Insect toxins from spruce endophytes

2003 ◽  
Vol 81 (4) ◽  
pp. 284-292 ◽  
Author(s):  
John A Findlay ◽  
Guoqiang Li ◽  
J David Miller ◽  
Taiwo O Womiloju
Keyword(s):  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
White Spruce ◽  
Fungal Endophyte ◽  
The Novel ◽  
Macrocyclic Antibiotic ◽  
Insect Toxins ◽  
Spruce Needles

Extracts of fermentation cultures of a fungal endophyte (DAOM 221611) from spruce needles have afforded the known macrocyclic antibiotic vermiculin (1), 7α,8β,11-trihydroxydrimane (2), and eight novel 13-carbon γ-lactones, namely trans-3-methyldodec-cis-6-en-4-olide (3), trans-8-hydroxy-3-methyldodec-cis-6-en-4-olide (4), trans-8-acetoxy-3-methyldodec-cis-6-en-4-olide (5), trans-9-hydroxy-3-methyl-8-oxo-dodec-trans-6-en-4-olide (6), trans-8,9-dihydroxy-3-methyldodec-cis-6-en-4-olide (7), trans-9-hydroxy-8-oxo-3-methyldodecan-4-olide (8), trans-7,9-dihydroxy-3-methyl-8-oxo-dodecan-4-olide (9), and trans-6-hydroxymethyl-3-methyl-7-oxo-undecan-4-olide (10). A known JH III metabolism product, 10,11-dihydroxyfarnesenic acid (11), was also isolated and synthesized from farnesol. Other endophyte cultures from black spruce and white spruce afforded the novel 6,7-dihydroxy-2-propyl-2,4-octadien-4-olide (16), 5,6,8-trihydroxy-4-(1'-hydroxyethyl) isocoumarin (17) plus the known sescandelin (18), sescandelin B (19), and 4-hydroxy-2-methoxyacetanilide (20). Several of the γ-lactones showed toxicity to spruce budworm (Choristoneura fumiferana Clem.) larvae and vermiculin 1 and compound 16 were toxic to spruce budworm cells.Key words: toxigenic endophytes, insect toxins, γ-lactones, isocoumarins.

Distribution of the foliar fungal endophyte Phialocephala scopiformis and its toxin in the crown of a mature white spruce tree as revealed by chemical and qPCR analyses

2014 ◽  
Vol 44 (9) ◽  
pp. 1138-1143 ◽  
Author(s):  
Samantha L. Frasz ◽  
Allison K. Walker ◽  
Tienabe K. Nsiama ◽  
Gregory W. Adams ◽  
J. David Miller
Keyword(s):  
Picea Glauca ◽  
Limit Of Detection ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Its Region ◽  
White Spruce ◽  
Fungal Endophyte ◽  
Qpcr Assay ◽  
Small Samples ◽  
Dna Targeting

Phialocephala scopiformis Kowalski & Kehr is a foliar fungal endophyte of white spruce (Picea glauca (Moench) Voss) that produces the anti-insect compound rugulosin and other compounds in lower amounts. Seedlings inoculated with this and other toxigenic endophytes have increased tolerance to the spruce budworm Choristoneura fumiferana (Clemens, 1865). The presence of rugulosin in the diet and in needles infected by P. scopiformis reduces the growth rate of the insect. One of 300 white spruce trees inoculated as a seedling in 2001 was chosen to investigate the distribution of P. scopiformis and its principal toxin rugulosin throughout the crown. To facilitate the detection of the fungus in small samples, a qPCR assay was developed based on the ITS region of fungal ribosomal DNA targeting a genetic polymorphism unique to P. scopiformis. The assay was specific, with a method limit of detection 100 ng mycelium per gram needle sample with high reproducibility and accuracy. We found that 11 years after inoculation, P. scopiformis DAOM 229536 and its toxin were detectable in needle samples distributed throughout the crown. Of the 109 samples tested, 100% of the rugulosin-positive samples also tested positive for P. scopiformis DAOM 229536 DNA in the qPCR assay. The mean and median needle rugulosin concentrations were >2 times that required to reduce the growth of spruce budworm.

Interactions among defoliation level, species, and soil richness determine foliage production during and after simulated spruce budworm attack

2020 ◽  
Vol 50 (6) ◽  
pp. 565-580
Author(s):  
Yuanyuan Wu ◽  
David A. MacLean ◽  
Chris Hennigar ◽  
Anthony R. Taylor
Keyword(s):  
Picea Glauca ◽  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
White Spruce ◽  
Shoot Length ◽  
Balsam Fir ◽  
Site Quality ◽  
Number Of Shoots

Defoliation level and site type are thought to influence tree response during spruce budworm (Choristoneura fumiferana (Clemens)) outbreaks. We determined the effects of four manual defoliation treatments (0%, 50%, 100%, and 100% + bud removal of current foliage) for 3 years on foliage production of balsam fir (Abies balsamea (L.) Mill.), black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.), and white spruce (Picea glauca (Moench) Voss) trees on four site-quality classes. After 3 years of defoliation and 2 years of recovery, foliage biomass was reduced by 34%–98%. During defoliation, the number of shoots generally increased and shoot length of spruce generally decreased, especially on rich sites. During recovery, the number of shoots increased substantially, shoot length decreased, and bud destruction reduced the number of shoots by about 50% compared with that of trees that received the 100% defoliation treatment. Defoliation did not substantially affect needle length. Trees on rich sites had two- to fourfold greater foliage production than trees on poor sites. Effects of site and defoliation differed among species, but site quality, especially nutrition, played an important role in production of shoots and needles and the tree’s ability to withstand defoliation. Black spruce had more limited ability to recover foliage biomass, only producing more shoots, whereas balsam fir and white spruce had stronger ability to recover needle and shoot length, respectively.

Cytotoxicity and insecticidal activity of endophytic fungi from black spruce (Picea mariana) needles

1994 ◽  
Vol 40 (1) ◽  
pp. 24-27 ◽  
Author(s):  
J. A. Johnson ◽  
N. J. Whitney
Keyword(s):  
Cell Cultures ◽  
Endophytic Fungi ◽  
Picea Mariana ◽  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Sampling Period ◽  
Dry Mass ◽  
Age Classes ◽  
Spruce Needles

Hyphae and hyphal extracts from fungi isolated from inside healthy black spruce needles were assayed for their effect on spruce budworm (Choristoneura fumiferana Clem.) cell cultures and larvae. Isolates were from needles of four age-classes (current –3 years old) collected throughout a 4-month sampling period. Hyphal extracts from 21 of the 100 isolates tested were toxic to spruce budworm cell cultures and isolates from older needles (2 and 3 years old) negatively affected cells more frequently (p < 0.05) than isolates from younger needles (current and 1 year old). Hyphae from five isolates and hyphal extracts from seven increased mortality (p < 0.05) when fed to second instar larvae in a laboratory bioassay. Development was delayed and larval dry mass reduced when budworm were fed hyphae from Cryptocline abietina Petrak (isolate number 69). Larval dry mass was reduced when budworm were fed the extract from Aureobasidium pullulons (de Bary) Am. (isolate 87) but increased when fed Cryptocline abietina (isolates 40 and 80), a coelomycete (isolate 12), and Hormonema dematioides (isolates 28, 63, and 96).Key words: endophytic fungi, budworm, Choristoneura fumiferana, Picea mariana, toxicity.

Holocene occurrence ofLophodermium piceae, a black spruce needle endophyte and possible paleoindicator of boreal forest health

2007 ◽  
Vol 67 (1) ◽  
pp. 50-56 ◽  
Author(s):  
J.P. Paul Jasinski ◽  
Serge Payette
Keyword(s):  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Forest Health ◽  
Spruce Budworm ◽  
Fungal Endophyte ◽  
Tree Disease ◽  
Forest Sites ◽  
Lichen Woodland ◽  
Conifer Needle

AbstractHolocene occurrences of conifer needle endophytes have not previously been reported. We report the fossil remains ofLophodermium piceae(Fckl.) Hoehn., a fungal endophyte of black spruce (Picea mariana(Mill.) B.S.P.) needles, in macrofossils dating back to 8000 cal yr BP. Spruce budworm head capsules andL. piceaeremains were found preceding charcoal layers delineating the transformation of four spruce−moss forest sites to spruce−lichen woodland. AsL. piceaeis found solely on senescent needles, its increased presence during these transformation periods likely indicates that the forests were in decline due to the spruce budworm (Choristoneura fumiferana(Clem.)) when they burned. Future paleoecological studies incorporating needle fungi observations could be used to investigate the historical occurrence of tree disease and the role of fungi in forest health and decline.

Derivation of Pheromone-Based Larval Thresholds in Spruce Budworm Accounting for Distance to Defoliated Forest Stands

2021 ◽  
Author(s):  
Marc Rhainds ◽  
Ian DeMerchant ◽  
Pierre Therrien
Keyword(s):  
Boreal Forests ◽  
Large Scale ◽  
Choristoneura Fumiferana ◽  
Intervention Strategy ◽  
Spruce Budworm ◽  
Interactive Effects ◽  
The Novel ◽  
Forest Stands ◽  
General Guideline ◽  
Number Of Males

Abstract Spruce budworm, Choristoneura fumiferana Clem. (Lepidoptera: Tortricidae), is the most severe defoliator of Pinaceae in Nearctic boreal forests. Three tools widely used to guide large-scale management decisions (year-to-year defoliation maps; density of overwintering second instars [L2]; number of males at pheromone traps) were integrated to derive pheromone-based thresholds corresponding to specific intergenerational transitions in larval densities (L2i → L2i+1), taking into account the novel finding that threshold estimates decline with distance to defoliated forest stands (DIST). Estimates of thresholds were highly variable between years, both numerically and in terms of interactive effects of L2i and DIST, which limit their heuristic value. In the context of early intervention strategy (L2i+1 &gt; 6.5 individuals per branch), however, thresholds fluctuated within relatively narrow intervals across wide ranges of L2i and DIST, and values of 40–200 males per trap may thus be used as general guideline.

WHITE SPRUCE AND THE SPRUCE BUDWORM: DEFINING THE PHENOLOGICAL WINDOW OF SUSCEPTIBILITY

1997 ◽  
Vol 129 (2) ◽  
pp. 291-318 ◽  
Author(s):  
Robert K. Lawrence ◽  
William J. Mattson ◽  
Robert A. Haack
Keyword(s):  
Picea Glauca ◽  
High Performance ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
White Spruce ◽  
Shoot Elongation ◽  
Larval Survival ◽  
Strongly Correlated ◽  
Negative Effect ◽  
Foliar Traits

AbstractSynchrony of insect and host tree phenologies has often been suggested as an important factor influencing the susceptibility of white spruce, Picea glauca (Moench) Voss, and other hosts to the spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae). We evaluated this hypothesis by caging several cohorts of spruce budworm larvae on three white spruce populations at different phenological stages of the host trees, and then comparing budworm performance with host phenology and variation of 13 foliar traits. The beginning of the phenological window of susceptibility in white spruce occurs several weeks prior to budbreak, and the end of the window is sharply defined by the end of shoot growth. Performance was high for the earliest budworm cohorts that we tested. These larvae began feeding 3–4 weeks prior to budbreak and completed their larval development prior to the end of shoot elongation. Optimal synchrony occurred when emergence preceded budbreak by about 2 weeks. Larval survival was greater than 60% for individuals starting development 1–3 weeks prior to budbreak, but decreased to less than 10% for those starting development 2 or more weeks after budbreak and thus completing development after shoot elongation ceased. High performance by the budworm was most strongly correlated with high levels of foliar nitrogen, phosphorous, potassium, copper, sugars, and water and low levels of foliar calcium, phenolics, and toughness. These results suggest that advancing the usual phenological window of white spruce (i.e. advancing budbreak prior to larval emergence) or retarding budworm phenology can have a large negative effect on the spruce budworm’s population dynamics.

LONG TERM STUDY OF THE EFFECTIVENESS OF AERIAL APPLICATION OF BACILLUS THURINGIENSIS – ACEPHATE COMBINATIONS AGAINST THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1977 ◽  
Vol 109 (9) ◽  
pp. 1239-1248 ◽  
Author(s):  
O. N. Morris
Keyword(s):  
Bacillus Thuringiensis ◽  
Choristoneura Fumiferana ◽  
Larval Mortality ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
White Spruce ◽  
Balsam Fir ◽  
Population Densities ◽  
Long Term Study

AbstractBacillus thuringiensis (Dipel® 36B) mixed with a sublethal concentration of acephate (Orthene®) (O, S-dimethyl acetylphosphoramidothioate), an organophosphorous insecticide, was applied at 2.35–14 l./ha to white spruce (Picea glauca) and balsam fir (Abies balsamea) trees infested with spruce budworm, Choristoneura fumiferana (Clem.). The treatment rate was 20 Billion International Units of B. thuringiensis (B.t.) activity with or without 42 g of active ingredient of acephate/ha.The ground deposit of the standard Dipel wettable powder formulation was 12% of emitted volume compared with 21–32% for the Dipel 36B flowable. The viability of B.t. spores was drastically reduced after 1 day of weathering but a high level of biological activity by the spore–crystal complex persisted for up to 20 days post-spray due probably to crystal activity.The addition of about 10% of the recommended operational rate of acephate to the B.t. suspension increased larval mortality by 34% when applied at 4.7 l./ha. Reductions in budworm populations were 97–99% in B.t. + acephate plots and 86–90% in B.t. alone plots.Plots with moderate budworm densities of up to 27 larvae/100 buds on white spruce and 36/100 on balsam fir were satisfactorily protected from excessive defoliation in the year of spray by B.t. with or without acephate. Plots with higher population densities were not satisfactorily protected based on the branch sample examination but aerial color photographs indicated good protection to the top third of the trees. Population declines were greater and defoliation and oviposition were lower in the treated plots than in the untreated checks 1 year later without further treatment. Two years later the larval population densities in all plots were low but the density was twice as high in the untreated check as in the treated plots, indicating long term suppression by the treatments. Defoliation was negligible in all plots.The treatments had no deleterious effect on spruce budworm parasitism. The data indicate that the integrated approach using Bacillus thuringiensis – chemical pesticide combinations is a viable alternative to the use of chemical pesticides alone in spruce budworm control. Large scale testing is now warranted.

scholarly journals Genetic control and evolutionary potential of a constitutive resistance mechanism against the spruce budworm (Choristoneura fumiferana) in white spruce (Picea glauca)

Heredity ◽  
2018 ◽  
Vol 121 (2) ◽  
pp. 142-154 ◽  
Author(s):  
Claudia Méndez-Espinoza ◽  
Geneviève J. Parent ◽  
Patrick Lenz ◽  
André Rainville ◽  
Laurence Tremblay ◽  
...  
Keyword(s):  
Genetic Control ◽  
Picea Glauca ◽  
Choristoneura Fumiferana ◽  
Resistance Mechanism ◽  
Spruce Budworm ◽  
White Spruce ◽  
Evolutionary Potential ◽  
Constitutive Resistance

EFFECT OF RH-5992, A NONSTEROIDAL ECDYSONE AGONIST, ON THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE): LABORATORY, GREENHOUSE, AND GROUND SPRAY TRIALS

1997 ◽  
Vol 129 (5) ◽  
pp. 871-885 ◽  
Author(s):  
A. Retnakaran ◽  
L.F.R. Smith ◽  
W.L. Tomkins ◽  
M.J. Primavera ◽  
S.R. Palli ◽  
...  
Keyword(s):  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Peak Level ◽  
White Spruce ◽  
Head Capsule ◽  
Entire Body ◽  
Chitin Synthesis ◽  
Synthesis Inhibitor ◽  
Receptor System ◽  
Ecdysone Agonist

AbstractIngestion of 0.1 μg of RH-5992, tebufenozide, by early 6th instar larvae of the spruce budworm, Choristoneura fumiferana (Clem.), prior to the appearance of the ecdysone peak in the hemolymph, resulted in the induction of a precocious incomplete moult that was lethal. The larvae stopped feeding within 8 h post ingestion and remained quiescent just as they do in preparation for a normal moult. Head capsule slippage started at 12 h post ingestion, became pronounced by 24 h, and by 48 h an untanned new head capsule was visible behind the old one. The lack of tanning of the new cuticle was due to the failure of dopadecarboxylase gene expression. Although the old cuticle was loose around the entire body, indicating that apolysis had occurred, there was no evidence of ecdysis of the old cuticle, suggesting that eclosion hormone was probably not released. Earlier instars required a lower dose than the later ones to elicit an "all or none" type of moulting response. The most effective routes of entry were by intrahemocoelic injection, followed by ingestion. Topical application was effective only when nonaqueous carriers such as acetone or dimethyl sulfoxide were used. The larvae were unable to discriminate between treated and untreated diet over a 48-h period. The transcription factor, Choristoneura hormone receptor 3, which is normally expressed at the onset of the hemolymph ecdysone peak, was expressed in the epidermis 1 h post ingestion of RH-5992, reached a peak level by 3 h, and became undetectable by 24 h, confirming that this analogue acts through the ecdysone receptor system. Greenhouse tests using potted white spruce trees sprayed with RH-5992 and colonized with 4th-instar spruce budworm indicated that field dosages of 35, 70, 140, and 280 g/ha would all be effective. Ground spray trials conducted in a spruce budworm infested white spruce stand in Zee Casault, Gaspé, Quebec, using a backpack sprayer showed that ≥ 70 g/ha of RH-5992 reduced the insect population by 100% with very little defoliation and was better than Chlorfluazuron® (an analogue of the chitin synthesis inhibitor, diflubenzuron or Dimilin®) treatment, which was used as a positive control. The unique mode of action of this ecdysone agonist and its effectiveness as an environmentally benign control agent for the spruce budworm are discussed.

Sign in / Sign up

Export Citation Format

Share Document