Toxicity of antibiotics on zygotic embryos of white spruce (Picea glauca) cultured in vitro

1989 ◽  
Vol 8 (4) ◽  
pp. 214-216 ◽  
Author(s):  
E. W. T. Tsang ◽  
H. David ◽  
A. David ◽  
D. I. Dunstan
1990 ◽  
Vol 68 (12) ◽  
pp. 2583-2589 ◽  
Author(s):  
S. M. Attree ◽  
T. E. Tautorus ◽  
D. I. Dunstan ◽  
L. C. Fowke

Somatic embryo maturation, germination, and soil establishment frequencies were compared for two conifer species, white and black spruce (Picea glauca and Picea mariana). The comparison of the two species regenerated and established in soil under the same conditions showed black spruce to be the most responsive. Shorter exposure times to 32 μM abscisic acid were not as effective as maturation on a medium containing 16 μM abscisic acid for 28 days. This gave similar maturation frequencies for the two species (6–8%), and germination frequencies of 64% for white spruce and over 73% for black spruce. Over 1800 black and white spruce plantlets were recovered, and more than 400 were transferred from in vitro to nonsterile conditions. Sixty percent (160) of the black spruce plantlets survived transfer and continued to grow vigorously. By comparison only 18% (29) of the white spruce plantlets survived, and half of these rapidly produced dormant buds and underwent no further shoot growth. White spruce plants that did not produce dormant buds grew vigorously. These results indicate that there are large differences in the ability of these closely related species to respond to plantlet establishment following regeneration from somatic embryos, and that black spruce is highly responsive to micropropagation by this method. Key words: Picea glauca, Picea mariana, somatic embryogenesis, maturation, germination, soil establishment.


1988 ◽  
Vol 7 (5) ◽  
pp. 318-321 ◽  
Author(s):  
P. M. A. Toivonen ◽  
K. K. Kartha
Keyword(s):  

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3535 ◽  
Author(s):  
Melissa H. Mageroy ◽  
Denis Lachance ◽  
Sharon Jancsik ◽  
Geneviève Parent ◽  
Armand Séguin ◽  
...  

Eastern spruce budworm (Choristoneura fumiferiana Clemens) (ESBW) is a major forest pest which feeds on young shoots of white spruce (Picea glauca) and can cause landscape level economic and ecological losses. Release of acetophenone metabolites, piceol and pungenol, from their corresponding glycosides, picein and pungenin, can confer natural resistance of spruce to ESBW. A beta-glucosidase gene, Pgβglu-1, was recently discovered and the encoded enzyme was characterized in vitro to function in the release of the defensive acetophenone aglycons. Here we describe overexpression of Pgβglu-1 in a white spruce genotype whose metabolome contains the glucosylated acetophenones, but no detectable amounts of the aglycons. Transgenic overexpression of Pgβglu-1 resulted in release of the acetophenone aglycons in planta. This work provides in vivo evidence for the function of Pgβglu-1.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ying Cui ◽  
Jian Zhao ◽  
Ying Gao ◽  
Ruirui Zhao ◽  
Jinfeng Zhang ◽  
...  

Conifers are the world's major source of timber and pulpwood and have great economic and ecological value. Currently, little research on the application of CRISPR/Cas9, the commonly used genome-editing tool in angiosperms, has been reported in coniferous species. An efficient CRISPR/Cas9 system based on somatic embryogenesis (SEis) suitable for conifers could benefit both fundamental and applied research in these species. In this study, the SpCas9 gene was optimized based on codon bias in white spruce, and a spruce U6 promoter was cloned and function-validated for use in a conifer specific CRISPR/Cas9 toolbox, i.e., PgCas9/PaU6. With this toolbox, a genome-editing vector was constructed to target the DXS1 gene of white spruce. By Agrobacterium-mediated transformation, the genome-editing vector was then transferred into embryogenic tissue of white spruce. Three resistant embryogenic tissues were obtained and used for regenerating plants via SEis. Albino somatic embryo (SE) plants with mutations in DXS1 were obtained in all of the three events, and the ratios of the homozygous and biallelic mutants in the 18 albino mutants detected were 22.2% in both cases. Green plants with mutations in DXS1 were also produced, and the ratios of the DXS1 mutants to the total green plants were 7.9, 28, and 13.5%, respectively, among the three events. Since 22.7% of the total 44 mutants were edited at both of the target sites 1 and 2, the CRISPR/Cas9 toolbox in this research could be used for multi-sites genome editing. More than 2,000 SE plants were regenerated in vitro after genome editing, and part of them showed differences in plant development. Both chimerism and mosaicism were found in the SE plants of white spruce after genome editing with the CRISPR/Cas9 toolbox. The conifer-specific CRISPR/Cas9 system developed in this research could be valuable in gene function research and trait improvement.


1998 ◽  
Vol 76 (5) ◽  
pp. 751-761 ◽  
Author(s):  
Edward C Yeung ◽  
Claudio Stasolla ◽  
Lisheng Kong

The first notable sign of shoot and root meristem development in zygotic embryos of white spruce (Picea glauca (Moench) Voss) was the appearance of starch in the respective poles of the embryo. Starch granules gradually accumulated in the subapical cells of the shoot pole and were soon followed by vacuolation in the subapical cells. Vacuolation reached its highest degree in these cells at the early embryo stage. With the formation of the large vacuolated cells, the surface cell layer at the summit of the shoot pole enlarged and differentiated into the surface initials of the shoot meristem. These cells were large with distinct nuclei. As the embryo matured, the large vacuoles within the subapical cells were replaced by small ones with a concomitant increase in the cytoplasmic density of the subapical cells. After germination, the surface initials remained distinct; however, the subapical cells had different fates depending on their location. The subapical cells located next to the surface initials became the central mother cells of the shoot meristem and those located near the cotyledon junction divided periclinally and gave rise to the epicotyl rib meristem. The remaining subapical cells near the procambium became part of the pith. In the root pole, starch could be found in the cap region terminating underneath the developing procambium at the club-shaped stage of embryo development. Two layers of root initials appeared at the junction between the developing procambium and the root cap. The initials were distinct as they were larger in size than surrounding cells. Cell division activity could not be detected in the layer of initials immediately next to the procambium, while mitotic activity could be seen in the adjoining layer next to the root cap. As the embryo matured, cells surrounding the root initials also took on structural characteristics similar to the root meristem initials. As a result, the region of the root meristem initials expanded in size, and the bilayered configuration became obscure. After germination, mitotic figures could be found in the root initials. As seedling continued to grow, fewer mitotic figures could be found in the root meristem cells adjacent to the procambium pole. In roots of mature plants, a group of isodiametric cells could be discerned between the procambium and the root cap. Mitotic activity was not readily detected within this group of isodiametric cells but mitotic figures could be found in surrounding cells.Key words: apical meristems, Picea glauca, white spruce, zygotic embryogenesis.


1989 ◽  
Vol 67 (6) ◽  
pp. 1790-1795 ◽  
Author(s):  
S. M. Attree ◽  
D. I. Dunstan ◽  
L. C. Fowke

Rapid and high frequency somatic embryo regeneration from protoplasts isolated from 10 embryogenic cell lines of white spruce (Picea glauca) is reported. Embryogenic callus was initiated from immature zygotic embryos as source material for protoplast isolation. Individual cell lines exhibited different capabilities for sustained growth. Protoplast plating efficiencies depended on the concentrations of macroelements included in the medium. Using a medium with reduced salts, individual protoplasts developed directly into embryos with no disorganized growth period. Protoplasts from newly established suspension cultures regenerated to recognizable somatic embryos within 8 days of culture. This embryo development was faster than that from protoplasts isolated from longer term suspension cultures. However, the latter suspensions yielded more protoplasts, displayed higher plating efficiencies, and differed in their response to media.


1991 ◽  
Vol 69 (9) ◽  
pp. 1873-1899 ◽  
Author(s):  
T. E. Tautorus ◽  
L. C. Fowke ◽  
D. I. Dunstan

Substantial progress has been made towards the development of systems for in vitro embryogenesis in conifers. Since the first report of somatic embryogenesis from zygotic embryos of Picea abies in 1985, cultured explants of at least 18 different coniferous species have been induced to produce somatic embryos. Somatic embryos have been cryopreserved, grown in liquid suspensions, and matured into plants. In addition, plantlets have been regenerated from protoplasts isolated from embryogenic suspensions of Picea glauca and Larix ×eurolepis, permitting studies into direct gene transfer and somatic hybridization. Currently however, it is only possible to obtain somatic embryogenesis from embryonic and juvenile explants. Furthermore, for most species the efficiency of plantlet production from somatic embryos is poor and remains a problem for the commercial utilization of this technology. Biochemical, cytological, and physiological studies of conifer somatic embryogenesis have resulted in improved knowledge concerning the origin of somatic embryos, storage product accumulation during embryo development, and similarities with zygotic embryos. Furthermore, the technique of indirect immunofluorescence microscopy has permitted investigations of the cytoskeleton in conifer cells and protoplasts, providing insights into cell division and morphogenesis. In this review, emphasis is placed on the more fundamental aspects of conifer somatic embryogenesis. Where possible, comparisons between zygotic and somatic embryogenesis are made. Key words: somatic embryogenesis, zygotic embryogenesis, conifers, review.


1990 ◽  
Vol 68 (2) ◽  
pp. 236-242 ◽  
Author(s):  
F. M. Tremblay

White spruce (Picea glauca) embryogenic callus was obtained using 3- to 11-year-old seeds as a source of zygotic embryos. They were cultured on half-strength Litvay's medium supplemented with 10 μM 2,4-dichlorophenoxyacetic acid, 5 μM benzylaminopurine, 1 g/L casein hydrolysate, 500 mg/L glutamine, and 1% sucrose. The frequency of induction of embryogenic callus was significantly improved by incubation at 25 °C and by a 4-h imbibition of the seeds. The yield of embryogenic callus was significantly affected by the geographic provenance of the seeds and by their number of years in storage. A significant correlation was also found between the yield of embryogénie callus and the percentage of germination of the seedlot used. Even after 11 years of storage, 40% of the zygotic embryos could produce an embryogenic callus when dissected from seeds with a high germination rate. Somatic embryos were matured after transfer onto an embryo development medium composed of the same medium but including 6% sucrose, 1 μM 2,4-dichlorophenoxyacetic acid, and 5 μM kinetin. The somatic embryos developed further under in vitro conditions and were then transplanted into soil. The somatic embryoderived plantlets established in the greenhouse were similar to control plantlets obtained from germinated seeds. Mature embryos from stored seeds were shown to constitute a valuable source for white spruce somatic embryogenesis.


Sign in / Sign up

Export Citation Format

Share Document