New guinea impatiens (Impatiens hawkeri) (NGI) `Pure Beauty Rose' (PBR) and `Paradise Orchid' (PO) were grown in full sun, 55% shade, or 73% shade and fertilized with a controlled-release fertilizer (CRF) [Nutricote Total 13-13-13 (13N-5.7P-10.8K), type 100] incorporated at rates of 2, 4, 6, 8, 12, 16, 20, 24, 28 and 32 lb/yard3 of growing media (1.2, 2.4, 3.6, 4.7, 7.1, 9.5, 11.9, 14.2, 16.6, and 19.0 kg·m-3). Plant quality rating, shoot dry weight, and flower number were measured at harvest and substrate samples were collected to analyze final substrate pH and electrical conductivity (EC). For both cultivars, light intensity and fertilization rate interactions were different for shoot dry weight and flower number, but there was no difference in plant quality rating between the light levels. Quality ratings of both PBR and PO plants increased as CRF rate increased to 12 to 16 lb/yard3 above these levels quality was not improved. Shoot dry weight of PBR plants grown in full sun increased as CRF rate increased to 28 lb/yard3 and then decreased, while shoot dry weight of plants grown with 55% and 73% shade increased as CRF rate increased to 20 and 16 lb/yard3, respectively, with no further increases. Shoot dry weight of PO plants grown in full sun and 55% shade increased as CRF rate increased to 28 and 24 lb/yard3, respectively, with no further increases, while shoot dry weight of plants grown with 73% shade increased as CRF rate increased to 24 lb/yard3 and then decreased. Flower number of PBR plants grown in full sun, 55% shade, and 73% shade increased as CRF rate increased to 24 lb/yard3 and then decreased. Flower number of PO plants grown in full sun increased as CRF rate increased to 28 lb/yard3 and then decreased, while flower number of plants grown in 55% and 73% shade increased as CRF rate increased to 24 lb/yard3 and then decreased.
Wagner Vendrame, Kimberly K. Moore, and Timothy K. Broschat
T.J. Gianfagna, R.H. Merritt, and J.D. Willmott
Aquilegia cultivars `Songbird Bluebird', `Songbird Robin', `Dove Improved', `Colorado Violet/White' and five cultivars from new experimental genetic lines (`Red and White', `Rose and White #1', `Rose and White #2', `Scarlet and Yellow' and `White') will flower without vernalization, but little is known of their response to light or plant growth regulators. Plants were started from seed on 5 Jan. 1999 and grown in either natural light or 33% shade, and treated with gibberellins (GA4/7) at the seven-leaf stage. Flowering time, number of flowers/plant, and plant height were evaluated through 31 May 1999. All five cultivars from the new genetic lines bloomed during the study. `White', grown in shade and treated with GA4/7, bloomed 2 weeks earlier (115 days) than untreated plants grown in natural light (130 days). `Songbird Robin', treated with GA4/7, bloomed in 146 days, and was the only other cultivar to bloom. Flower numbers were greater in natural light than in 33% shade. GA4/7 increased flowering for four of five cultivars, in the new genetic lines, grown in natural light. In shade, GA4/7 increased flowering for three of five cultivars. Height response to GA4/7 was significant in both natural light and 33% shade. Four of the five cultivars in the new genetic lines were taller when treated. All five of these cultivars were taller when grown in natural light verses 33% shade. `White' and both `Rose and White' cultivars were consistently taller, bloomed earlier and were more floriferous when treated with GA4/7.
Emily G. Tenczar and Vera A. Krischik
resistant to specialist leaf-feeding beetles (Coleoptera) and moths (Lepidoptera). Coevolutionary theory argues that new phytochemicals in a plant may permit the plant to escape from herbivory by confusing the insect with the novel chemical. Specialist