The Effect of Air Pollution on Developmental Stages and Pollen Germination, Pollen Tube Growth and Fruit Set of the Apple Cultivars ‘Golden Delicious’ and ‘Golab’; [Die Auswirkungen der Luftverschmutzung auf die Entwicklungsstadien und die Pollenkeimung, das Pollenschlauchwachstum und den Fruchtansatz der Apfelsorten ‘Golden Delicious’ und ‘Golab’]

In this study, the effect of industrial air pollution on developmental stages and pollen germination, pollen tube growth and fruit set of the apple cultivars ‘Golden Delicious’ and ‘Golab’ was studied. For this purpose, the flowers of the apple cultivars used were collected in early spring among the trees of the same age from Astaneh region as the non-polluted region, the region around the refinery as the semi-polluted region, and the Gavar region as the polluted region. The results of the variance analysis showed that the highest rate of pollen germination and pollen tube growth was associated with ‘Golden Delicious’ cultivar in Astaneh region; while, the lowest rate was related to the ‘Golab’ cultivar in Gavar region. The least amount of fruit set was related to pollen grains belonging to Gavar and refinery regions, whereas pollen grains from Astaneh region led to the highest amount of fruit set. Evaluation of the developmental stages of the anthers and pollen grains by light microscopy and SEM images of pollen grains showed that pollen grains from trees in polluted regions lost their normal forms and developed wrinkles. The results indicated that the effect of pollution on production of pollen grains with abnormal shape in the ‘Golab’ cultivar was more than the ‘Golden Delicious’ cultivar. Therefore, it is recommended for areas with air pollution to cultivate ‘Golden Delicious’ instead of ‘Golab’. © 2019, Springer-Verlag GmbH Deutschland, ein Teil von Springer Nature.