Breeding System, Sex Ratio and Individual Size of the Gynodioecious Nototriche compacta (Malvaceae) in the Andes of Central Chile

Abstract

Abstract Nototriche compacts (Malvaceae) is a gynodioecious endemic species distributed along the Andes, Chile. We studied the breeding system, sex ratio and individual size in two populations localized in Cerro Franciscano in the Andes of Central Chile (33°19′ S and 70°16′ W, elevation 3400–3470 m). In both populations we compared sex characteristics and flower life span; counted the number of both morphs and sterile individuals, and their size; and made compatibility tests in both morphs, quantifying fruit number, number of non‐fertilized and fertilized ovules and aborted seeds. Both morphs have a similar flower life and morphology; however, females have more stamens and have a wider calyx and petals. The number of hermaphrodites was significantly higher in both populations; although in upper populations (UP) the difference was minor. Females are larger in size than hermaphrodites in both populations but not significantly. Except for the apomixis test, all female and hermaphrodite individuals used in the other tests produced fruits; however, in both populations open‐pollinated female and hand‐pollinated hermaphrodite individuals produced fewer fruits than manipulated and non‐manipulated individuals, respectively. Analysis of developed seeds and unfertilized ovule shows morph differences between treatments within and between populations. Results suggest that N. compacta is selfing and crossing, but in the studied populations each morph has a different genetic contribution.