Anatomical Aspects of Root Bud Development in Hoop Pine (Araucaria cunninghamii)

1990 ◽  
Vol 38 (1) ◽  
pp. 73 ◽  
Author(s):  
GE Burrows
Keyword(s):  
Leaf Morphology ◽  
Lateral Roots ◽  
Bud Development ◽  
Primary Xylem ◽  
Juvenile Leaf ◽  
Hoop Pine ◽  
Araucaria Cunninghamii

Root bud development was studied in the severed, secondarily thickened, lateral roots of 20-year-old hoop pines (Araucaria cunninghamii Aiton ex D. Don). The buds arose adventitiously in the parenchyma of the proliferated pericycle at positions opposite the diarch primary xylem poles, although they were not associated with lateral roots. The buds had an orthotropic mainstem and juvenile leaf morphology and could thus be a useful source of material for vegetatively propagating elite hoop pines.

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.

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.

scholarly journals Structure of Panax quinquefolius L. (Araliaceae) Roots with Emphasis on Secretory Duct Formation

1998 ◽  
Vol 123 (5) ◽  
pp. 798-801 ◽  
Author(s):  
R. Larry Peterson ◽  
Gregory T. Varney ◽  
Shannon Binns
Keyword(s):  
Lateral Roots ◽  
Primary Root ◽  
Secondary Growth ◽  
Panax Quinquefolius ◽  
Secondary Phloem ◽  
Primary Xylem ◽  
Casparian Bands ◽  
Transmission Electron ◽  
Anatomical Localization ◽  
Secretory Ducts

Primary and first-order lateral roots of Panax quinquefolius L. (American ginseng) were collected from plants in an experimental garden during their second year of growth and processed for light and transmission electron microscopy. Roots in primary growth had either a diarch or triarch primary xylem pattern, a pericycle, an endodermis with Casparian bands and subsequently a suberized cell wall, and a cortex of variable thickness with a suberized hypodermal layer. Both root types underwent rapid secondary growth and the primary root particularly formed a fleshy storage organ. The secondary phloem and secondary xylem had abundant parenchyma and few conducting elements. Secretory ducts differentiated in tissue derived from the pericycle and in the secondary phloem. Each schizogenous duct consisted of six to eight epithelial cells, which possessed dense, globular deposits but lacked starch. A phellogen, which produced several layers of suberized phellem, was initiated in the periphery of tissue derived from the pericycle. The results of this study clarify the anatomical localization of secretory duets in roots of this species.

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. 

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