scholarly journals The Mechanism of Pathogenicity of Sirex Noctilio on Pinus Radiata II. Effects of S. Noctilio Mucus

1969 ◽  
Vol 22 (5) ◽  
pp. 1153 ◽  
Author(s):  
MP Coutts
Keyword(s):  
Pinus Radiata ◽  
Mucus Secretion ◽  
Premature Senescence ◽  
Physiological Changes ◽  
Sirex Noctilio ◽  
Increased Susceptibility

Effects on P. radiata of a mucus secretion from the female wood wasp are described. When injected into the sapwood, this substance induced the rapid physiological changes in the crown which are characteristic of trees attacked by S. noctilio. Among these was the accumulation of starch in the leaf and a decrease of starch in the bark of the stem implying that the translocation of photosynthate was inhibited. This was followed by premature senescence and abscission of much of the foliage and increased susceptibility to the fungus, Amylostereum sp., which occurs in symbiosis with the insect. Therefore it is concluded that the mucus secretion conditions the tree, which is subsequently killed by the fungus.

Vegetation Changes as a Result of Invasion of Forest on Krasnozem by Phytophthora cinnamomi

1980 ◽  
Vol 28 (2) ◽  
pp. 139 ◽  
Author(s):  
G Weste
Keyword(s):  
Pinus Radiata ◽  
Phytophthora Cinnamomi ◽  
First Year ◽  
Acacia Dealbata ◽  
Sclerophyll Forest ◽  
Lower Height ◽  
Leaf Spot Fungus ◽  
Future Status ◽  
Reduced Water ◽  
Increased Susceptibility

Disease caused by Phytophthora cinnamomi was studied for 5 years in native and planted forest growing on krasnozem in the northern foothills of the Great Dividing Range at Narbethong, 100 km northwest of Melbourne. Changes in species composition were recorded for three sites carrying mature dry sclerophyll forest of Eucalyptus obliqua and Eucalyptus radiata, young plantations of E. obliqua, and young plantations of Pinus radiata. The mature ecualypts were diseased in 1974 and now are gradually dying. The young E. obliqua showed greater resistance than the older trees to the pathogen but infected trees were characterized by lower height, small leaves with reduced water potential, and an increased susceptibility to the leaf spot fungus Aulographina eucalypti. Susceptible understorey species such as Tetratheca ciliata and Epacris impressa died, but seedling regeneration of these has since occurred on one site. No species has disappeared from all three sites but T. ciliata and Daviesia latifolia almost disappeared from site 2, and the total number of plants was reduced. Species such as Leptospermum juniperinum and Platylobium formosum developed fluctuating cycles of chlorosis and die-back followed by either recovery or death. Resistant plants such as sedges, grasses and Acacia dealbata invaded the diseased forest. During the first year of the investigation 13% of the 4-year-old Pinus radiata died, but this particular site was well drained, warmer and drier than the others and the surviving pines later grew vigorously and crowded out other species. Symptoms are no longer evident on this site. The future status of the mature forest and the probable effects of disease on the young E. obliqua plantation are discussed.

Phase-change related epigenetic and physiological changes in Pinus radiata D. Don

Planta ◽  
2002 ◽  
Vol 215 (4) ◽  
pp. 672-678 ◽  
Author(s):  
Mario Fraga ◽  
Maria Ca�al ◽  
Roberto Rodr�guez
Keyword(s):  
Phase Change ◽  
Pinus Radiata ◽  
Physiological Changes

Physiological reactions of Pinus radiata to attack by woodwasp, Sirex noctilio F. (Hymenoptera: Siricidae)

1977 ◽  
Vol 67 (3) ◽  
pp. 405-426 ◽  
Author(s):  
J. L. Madden
Keyword(s):  
Pinus Radiata ◽  
High Water ◽  
Sirex Noctilio ◽  
General Hypothesis ◽  
Breeding Sites ◽  
Physiological Processes ◽  
Host Trees ◽  
Successful Establishment ◽  
In Trans ◽  
Individual Trees

AbstractPhysiological studies of Pinus radiata damaged artificially and of others attacked by Sirex noctilio F. indicated that temporary disturbances of the normal physiology of the host trees produce potential breeding sites for the woodwasp. Different physiological processes within trees were monitored after treatment and attack; these included changes in trans-location, transpiration, phloem respiration and osmotic and moisture content. The response of the S. noctilio to trees baited with phloem extracts or monoterpene solutions was investigated. The results of these studies, together with the published findings of other workers on the effects of insect secretions on trees and the resistance phenomenon, were interpreted into a general hypothesis of the interaction of the insect with the host tree. It was found that damage impaired translocation and enhanced transpiration and phloem respiration. These changes resulted in changes in tissue permeability and increased the rates of monoterpene and water vapour loss through the bark. The attraction of S. noctilio to trees was related to these changes, and the lowered osmotic status of the phloem favoured egg deposition. Drilling also was accompanied by the secretion of arthrospores of the symbiotic fungus Amylostereum areolatum and mucus, which inhibited translocation. High water tensions in stressed trees favoured fungus invasion, and low turgor resulting from the permeability changes minimised resinosis at oviposition sites. Successful establishment of the fungus, together with the effects of the mucus, resulted in tree death and the creation of a suitable milieu for Sirex development. The hypothesis proposes that the outcome of any attack is related to the duration and effects of the initial stressor on the tree and the tree's ability to moderate these effects. The response in the physiology of individual trees to stress affects the probability of attack while the resultant interaction between insect and tree determines the intensity of drilling, arthrospore and mucus load, and tree susceptibility or resistance to that attack.

scholarly journals Identity of the Fungal Symbiont of Sirex Noctilio

1969 ◽  
Vol 22 (4) ◽  
pp. 905 ◽  
Author(s):  
I PC Gaut
Keyword(s):  
Tissue Culture ◽  
Pinus Radiata ◽  
Gel Electrophoresis ◽  
Culture Medium ◽  
Callus Tissue ◽  
Starch Gel Electrophoresis ◽  
Polystyrene Film ◽  
Fungal Symbiont ◽  
Sirex Noctilio ◽  
Starch Gel

The fungus associated with S. noctilio F. in Australia is identified as Amyloster-eum areolatum (Fr.) Boidin. By using a polystyrene film to prevent the breakup of the chains of arthrospores during staining, it was possible to demonstrate that the spores are homokaryotic though usually multinucleate. Viable homokaryons were established from arthrospores by using a tissue culture medium incorporating growing callus tissue of Pinus radiata. Homokaryons and heterokaryons of the S. noctilio fungus were opposed in all possible combinations against homokaryons and heterokaryons of A. chailleti'i (Pers. ex Fr.) Boidin, A.laevigatum (Fr.) Boidin, and A. areolatum, the only known species of Amylostereum. The S. noctilio fungus was interfertile only with A. areolatum, as judged by production of anastomoses, clamped mycelium, and fertile fruit bodies. Starch-gel electrophoresis showed that the soluble proteins of the S. noctilio fungus corresponded more closely with those of A. areolatum than with those of A. chailletii.

An analysis of an outbreak of the woodwasp, Sirex noctilio F. (Hymenoptera, Siricidae), in Pinus radiata

1975 ◽  
Vol 65 (3) ◽  
pp. 491-500 ◽  
Author(s):  
J. L. Madden
Keyword(s):  
Pinus Radiata ◽  
Growth Ring ◽  
Summer Rainfall ◽  
Growth Patterns ◽  
Site Quality ◽  
Sirex Noctilio ◽  
Growth Rings ◽  
Plantation Management ◽  
Previous Season ◽  
Ring Analysis

AbstractThe development of an outbreak of the woodwasp, Sirex noctilio F., in a 30-year-old population of Pinus radiata in Tasmania was traced by growth ring analysis of killed trees. The outbreak probably developed from small foci; it reached its peak when the trees were 18–19 years old and then declined rapidly. Attack per tree was directly related to the density of emergents from trees killed in the previous season and the intensity of oviposition drilling was modified by the rainfall during the emergence season; the frequency of treble oviposition drills was directly related to summer rainfall. Survival of insects within trees declined with the years; this was related to the greater vigour and resistance of the surviving trees, but was apparently modified by spring rainfall. Resinosis and polyphenols associated with growth rings in stems living in 1964 indicated an increase in the proportion of trees resisting attack during the outbreak. The growth patterns of attacked and unattacked trees, and the obvious susceptibility of the weaker understorey trees, are discussed and due attention to site quality and plantation management are recommended to reduce Sirex attack in future.

Some treatments which render Monterey pine (Pinus radiata) attractive to the wood wasp Sirex noctilio F.

1971 ◽  
Vol 60 (3) ◽  
pp. 467-472 ◽  
Author(s):  
J. L. Madden
Keyword(s):  
Pinus Radiata ◽  
Temporal Patterns ◽  
Host Tree ◽  
Sirex Noctilio ◽  
Monterey Pine

Characteristic temporal patterns of attack by Sirex noctilio F. in Tasmania were obtained when Pinus radiata trees were either felled, completely lopped or high trimmed and girdled. Felling resulted in immediate attack whereas lopped and girdled trees were not attacked until some 9–12 days later. Felled trees were susceptible to attack for about 14 days, but lopped and girdled trees were attacked for longer periods. In some instances girdled trees remained susceptible for more than one season. Oviposition by caged S. noctilio females on healthy trees was followed by attack from wild females about 9 days later. It is shown that the timing and duration of attack by S. noctilio are correlated with the degree of stress undergone by the host tree.

scholarly journals Preliminary Studies on the Mucus Secretion of the Wood Wasp, Sirex Noctilio F. I. Physicochemical and Biochemical Properties

1976 ◽  
Vol 29 (2) ◽  
pp. 21 ◽  
Author(s):  
LK Wong ◽  
RK Crowden
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Enzyme Activities ◽  
Proteolytic Enzyme ◽  
Physiological Activity ◽  
Biochemical Properties ◽  
Mucus Secretion ◽  
Sirex Noctilio ◽  
Polysaccharide Complex

The major component of S. noctilio mucus appears to be a protein-polysaccharide complex with probable molecular weight in the range 60000-100000. In aqueous solution the macromolecule undergoes slow spontaneous disaggregation to yield dialysable subunits of molecular weight 2000-6000 which retain all the physiological activity of the whole mucus. More rapid disaggregation is brought about by treatment of solutions with moderate concentrations of NaC!, KCI or CaCI2 , or by heating. The native mucus contains amylase, esterase, phenoloxidase and proteolytic enzyme activities, and it is suggested that these enzymes may be responsible, at least in part, for the 'natural' disaggregation process.

scholarly journals Effect of Aging on Homeostasis in the Soft Tissue of the Periodontium: A Narrative Review

2021 ◽  
Vol 11 (1) ◽  
pp. 58
Author(s):  
Yu Gyung Kim ◽  
Sang Min Lee ◽  
Sungeun Bae ◽  
Taejun Park ◽  
Hyeonjin Kim ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Genomic Instability ◽  
Periodontal Ligament ◽  
Soft Tissues ◽  
Alveolar Bone ◽  
Current Knowledge ◽  
Complex Structure ◽  
Physiological Changes ◽  
Progressive Decline ◽  
Increased Susceptibility

Aging is characterized by a progressive decline or loss of physiological functions, leading to increased susceptibility to disease or death. Several aging hallmarks, including genomic instability, cellular senescence, and mitochondrial dysfunction, have been suggested, which often lead to the numerous aging disorders. The periodontium, a complex structure surrounding and supporting the teeth, is composed of the gingiva, periodontal ligament, cementum, and alveolar bone. Supportive and protective roles of the periodontium are very critical to sustain life, but the periodontium undergoes morphological and physiological changes with age. In this review, we summarize the current knowledge of molecular and cellular physiological changes in the periodontium, by focusing on soft tissues including gingiva and periodontal ligament.

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