Proceedings of the XLVII Italian Society of Agricultural Genetics - SIGA Annual Congress

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Poster Abstract - 1.51

FROM SEED GERMINATION TO FLOWERING, CRYPTOCHROMES AFFECT MULTIPLE ASPECTS OF TOMATO PLANT DEVELOPMENT

L. GILIBERTO*, M. TAVAZZA*, P. PALLARA**, F. GIORNO**, G. PERROTTA**, G. GIULIANO*

*) Ente per le Nuove Tecnologie, l'Energia e l'Ambiente (ENEA), Biotechnology Unit, Casaccia Research Centre, PO Box 2400, Roma 00100AD, Italy

**) Ente per le Nuove Tecnologie, l'Energia e l'Ambiente (ENEA), Biotechnology Unit, Trisaia Research Centre, 75026 Rotondella (MT), Italy

tomato, photoperiodism, de-etiolation

Cryptochromes are flavin-type blue light photoreceptors, widespread in plants and animals. We have started the functional characterisation of the tomato cryptochrome gene family. Tomato contains 2 Cry1 genes, 1 Cry2 gene and 1 putative CryDash gene. Homologous, ectopic expression of the Cry2 gene produces some phenotypes similar to what already observed in Arabidopsis and tobacco (hypocotyl and internode shortening, anthocyanin accumulation), while other phenotypes are novel: modification of leaf chlorophyll and carotenoid content, of seed germination, and of flowering time. Some of the phenotypes are reversible through posttranscriptional gene silencing with a viral vector carrying a fragment of the Cry2 gene. Experiments conducted under controlled conditions show that tomato, (cv. Moneymaker), like Arabidopsis, flowers earlier under long day conditions and requires light for seed germination. Ectopic expression of Cry2 affects seed germination, and retards flowering. Analysis of cry1 mutant plants confirms that tomato cryptochromes control tomato seed germination and flowering in a fashion radically different from Arabidopsis.

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