Genetic, molecular and breeding study of coleus (Solenostemon scutellarioides (L.) Codd) during growth and development.

摘要

Solenostemon scutellarioides (syn. Coleus blumei Benth.), commonly known as coleus, is a member of the Lamiaceae family and is highly prized for its vibrant and colorful foliage. In the last decade, coleus has gained popularity in the floriculture industry with the introduction of a large number of vegetatively propagated varieties with novel foliage colors. Besides novel foliage colors, opportunities exist to increase their commercial value by manipulating plant architecture. A breeding program was initiated at the University of Florida with focus on two main objectives: (1) the development of new trailing types with bright foliage colors, and (2) the development of new varieties with improved vigor, foliage color quality and delayed flowering induction for production companies and consumers. At the completion of the breeding program, in regards to new trailing types, several with bright orange colors were successfully produced and are currently being trialed in the greenhouse. Over a three year period, twenty-one new varieties were released from the breeding program with improved vigor, foliage color quality, and delayed flowering induction. During the development of new varieties with improved color quality, many varieties in the program were observed to become dark red when exposed to high light intensities. As a lack of information existed to explain color change in coleus, a focus on a third objective was pursued. A study was conducted on two related coleus varieties, 'Royal Glissade' and 'UF06-1-6', to determine the physiological and molecular mechanisms involved in this color change phenomenon. Light intensity was found to affect coloration by inducing the accumulation of anthocyanin pigments in the leaves. Expression of the structural genes PAL, CHS, F3H, DFR, ANS, and UFGT and regulatory genes AN1 and AN2 were analyzed. DFR and UFGT were found to play an important role in foliage coloration in coleus.