A Scanning and Transmission Electron Microscope Study of Leaf Axil Structure in Araucaria cunninghamii

1991 ◽  
Vol 39 (1) ◽  
pp. 67 ◽  
Author(s):  
GE Burrows
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Leaf Axil ◽  
Thin Walls ◽  
Hoop Pine ◽  
Axillary Meristems ◽  
Full Complement ◽  
Plasmodesmatal Frequency ◽  
Transmission Electron Microscope Study ◽  
Storage Products ◽  
Araucaria Cunninghamii

The cells of active plant meristems are characterised by their small size, thin walls and a full complement of organelles, most noticeably a large nucleus surrounded by densely staining, little-vacuolated cytoplasm. The axillary meristems of Araucaria cunninghamii Aiton ex D. Don (hoop pine) possess a similar ultrastructure, even though they quickly assume a near complete, potentially permanent quiescence following their detachment from the flanks of the actively dividing apical meristem. However, they differ from metabolically active cells in that those organelles and structures associated with cytokinesis and cell wall formation are either absent (microtubules) or infrequent and in an apparently inactive state (smooth endoplasmic reticulum, non-vesiculating dictyosomes, nuclei with a low heterochromatin to euchromatin ratio). In addition, storage products (starch, lipid globules), usually not present in metabolically active cells, are well developed. In addition to not developing a bud-like organisation, the meristems are also unlike typical axillary buds in that they have no vascular or provascular connections with the axial vascular tissues and are bounded adaxially by a group of thick-walled cells. While these cells constitute a physical barrier around the axillary meristems, they are nucleated and possess numerous simple pits that have a high plasmodesmatal frequency. Thus it appears that the meristems are not physiologically isolated, but are in cytoplasmic continuity with the remainder of the plant.

In vitro Propagation of Araucaria cunninghamii and Other Species of the Araucariaceae Via Axillary Meristems

1988 ◽  
Vol 36 (6) ◽  
pp. 665 ◽  
Author(s):  
GE Burrows ◽  
DD Doley ◽  
RJ Haines ◽  
DG Nikles
Keyword(s):  
Basal Medium ◽  
Ground Level ◽  
Total Inhibition ◽  
Hoop Pine ◽  
Axillary Meristems ◽  
Medium Level ◽  
Half Strength ◽  
Araucaria Cunninghamii ◽  
Stem Segments

Stem segments with 3-5 leaf axils, excised from the upper portion of the mainstem of 2-year-old hoop pine (Araucaria cunninghamii Aiton ex D. Don) seedlings, produced orthotropic buds from the concealed axillary meristems when cultured on a basal medium (BM) of half-strength Murashige and Skoog (MS) inorganic salts, the medium level of growth factors and amino acids of de Fossard, 20 g L sucrose and 6.5 g/L agar. This procedure was also successful with A. balansae, A. bidwillii, A. colurnnaris, A. hunsteinri, A. luxurians, A. montana, A. rulei, A. scopulorum and Agathis robusta and with stem segments from orthotropic coppice shoots of juvenile morphology collected from the stumps of 20-year old hoop pines felled near ground level. The hoop pine explants were highly sensitive to cytokinin; 1 μM and 10 μM 6-benzylaminopurine caused the formation of distorted buds and total inhibition of bud development respectively. Lofier concentrations (0.001-0.1 μM ) did not noticeably influence bud formation or development. A low rate of multiplication was induced by reculturing the stem segments after the excision of the initial shoots. New buds developed in the leaf axils of that part of the initial shoot which remained attached to the primary stem explant. Shoots derived from seedling and coppice cultures of hoop pine and seedling cultures of Agathis robusta rooted in vitro on BM + 0.1-10.0 μM indole-3-butyric acid (IBA), but with only 5-20% success. Up to 80% rooting was obtained if both hoop pine shoot types (i. e. from seedling and coppice cultures) were cultured on modified BM (quarter strength MS salts, 10 μM IBA plus no agar) for 2 weeks, before being transferred to a mixture of non-sterile peat and perlite or vermiculite and perlite, maintained under a high humidity (90-95%). Plantlets were subsequently transferred to normal glasshouse conditions and then to the field with less than 5% mortality. Thus hoop pine can be added to the relatively small number of conifers for which the capacity to micropropagate juvenile and mature plants and successfully establish their clones in the field has been demonstrated.

Infestation, susceptibility and damage of Araucaria plantations in papua new guinea by Hylurdrectonus araucariae Schedl (Coleoptera, Scolytidae)

1976 ◽  
Vol 66 (4) ◽  
pp. 695-711
Author(s):  
B. Gray
Keyword(s):  
Papua New Guinea ◽  
New Guinea ◽  
Growth Increment ◽  
Good Growth ◽  
Seedling Resistance ◽  
Pine Seedlings ◽  
Hoop Pine ◽  
Plantation Species ◽  
Araucaria Cunninghamii ◽  
Old Trees

AbstractA branchlet-mining scolytid beetle, Hylurdrectonus araucariae Schedl, has invaded the hoop pine (Araucaria cunninghamii) plantations at Bulolo and Wau in Papua New Guinea. A study of the infestation pattern in a plot of 184 young (5–6 year-old) trees at Bulolo from February 1968–August 1972 revealed four major phases: (i), a relatively prolonged but small build-up of the population on most trees over a period of 12–18 months following the first attack; (ii), a dramatic upsurge in the infestation over the following 12–18 months, reaching a peak infestation with the severe attack of nearly all trees in the plot; (iii), a sharp decline in the number of attacks and population over the next 12–18 months due to a lack of nest sites and food and (iv), a slow decline over a protracted period. The variation (313 to 6220) in the maximum number of infested branchlets on the trees in the plot at peak attack was great, due to the differing amounts of foliage and size of the trees, but it usually represented an estimated 85–95% of the foliage.A comparative study of seedling resistance of the two major plantation species, hoop pine and klinkii pine (Araucaria hunsteinii) was carried out at Bulolo in 1967 using seedlings from the local nursery and placing them in cages with large quantities of infested foliage. Over a two-month period, no colonies of H. araucariae were established in the klinkii pine seedlings and only three of 32 attacks recorded in the hoop pine seedlings had produced brood. Infestation of seedlings was extremely rare in the plantations and natural stands. On the other hand, most trees aged 2·5 to 12 years in the plantations at Bulolo and Wau were susceptible to severe infestation. Older trees were seldom severely attacked. Klinkii pine has proved non-susceptible to attack. In studies of impact in three plots of 1000 trees at Bulolo from 1967–1971, least growth increment and highest mortality was recorded in the plot that had been initially severely affected by the scolytid. In contrast, good growth and low mortality was recorded in the plot of healthy trees. They were later exposed to severe infestation from the adjacent plantation of young 3–4 year-old trees, but escaped relatively unscathed. In another study of impact at Bulolo from 1967–1972, the effect of two levels of pruning on subsequent growth and re-infestation was examined. The results indicated that site also strongly affected the situation, with little growth and high mortality evident on poor sites. Secondary insects, notably the weevil Vanapa oberthueri Pouillaude, were an important factor contributing to mortality among the stressed trees.

Distinguishing the Woods of Araucaria Cunninghamii (Hoop Pine) and Araucaria Bidwilli (Bunya Pine)

IAWA Journal ◽  
1995 ◽  
Vol 16 (3) ◽  
pp. 255-260 ◽  
Author(s):  
J. Ilie
Keyword(s):  
Southern Hemisphere ◽  
The Past ◽  
Hoop Pine ◽  
Araucaria Cunninghamii

Araucaria today is endemic to the Southern Hemisphere, with three species in Australia. Araucaria cunninghamii Ait. ex D.Don (Hoop Pine) and A. bidwilli Hook. (Bunya Pine) were cut in the past and marketed together as Colonial Pine. Today only A. cunninghamii is cut commercially, mainly from plantations established in the last few decades.

Eurhamphus pancinii, a new species of the genus Eurhamphus Shuckard, 1838 (Coleoptera: Curculionidae: Molytinae: Orthorhinini) from West Papua

Zootaxa ◽  
2019 ◽  
Vol 4613 (3) ◽  
pp. 596
Author(s):  
ROBERT S. ANDERSON
Keyword(s):  
New Species ◽  
New South ◽  
New South Wales ◽  
Plant Associations ◽  
South Wales ◽  
Hoop Pine ◽  
West Papua ◽  
Araucaria Cunninghamii ◽  
A New Species

Eurhamphus pancinii n. sp. is described based on a series of specimens collected in West Papua, in the Arfak Mountains and on Yapen Island. The only other species in the genus is Eurhamphus fasciculatus Shuckard known from New South Wales northwards into Queensland in Australia. The new species is distinguished from E. fasciculatus by the pronotum and elytra with the glabrous raised areas between the rows of scales very narrow, and elytra with sutural and interstria 3 low and evenly rounded throughout length, elytra in profile not humped towards base (both sexes), and in males by a shorter, less strongly dorsally granulate rostrum, front and middle tibia with inner margins with a very small subapical tooth, and inner edge of front tibia with only a few short, subapical hairs. Eurhamphus fasciculatus is associated with Hoop Pine, Araucaria cunninghamii and although no plant associations are available for specimens of the new species it is expected to be similarly associated with Araucaria. 

Characterization of Hoop Pine (Araucaria Cunninghamii Sweet) for Ply and Particleboard Manufacture

2014 ◽  
Vol 37 (2) ◽  
pp. 143-146
Author(s):  
Md. Rahaman ◽  
Khurshid Akhter ◽  
M.W. Sheikh ◽  
R. Akhter
Keyword(s):  
Bending Strength ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Solid Content ◽  
British Standard ◽  
Press Temperature ◽  
Hoop Pine ◽  
Araucaria Cunninghamii ◽  
Press Time

Studies for assessing the suitability of Hoop-pine (Araucaria cunninghamii) wood for plywood and particleboard manufacture. It was found that 1.5 mm thick smooth and figured veneer can be made and dried easily. Three-ply plywood were made using veneer of this species bonded with liquid urea formaldehyde glue of 50% solid content, extended with wheat flour and catalyzed (ammonium chloride) with 2% hardener under the specific pressures, viz, 1.05 N/mm2, 1.40 N/mm2, 1.76 N/mm2 in three replications at 6 minutes press time and 120°C press temperature. Dry and wet shear test were conducted on the sample and their shear load at failure per unit area and percentage of wood failure were determined. 1.40 N/mm2 pressure was found best for the manufacture of plywood. The physical and mechanical properties of hoop-pine particleboard were studied. The particleboards were tested for determining the strength and dimensional stability. The tensile strength passed the German and British standard specifications, bending strength found to nearest the Indian Standard but did not pass the German and British standard specifications.

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