Fig. 2
From: The strong competitive role of 2n pollen in several polyploidy hybridizations in Rosa hybrida
The morphological characteristics and germination of natural 1n pollen and 2n pollen of ‘Old Blush’. a Activity of natural 1n pollen and 2n pollen of ‘Old Blush’, stained by Alexandria dye, in which blue dye suggests pollen inactivity and red shows active generation. b In vitro germination of ‘Old Blush’ pollen. c-f. The morphological characteristics of pollen grains of ‘Old Blush’ under SEM. c Equatorial view. d Polar view. e Exine ornamentation. f 2n and 1n pollen. g Determination threshold of 1n and 2n of pollen grains diameter and pollen tube width. r (diameter, and width) = 0.97. bar A,B = 30 μm