Placentation patterns and seed number in fruits of South American Solanum subgen. Leptostemonum (Solanaceae) species

Darwiniana 01/2007; 45(2).
Source: DOAJ


Thirty-seven South American species representing seven sections of Solanum subgen. Leptostemonum were analyzed. Andromonoecious as well as hermaphrodite species were considered. The length and width of their fruits was measured, and the number of seeds per fruit was counted. Medial cross sections of fresh, ripe fruits were observed with a stereoscopic microscope and illustrated. Six placentation patterns and three types of seeds were described. A relationship among seed number, fruit size, fruit color and sexual system was detected by means of statistical analysis. These results suggest that andromonoecy affects fruit size and placentation patterns, in order to contain a higher number of seeds per fruit.

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