Research in the Miller Lab

		Reproductive ecology of Lobelia (Campanulaceae) Lobelia spicata and L. siphilitica (Campanulaceae) are gynodioecious and populations consist of both hermaphroditic plants and male-sterile plants, although the frequency of male-sterile plants is typically quite low (ca. 10%). In this genus, male-sterility is believed to be under nucleo-cytoplasmic control and all male-sterile plants carry a cytoplasmic male-sterility (cms) mutation (often mitochondrial) and no nuclear restorer. In contrast, hermaphroditic plants either do not have a cytoplasmic male-sterility mutation OR have a cms factor but also have the appropriate nuclear restorer. There are a number of questions in this system students could pursue including the identification of additional populations and a broader analysis of sex ratio variation among populations. In addition, both species are sexually dimorphic and flowers on hermaphroditic plants are larger than those on female (male-sterile) plants; students could examine the nature of the dimorphism and investigate hypotheses put forth to explain sexual dimorphism in gynodioecious taxa. Finally, I am interested in the evolutionary dynamics of cms mutations and nuclear restorer genes in this genus.