Early symptoms and resistance of lodgepole pine seedlings inoculated with western gall rust

1992 ◽  
Vol 70 (6) ◽  
pp. 1274-1278 ◽  
Author(s):  
H. O. Kojwang ◽  
B. J. van der Kamp
Keyword(s):  
Pinus Contorta ◽  
Rust Fungus ◽  
Good Prediction ◽  
Gall Formation ◽  
Inoculum Concentration ◽  
Early Symptoms ◽  
Pine Seedlings ◽  
Endocronartium Harknessii ◽  
One Year ◽  
Two Stages

One-year-old seedlings in 10 open-pollinated Pinus contorta families were inoculated with spores of the rust fungus Endocronartium harknessii at two stages of seedling maturity and two levels of inoculum concentration. The early symptoms (general red stain, red flecks, red streaks) that appeared on the seedlings were recorded 2, 4, and 8 weeks after inoculation, while the number of galls was recorded 1 year after inoculation. The frequency of general red stain and red flecks varied significantly among families. Resistance of families as percent of seedlings producing galls also varied significantly. The frequency of early symptoms was only poorly correlated with family resistance. Also, the occurrence of early symptoms on individual seedlings did not give a good prediction of gall formation on them. These results suggest that early symptoms cannot accurately identify resistant families or individuals. Key words: Endocronartium harknessii, Pinus contorta, symptoms, resistance.

Early symptom development in lodgepole pine seedlings infected with Endocronartium harknessii

1990 ◽  
Vol 68 (2) ◽  
pp. 270-277 ◽  
Author(s):  
Eric A. Allen ◽  
P. V. Blenis ◽  
Y. Hiratsuka
Keyword(s):  
Pinus Contorta ◽  
Rust Fungus ◽  
Infected Tissue ◽  
Cortical Cells ◽  
Subsequent Formation ◽  
Early Symptom ◽  
Pine Seedlings ◽  
Endocronartium Harknessii ◽  
Periderm Formation ◽  
Lignin Deposition

Six-week-old Pinus contorta seedlings were inoculated with spores of the western gall rust fungus Endocronartium harknessii. Of 660 seedlings inoculated, 174 showed early symptoms and were sampled for histological observation in the 7 weeks following inoculation. Pigmentation of epidermal cells was the first externally visible response to infection, generally occurring 14–28 days after inoculation. Developing symptoms were extremely variable, ranging from little or no visible response to severe necrosis. The appearance of external symptoms was largely due to changes occurring in underlying infected cortical cells such as the production of phenolic compounds, necrophylactic periderm, or necrotic tissue. Intercellular lignin deposition was observed in infected tissue and was thought to be associated with necrophylactic periderm formation. Suppression of normal exophylactic periderm development was evident in virtually all infected tissue zones. Infection of the vascular cambium occurred as early as 21 days after inoculation and resulted in the subsequent formation of distorted xylem tracheids typical of gall tissue.

Histological evidence of resistance to Endocronartium harknessii in Pinus contorta var. latifolia

1990 ◽  
Vol 68 (8) ◽  
pp. 1728-1737 ◽  
Author(s):  
E. A. Allen ◽  
P. V. Blenis ◽  
Y. Hiratsuka
Keyword(s):  
Pinus Contorta ◽  
Secondary Xylem ◽  
Rust Fungus ◽  
Cortical Lesions ◽  
Gall Formation ◽  
Cortical Cells ◽  
Endocronartium Harknessii ◽  
Infected Cells ◽  
Initial Resistance ◽  
Resistance To Infection

Resistance to the western gall rust fungus, Endocronartium harknessii, was observed in 3-, 10-, 20-, and 33-month-old greenhouse-grown seedlings of lodgepole pine (Pinus contorta var. latifolia). Three sites of resistance were identified: epidermal, cortical, and cambial. In cases of epidermal resistance, penetration of the epidermis occurred, but infection was prevented by an apparent hypersensitive response. Cortical resistance occurred where infected cells in the cortex were successfully isolated by necrophylactic periderm and the infected tissue was exfoliated with the rhytidome. In cambial resistance, infections progressed to the vascular cambium where infected cells and cambial initials were inactivated. This resulted in abnormal secondary xylem development, characterized by a zone of pathological tissue extending from the pith to the epidermis. In a number of infected seedlings, cambial function was restored and infected lesions were overgrown. Live mycelium was often maintained in cortical lesions and in some cases reinvaded healthy cortical cells. These latent-type infections resulted in the initiation of gall formation up to 1 year after initial resistance to infection occurred. Key words: tree improvement, western gall rust, pine stem rust.

scholarly journals Lodgepole Pine and White Spruce Establishment After Glyphosate and Fertilizer Treatments of Grassy Cutover Forest Land.

1979 ◽  
Vol 55 (3) ◽  
pp. 102-105 ◽  
Author(s):  
D. G. Blackmore ◽  
Wm. G. Corns
Keyword(s):  
Picea Glauca ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
White Spruce ◽  
Forest Land ◽  
Vegetation Control ◽  
Calamagrostis Canadensis ◽  
Pine Seedlings ◽  
One Year ◽  
Spring Planting

Perennial herbaceous vegetation, mainly marsh reed grass, (Calamagrostis canadensis (Michx) Beauv.), was sprayed with glyphosate on the day before planting one-year-old plugs of lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) and white spruce (Picea glauca (Moench) Voss) on cutover forest land north of Edson, Alberta. Spraying at 4.5 kg ai/ha, included spot and strip applications in June 1976, compared with unsprayed scalps and controls. At the same time, all treatments were repeated plus a 9 g, 22-8-2 fertilizer tablet for each seedling. Another experiment at the same site, begun on August 1, 1976, compared scalp, unfertilized control and glyphosate strip treatments, followed by planting of pine seedlings the day after spraying 4.5 kg ai/ha glyphosate. An adjacent experiment, also commenced on August 1, included dosages of 1.1 to 5.6 kg ai/ha with planting of pine seedlings in 4.5 kg/ha and in control plots in May 1977. August application of 2.2 kg/ha provided excellent initial vegetation control, as effective as the larger amounts applied at that time, and was superior during the first 12 months to 4.5 kg/ha applied in June. Twenty-six months after the spring planting new shoot growth of fertilized pine in the glyphosate strips was statistically significantly greater than that for all other treatments and growth in fertilized scalps was also very good. At the same time leader growth of spruce in fertilized scalps was significantly greater than that for other treatments but growth in glyphosate strips did not exceed that of unfertilized controls. Contrary to results of spring planting, there was marked injury and mortality of pine planted in August in glyphosate plots which had been sprayed on the preceding day. Seedlings planted in glyphosate-treated strips nine months after the August spraying exceeded the growth of control plants but not until the year after they were planted.

Ectomycorrhizas of lodgepole pine (Pinus contorta) seedlings originating from seed in southwestern Alberta cut blocks

1998 ◽  
Vol 76 (2) ◽  
pp. 213-217 ◽  
Author(s):  
S M Bradbury
Keyword(s):  
Seed Germination ◽  
Pinus Contorta ◽  
Host Plants ◽  
Lodgepole Pine ◽  
Sampling Time ◽  
Pine Seedlings ◽  
Seedling Roots ◽  
Fungal Associates ◽  
One Year

Lodgepole pine (Pinus contorta Dougl. ex Loud.) seedlings, originating from seed in three southwestern Alberta cut blocks, were sampled to identify their ectomycorrhizal associates. Fourteen ectomycorrhizal taxa were identified, 10 were common to all three cut blocks, and 12 to two cut blocks. Individual seedlings were colonized by two fungal associates on average and never had more than six fungal associates at one sampling time. Total percent colonization of seedling roots was greater than 50% one year after seed germination and greater than 90% two years after seed germination. Species richness increased throughout the course of the study; however, all but two ectomycorrhizal taxa were found in mature forests nearby. Typical late-stage ectomycorrhizal fungi colonized regenerating lodgepole pine seedlings in the absence of refuge host plants; therefore, either these fungi remained viable in situ between harvesting and regeneration or they migrated back into the cut block once revegetation was initiated.Key words: lodgepole pine seedlings, ectomycorrhiza, percent relative abundance, Alberta cut blocks.

Susceptibility of Pinus contorta - Pinus banksiana complex to Endocronartium harknessii: host-pathogen interactions

1999 ◽  
Vol 77 (7) ◽  
pp. 1035-1043 ◽  
Author(s):  
Rong-Cai Yang ◽  
Zhihong Ye ◽  
Yasu Hiratsuka
Keyword(s):  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Rust Fungus ◽  
Jack Pine ◽  
Natural Hybridization ◽  
Host Group ◽  
Group Interactions ◽  
Endocronartium Harknessii ◽  
Rust Susceptibility

Lodgepole (Pinus contorta Dougl. ex Lound.) and jack (Pinus banksiana Lamb.) pines occur sympatrically and hybridize in central and northwestern Alberta, providing opportunities for studying unique ecological and evolutionary interactions. We conducted a greenhouse inoculation experiment to investigate interactions between 40 populations of lodgepole and jack pines and their putative hybrids across this hybrid zone and two sources of the western gall rust fungus, Endocronartium harknessii (J.P. Moore) Y. Hiratsuka, one from lodgepole pine and the other from jack pine. Rust susceptibility and height were assessed when the seedlings were 6 months and 1 year old. Lodgepole pine and the hybrids were significantly more susceptible to the rust infection than jack pine. Jack pine grew significantly faster than the hybrids and lodgepole pine. In addition, the seedlings infected with spores from lodgepole pine grew significantly slower than those with spores from jack pine. While the overall rust scores indicated that spores from lodgepole pine was more virulent to the hosts than those from jack pine, both spore sources were better adapted to their own host species, causing significant spore source × host group interactions. However, such host specificity in the western gall rust is far from stabilized (equilibrium) because of continued gene exchanges among the two parental species and their hybrids.Key words: Pinus contorta - Pinus banksiana complex, western gall rust, natural hybridization, coevolutionary genetics.

Random amplified polymorphic DNA variability among geographic isolates of western gall rust fungus in Canada

2001 ◽  
Vol 31 (8) ◽  
pp. 1304-1311 ◽  
Author(s):  
Changxi Li ◽  
Francis C Yeh ◽  
Yasu Hiratsuka
Keyword(s):  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Random Amplified Polymorphic Dna ◽  
Rust Fungus ◽  
Jack Pine ◽  
Fungal Isolates ◽  
Rapd Pattern ◽  
Endocronartium Harknessii ◽  
East West

Geographic variability among western gall rust (WGR) fungus (Endocronartium harknessii (J.P. Moore) Y. Hiratsuka) was studied by random amplified polymorphic DNA (RAPD). Samples were taken from lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) host at four locations in British Columbia and Alberta and from jack pine (Pinus banksiana Lamb.) host at nine locations in Alberta, Saskatchewan, Manitoba, and Ontario. Of 90 random oligonucleotide primers screened, 9 were chosen for analysis. These nine primers consistently amplified 41 sharp and reproducible RAPDs (fragments) of the WGR fungal isolates over several independent runs. Eighteen of the 41 RAPDs were polymorphic (showing the presence of both marker and null phenotypes), of which 15 could discriminate WGR isolates of lodgepole pine hosts from jack pine ones. Of these 15 RAPDs, five were unique to isolates of lodgepole and five to jack pine. The remaining five RAPDs were significantly heterogeneous in the RAPD frequency between WGR isolates of the two host origins. The RAPD pattern of WGR isolates from lodgepole pine was uniform. However, isolates from jack pine differed significantly in the frequency of four RAPDs among locations, with an east-west trend of decreasing similarity in RAPD. Analysis of molecular variance apportioned 76.3, 14.4, and 9.3% of the total RAPD variability to differences among hosts, to differences among locations within hosts, and to differences within locations, respectively. The large differentiation between WGR fungal isolates sampled in lodgepole pine and jack pine hosts might suggest that selective pressure for host specificity in sampled populations was strong.

THE RELATION OF GROWTH REGULATORS TO THE DEVELOPMENT OF SYMPTOMS AND THE EXPRESSION OF STEM RESISTANCE IN WHITE PINE INFECTED WITH BLISTER RUST

1967 ◽  
Vol 45 (4) ◽  
pp. 501-513 ◽  
Author(s):  
Michael G. Boyer
Keyword(s):  
Gibberellic Acid ◽  
Growth Regulators ◽  
Indoleacetic Acid ◽  
Rust Fungus ◽  
Gall Formation ◽  
White Pine ◽  
Anatomical Studies ◽  
Blister Rust ◽  
Pine Seedlings ◽  
Stem Resistance

The application of the growth regulators indoleacetic acid and gibberellic acid to stems of white pine seedlings produced many symptoms characteristic of the disease caused by the blister rust fungus, thus suggesting their possible involvement in gall formation. When a kinin-like compound, benzimidazole, was applied, a wound periderm was initiated in seedlings infected with the blister rust fungus but not in healthy seedlings. This effect was augmented by indoleacetic acid and gibberellic acid. It seems to be a phenomenon very similar to that observed in stem-resistant white pine, and a possible relationship is proposed based on anatomical studies.

scholarly journals Record of the circumstances of falls in the community: perspective in the Iberian Peninsula

2018 ◽  
Vol 26 (0) ◽  
Author(s):  
Maria de Fátima Araújo ◽  
Nilza Nogueira Caldevilla ◽  
Candida Maciel ◽  
Felicidade Malheiro ◽  
María Aurora Rodríguez-Borrego ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Health Professionals ◽  
Assessment Instruments ◽  
Structured Interviews ◽  
Basic Health ◽  
Risk Of Falls ◽  
Quantitative Descriptive ◽  
One Year ◽  
Two Stages ◽  
Basic Health Units

ABSTRACT Objective: to determine the diagnosis of the situation regarding documentation of falls and risk of falls in people older than 75 years in basic health units in Spain and Portugal. Method: mixed exploratory study in two stages: (i) quantitative descriptive of randomly selected fall records produced in one year (597 records; 197 Spanish and 400 Portuguese); and (ii) qualitative, with the purpose of knowing the perception of health professionals employing semi-structured interviews (72 professionals, 16 Spanish and 56 Portuguese). The study areas were two basic health units in southern Spain and northern Portugal. Results: in the fall records, the number of women was higher. The presence of fall was associated with the variables age, presence of dementia, osteoarticular disease, previous falls and consumption of antivertiginous medication. Health professionals perceived an absence of risk assessment instruments, as well as lack of prevention programs and lack of awareness of this event. Conclusion: falls are perceived as an area of priority attention for health professionals. Nonetheless, there is a lack of adherence to the registration of falls and risk assessment, due to organizational, logistical and motivational problems.

scholarly journals Slow-release fertilizers and possibilities of their utilizing in nursery

2004 ◽  
Vol 52 (2) ◽  
pp. 155-164
Author(s):  
Petr Salaš
Keyword(s):  
Slow Release ◽  
Ornamental Plants ◽  
Woody Species ◽  
Soil Surface ◽  
Berberis Thunbergii ◽  
Slow Release Fertilizers ◽  
Picea Omorika ◽  
One Year ◽  
Two Stages

Reserve, slow-release fertilizers (SRF) enable to simplify the whole system of plant nutrition and fertilisation. Tabletted fertilizers of the Silvamix series represent a prospective product of Czech provenience. At our university, these fertilizers have been tested and used since the year 1991. Ornamental woody species grown in containers were investigated in two stages. Experiments with ornamental plants were established using one-year-old cuttings and seedlings of the following deciduous and evergreen woody species:Cotoneaster dammeri Skogholm,Berberis thunbergii,Potentilla fruticosa Snowflake,Ligustrum vulgare AtrovirensandPicea omorika. After planting into containers, fertilizers in the dose of 1 tablet (i.e. 10 g) per litre of substrate were applied either to roots level or on the soil surface in the container. Silvamix in the dose of 5 g.l-1was used as the tested fertilizer in the second stage. It was applied during the planting in the form of tablets and/or a powder. Control plants were fertilized in the course of growing season using a common agricultural fertilizer Cererit Z. The annual plants increments were measured. These experiments demonstrated a long-term optimum effect of this product on woody species and an equal quality and efficiency of its tabletted and powdered forms.

scholarly journals Incorporation of radioactive products of photosynthesis into lignin and cellulose of Scots pine (Pinus sihestris L.) seedlings

2015 ◽  
Vol 42 (4) ◽  
pp. 555-565
Author(s):  
Igor Góral
Keyword(s):  
Scots Pine ◽  
Growth Stages ◽  
Pine Seedlings ◽  
Photosynthetic Products ◽  
One Year ◽  
Different Growth Stages

Distribution of radioactive photosynthetic products as well as their utilization in biosynthesis of lignin and cellulose in one-year-old pine seedlings was investigated at different growth stages. It was found that time of metabolization and the rate of photosynthetic products incorporation into lignin and cellulose depends on the organ and -on the kind of polymer synthetized.

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