Location: Grape Genetics Research Unit (GGRU)Title: Latent developmental and evolutionary shapes embedded within the grapevine leaf
|CHITWOOD, DAN - Danforth Plant Science Center|
|KLEIN, LAURA - St Louis University|
|O'HANLON, R - St Louis University|
|CHACKO, S - St Louis University|
|GREG, M - St Louis University|
|KITCHEN, C - St Louis University|
|MILLER, ALLISON - St Louis University|
Submitted to: New Phytologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/15/2016
Publication Date: 4/22/2016
Citation: Chitwood, D., Klein, L., O'Hanlon, R., Chacko, S., Greg, M., Kitchen, C., Miller, A., Londo, J.P. 2016. Latent developmental and evolutionary shapes embedded within the grapevine leaf. New Phytologist. 210(1):343-355.
Interpretive Summary: The leaves of plants can have many different shapes and constantly changes shape as the plant grows. Similarly, based on the position of the plant and changes in the environment, plants can produce different shaped leaves. Because leaves can have many different shapes and form in different ways, it may be possible to examine leaf shape and determine the genetic control of this trait. Understanding how to control leaf shape could allow plant breeders to choose and design future varieties that take advantage of leaf shape diversity. We measured over 3200 leaves representing 270 different grapevines, including both wild and cultivated forms. We then used specific landmarks on each leaf (e.g. major veins, lobes) to identify the aspects of leaf shape that are tied to species and tied to position on the vine. These results will be used to compare with differences in leaf shapes detected in mapping populations in order to identify genes and gene markers to be used in future breeding efforts.
Technical Abstract: Across plants, leaves exhibit profound diversity in shape. As a single leaf expands, its shape is in constant flux. Plants may also produce leaves with different shapes at successive nodes. In addition, leaf shape varies among individuals, populations and species as a result of evolutionary processes and environmental influences. Because leaf shape can vary in many different ways, theoretically, the effects of distinct developmental and evolutionary processes are separable, even within the shape of a single leaf. Here, we measured the shapes of > 3200 leaves representing > 270 vines from wild relatives of domesticated grape (Vitis spp.) to determine whether leaf shapes attributable to genetics and development are separable from each other. We isolated latent shapes (multivariate signatures that vary independently from each other) embedded within the overall shape of leaves. These latent shapes can predict developmental stages independent from species identity and vice versa. Shapes predictive of development were then used to stage leaves from 1200 varieties of domesticated grape (Vitis vinifera), revealing that changes in timing underlie leaf shape diversity. Our results indicate that distinct latent shapes combine to produce a composite morphology in leaves, and that developmental and evolutionary contributions to shape vary independently from each other.