Stage heterogeneity of generative and vegetative cells in pollen grains of dehiscent anthers of two cultivars ofMalus domestica Borkh: ?Golden Delicious? and ?Starkrimson?

Abstract

Pollen grains of dehiscent anthers of two cultivars ofMalus domestica “Golden Delicious” (partially self-incompatible) and “Starkrimson” (self-incompatible) were studied by Feulgen cytophotometry and starch staining. The collected results show: I) in both cultivars generative cells in G1 (DNA content/nucleus 1 c) and in G2 (DNA content/nucleus 2 c) are present; II) in both cultivars vegetative cells may be characterized by the lack of starch, or by its presence in variable amount; III) when single pollen grains are considered, G1 and G2 generative cells can be present in concomitance with starch free or with starch containing vegetative cells.