Morphology, reserves and pollen viability of some Solanum Sect. Cyphomandropsis species

Abstract

The morphology, energy reserves and viability of three species from Solanum Sect. Cyphomandropsis (Solanum adelphum Morton, S. glaucophyllum Desf. and S. stuckertii Bitter), which grow in Argentina were studied. The pollen grains are tricolporate and their characters are homogeneous. The only differences found among the species were the pollen grain size and the sculpture distribution. The surface features of exine were not readily visible under light microscope, but with SEM the sculpture appeared granulate. Analyses of the cytoplasm of pollen grains show the presence of oils. The average viability was high in two of the studied species (S. adelphum and S. glaucophyllum). An interesting difference was observed between the first and second day flowers of S. stuckertii. The second day flowers had high fertility but those from the first day had a very low fertility. In the latter case, an inner placentoid tissue of the anther hinders pollen release until the entire development is completed. The P/O ratio is linked to the breeding system.