Evolution and development of highly derived angiosperm families; vitaceae and cucurbitaceae

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Although great strides have been made in plant development and systematics using the new tools available through molecular techniques, several key questions remain: 1) Are phylogenies (evolutionary relations) based on molecular data in agreement with those derived from more classical morphological data? And if not can the inconsistencies be resolved? 2) What role does or should development, in particular floral development, play in systematics and in reconstructing phylogenetic homologies? and 3) how applicable are current molecular models of floral and vegetative development to highly unorthodox developments such as leaf apposed tendrils (inflorescences) in the grape family (Vitaceae) and the axillary complex (tendril, axillary bud, male and female inflorescence) in the cucumber family (Cucurbitaceae)? The objectives of the proposed research are to address the above questions by focusing on two highly derived angiosperm families; the Vitaceae and the Cucurbitaceae. Our methodology in the proposed research is to look at comparative development and to match our findings with current DNA-based phylogenies. For our developmental studies we plan to use several techniques, including scanning electron microscopy, epi-illumination light microscopy (recently modified by our lab to increase depth of focus), confocal laser microscopy and various histological protocols including paraffin and plastic thick sectioning. Our approach to this research is unique since very few labs have the morphological and developmental databases to allow for extensive comparisons with molecular phylogenies. As well, our goal is to collaborate with labs working with molecular phylogenies and with molecular development in order to build up a combined data set that is fully representative and as complete as possible. The significance of our approach is to bring together as much comparative data as we can, both developmental and molecular, in order to construct a robust phylogeny and also to understand complex evolutionary origins such as the tendril in the Vitaceae.