et al., 2013 ), thereby chemical pinching has been used to enhance lateral branching. Application of PGRs is generally less labor intensive than hand pinching; however, PGRs may cause phytotoxicity ( Meijón et al., 2009 ). Plant growth regulators with
Amir Rezazadeh, Richard L. Harkess, and Guihong Bi
Renata Koyama, Adriane Marinho de Assis, Lilian Yukari Yamamoto, Wellington Fernando Borges, Rogério de Sá Borges, Sandra Helena Prudêncio, and Sergio Ruffo Roberto
). Since then, the effects of S -ABA have been tested basically on V. vinifera table grapes ( Peppi et al., 2007 ; Peppi and Fidelibus, 2008 ; Roberto et al., 2012 , 2013 ), but the effect of this plant growth regulator on V. labrusca grapes with
I-Ling Lai, Chih-Wan Lin, Tsai-Yu Chen, and Wei-Hsin Hu
vitro propagation of the F1 hybridized progeny of B. montaniformis × B. ningmingensis var. bella (Novel F1), especially in terms of plant growth regulators (PGRs) and light quality. Materials and Methods Plant materials. Individual plants of B
Diego A. Mata and Javier F. Botto
warm temperatures and high irradiances promote accelerated plant growth. Under these circumstances, the control of plant height is an issue of big concern to produce plants with high commercial quality. Many growers use plant growth regulators (PGRs) to
Diana R. Cochran, Amy Fulcher, and Guihong Bi
) for 20 min per application using 3.2 gal/h PCNL spray stakes. Plant growth regulator application. On 23 May 2012, ‘Limelight’ plants were divided into two branching treatment groups: pruned or unpruned. Pruned plants were hand-pruned (cuts were made on
Anna Perkins Nina Bassuk
Budbreak inhibition and poor overwinter survival (OS) limit successful cutting propagation of Acer rubrum October Glory, A. rubrum Red Sunset, Hamamelis vernalis, H. virginiana and Stewartia pseudocamellia. Localized blanching (banding) of the cutting on the stock plant; a range of 3 IBA concentrations, and foliar spray application of: 1% silver thiosulfate(STS), STS followed ten days later by Gibberellin, GA4/7:250ppm(STS GA),50ppm thidiazuron (TDZ) and TDZ followed by GA4/7 (TDZ GA)were tested for increasing growth and overwinter survival.. Carbohydrates were analyzed in cuttings which did and didn't grow. A. rubrum October Glory*, and Hamamelis spp all had increased OS for cuttings which grew. A. rubrum Red Sunset demonstrated a similar trend. Hamamelis spp. had significant increase in carbohydrates for cuttings which grew. A. rubrum October Glory' exhibited the same trend. S. pseudocamellia did not have increased OS with growth. and showed no increases in carbohydrates with growth, but the cuttings that didn't grow had at least 93 % more carbohydrates than the other species analyzed. All species had higher OS when stored in the 3° C cooler, than in the fluctuating cold frame. Banding increased growth of A. rubrum October Glory, and H. virginiana. IBA concentration affected growth of all species. STS increased growth of H. virginiana and S. pseudocamellia. GA4/7 increased growth of all cuttings except A. rubrum October Glory.
Jeff S. Kuehny, Wen Chy Chang, and Patricia Branch
Zantesdeschia has been grown for cut-flower production for many years, but more recently it has been grown as a containerized plant. Problems with height control and disease, however, have limited Zantesdeschia production in warmer climates. Our objectives were to evaluate paclobutrazol and uniconazole on control of plant growth of three Zantesdeschia species and evaluate four preplant treatments for preventing Erwinia infection on rhizomes. Paclobutrazol at 1 mg a.i. gave the best control of flower height, foliage height, and plant width. After 20 d in a postharvest chamber, plants drenched with paclobuturazol at 2 mg a.i. and uniconazole at 6 mg a.i. were still suitable plants, plants drenched at 3 and 4 mg a.i. paclobutrazol remained short, and plants drenched at 2 and 4 mg a.i.uniconazole became tall and weak, with flower stems breaking over. Rhizomes were dipped in dimethylbenzyl ammonium chlorides, sodium hypochlorite, 4% formaldehyde, or streptomycin. Streptomycin provided the best control against Erwinia infection followed by formaldehyde. Dimethylbenzyl ammonium chlorides and sodium chloride provided the poorest protection.
Xiaoling Cao and F.A. Hammerschlag
As part of a program to develop transgenic highbush blueberry (Vaccinium corymbosum L.) cultivars, studies were conducted to determine optimum conditions for high efficiency shoot regeneration from leaf explants of in vitro-propagated shoot cultures. The effect of either thidiazuron at 1 or 5 μM, or zeatin riboside at 20 μM, and two lit levels (18 ± 5 or 55 ± 5 μmol·m-2·s-1) on shoot organogenesis were investigated. With the exception of `Bluecrop', which did not regenerate shoots, maximum shoot regeneration of 13, 12.7, 12.6 and 4.6 shoots per explant for cultivars Duke, Georgiagem, Sierra, and Jersey, respectively, occured on regeneration medium with zeatin riboside and under a light intensity of 55 μmol·m-2·s-1. Whereas `Duke' regenerated equally well on regeneration medium with either zeatin riboside or 5 μM thidiazuron, regeneration frequencies for `Georgiagem' and `Sierra' were significantly higher on zeatin riboside. A light intensity of 55 μmol·m-2·s-1 significantly increased regeneration of cultivars Duke, Jersey, and Sierra on zeatin riboside, but inhibited regeneration of Duke on 5 μM thidazuron.
Rajendra P. Maurya* and Champa lal Nagda*
In a field experiment, uniform sized corms of gladiolus (Gladiolus grandiflorus L. cv. Oscar) were planted in last week of October at a distance of 30 cm. between rows and 20 cm. between plants. The effect of GA (50, 100 ppm), Cycocel (500, 1000) and NAA (50, 100 ppm) on gladiolus plants. It was concluded that foliar application of 100 ppm GA3 at 45 days after corm planting has shown superiority in all vegetative, floral characters and corm & cormel yield viz., plant height (128.53 cm), number of leaves (8.57) per plant, spike length (108.33 cm), spike weight (128.87 g), number of florets (17.60) per spike, size of second florets (15.07 cm), number of spikes (1.67) per plant, size of largest corm (7.52 cm), number of corms (1.80) per plant, number of cormels (11.53) per plant and weight of corms (79.33 g) per plant. Whereas, a highest longevity of florets opening or survival on spike (20.33 days) was recorded in 1000 ppm Cycocel.
Wenhao Dai and Cielo Castillo
cells ( Herman and Hess, 1963 ). Shortening the photoperiod, decreasing light intensity, and dark treatment will result in thinner cell walls and lower cell wall deposits, facilitating penetration of plant growth regulators into cells ( Herman and Hess