Affiliation:
1. Department of Plant Biology, The University of Vermont , 111 Jeffords Hall, 63 Carrigan Drive, Burlington, VT 05405 , USA
Abstract
Abstract
Background and Aims
Pooideae grasses contain some of the world’s most important crop and forage species. Although much work has been conducted on understanding the genetic basis of trait diversification within a few annual Pooideae, comparative studies at the subfamily level are limited by a lack of perennial models outside ‘core’ Pooideae. We argue for development of the perennial non-core genus Melica as an additional model for Pooideae, and provide foundational data regarding the group’s biogeography and history of character evolution.
Methods
Supplementing available ITS and ndhF sequence data, we built a preliminary Bayesian-based Melica phylogeny, and used it to understand how the genus has diversified in relation to geography, climate and trait variation surveyed from various floras. We also determine biomass accumulation under controlled conditions for Melica species collected across different latitudes and compare inflorescence development across two taxa for which whole genome data are forthcoming.
Key Results
Our phylogenetic analyses reveal three strongly supported geographically structured Melica clades that are distinct from previously hypothesized subtribes. Despite less geographical affinity between clades, the two sister ‘Ciliata’ and ‘Imperfecta’ clades segregate from the more phylogenetically distant ‘Nutans’ clade in thermal climate variables and precipitation seasonality, with the ‘Imperfecta’ clade showing the highest levels of trait variation. Growth rates across Melica are positively correlated with latitude of origin. Variation in inflorescence morphology appears to be explained largely through differences in secondary branch distance, phyllotaxy and number of spikelets per secondary branch.
Conclusions
The data presented here and in previous studies suggest that Melica possesses many of the necessary features to be developed as an additional model for Pooideae grasses, including a relatively fast generation time, perenniality, and interesting variation in physiology and morphology. The next step will be to generate a genome-based phylogeny and transformation tools for functional analyses.
Funder
National Science Foundation
National Institute of Food and Agriculture
Publisher
Oxford University Press (OUP)
Reference103 articles.
1. Investigations on some Gramineae from Albania and Greece (chromosome numbers and endophyte infection);Baltisberger;Berichte des Geobotanischen Institutes der Eidgeno¨ssischen Technischen Hochschule Stiftung Ru¨bel,1991
2. Melica;Barkworth,2021
3. Grass inflorescence architecture and meristem determinacy;Bommert;Seminars in Cell and Developmental Biology,2018