How Do Pollen Grains of Convallaria majalis L. Respond to Different Habitat Conditions?

To date, the effect of habitat conditions on the characteristics of pollen has not been extensively investigated; however, it needs to be remembered that it may be highly significant for the quality of their generative reproduction success. It was decided to conduct the analyses on Convallaria majalis as a common species, naturally found in many different forest habitats. Moreover, the investigations covered pollen morphology and for the first time also the variability of pollen grains in this species. The plant material came from 98 natural sites located in Poland, in nine differing forest habitats. In total, 2940 pollen grains were analyzed in terms of five quantitative features (i.e., the length of the longest and shortest polar axes-LA and SA, exine thickness-Ex, the LA/SA and Ex/LA ratios) as well as the following qualitative ones: pollen outline and shape, sulcus type and exine ornamentation. Our studies revealed that the most important pollen characteristics in C. majalis included sulcus type, exine ornamentation, distribution and size of perforations, LA and pollen shape. The study showed the response of pollen to different habitat conditions found in the nine investigated habitats. The Ex/LA ratio and Ex were these pollen characteristics, which exhibited the most marked response to the different habitat conditions. Pollen from two habitats, moist mixed coniferous forest and upland mesic broadleaved forest, exhibited the most distinct characteristics.

Automated summary

The effect of habitat conditions on the characteristics of pollen in Convallaria majalis, a common species found in different forest habitats, was investigated. Quantitative and qualitative features of pollen grains were analyzed from 2940 samples collected from 98 natural sites in Poland. The study showed that sulcus type, exine ornamentation, distribution and size of perforations, LA, and pollen shape were the most important characteristics in C. majalis pollen. The response of pollen to different habitat conditions was observed, with the most distinct characteristics found in moist mixed coniferous forest and upland mesic broadleaved forest habitats.