Dr Ilia J Leitch

Assistant Head of Comparative Plant and Fungal Biology Department and Senior Research Leader


Comparative Plant and Fungal Biology (CPFB)


Character Evolution


Genome size, chromosomes, polyploidy, Nitrogen and Phosphorus, flow cytometry

Biography Plus

I lead a team of Kew scientists investigating character evolution in plants. We conduct research aimed at identifying and understanding (i) how different plant traits interact and evolve to generate the diversity of plant life, and (ii) how key characters influence, or are influenced by, global environmental change. The particular characters currently under study range across all levels of plant organization from the genomic to the whole plant level.

My own research is focused on genomic characters such as genome size, chromosome organization, and DNA repeats (see project: Uncovering the genomic diversity of plants) to (i) understand the origin, evolution and biological significance of the immense diversity of genomic characters across land plants, and (ii) determine how these characters impact at the whole plant level to influence how, when, and where plants grow and respond to global change.

I am also involved in the Plant and Fungal Trees of Life strategic 2020 output and collate genome size data for the Plant DNA C-values database.

The Plant DNA C-values database comprises the most comprehensive compilation of genome size data for land plants and algae available on the internet. The latest release 7.1 (April 2019) contains data for over 12,000 species.

Qualifications and appointments Plus
  • BSc (Hons), Univ. Bristol, 1985
  • PhD, Univ. Bristol, 1990
Selected publications Plus

Guignard, M.S., Crawley, M.J., Kovalenko, D., Nichols, R.A., Trimmer, M., Leitch, A.R. & Leitch, I.J. (2019).

Interactions between plant genome size, nutrients and herbivory by rabbits, molluscs and insects on a temperate grassland.

Proceedings of the Royal Society B: Biological Sciences 286: 20182619.  

Hidalgo, O., Pellicer, J., Christenhusz, M.J.M., Schneider, H., Leitch, A.R. & Leitch, I.J. (2017)

Is there an upper limit to genome size?

Trends in Plant Science 22: 567-573

Guignard, M.S., Nichols, R.A., Knell, R.J., Macdonald, A., Romila, C-A., Trimmer, M., Leitch, I.J. & Leitch, A.R. (2016)

Genome size and ploidy influence angiosperm species' biomass under nitrogen and phosphorus limitation.

New Phytologist 210: 1195-1206. 

Ma, L., Hatlen, A., Kelly, L.J., Becher, H., Wang, W., Kovarik, A.R., Leitch, I.J., Leitch, A.R. (2015)

Angiosperms are unique among land plant lineages in the occurrence of key genes in the RNA-directed DNA Methylation (RdDM) pathway.

Genome Biology and Evolution 7: 2648-2662.

Dodsworth, S., Leitch, A.R. & Leitch, I.J. (2015)

Genome size diversity in angiosperms and its influence on gene space.

Current Opinion in Genetics & Development 35: 73-78. 

Kelly, L.J., Renny-Byfield, S., Pellicer, J., Macas, .J, Novák, P., Neumann, P., Lysak, M.A., Day, P.D., Berger, M., Fay, M.F., Nichols, R.A., Leitch, A.R. & Leitch, I.J. (2015)

Analysis of the giant genomes of Fritillaria (Liliaceae) indicates that a lack of DNA removal characterizes extreme expansions in genome size.

New Phytologist 208: 596-607.

Projects Plus

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Ilia J. Leitch

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Ilia J. Leitch


Ilia J. Leitch






+ 44 (0) 208 332 5329