Production and in vitro viability of pollen of peach trees grown in subtropical climate

Abstract

Studies of the production and viability of pollen are very important in breeding programs and for assessing the climatic adaptation of fruit species. The objective of this work was to determine the pollen production per anther and its viability from in vitro germination tests of 16 peach cultivars. The analyses were carried out at the Horticulture Laboratory with vegetable matter from the peach trees in the fruit sector of the Federal Technological University of Paraná, Dois Vizinhos, Paraná State, Brazil. The cultivars used in the research were: Bonão, BR-1, Charme, Chimarrita, Coral, Douradão, Eldorado, Fascínio, Granada, Kampai, Leonense, Marli, Regalo, Riograndense, Rubimel, and Zilli. Pollen production was obtained by counting in a Neubauer chamber. In vitro germination of pollen was obtained after incubation of pollen in culture through a controlled environment (presence of photoperiod and temperature of 25 °C). The experimental design used was completely randomized with four replications. The data were submitted to the Lilliefors normality test and to variance analysis and means comparisons by the Scott-Knott test (α = 0.05). We concluded that the winter conditions of 2016 were better for the development of the buds, which promoted greater production of pollen per anther. The cultivars Douradão, Leonense, Regalo, and Rubimel had the highest rates of pollen viability. The storage of pollen at-20 °C for 60 days reduced its average viability by 42%. Four hours of incubation with photoperiod, is enough to promote the germination of peach pollen. Index terms: Prunus persica L. Batsch, Cultivars, Production and pollen germination, Climatic adaptation.