POLLEN VIABILITY IN HYBRID SWARM POPULATIONS OF PINUS MUGO × PINUS SYLVESTRIS IN SLOVAKIA pp. 341-348
Authors: (A. Kormutak, B. Vookova, T. Salaj, J.Salaj, V. Èamek, P. Boleèek, P. Maòka, D. Gömöry, Institute of Plant Genetics and Biotechnoogy SAS, Nitra, Slovakia, and others)
Abstract: Pollen viability in three hybrid swarm populations of Pinus mugo × P. sylvestris and in control populations of P. mugo in northern Slovakia was studied throughout two successive years. Germination percentage and pollen tube length were used as the principal parameters of pollen viability. In 2007, a slight reduction of pollen germination was recorded in hybrid swarms on the localities Habovka and Sucha Hora in comparison with the adjoining population of P. mugo from Rohače. Statistically significant differences between individual populations were revealed in pollen tube length only. In 2008, a pollen of improved quality was produced in all the populations tested. Pollen germination of hybrid swarms in Habovka, Sucha Hora and Tisovnica was comparable in the respective year with control population of P. mugo from Vratna valley. At the pollen tube level the hybrid swarms in Habovka and Sucha Hora deviated considerably from control population by their shorter pollen tubes. Obtained results are taken as an evidence supporting partial reduction of pollen viability in the respective hybrid swarms. Annual variation in pollen viability is supposed to be conditioned climatically.