Ecological features of flowers and the amount of pollen released in Corylus avellana (L.) and Alnus glutinosa (L.) Gaertn.

Abstract

Hazel and alder bloom as one of the first plants in climatic conditions of Poland. In the present study, detailed observations were made of the structure of flowers of Corylus avellana L. and Alnus glutinosa (L.) Gaertn. Pollen yield of the abovementioned species was determined. The number of pollen grains in the theca, anther, flower and inflorescence was calculated. A comparison was made of the number of pollen grains of these taxa recorded during the atmospheric pollen seasons analysed over a period of 8 years in the conditions of Lublin. The study demonstrates that pollen yield of the common hazel inflorescence was 66 mg, whereas for black alder it was 120 mg. It was found that the number of pollen grains produced by the alder inflorescence was 2.2 times higher than by the hazel inflorescence. The atmospheric pollen season of the studied plant taxa was recorded at similar dates, but alder pollen was in much larger concentrations.