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1.
N. Hammatt 《World journal of microbiology & biotechnology》1992,8(4):369-377
An increasing world population and rise in demand for tree products, especially wood, has increased the need to produce more timber through planting more forest with improved quality stock. Superior trees are likely to arise from several sources. Firstly, forest trees can be selected from wild populations and cloned using macropropagation techniques already being investigated for fruit tree rootstocks. Alternatively, propagation might be brought aboutin vitro through micropropagation or sustained somatic embryogenesis, with encapsulation of the somatic embryos to form artificial seeds. Tree quality could be improved through increased plant breeding and it is likely that experienced gained, to date, in the breeding of fruit species will be useful in devising strategies for forest trees. Since the development of techniques to regenerate woody plants from explant tissues, cells and protoplasts, it is now feasible to test the use of tissue culture methods to bring about improvements in tree quality. Success has already been achieved for tree species in the generation of somaclonal and protoclonal variation, the formation of haploids, triploids and polyploids, somatic hybrids and cybrids and the introduction of foreign DNA through transformation. This review summarizes the advances made so far in tree biotechnology, and suggests some of the directions that it might take in the future. 相似文献
2.
Promotion by phloroglucinol of adventitious root formation in micropropagated shoots of adult wild cherry (Prunus avium L.) 总被引:1,自引:0,他引:1
Neil Hammatt 《Plant Growth Regulation》1994,14(2):127-132
Micropropagated shoots of wild cherry (Prunus avium L.) produced roots in auxin-free medium. Phloroglucinol (PG) increased the proportion of shoots that rooted, while phloretic acid reduced this response in medium with or without PG, and cancelled the promotive effect of PG. Concentration of PG also significantly affected rooting in media with and without auxin. The proportion of shoots rooting in media containing auxin, or auxin plus PG, increased with the number of successive subculture, but the proportion that rooted with PG alone was unaffected by the number of subcultures. Before the shoots had become responsive to auxin, 1 mM PG was more effective than auxin in inducing root formation. 相似文献
3.
4.
S. K. Jaiswal N. Hammatt S. S. Bhojwani E. C. Cocking M. R. Davey 《Plant Cell, Tissue and Organ Culture》1990,22(3):159-165
Protoplasts isolated from cotyledons of Brassica carinata, underwent sustained division when cultured at 5.0 × 104 ml-1 in modified 8p medium (KM8P) with 1.0% (w/v) Seaplaque agarose. Cell colonies produced callus when agarose droplets, in which the protoplasts were embedded, were transferred to K8 medium with 0.6% (w/v) Sigma Type I or Type VII agarose at day 16, giving a plating efficiency of 1.6%. Seventy percent of the protoplast derived-tissues produced shoot buds after subculture to MS medium containing 3.0% (w/v) sucrose, 1.125 mgl-1 BAP, 0.035 mgl-1 GA and 0.6% (w/v) Type I agarose, resulting in shoot formation from 1.1% of the protoplasts originally plated. Protoplast-derived colonies transferred to hormone-free MS medium with 1.0% (w/v) sucrose and 0.6% (w/v) Type I agarose produced roots. The latter gave rise to shoots after excision from the parent callus and culture on MS medium with 3.0% sucrose, 0.225 mgl-1 BAP, and 0.6% (w/v) Type I agarose. Shoots regenerated directly from protoplast-derived calli, or indirectly from roots, developed prolific root systems when placed on hormone-free MS medium with 1.0% (w/v) sucrose and 0.6% (w/v) Type I agarose.Abbreviations BAP
6-benzylaminopurine
- CH
casein hydrolysate
- 2,4-D
2,4-dichlorophenoxyacetic acid
- GA
gibberellic acid
- K
kinetin
- NAA
-naphthaleneacetic acid
- MES
2(N-morpholino)ethanesulphonic acid, 2,iP-6(,-dimethylallyamino) purine
- IAA
indole-3-acetic acid
- Z
zeatin
- ZR
zeatin riboside 相似文献
5.
Shoot regeneration from leaves of Prunus serotina Ehrh. (black cherry) and P. avium L. (wild cherry) 总被引:3,自引:0,他引:3
Leaves excised from shoot cultures of Prunus avium cvs. F12/1 and Charger and genotype 1908, and from five genotypes of P. serotina and two hybrids of P. avium×P. sargentii developed shoots on Woody Plant medium (WPM) supplemented with either benzyladenine (BA) or thidiazuron (TDZ). Regeneration
in both P. avium 1908 and a genotype of P. serotina was improved using TDZ rather than BA in the medium. Regeneration occurred more frequently in P. serotina if leaves were cultured on medium with WPM rather than modified Driver and Kuniyuki walnut medium. The proportions of leaves
that regenerated varied between genotypes of the same species. Regenerated shoots of both P. avium and P. serotina developed into shoot cultures following transfer to the media used to produce the shoot cultures used as explant sources.
Received: 10 July 1996 / Revision received: 11 November 1996 / Accepted: 6 January 1997 相似文献
6.
Asian elephants (Elephas maximus) in western zoos are likely to become extinct unless elephants are regrouped into breeding units or additional elephants are imported from range States. There have been proposals for the export of elephants from elephant camps in Sumatra, Indonesia. In exchange, zoos would be expected to provide funds or support ‘in kind’ for the camps or for the conservation of wild elephants. Most of the elephants in the Sumatran camps were captured because of crop‐raiding problems around protected areas or because elephant habitat has been and continues to be lost to development schemes and illegal conversion of protected areas to agriculture. Capture‐related mortality rates are high and conditions in the camps are poor, with low standards of veterinary care and husbandry. This is partly due to over‐crowding and inadequate budgets. It might seem, therefore, that the loan of elephants to western zoos would improve the lot of these elephants and reduce the pressures on the camps. However, we show that both total and annual demand for Asian elephants, and particularly Sumatran elephants (E. m. sumatranus), by western zoos are low, and consequently the resources generated by any loan scheme would be limited. Elephant loan schemes are unlikely to have significant beneficial impact on either the conservation or welfare of elephants in Sumatra. More importantly, a credible loan scheme would require a permanent moratorium on the capture of wild elephants in Sumatra. Such a moratorium is needed to prevent illicit captures for sale or loan. At present, wild elephants are caught to replace those that die at the camps or are moved to other facilities. Without a moratorium, the loan of elephants to overseas zoos would contribute directly to reductions in wild elephant populations in Sumatra. However, a moratorium is likely to prove impossible to enforce, and this alone should call into question the desirability of any loan scheme. Zoo Biol 25:235–246, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
7.
N. Hammatt 《Plant cell reports》1999,18(6):478-484
The development of micropropagated wild cherry (Prunus avium L.) was compared in the nursery and the field with cuttings and seedlings, over a total period of 6 years. Summer semi-hardwood
cuttings tended to produce moderate numbers of branches in the season following propagation, whereas micropropagules and seedlings
produced significantly fewer or none at all. Removal of branches from cuttings resulted in taller trees. A greater proportion
of cuttings than micropropagules flowered in the first year in which trees produced flowers. In the second flowering year,
there were no differences in flowering habit between cuttings and micropropagules. Propagation by cuttings or micropropagation
did not consistently affect increments in stem diameters or heights. These results are discussed in terms of the suitability
of micropropagation and cuttings to produce clonal wild cherry.
Received: 23 February 1997 / Revision received: 3 January 1998 / Accepted: 5 February 1998 相似文献
8.
N. Hammatt B. Jones M. R. Davey 《In vitro cellular & developmental biology. Plant》1989,25(7):669-672
Summary Plants have been regenerated from nodular, green callus derived from cotyledon, petiole and leaf lamina explants ofG. argyrea, a perennial relative of the soybean (G. max). The degree of response obtained was governed primarily by the genotype used, accession G1626 proving the most responsive.
Shoots were also recovered from about 6.0% of cotyledon protoplasts of this genotype. The implications of these results are
discussed in relation to genetic manipulations using this species. 相似文献
9.
E. L. Rech T. J. Golds T. Husnain M. H. Vainstein B. Jones N. Hammatt B. J. Mulligan M. R. Davey 《Plant cell reports》1989,8(1):33-36
Seedling hypocotyl explants ofGlycine canescens were inoculated withAgrobacterium rhizogenes carrying a chimaeric NPTII gene cointegrated into the TL-DNA of pRiA4. Transformed roots produced shoots on B5 based medium with 10.0 mgl–1 BAP, 0.05 mgl–1 IBA and 50 gml–1 kanamycin. Cultured roots and regenerated plants expressed NPTII enzyme activity which was correlated with the presence of Ri TL-DNA and the structural sequence of the NPTII gene.Abbreviations BAP
6-benzylaminopurine
- BSA
bovine serum albumin
- DTT
dithiothreitol
- EDTA
ethylenediaminetetraacetic acid
- IBA
indole-butyric acid
- PAGE
polyacrylamide gel electrophoresis
- NPTII
neomycin phosphotransferase II
- PMSF
phenylmethylsulphonyl fluoride
- SDS
sodium dodecylsulphate 相似文献
10.
Summary Protoplasts were isolated seedling hypocotyls of soybean (Glycine max), and cultured in both liquid and agarose-solidified, modified K8P medium. Nuclear staining revealed that only 2% of protoplasts
lacked a nucleus, 93% contained a single nucleus, and 5% contained more than one. Maximum protoplast yields and subsequent
division frequencies, in liquid medium, were obtained from 5 days-old seedlings. Maximum division frequencies (54%) were obtained
from hypocotyl protoplasts plated at a density of 5×104 ml−1. Using different osmolality reduction régimes for liquid cultures, hypocotyl protoplasts developed into green, nodular callus,
similar to that which has previously given rise to shoot buds in perennialGlycine species. This tissue, however, did not produce shoot buds in soybean.
N. H. was supported by a SERC CASE studentship and a postdoctoral fellowship from Shell Research Ltd., Sittingbourne, Kent,
UK. 相似文献