Development Of Pinus Sylvestris L. Male Gametophyte In Urban Environment
L.P. Khlebova, O.V. Bychkova
The peculiarities of the development of the male gametophyte of Pinus silvestris L. in the urban environment were studied. Quality of pollen was evaluated by laboratory experiments through germination at the nutrient medium and by histochemical staining to determine the presence of redox enzymes. It was shown that pollen viability is closely linked to climatic and weather conditions during the period of microsporogenesis and mass pollination. Atmospheric pollution affected the pollen significantly. Low temperatures and high humidity in the background of the weak capacity of self-purification of the atmosphere led to a reduction of the potential pollen viability. The ability of the pollen grains to germinate was reduced, the number of abnormal pollen tubes was increased, and the proportion of cells containing active peroxidase was decreased. We revealed a close positive correlation between the frequency of germinated pollen grains and the presence of active peroxidase, as well as a negative correlation between the percentage of colored pollen and the frequency of pollen tube anomalies, which confirmed the role of peroxidase activity not only in the induction of pollen germination, but also the formation of pollen tubes. A ranking of the urban territory on the strength of unfavorable environmental factors has been carried out. The reaction of male gametophyte of pine allowed us to consider it as a biological indicator of unfavorable ecological situation in the urban environment.