Viabilidade e conservação de grãos de pólen e polinização artificial de espécies frutíferas nas condições de Roraima

Abstract

Studies of viability and conservation of pollen grains to species of fruit are of fundamental importance, both to inform the conduct of genetic improvement programs, to assist in the definition of the management techniques appropriate to these cultures, especially the pollination, artificial, aiming to ensure not only the increments of productivity, but also better quality of the fruits. In this sense, aimed with this study to assess the viability and conservation of pollen grains and pollination artificial species fruit under the conditions of Roraima. To this end, the work was made up of the following experiments: 1) Study of the opening floral flower sugar apple (Annona squamosa L.), comprising the following steps: observation of the morphological characteristics of the flowers, for 46 hours, aiming at the determination of the following stages: female (anthesis) and male. 2) The feasibility and germination of pollen grains from the minutes submitted to different storage conditions. The experimental design was the entirely randomized, in a scheme factorial 2x7, 2 in the conditions of storage environment (25±2°C and cooled to 5±2°C) and 7 times the wrapping of the pollen grains (0, 4, 8, 12, 16, 20 and 24 hours), with 4 repetitions, for the analysis of the germination of pollen grains and 3 repetitions for the analysis of the viability of the pollen grains, being that each repetition was composed by a blade. The following variables were evaluated: percentage of pollen grains viable and non-viable and the percentage of pollen grains germinated and no germinated. 2) Pollination and artificial quality of the fruiting of sugar apple (Annona squamosa L.) in the conditions of Roraima. The experimental design was entirely randomized, with 8 treatments and 4 repetitions, being 40 flowers per plot. The treatments were composed of the following zones of pollination artificial: 6, 7, 8, 9, 10, 16, 17 and 18 hours. The following variables were evaluated: length and diameter of fruits (cm); firmness of the pulp (N); mass of fresh fruit (g) mass of fresh bark and seeds (g); hydrogen-ionic potential (pH); soluble solids (°Brix) and titratable acidity (g citric acid 100 g-1 of pulp). The variables evaluated in each experiment were subjected to analysis of variance, the effects of the treatments quantitative submitted to the polynomial regression and the qualitative by the test of Tukey at the 5% level of probability. The analyses were performed using the computer program SISVAR. For the climate conditions of the State of Roraima anthesis (stage female) of flowers on the sugar apple begins at 00:00, extending until 12:00 the same day, reaching the stage functionally staminate (male) from 6 o'clock in the morning of the following day. It is recommended that the pollination artificial ateira be held in the mornings, from 6:00 to 10:00. The pollen grains of sugar apple and caçarizeiro remain viable for up to 12 hours after collection stored in the condition of the environment (27±2oC). Key words: Annona squamosa, Amazon, Sugar apple, Biology, floral, Camu-camu, Caçari, Germination, Myrciaria dubia, Improvement.