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Terri Woods Starman

This study investigated the effects of concentration and application time of uniconazole as a spray for single- or double-pinched ornamental pepper (Capsicum annuum L. `Holiday Cheer'). Concentrations from 5.0 to 15.0 mg·liter-1 gave adequate height control, except that 15.0 mg·liter-1 reduced height excessively when applied 8, but not 10, weeks after sowing. Increasing uniconazole concentration increased red fruit percentage when applied at 10, but not 8, weeks after sowing. These results indicate that the later application was beneficial and may lessen the overdosing problem associated with triazole growth regulators. Chemical name used: (E)-(S)-1-(4-chlrophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-oll(uniconazole).

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Terri Woods Starman

Manually and chemically pinched plants of 18 cultivars of Impatiens hybrids (Kientzler New Guinea impatiens) were compared to control plants to determine the effect of shoot apex removal on flowering, plant size, and branching characteristics. Either pinching treatment delayed flowering by ≈3 days compared with nonpinched controls. Pinching had no effect on plant height or fresh or dry weight. Plant diameter and form changes due to pinching depended on cultivar. Total branch count was increased by chemical but not manual pinching although both pinching methods affected mode of branching. The 18 cultivars of Kientzler New Guinea impatiens were best grown as 0.4-liter potted plants without the aid of pinching.

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Terri Starman and Leonardo Lombardini

A study was conducted to characterize the morphological and physiological responses of four herbaceous perennial species subjected to two subsequent drought cycles. Lantana camara L. `New Gold' (lantana), Lobelia cardinalis L. (cardinal flower), Salvia farinacea Benth. `Henry Duelberg' (mealy sage), and Scaevola aemula R. Br. `New Wonder' (fan flower) were subjected to two consecutive 10-day drought cycles. Growth response, leaf gas exchange, and chlorophyll fluorescence were measured during the experiment. The morphology of L. cardinalis and L. camara was not affected by drought, while S. farinacea had reductions in plant height and leaf area and S. aemula had reductions in dry weight. Overall, plant growth and development continued even when substrate water content was reduced to 0.13 mm3·mm-3, which indicated a level of substrate water below container capacity was sufficient for greenhouse production of these species. The drought treatments had little effect on the photochemical efficiency (Fv/Fm) of Photosystem II. An increase in minimal fluorescence (Fo) was observed in S. aemula on the last day of the second cycle. Drought treatment caused increased leaf-level water use efficiency (WUE) at the end of the first cycle in L. cardinalis and S. aemula, but not in L. camara and S. farinacea. Plants of L. camara, S. farinacea, and S. aemula that had received drought during both cycles became more water use efficient by the end of the second cycle, but L. cardinalis did not.

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Terri Woods Starman

Single and multiple sprays of uniconazole at 0, 5, 10, or 20 mg·liter-1 were compared with daminozide sprays at 2500 mg·liter-1 applied twice for height control of Dendranthema × grandiflorum (Ramat.) Kitamura (Chrysanthemum × morifolium Ramat.) `Puritan' and `Favor'. A single uniconazole spray at 20 mg·liter-1 applied 2 weeks after pinching or two uniconazole applications at 10 mg·liter-1 applied 2 and 4 weeks after pinching were as effective as daminozide for reducing height. Drenches of uniconazole at 0, 0.025, 0.05, or 0.10 mg a.i./pot were compared with ancymidol drenches at 0.45 mg a.i./pot for controlling height of `Bright Golden Anne'. Although ancymidol was more effective, a 0.10-mg uniconazole drench adequately reduced height.

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Terri Woods Starman

One and two foliar spray and single-drench applications of uniconazole were applied to Eustoma grandiflorum (Raf.) Shinn (lisianthus) `Yodel Blue' to determine optimal concentrations for potted plant height control. A single uniconazole spray at 10.0 mg·liter-1 applied 2 weeks after pinching, two uniconazole applications at 5.0 mg·liter -1 applied 2 and 3 weeks after pinching, or a drench at 1.60 mg a.i. per pot applied 2 weeks after pinching gave equally good height control. At these concentrations, uniconazole was similar in its effect on plant height to daminozide foliar sprays at 7500 and 2500 mg·liter-l applied once and twice, respectively. Drenching with uniconazole at 1.60 mg a.i. per pot did not increase days to flower (DTF), whereas foliar spray applications did. Drenching did not reduce flower size, but increased flower number at time of harvest. Chemical names used: α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono(2,2-dimethylhydrazide) (daminozide);(E)-(S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-01 (uniconazole).

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Terri Woods Starman

Manually pinched plants of 18 cultivars of Impatiens hybrids (Keintzler New Guinea impatiens) were compared to control plants to determine the effect of apical meristem removal on flowering, growth and branching. Pinching delayed days to anthesis (first flower) of all cultivars, however, further delay in days to marketability (5 flowers open) was dependent upon cultivar. Plant area and fresh and dry weight were not affected by pinching plants of any cultivar. Cultivar influenced response to pinching treatments for plant height and plant width. Secondary branch number was increased by approximately 3 branches for all cultivars when plants were pinched. There were interactions between cultivar and treatment for primary, tertiary, and total branch number. Measured improvements in plant form determined two cultivars, Sylvine and Thecla, should be pinched. Chemically pinching these two cultivars with dikegulac at 780 mg·liter-1 was comparable to manually pinching plants.

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Terri Woods Starman and Shane Abbitt

The objective was to distinguish between series of cultivars of Pelargonium xhortorum (zonal geranium), Pelargonium hybrids (seed geranium), and Pelargonium peltatum (ivy leaf geranium) using DNA amplification fingerprinting (DAF) demonstrating the utility of DAF for patent protection to prevent infringement of inventor's rights. Leaf tissue of 10 plants of each cultivar of seedling geranium was bulked for DNA extraction, and cutting and ivy geranium cultivars were bulks of five plants of each cultivar. Isolated DNA from different cultivars of a series were bulked together in their respective series. Seedling geranium series included Dynamo, Glamour, Multibloom, Orbit, Pinto, and Ringo 2000. Cutting geranium series included Designer and Showcase. Ivy geraniums were from the Guillou group. Amplification was with one of two octamer primers, followed by reamplifying with one of four different mini hairpin primers. Gels were visually scored for presence or absence of bands. The four primers generated 336 bands. The average number of bands (_1000 bp) per primer was 40. Twenty percent of bands were polymorphic and distinguished between each series of cultivars. Genetic relationships were evaluated by SAHN cluster analysis based on the distance estimator of Dice using the NTSYS-pc program (Numerical taxonomy and multivariate analysis system, version 1.8). Series were grouped according to species. Seedling geraniums were in one large group, the two cutting geraniums were grouped together and the ivy leaf geraniums were a separate branch.

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Terri Woods Starman and Shane Abbitt

Our objective was to distinguish between eight cultivars of two geranium species, Pelargonium ×hortorum L.H. Bailey (cutting and seed geranium) and Pelargonium peltatum (L.) L'Hér. ex Ait. (ivy geranium), and evaluate their genetic relationships using the nucleic acid scanning techniques of DNA amplification fingerprinting (DAF) and/or arbitrary signatures from amplification profiles (ASAP). Cultivars used in the study represented three commercial types: cutting, seed, and ivy geranium. Two seed geranium cultivars from each of the Dynamo and Orbit series were included. Cutting geranium cultivars were `Designer Lilac Chiffon' and `Starburst Red' and the ivy geraniums were `Bernardo Guiber' and `Vinco Guivin'. The ASAP amplification protocol used one of two arbitrary octamer primers, followed by reamplification with one of four different minihairpin primers. ASAP profiles were complex, with 66% of bands being polymorphic and useful in distinguishing between cultivars. Genetic relationships were evaluated by principal coordinate analysis and cluster analysis based on the Jaccard distance estimator. This analysis grouped cultivars by species according to commercial type, i.e., seed geraniums were in one large group, the cutting geraniums were grouped together, and the ivy geraniums were a separate branch.

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Terri Woods Starman and Shane Abbitt

The objective was to distinguish between cultivars and evaluate genetic relatedness of poinsettia (Euphorbia pulcherrima) using two methods of DNA fingerprinting—DNA Amplification Fingerprinting (DAF) and Arbitrary Signatures from Amplification Profiles (ASAP). Eleven red poinsettia cultivars were studied, including `Celebrate 2', `Darlyne', `Freedom Red', `Lilo', `Nutcracker Red', `Peterstar Red', `Petoy', `Red Sails', `Supjibi', `V-14 Glory', and `V-17 Angelika'. Amplification was with 10 octamer primers. Gels were visually scored for presence or absence of bands. The 10 primers generated 336 bands. The average number of bands (≈1000 bp) per primer was 34 ranging from 19 to 43. Thirty-one percent of bands were polymorphic and distinguished between each cultivar. The number of unique profiles varied from two to nine. Genetic relationships were evaluated by SAHN cluster analysis based on the distance estimator of Jaccard using the NTSYS-pc program (Numerical taxonomy and multivariate analysis system, version 1.8). The resulting dendrogram closely agreed with known pedigree data. ASAP analysis was used to further assess cultivar identification of two cultivars that were genetically and morphologically similar. Markers were found that separated `Nutcracker Red' and `Peterstar Red'. ASAP analysis separated cultivars within the Freedom series that DAF failed to distinguish. Two cultivars in the Freedom series, `Jingle Bells' and `Marble', were characterized from other cultivars in the series with ASAP.