XVI International Botanical Congess

Androdioecy appears to be a possible explanation for sex expression patterns in Lloydia serotina. Heights of styles and stamens showed a morphological split of flowers into male and hermaphrodite categories. Field pollinations showed males were truly non-functional as maternal parents. Single-flowered individuals can produce male or hermaphrodite flowers, as would be expected with an androdioecious system. L. serotina appears morphologically to be androdioecious, but individuals can change sex between years and so would more accurately be described as either sexually phasic or reduced andromonoecy of some form. Expression patterns are likely influenced by both environmental and internal factors. Male and hermaphrodite plants, as well as nonflowering individuals, were collected from 25 alpine populations and allocation patterns compared with geographic variables, as well as with manipulations of nutrients, water, and herbivory at one site.