Watermelon (Citrullus Lanatus (Thunb.) Matsum and Nakai) and muskmelon (Cucumis melo) were regenerated from immature cotyledons cultured on MS medium containing 10 μM BA. Small population of watermelon and muskmelon regenerants contained tetraploids as variants. The tetraploid individuals were recognized by morphological features including enlarged leaves, tendrils, male flowers, and variable pollen grains. After self-pollination, seed lots reflected differences in size expected from tetraploid parents.. Cytological data from root tips of R1 populations will be presented.
Jeffrey Adelberg, B.B. Rhodes, and Halina Skorupska
Robert Price, Marihelen Kamp-Glass, and David Powell
Venus fly trap, Dionaea muscipula Ellis, leaf sections were surfaced sterilized under aseptic conditions. The leaf sections were cultured in reduced strength Muashige and Skoog growth medium supplemented with 2,25 mg/l 6-Benzylaminopurine and 1.0-2.0 mg/l Kinetin. The various levels of cytokinin were used to differentiate and enhance callus formation.
Jameel M. Al-Khayri, Feng H. Huang, Teddy E. Morelock, and Tahani A. Busharar
A preliminary study has shown that the addition of 15% (v/v) coconut water (CW) to the culture medium significantly improved callus growth, shoot-regenerative capacity, and shoot growth in leaf disk cultures of spinach (Spinacia oleracea L.). Subsequently, the influence of a range of CW concentrations, 0%, 5%, 10%, 15%, or 20% (v/v), was examined. Callus weight obtained after 5 weeks showed direct relationship to the concentration of CW. This stimulator action was observed in both cultivars tested in this study, `High Pack' and `Baker'. On CW-containing medium, shoot regeneration was expedited to 4 to 5 weeks compared with 8 to 12 weeks on a CW-free medium. Callus of `Baker' induced on a CW-free medium exhibited a significant increase in shoot regeneration frequency when transferred to a regeneration medium enriched with CW, suggesting that the addition of CW to the regeneration medium only is sufficient to achieve improved regeneration.
Brent Tisserat, Danny Jones, and Paul D. Galletta
Nutrient medium can be sterilized using a household-type microwave oven. The required microwave treatment time was influenced by the oven's microwave power intensity (70 to 700 W), vessel type, volume of medium employed, and the presence of energy sink water reservoirs (ESWR). Growth rates of strawberry (Fragaria vesca L.) shootlets, lemon [Citrus limon (L.) Burm. f.] fruit halves, or carrot (Daucus carota L.) callus cultured on either microwaved or autoclaved media were similar. Microwaving and autoclaving appeared to reduce GA3 activity compared with medium containing filter sterilized GA3. Chemical name used: gibberellic acid (GA3).
Carrie A. Radcliffe, James M. Affolter, and Hazel Y. Wetzstein
for reintroduction and safeguarding purposes. Ex situ propagation efforts often play an integral role in plant conservation ( Guerrant et al., 2004 ; Maunder and Culham, 1999 ). Tissue culture has been used to propagate rare species ( Fay, 1992 ; Fay
J. Ben-Jaacov, A. Ackerman, E. Tal, and G. Jacobs
Wojciech J. Florkowski, Orville M. Lindstrom, Carol D. Robacker, and H.R. Simonton
Claudine M. Bona, Jean H. Gould, J. Creighton Miller, David M. Stelly Jr., and Eliezer S. Louzada
The highly appreciated Euvitis subgenera species (2n=38) are very susceptible to pests and diseases. Tolerance/resistance may be found in the closely related Vitis rotundifolia cultivars (2n=40), but the poor rooting characteristic of this species is a problem, and conventional crossings between Euvitis and V. rotundifolia are complicated because of different chromosome numbers. Therefore, somatic hybridization may be an alternative for gene transference between these species. The establishment of an efficient in vitro procedure may facilitate future genetic manipulations. Furthermore, in vitro success may be an indicative of protoplast totipotency. The goal of this research was to test 11 cultivars from different species for their in vitro cultivation and protoplast isolation capacity. Different doses of benzyladenine (BA) were tested and explants were cultivated in both Lloyd and McCown's Woody Plant Medium (WPM) and Murashige and Skoog medium (MS). We established an efficient in vitro procedure and plants of C. sauvignon, Syrah, SV 12-375, Scuppernong, Magnolia, Higgens and B. beauty were regenerated. No rooting problem was observed in vitro. Black spanish and Herbemont callus were kept in vitro, but plants were not regenerated. SV-12327 and Jumbo died. WPM was more efficient than MS for most cultivars. The V. vinifera cultivars C. sauvignon and Syrah developed well in both media. Protoplast isolation was more efficient using leaves rather than callus or suspension cells. BA at 3 μM·L-1 induced organogenesis while 10 μM·L-1 induced callogenesis except for Syrah, where 1 μM·L-1 induced organogenesis. Protoplasts were isolated from Herbemont and C. sauvignon and microcallus were obtained.
S. Abou Taleb, I. Yates, B.W. Wood, and M.M. Fouad
A study was conducted to develop protocol for the preservation of pecan genetic variability by cryogenic storage of zygotic embryos and subsequent in vitro plant regeneration. Parameters evaluated for their influence on embryo survival included the amount of intact kernel, liquid nitrogen (LN) treatment, desiccation, and genotype specificity. Optimum germination with minimum contamination occurred with 12% of the kernel intact. Treatment of explants with LN reduced the percentage of embryos developing into intact plants. `Curtis' and `Shoshoni' had a significantly higher morphogenic response in shoots only than all other cultivars. In summary, cryogenic storage of pecan zygotic embryos was determined to be a feasible means for preservation of pecan germplasm. However, the procedures used in the current study should be altered to increase the probability of embryo survival.
James E. Faust, Jeffrey W. Adelberg, Kelly P. Lewis, and Genhua Niu
The effects of storage temperature and shoot preparation of elephant ears (Colocasia antiquorum `Illustris') were examined to determine how to successfully store plants prior to greenhouse forcing. A series of experiments were conducted that provided storage temperatures of 4, 7, 10, 13, or 16 °C (39.2, 44.6, 50.0, 55.4, or 60.8 °F), and plants were placed into storage with the shoots uncut or cut to 3.0 cm (1.18 inches) above the surface of the growing medium. The storage duration ranged from 40 to 49 days. All plants stored at 4 or 7 °C died. Plant survival was 89% to 100% at 10 °C, while plant survival was 100% at 13 or 16 °C. Shoot emergence and plant growth was faster following storage at 13 and 16 °C, than storage at 10 °C. Storage at 16 °C resulted in leaf growth occurring during storage, which was undesirable. Removing shoots prior to storage had no effect on plant survival and performance during forcing. A fungicide drench with iprodione immediately prior to storage did not improve plant survival. This study suggests that 13 °C is near the base temperature for leaf development of elephant ears, thus the plants survive at this temperature with no growth occurring. Shoot removal prior to storage is recommended in order to optimize storage room space.