germination.The highest percentage of germination was obtained at low temperature (15 º C and 20 º C).When it was used the temperature of 35ºC, two clones had only 8% of germination, while the other one was verified 35%.These values show the possibility of the ocurrence of variability among the clones of jaboticaba tree.Index terms: Myrciaria spp.; seeds; germination.
According to Andersen & Andersen (1989), for propagation of the jaboticaba tree is more used the seedlings, however, an grafting can result in more than 75% of cathing.
A characteristic considered as limitant for the commercial culture of the jaboticaba tree is the great juvenility period of the plant, being necessary to produce good rootstocks of seedlings and graft the wanted varieties, or still multiplying for other vegetative processes.For the rootstocks formation is necessary about 1 year and to obtain a seedling in production are necessary approximately 10 years.The value of a jaboticaba tree seedling, in production is nearly R$70,00.
The objective of this research was to evaluate the effect of the temperature in the germination of jaboticaba seeds.
The experiment was carried out at the Laboratory of Seeds, located in the Department of Vegetable Production of "Faculdade de Ciências Agrárias e Veterinárias -UNESP -Campus of Jaboticabal/SP".
The treatments were constituted by five temperatures: 15 º C, 20 º C, 25 º C, 30 º C and 35 º C, being used three jaboticaba clones, four repetitions and 10 seeds by repetition.The clones were chosen randomized in an orchard with about 157 jaboticaba trees, originated of seeds, located at "Faculdade de Ciências Agrárias e Veterinárias".The differences among the selected plants were observed visually, such as: carry of the tree; format of the cup; size and aspect of the leaves; coloration of the new buds; size, forms and coloration of the fruits and size of the seeds.
The seeds were extracted of ripe fruits, washed and placed to drying in to the atmosphere for 24 hours; after this, they were placed in gerbox, having as substrate fine vermiculite and maintained at germinator.Was evaluated the number of seeds germinated for 3 months, and the values were later transformed in percentage for accomplishment of statistical analysis.For seed germination was considered the emition of the primary root.The obtained values were analyzed through the test of Tukey, to the 5% of probability.
When talk about tropical fruits, as the case of the jaboticaba tree, it's waited almost that instinctively, that the best temperatures for the germination of your seeds to be in a strip between 25 and 30ºC, once the production of fruits, for the local conditions, felt in October, in other words, in the middle of the summer.However, by the data analysis was observed that, in a general way, was at 15ºC where happened the largest germination percentages (Figure 1), not differing significantly, however, of the temperature of 20ºC; as was increased the temperatures a corresponding diminish was observed in the germination.When were used temperatures of 25 and 30ºC was verified that just about 50% of the seeds germinated and can considered that the worst results were the obtained for the seeds exposeds to the temperature of 35ºC.
COMUNICAÇÃO CIENTÍFICA FIGURE 1-Influence of the temperature in the seed germination of jaboticaba tree.
tively of 40 and 34%, while for jaboticaba tree, in this strip was obtained a value near to 50% (Table 1).