Interaction between Diplodia pinea or Diplodia scrobiculata and fungal endophytes isolated from pine shoots

2012 ◽  
Vol 42 (10) ◽  
pp. 1819-1826 ◽  
Author(s):  
Oscar Santamaría ◽  
Denise R. Smith ◽  
Glen R. Stanosz

Four endophytes isolated from healthy shoots of adult red pine ( Pinus resinosa Aiton) or jack pine ( Pinus banksiana Lamb.) trees were tested as potential biocontrol agents of the conifer shoot blight and canker pathogens Diplodia pinea (Desmaz.) J. Kickx fil. and Diplodia scrobiculata J. de Wet, B. Slippers & M.J. Wingfield. The effect of the endophytes on the germination of Diplodia species conidia and on the symptom severity caused by these pathogens on P. banksiana seedlings under greenhouse conditions was evaluated. Aggressiveness of each organism also was determined by means of single inoculations on jack pine seedlings. The results indicated that the endophyte Trichoderma atroviride P. Karst. showed a clear antagonism to Diplodia species. The culture filtrate of this fungus was able to reduce spore germination of D. scrobiculata. Furthermore, it was able to inhibit the D. pinea invasion when both organisms were inoculated in the same seedling. The observed reduction in the symptom severity on jack pine seedlings might be due to parasitism and (or) production of inhibitory compounds. Therefore, T. atroviride might deserve further investigations for its use as biocontrol agent against D. pinea.

Plant Disease ◽  
2009 ◽  
Vol 93 (1) ◽  
pp. 81-86 ◽  
Author(s):  
Isabel A. Munck ◽  
Glen R. Stanosz

Frequency of detection and inoculum production by the conifer shoot blight and canker pathogens Diplodia pinea and D. scrobiculata on cones of red pine (Pinus resinosa) and jack pine (P. banksiana) were studied. Cones were collected from the ground and from canopies of red and jack pine trees in mixed stands at three sites in each of two different locations during two consecutive summers in Wisconsin. Conidia were extracted in water, quantified, germination tested, and the Diplodia species present was determined using molecular methods. At least one pathogen was detected from each tree at each site in both years. Overall, more conidia were extracted from cones from canopies than cones from the ground and from red pine cones than jack pine cones. Both total numbers of conidia extracted and proportions of cones yielding D. pinea or D. scrobiculata varied by location and pine species. Cones from either the ground or canopies can be used for surveys to detect Diplodia spp. at a given site but cones from canopies may be more useful to determine the relative abundance of potentially available inoculum of these pathogens.


2011 ◽  
Vol 101 (3) ◽  
pp. 334-339 ◽  
Author(s):  
O. Santamaría ◽  
D. R. Smith ◽  
G. R. Stanosz

Sphaeropsis sapinea sensu lato is a conifer fungal pathogen that causes shoot blight and stem cankers. Recently, the former S. sapinea has been divided into two species, Diplodia pinea and D. scrobiculata. The aims of the study were to determine the contribution of each species in disease development on red and jack pines by means of co-inoculations and molecular identifications, and to evaluate how the presence of each species affects the development and aggressiveness of the other. Symptom severity (distance below the inoculation site at which necrotic needles were observed) and identification length (the maximum distance from inoculation site from which either D. pinea or D. scrobiculata was identified using molecular methods) were recorded 4 weeks after inoculating wounded seedlings with agar plugs colonized by these pathogens. The results suggested that D. pinea was much more aggressive on both hosts than D. scrobiculata. When a seedling was co-inoculated with these pathogens, the symptom development appeared to be mainly due to D. pinea. The presence of D. pinea also interfered with the establishment of D. scrobiculata in the plant tissue. However, D. scrobiculata showed antagonism toward D. pinea. When both pathogens co-occurred in a single seedling, symptom severity caused by D. pinea was less than when D. pinea alone was present.


2005 ◽  
Vol 81 (2) ◽  
pp. 49-55 ◽  
Author(s):  
G. Laflamme ◽  
R. Blais

In the early 1980s, more than 90% of mortality caused by Gremmeniella abietina, European race, was recorded in red pine (Pinus resinosa) plantations 200 km northwest of Montreal, Quebec, Canada. Surrounding jack pines (Pinus banksiana) did not appear to be affected. Consequently, foresters began to plant the affected areas with jack pine seedlings. In 1988, plots of 100 jack pines were established in three of the four selected plantations. As reference, red pine seedlings were planted in 1989 under similar conditions in the fourth plantation. Observations were carried out annually from 1989 to 1992. Mortality of red pine seedlings reached 70% in 1992 while all jack pines on the three experimental sites were free of the disease except for a tip blight, a distinctive feature allowing race identification in the field. The North American race symptoms were present at a very low incidence, but began to increase on site I in 1992. More than 10 years after planting, the jack pine trees still show resistance to the European race of G. abietina while all the red pines died.


2001 ◽  
Vol 133 (3) ◽  
pp. 343-353 ◽  
Author(s):  
Nathan W. Siegert ◽  
Deborah G. McCullough

AbstractHost preference of the pine shoot beetle, Tomicus piniperda (L.), was investigated in two laboratory choice test studies using red pine (Pinus resinosa Ait.) (Pinaceae), jack pine (Pinus banksiana Lamb.), and Scotch pine (Pinus sylvestris L.). Host preference of parent adult beetles was evaluated using freshly cut, similarly sized logs in a wind tunnel. Parent beetles colonized Scotch pine logs significantly more often when given a choice of Scotch pine and either red pine or jack pine logs, but did not show a preference when presented with red pine and jack pine logs. Host preference of progeny adults was tested in a laboratory bioassay using current-year pine shoots. Shoot-feeding progeny adults initiated tunnels in jack pine shoots significantly more often than in Scotch pine and red pine shoots, and preferred Scotch pine over red pine shoots. Shoots with diameters of 0.4–0.5 cm were attacked most frequently, regardless of species. Results suggest that the two North American pines are suitable hosts, but T. piniperda may be most likely to colonize Scotch pine, a European species. Efforts to detect or monitor T. piniperda populations in the Great Lakes and northeastern regions should focus on areas with abundant Scotch pine brood material. Progeny that emerge from brood material, however, may be as likely to shoot-feed in jack pine as in Scotch pine.


1952 ◽  
Vol 84 (2) ◽  
pp. 59-61
Author(s):  
A. S. West

Leconte's sawfly or the red-headed pine sawfly (Neodiprion lecontei Fitch) is a common insect attacking pines in Ontario. Plantations red pine are almost invariably attacked from the time the trees have reached two to four feet in height. Periodically epidemic populations cause significant damage. The life history and habits of the species have heen described by Middleton (2) who states that this insect attacks practically all species of pine as bell as larch. Schaffner (3) also indicates that the larvae feed on a wide variety of pine and occasionally on other conifers. Red pine (Pinus resinosa Ait.) is undoubtedly the usual host, although in Ontario jack pine (Pinus banksiana Lamb.) is sometimes attacked. In 1946 evidence was secured to show that jack pine needles may be selected for oviposition even in an area where red pine foliage is plentiful. (Figure 1).


1975 ◽  
Vol 51 (2) ◽  
pp. 53-54
Author(s):  
W. Stanek

Black spruce (Picea mariana [Mill.] B.S.P.) and jack pine (Pinus banksiana Lamb.) seedlings were grown in a green-house on peat-filled flats flooded with nutrient solution or distilled water. None was aerated. However, an O2 concentration gradient existed across the flats, 3.0 – 3.7 ppm along the edges, and 1.4 – 1.9 ppm in the centers. After 4½ months seedlings of both species grew taller with nutrient solution than with distilled water. In flats supplied with nutrient solution, seedlings of both species grew taller along the edges than in the centers, whereas in flats supplied with distilled water height differential did not develop. Jack pine grew taller than black spruce under similar conditions.


1993 ◽  
Vol 20 (3) ◽  
pp. 518-527
Author(s):  
Patrick Polan ◽  
Jean Gagnon ◽  
J. Peter Jones

The Quebec government has established a program to treat industrial and domestic wastewaters. However, this program does make it necessary to dispose of large quantities of sludge. This sludge can be burned or landfilled but such solutions do not properly draw benefit from the sludge's potential as a fertilizer. There is a considerable interest in composting of the sludge. In this study, compost from the composting plant in Plattsburgh was mixed with the growing substrate normally used for the production of containerized jack pine (Pinus banksiana Lamb.) seedlings to determine if the compost could be used for the production in containers of forest seedlings. The growth of containerized seedlings produced with proportions by volume of 80% peat moss and 20% vermiculite was compared to the growth of seedlings when the peat moss (80%) was replaced by different proportions of compost (20, 40, 60, and 80%). After one growing season in tunnel, the best growth rates in terms of shoot height, root-collar diameter, and dry biomass were obtained with the control, followed in decreasing order by the treatments compost 20, 40, 60, and 80%. In this experiment, the use of compost from wastewater treatment plants reduced significantly the growth of jack pine and this can be explained mainly by the lack of nitrogen in the tissues of jack pine seedlings. However, the adjustment of nitrogen fertilization and conditions of cultivation by using compost may permit the production of containerized seedlings having the same dimensions as the controls. The seedling growth parameters when 20% compost was incorporated in the substrate were nearly the same as the control seedling. Key words: sludge, recycling, compost, substrate, container, forest seedlings, jack pine.


1966 ◽  
Vol 44 (9) ◽  
pp. 1117-1120
Author(s):  
G. B. Ouellette

Through inoculation tests in the greenhouse and in the field, the previously unknown 0 and I stages of Coleosporium viburni Arth. are shown to occur on jack pine (Pinus banksiana Lamb.). These stages are described and differences in aeciospore morphology which permit distinction on pine of this rust from Coleosporium asterum (Diet.) Syd. are discussed. The description of C. asterum is amended to include differences in aeciospore size between collections on jack and red pine (Pinus resinosa Ait.). The known distribution of C. viburni is summarized.


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