Search Results

You are looking at 41 - 50 of 69 items for

  • Author or Editor: Brent K. Harbaugh x
Clear All Modify Search


Eight lacewing (Chrysopa earned) larvae per greenhouse snapdragon (Antirrhinum majus), released 4 at a time twice during 8 weeks effectively controlled aphids (Myzus persicae). Two initial sprays of malathion and nicotine sulfate 1 week apart followed by release of 4 lacewing larvae per plant also were effective. Flowers produced under chemical or biological control systems were equal in quality. Lacewing larvae in a 21°C greenhouse required a week longer to effectively control aphids than those in a 24°C greenhouse.

Open Access

Seedlings of commercial lisianthus cultivars form rosettes when grown at 25 to 28°C. Rosetted plants have a basal cluster of leaves, very short internodes typical of biennials, and do not bolt or flower for months without being exposed to 3 to 4 weeks at <15 to 18°C to reverse heat-induced rosetting. Semirosetted plants develop when seedlings are grown at a constant 22 to 25°C or at <22°C night with >28°C day. Semirosetted plants have one or more side shoots which may elongate and flower, but plants flower unpredictably and are of poor quality as cut flowers or potted plants. `Maurine Blue' and Florida Blue' were released from the Univ. of Florida in 1995. To our knowledge, they are the first heat-tolerant lisianthus cultivars. Seedlings and plants can be grown at 28 to 31°C without rosetting. `Maurine Blue' ranged in height from 38 cm (summer) to 67 cm (spring) during 1994 and 1995 production trials in Florida. `Maurine Blue' has potential for use as a tall bedding plant if sold as green transplants, a flowering potted plant if grown with three plants per 15-cm-diameter pot with a growth retardant, or as a bouquet-type cut flower. `Florida Blue' plants (38 cm) grown in an 11.5-cm square pot (0.65-L) with capillary mat irrigation were similar in height to `Blue Lisa' (32 cm) and taller than `Little Belle Blue' (22 cm) and `Mermaid Blue' (24 cm). `Florida Blue' was designated as a semi-dwarf cultivar with an intended use as a bedding plant. Growth retardants would be useful for production in pots <10 to 12 cm in diameter. Complete descriptive information, photographs and pedigrees will be presented.

Free access

Lisianthus [Eustoma grandiflorum (Raf). Shinn.] is emerging as an important cut flower in the United States while in European and Asian markets it is already listed among the top ten cut flowers. Many new cultivars have been released in the United States within the last 5 years, but comparative performance trials of these cultivars have been lacking. This trial evaluated 47 cultivars of lisianthus representing series (cultivar groups) that were marketed in the United States in 1998. Evaluations were made for rosetting, plug performance, cut-flower characteristics (vegetative and flowering attributes) as well as postharvest longevity of cut flowers. Significant differences among cultivars were found for all of the attributes evaluated. `Malibu Purple', `Catalina Blue Blush', and `Alice Pink' were selected as the best performers in the seedling (plug) stage since they had less than 5% rosettes, large leaves and a vigorous root system. Cultivars were placed in classes based on flower color, flower size, and number of petals (single or double flowers). Cultivars were ranked for each of the attributes and the total rank sum of all attributes (TRS) was used to select the best in class. Cultivars selected as best in class were `Malibu Purple', `Malibu Blue Blush', `Alice Purple', `Balboa Blue', `Avila Blue Rim', `Mellow Pink', `Flamenco Wine Red', `Flamenco Rose Rim', `Alice Pink', `Avila Rose' and `Echo Pink', `Alice White', and `Mariachi White'.

Full access