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Witchhazel (Hamamelis sp.) cultivars are now available in an array of forms and flower colors, including several native, pollinator-friendly cultivars. However, little is known about response of witchhazel cultivars to powdery mildew (Podosphaera biuncinata) or the growth and flowering characteristics of witchhazel cultivars in a nursery field production setting. To provide growth, flowering, and disease incidence data to nursery growers, a cultivar trial including 23 cultivars of witchhazel representing five species was planted Apr. 2016 in McMinnville, TN. Plant growth, flowering density, length of bloom, and foliar disease incidence were evaluated over three growing seasons between May 2016 and Oct. 2018. ‘Zuccariniana’ japanese witchhazel (H. japonica) and ‘Sunglow’ common witchhazel (H. virginiana) showed the greatest height increase during the trial, and ‘Sunglow’ also added the most width during the trial. Cultivars with negative height or width growth included Sweet Sunshine chinese witchhazel (H. mollis) and hybrid witchhazels (H. ×intermedia) Aphrodite, Twilight, and Barmstedt Gold. Ten of the 23 cultivars experienced winter injury in the form of stem necrosis. Root crown sprouts were observed for all cultivars at least once during the trial. ‘Wisely Supreme’ chinese witchhazel had the longest bloom period, followed by ‘Westerstede’ and ‘Twilight’ hybrid witchhazels, whereas ‘Quasimodo’ vernal witchhazel (H. vernalis) had the greatest density of flowers. The hybrid witchhazel cultivars Aphrodite, Nina, and Arnold Promise and the common witchhazel cultivars Green Thumb and Sunglow were resistant to powdery mildew under trial conditions in all 3 years. ‘Twilight’ and ‘Barmstedt Gold’ hybrid witchhazel, ‘Little Suzie’ common witchhazel, ‘Wisley Supreme’ chinese witchhazel, and ‘Shibamichi Red’ japanese witchhazel were moderately resistant to powdery mildew.
Abstract
Of 260 plant introductions (PI) of okra [Abelmoschus esculentus (L.) Moench.] evaluated for disease resistance, 39 were resistant to southern root knot nematode [Meloidogyne incognita (Kofoid & White) (Chitwood)], 9 were resistant to fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum (A & K) Snyder and Hansen, and 3 were resistant to both. An introduction of A. manihot L., a wild relative of okra, was highly resistant to fusarium wilt.
All-American daylily cultivars named from 1994-2004 were evaluated for landscape performance and daylily rust (Puccinia hemerocallidis) susceptibility during 2003 and 2004. Cultivars included `Black-Eyed Stella', `Bitsy', `Leebea Orange Crush', `Plum Perfect', `Judith', `Starstruck', `Frankly Scarlet', `Lullaby Baby', `Lady Lucille', and `Chorus Line'. Bareroot plants were planted in raised beds composed of an Olivier silt loam soil in full sun and received irrigation as needed to prevent stress. Visual quality ratings were made weekly from 19 Apr. to 25 Oct. 2003 and 15 Mar. to 20 Sept. 2004. Included in the visual quality ratings were growth habit and flowering with favorable growth habit being compactness, foliage color, uniformity, and overall aesthetics, and favorable flowering being longevity and visual appeal. Flower observations were made in regard to time in bud and peak blooming periods over the same time frames. Daylily rust ratings were taken in September and November 2003 and in August and November 2004. Flowering observations indicated that Black Eyed Stella and Bitsy were the only cultivars showing reliable repeat bloom potential. Among the other cultivars, Judith was the earliest to bud and bloom but also had a blooming period of only 2 to 3 weeks compared to 4 to 5 weeks of bloom for other cultivars. Rust was most prevalent on Judith, Leebea Orange Crush, Starstruck and Lady Lucille. Judith and Leebea Orange Crush have rust symptoms earlier than other cultivars. `Plum Perfect', `Frankly Scarlet', `Bitsy', `Black Eyed Stella', and `Lullaby Baby' were least susceptible to daylily rust.
Performance evaluations of numerous annual and perennial herbaceous ornamentals were conducted in landscape settings in 2004 at the LSU AgCenter in Baton Rouge. A mid-summer through fall evaluation of Kong coleus found no difference in flowering performance and visual quality ratings of the five available cultivars. In a sun/shade study, Kong coleus cultivars in 60% shade were about 50% shorter than those in sun. Other impressive coleus have been Aurora Black Cherry and Mississippi Summer Sun. The Stained Glassworks series of coleus have been average performers. The Son series of lantanas (Sonrise, Sonset, Samson, Sonshine) have been top performers in terms of visual quality and continual bloom. All-America daylilies most prevalent to rust symptoms have included Judith, Leebea Orange Crush, Starstruck, Lady Lucille, and Chorus Line. Some rust has also been noted on Plum Perfect and Frankly Scarlet. Profusion Apricot and Profusion White have been less susceptible to Xanthomonas bacterial petal blight than Profusion Fire, Profusion Cherry, and Profusion Orange. Earth Kind roses, being promoted by Texas A&M, are being evaluated for landscape performance along with black spot and powdery mildew susceptibility. Most problematic cultivars thus far have included Georgetown Tea, Clotilde Soupert, Nacogdoches, Reve d'Or, New Dawn, Souvenir de St. Anne's, Spice, Lamarque, Puerto Rico, Sarah Jones, Ducher, and Louis Philippe. Lady Bird cosmos have been good late summer/early fall landscape performers.