To support breeding programs of quince tree (Cydonia oblonga Mill.), on the selection of highly productive cultivars, cultivation in subtropical area in Brazil and producers of top quality sweets, the objective of this research was to adjust the growth medium basic to pollen grain germination of this species and quantify the number of stamens, the number of pollen grains per anther and per flower. The pollen used was obtained from anthers of flowers in flask stage of cultivar Portugal. Then, using a brush, the pollen grains were spread on the surface of Petri dishes containing 20 mL of culture medium in accordance with the following experiments:1) Agar concentrations (4, 6, 8 and 10 g L-1) and pH values (3.5; 4.5; 5.5 and 6.5); 2) sucrose concentrations (0, 30, 60 and 90 g L-1); 3) calcium nitrate concentrations (0, 200, 400 and 800 mg L-1); 4) boric acid concentrations (0, 400, 800 and 1200 mg L-1); and emission time of the pollen tube (0, 1, 2, 3, 4, 5 and 6 hours after inoculation), which had been mounted of sequential form. After, the germination rate of pollen grains of 27 quince cultivars (Alaranjado, Alongado, Apple, BA29, Bereckzy, Champion, Cheldow, Constantinopla, CTS 207, Dangers, De Patras, De Vranja, Dulot, Fuller, Mendoza INTA37, Kiakami, Lajeado, Meeck Profilic, Meliforme, Pineapple, Portugal, Provence, Radaelli, Rea's Mamouth,Smyrna, Van Deman and Zuquerineta) was evaluated, and also the number of stamens, the number of pollen grains per anther and per flower. The readings germination percentage should be performed after five hours of incubation and the culture medium to pollen grain germination of quince should be added with 68 g L-1 of sucrose and 366 mg L-1 of boric acid, being the pH measured to 5.8 and the medium solidified with 10 g L-1 of agar. Differences were observed among cultivars germination capacity and the amount of pollen grains, ranging from 37.83% to 82.23% among cultivars, and amount of pollen grains. The pollen grain from the Alaranjado cultivar showed higher germination percentage, and the largest amount of pollen grains per flower.
Cydonia oblonga Mill.; breeding programs; germination rate
