HORTSCIENCE VOL. 39(6) OCTOBER 2004 1220 Inheritance of Flower Color in Anagallis monelli L. Rosanna Freyre 1 Plant Biology, University of New Hampshire, G36 Spaulding Hall, Durham, NH 03824 Robert J. Griesbach Floral and Nursery Plant Research, U.S. National Arboretum, U.S. Dept. of Agriculture, Agricultural Research Service, BARC-West, Building 010A, Beltsville, MD 20705 Additional index words. Primulaceae, anthocyanins, flavonoids Abstract. Plants of Anagallis monelli in their native habitat or in cultivation have either blue or orange flowers. Clonally propagated cultivars, seed obtained from commercial sources and the resulting plants were grown in a greenhouse at the University of New Hampshire. F 2 progeny obtained from hybridization between blue- and orange-flowered plants had blue, orange or red flowers. There were no significant differences in petal pH of orange-, blue-, and red-flowered plants that could explain the differences in flower color. Anthocyanidins were characterized by high-performance liquid chromatography. Results indicated that blue color was due to malvidin, orange to pelargonidin, and red to delphinidin. Based on our segregation data, we propose a three-gene model to explain flower color inheritance in this species. The genus Anagallis is in the family Primulaceae, although recent phylogenetic studies based on DNA sequence data from three chloroplast genes and morphology have placed it in the family Myrsinaceae (Källersjö et al., 2000). There are about 28 species in the genus Anagallis, mostly native to Europe, Asia, Africa and America (Clapham et al., 1987). Anagallis monelli L. (taxonomic synonyms A. collina Schousboe, A. linifolia L.) is a short- lived perennial with blue flowers found in dry, open habitats in southwestern Europe (Tutin et al., 1972). Wild forms are diploid (2n = 20) (Talavera et al., 1997) and self-incompatible (Gibbs and Talavera, 2001; Talavera et al., 2001). A variant, diploid form of A. monelli with orange flowers is found in southern Italy and northern Africa (Freyre, unpublished data; Talavera, personal communication). Cultivated forms of A. monelli (blue pimper- nel) are vigorous with large, deep blue flowers and are used as annual bedding plants and for hanging baskets. ‘Gentian Blue’ is a seed- propagated blue cultivar sold by Thompson & Morgan (Jackson, N.J.). Presently, this and several other commercial seed companies carry only unnamed cultivars of blue pimpernel. Several vegetatively propagated cultivars are offered in the trade including blue-flowered ‘Skylover Blue’ and ‘Wildcat Blue’ and or- ange-flowered ‘Sunrise’ and ‘Wildcat Orange’. ‘Wildcat Blue’ and ‘Wildcat Orange’ (plant patents 10/721,990 and 10/721,991, respec- tively) were released from the ornamental breeding program at the University of New hampshire (UNH) in 2002. Harborne (1968) found the flavonols quer- cetin and kaempferol in flowers of A. arvensis and A. linifolia, and cited research finding 3- and 3,5-glycosides of malvidin, delphinidin and pelargonidin in different color forms in A. arvensis. Ishikura (1981) identified malvidin 3-rhamnoside, luteolin, luteolin 7-glucoside and quercetin 3-rhamnoside in blue-flowered A. arvensis. Elsherif (2000) isolated chalcone syn- thase and flavanone 3-hydroxylase from flowers of A. monelli ‘Skylover Blue’and ‘Sunrise’, and reported finding only pelargonidin derivatives in flowers of ‘Sunrise’ and only malvidin deriva- tives in flowers of ‘Skylover Blue’. We obtained A. monelli plants with a novel red flower color from hybridization between blue- and orange-flowered plants. The objectives of this study were to determine the biochemi- cal basis of blue, orange and red flower colors and propose a genetic model for inheritance of flower color in A. monelli hybrids. Materials and Methods Plant material. Plants of A. monelli ‘Sun- rise’ and seeds of ‘Gentian Blue’ were obtained from commercial sources and grown at UNH. All plants were maintained in 25-cm baskets using 560 Scotts coir soiless medium (The Scotts Co., Marysville, Ohio) during cooler months or 360 Scotts coir medium in the summer, in a greenhouse with 21 o C day/18 o C night set points. Fertilization was constant with a 20N–4.3P–16.7K fertilizer at a maximum of 150 mg·L –1 N. To ensure healthy growth, the growing medium pH was maintained between 5.7 to 6.3 and electroconductivity between 1.0 and 2.0 mS·cm –1 . Hybridization. In winter and spring months, photoperiod was increased to 16 h using night-interruption lighting (with high pressure sodium lamps) from 2200 to 0200 hr to induce flowering. Hybridizations were performed on emasculated, unopened buds and pedicels were tagged for identification. Approximately three weeks were allowed for fruit formation, and then watering was stopped to dry the plants and fruit. Fruit were harvested when brown and brittle on the outside, the placenta dry, and seeds a dark brown or black color. F 1 and F 2 seeds were sown in seed trays containing 360 Scotts coir, covered lightly with media and placed on a bench with intermittent mist. Trays were removed from the mist upon emer- gence of the first seedlings. Initially they were transplanted into small cell packs and later into 15- or 25-cm pots. Color and pH determination. Flower Fig. 1. Flowers of blue-, orange-, and red-flowered Anagallis monelli. HORTSCIENCE 39(6):1220–1223. 2004. Received for publication 29 Aug. 2003. Accepted for publication 23 Dec. 2003. Scientific contribu- tion 2198 from the New Hampshire Agricultural Experiment Station. We thank Thomas M. Davis for valuable discussions; Amy Douglas and Deborah Schneider for assistance in greenhouse research; and Kenneth Schroeder, Dennis Werner, and John Ham- mond for critically reviewing the manuscript. 1 To whom reprint requests should be addressed; e-mail rf@unh.edu.