AN IMPROVED LABORATORY METHOD FOR REARING LARGE NUMBERS OF SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1970 ◽  
Vol 102 (9) ◽  
pp. 1111-1117 ◽  
Author(s):  
Dail Grisdale
Keyword(s):  
Choristoneura Fumiferana ◽  
Adult Emergence ◽  
Laboratory Method ◽  
Artificial Lighting ◽  
Feeding Sites ◽  
Plastic Bags ◽  
Large Numbers ◽  
Newly Hatched Larvae ◽  
Anti Fungal ◽  
Selection Of

AbstractLarvae are reared on a synthetic diet in 1 oz. ribbed plastic cups. To eliminate the task of placing individual larvae on food, small gauze patches containing 25–40 larvae are placed in the cups prior to emergence from hibernacula. Larvae establish feeding sites between the ribs and are relatively undisturbed by others in the cup until the fifth instar. For maintenance of rearing stock the number of larvae is reduced to six to eight per cup, and they are allowed to pupate in the cups. Up to 100 pairs of pupae are placed in screened cages for adult emergence, mating, and oviposition. When the adults emerge balsam fir foliage is introduced and most of the eggs are deposited on the needles. Needles or twigs with egg clusters are transferred to large dishes the inside of which is painted black. The dish is tightly sealed with parafilm to which small gauze patches are attached and then placed under artificial lighting. The newly-hatched larvae are attracted toward the light and spin hibernacula in the gauze. The parafilm and gauze are sealed in plastic bags for cold storage treatment. By this system up to 10,000 larvae per week are easily produced.A discussion on the selection of rearing stock, rearing conditions, rearing containers, and the use of anti-fungal agents is included in the report.

scholarly journals First Report of Pycnostysanus azaleae on Rhododendron in Italy

Plant Disease ◽  
2002 ◽  
Vol 86 (5) ◽  
pp. 560-560
Author(s):  
A. Garibaldi ◽  
G. Gilardi ◽  
D. Bertetti ◽  
M. L. Gullino
Keyword(s):  
The United States ◽  
Flower Buds ◽  
First Report ◽  
Flower Production ◽  
Plastic Bags ◽  
Large Numbers ◽  
Wide Range ◽  
Sterile Needle ◽  
Extensive Necrosis ◽  
Selection Of

Rhododendron species cultivation has a long history in northern Italy, where a wide selection of cultivars and hybrids is grown. In spring 2001, a previously unknown bud blast was observed on several rhododendron cultivars growing in gardens and parks in the Province of Biella, Italy. Flower petioles and twigs, but not leaves, showed extensive necrosis, and flower production was reduced. The first symptoms on infected flower buds are brown necrotic areas near the base, which increase in size until the whole bud appears brown and water-soaked. Infected buds shrink, but do not rot or disintegrate, and remain on the bush. Coremia (2.0 mm high and 0.5 mm wide), which appeared as black specks on outer bud scales, produced large numbers of spherical spores apically that measured 3.6 to 5.5 μm in diameter. The fungus Pycnostysanus azaleae (1) was consistently isolated after disinfested infected buds (1 min in 5.15% commercial NaOCl solution) were cultured on potato dextrose agar amended with streptomycin sulfate at 100 mg/liter. Pathogenicity of three isolates of P. azaleae was confirmed by inoculating with a spore suspension 30 buds of 2 rhododendron plants (cv. Rosso scuro grande tardiva) grown in containers (14 cm diameter). Buds were punctured with a sterile needle before inoculation. Noninoculated plants served as controls. Wounded buds were covered with plastic bags to maintain high relative humidity, and all plants were maintained in growth chambers at 20°C for 9 days, and then transferred outdoors where temperatures were 20 to 25°C. Inoculated plants developed typical bud symptoms 20 days after inoculation, with 80% of inoculated buds showing symptoms. Control plants remained symptomless. The pathogen was consistently reisolated from artificially inoculated plants. In garden observations, different cultivars showed a wide range of susceptibility to the pathogen, mainly related to their flowering period. To our knowledge, this is the first report of the presence of P. azaleae in Italy. Outbreaks of P. azaleae were previously reported in the United States (1), United Kingdom (2), and Germany (3). References: (1) W. H. Davis. Phytopathology 29:517, 1939. (2) P. J. Howell and R. K. S. Wood. Ann. Appl. Biol. 50:723, 1962. (3) W. Schmalscheidt. Immergrune Blater 26:35, 1985.

scholarly journals Impact of conventional insecticides on two bollworms and their indirect effects on the ectoparasitoid, Bracon brevicornis (Wesmael) (Hymenoptera: Braconidae)

2019 ◽  
Vol 43 (1) ◽  
Author(s):  
Mervat A. Kandil ◽  
Hemat Z. Moustafa
Keyword(s):  
Indirect Effects ◽  
Larval Mortality ◽  
Adult Emergence ◽  
Immature Stage ◽  
Pectinophora Gossypiella ◽  
Earias Insulana ◽  
Pupal Development ◽  
Percentage Mortality ◽  
Biological Aspects ◽  
Newly Hatched Larvae

Abstract Background Cotton bollworms such as Pectinophora gossypiella and Earias insulana are serious pests which destroy the cotton plant, and Bracon brevicornis is a parasitoid which attacked the larvae of bollworms. Results In this study, experiments were performed to investigate and evaluate the toxicity of etofenprox and chlorpyrifos insecticides against newly hatched larvae of Pectinophora gossypiella and Earias insulana. Some biological aspects of compound effects on larval and pupal duration, percentage of mortality, and percentage of adult emergence which resulted from treated newly hatched larvae were studied. The results revealed that LC50 was 0.7 and 0.87 ppm when P. gossypiella was treated with etofenprox and chlorpyrifos, respectively, while LC50 was 0.09 and 0.73 ppm when E. insulana was treated with etofenprox and chlorpyrifos, respectively. The obtained results showed that the percentage of mean larval mortality was 65.0 and 63.0% for treated P. gossypiella, while it was 71.0 and 66.0% for treated E. insulana. The corresponding figure for pupal percentage mortality was 8.0 and 10.0% for treated P. gossypiella, but it was 5.0 and 2.0% for treated E. insulana, with etofenprox and chlorpyrifos, and a prolongation effect in larval and pupal development (total immature stage) resulted from treated both bollworms as follows: 35.5 and 32.4 days for treated P. gossypiella compared with 21.9 days in control and 34.7 and 23.2 days for treated E. insulana compared with 23.1 days in control. The indirect effect of etofenprox and chlorpyrifos on the total immature stage of Bracon brevicornis was 18.2 and 19.5 days compared with 14.3 days in control when B. brevicornis parasitized on P. gossypiella larvae while it was 19.8 and 20.6 days compared with 15.2 days when B. brevicornis parasitized on E. insulana larvae. Conclusion The life cycle of B. brevicornis after parasitism on P. gossypiella and E. insulana larvae treated with etofenprox and chlorpyrifos were increased than the control larvae.

scholarly journals Biological activities of spores and metabolites of some fungal isolates on certain aspects of the spiny bollworms Earias insulana (Boisd.) (Lepidoptera: Noctuidae)

2019 ◽  
Vol 29 (1) ◽  
Author(s):  
Eman Mohammed Abd-ElAzeem ◽  
Warda Ahmed Zaki El-Medany ◽  
Hend Mohammed Sabry
Keyword(s):  
Biological Activities ◽  
Larval Mortality ◽  
Adult Emergence ◽  
Pupal Weight ◽  
Earias Insulana ◽  
Dead Larva ◽  
Fungal Isolates ◽  
Protease Enzyme ◽  
Newly Hatched Larvae ◽  
Lepidoptera Noctuidae

AbstractBiological activities of spores and metabolites of some fungi isolated from dead larva of the spiny bollworms (SBW), Earias insulana (Boisd.) (Lepidoptera: Noctuidae), against the newly hatched larvae of the pest were carried out. Results showed that the fungi Metarhizium anisopliae, Acremonium sp., and Paecilomyces variotii had affected the newly hatched larvae of (SBW). Acremonium sp. was the most potent one as it had the highest newly hatched larval mortality percentage (65 and 58.33%) for its spore suspension and metabolites, respectively, while the lowest one (41%) was for P. variotii metabolites. Also, spore suspensions of the all fungal isolates had the highest larval mortality than fungal metabolites. Studying the enzymatic activity showed that Acremonium sp. produced protease enzyme on media containing gelatin, which caused the highest larval mortality (72.22%).These isolates showed different effects on all stages of the pest and decreased pupal weight, adult emergence percentages, deposited eggs, and hatchability percentages than the control. Identification of Acremonium sp. EZ1 was confirmed using 18 s rRNA and its accession number MN25101.

FACTORS AFFECTING ADULT EMERGENCE AND MATING BEHAVIOR OF THE EASTERN SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1975 ◽  
Vol 107 (9) ◽  
pp. 967-977 ◽  
Author(s):  
C. J. Sanders
Keyword(s):  
Field Experiments ◽  
Choristoneura Fumiferana ◽  
Adult Emergence ◽  
Spruce Budworm ◽  
Field Conditions ◽  
Continuous Illumination ◽  
Degree Days ◽  
Factors Affecting ◽  
Eastern Spruce Budworm ◽  
Duration Of Copulation

AbstractLaboratory and field experiments indicate that the female spruce budworm (Choristoneura fumiferana (Clem.)) pupal stadium requires approximately 122C degree-days above a threshold of 7.2 °C (45°F), the male 124. Emergence time on any given day depends on temperature but is independent of photoperiod. Under field conditions male and female budworm mate only once per 24-h period. In the laboratory under continuous illumination females mate repeatedly and males readily mate a second time within a few hours, but the duration of the second copulation is abnormally long. The probability of multiple matings under field conditions is reduced by the restricted period of sexual activity coupled with the duration of copulation and the lower competitiveness of mated insects. Antennae are essential to the male for successful copulation.

Changing Patterns in the Late Pleistocene/Early Holocene Prehistory of Southern Africa as Seen from the Nelson Bay Cave Stone Artifact Sequence

1978 ◽  
Vol 10 (1) ◽  
pp. 84-111 ◽  
Author(s):  
Janette Deacon
Keyword(s):  
Southern Africa ◽  
Sensu Stricto ◽  
Middle Stone Age ◽  
Stone Age ◽  
Faunal Remains ◽  
Later Stone Age ◽  
Large Numbers ◽  
Changing Patterns ◽  
Selection Of ◽  
Stone Artifact

The dating of the Stone Age sequence in southern Africa has been considerably revised over the last decade, and one of the anomalies which has resulted is that the Middle Stone Age, now dated to beyond 30,000 B.P., does not immediately precede the Later Stone Agesensu stricto. The excavation and analysis of occupation horizons dating between the most recent Middle Stone Age assemblages and the Holocene is therefore of particular interest. Nelson Bay Cave, situated on the southern coast of South Africa, contains deposits which partly fill the “gap” between the Middle and Later Stone Ages, and the occupation horizons dating between about 18,000 and 5000 years ago are described in this paper. Changes in the habitat in the vicinity of the site caused by sea-level and vegetation changes coincident with the amelioration of temperatures at the end of the Pleistocene are clearly marked in the faunal remains at the site. Largely correlated with the faunal changes (which includes the introduction of marine resources to the cave at about 12,000 B.P.) are changes in the stone artifact assemblages. Three industries are recognized in the sequence: the Robberg, characterized by microbladelets produced from bladelet cores and a few small scrapers and backed tools; the Albany, characterized by large scrapers and an absence of backed tools; and the Wilton, characterized by a variety of Formal Tools including relatively large numbers of small scrapers and backed tools. These changes in artifact-manufacturing traditions are interpreted as signaling adjustments to changing environmental conditions. An explanation for these adjustments is not sought in a simple cause-and-effect relationship between the environment and the cultural response; artifact changes are seen instead as the result of a twofold process, with the environment acting as an external stimulus to change, and the direction of the artifact change governed by the selection of a range of possibilities offered by the technology of the Later Stone Agesensu latothat was widespread in subequatorial Africa during the last 20,000 years.

Selection of feeding sites by horses at pasture: Testing the anti-parasite theory

2007 ◽  
Vol 108 (3-4) ◽  
pp. 288-301 ◽  
Author(s):  
Geraldine Fleurance ◽  
Patrick Duncan ◽  
Herve Fritz ◽  
Jacques Cabaret ◽  
Jacques Cortet ◽  
...  
Keyword(s):  
Feeding Sites ◽  
Selection Of

scholarly journals A Quantitative Method for Determining Soil Populations of Streptomyces and Differentiating Potential Potato Scab-Inducing Strains

Plant Disease ◽  
1998 ◽  
Vol 82 (6) ◽  
pp. 631-638 ◽  
Author(s):  
Kenneth L. Conn ◽  
Edlira Leci ◽  
Giora Kritzman ◽  
George Lazarovits
Keyword(s):  
Potato Scab ◽  
Colony Morphology ◽  
Malt Extract ◽  
Facilitated Diffusion ◽  
Thaxtomin A ◽  
Streptomyces Spp ◽  
Plastic Bags ◽  
Large Numbers ◽  
History Of ◽  
Layer Chromatography

A procedure is described for estimating Streptomyces populations in soil. Soils are air-dried, 10g quantities are shaken in plastic bags containing 0.1% water agar and homogenized with a Stomacher homogenizer, serial dilutions are plated on a semi-selective culture (STR) medium and incubated for 2 weeks at 22°C, and the Streptomyces colonies are enumerated. Use of STR medium reduced the bacterial and fungal colonies recovered from soil to levels below that of the Streptomyces spp. while not affecting the number of Streptomyces colonies compared with those enumerated on yeast malt extract medium. A procedure for screening large numbers of Streptomyces strains for thaxtomin production, a phytotoxin recognized as a virulence marker in S. scabies, is also described. Strains are grown on oatmeal medium, and the thaxtomin is extracted from the medium by facilitated diffusion and detected by miniature thin layer chromatography. S. scabies and S. acidiscabies strains (approximately 130 from Ontario and 70 from other locations in North America) that produced thaxtomin did not form aerial mycelia or sporulate on STR medium within 2 weeks at 22°C. Ontario S. scabies strains that produced thaxtomin A also produced melanin on STR medium. All S. scabies strains from scab lesions that produced thaxtomin A had this colony morphology, whereas only 4 to 9% of strains from soil with this colony morphology produced thaxtomin A. Using these procedures, we determined that the population of thaxtomin-producing S. scabies in soil from a potato field in Ontario with a history of potato scab was about 20,000 CFU/g soil.

Studies on the biology and control of Lachnosterna consanguinea (Blanch.), a pest of sugarcane in Bihar (India)

1961 ◽  
Vol 52 (3) ◽  
pp. 577-587 ◽  
Author(s):  
A. N. Kalea ◽  
J. P. Kulshreshtha
Keyword(s):  
Adverse Effect ◽  
Adult Emergence ◽  
Field Trials ◽  
Bufo Melanostictus ◽  
Grass Roots ◽  
Large Numbers ◽  
Acridotheres Tristis ◽  
Flight Season ◽  
Dry Out ◽  
And Control

The larvae of the Melolonthid beetle, Lachnosterna. consanguinea (Blanch.), have been found to be very destructive to sugarcane in the Dalmianagar area in Bihar, India, since 1956 when they were first recorded there. The pest has since been found to occur in serious numbers in certain adjoining areas and also in Bihta in Patna district. Damage is done by the larvae by feeding on cane roots. Heavily infested cane clumps dry out completely and in severe infestations as much as 80 per cent, of the crop is lost. The infestation occurs only on light sandy soils; crops on clay soils are not affected. The February-planted crop suffers more seriously than that planted in October. The adults have not so far been observed doing any damage to sugarcane.The emergence of adults starts in the last week of April, but a rush of emergence occurs only after the first shower of rain. The adults are nocturnal in habit and feed on leaves of certain bushes and trees during the night. They hide themselves in loose moist soil in day-time. Mating takes place after dusk during the flight season, and eggs are laid in the soil at a depth of 5 to 10 cm. The incubation period varies from 8 to 10 days. The young larvae move to cane roots after some initial feeding on grass roots. They are fully grown in 8 to 10 weeks' time when they move deeper into the soil and pupate in earthen cells at a depth of 0·3 to 1·5 m. The pupal period varies from 12 to 16 days and the pest overwinters in the adult stage. There is only one brood a year.The adults are active at night and are attracted to artificial light and can be destroyed in large numbers with the help of light-traps. Collections from the foliage of trees and shrubs at night is an easier and better method of destruction. Trials with insecticides applied as sprays to the foliage of shrubs in cages to which adults were immediately introduced showed that a suspension containing 0·5 per cent. DDT was effective and was superior to one of BHC.Replicated field trials carried out for the control of the larvae with various insecticides showed that BHG applied to the soil in a dust at the rate of 22·4 Ib. toxicant per acre was the most effective. This treatment, when applied-at planting time (February) had an adverse effect on germination; this effect was not observed when the application was made at the end of May. In subsequent replicated experiments, when BHC in a dust was applied in two instalments at the rate of 10 Ib. per acre at the end of May at the time of the rush of adult emergence, and in July, respectively, much better results were obtained without any adverse effect on the crop. BHC and other insecticides applied to the soil in sprays at 10 Ib. per acre at the end of May were ineffective.Amongst varieties of cane grown at the Bank Farm, Dalmianagar, Co.935 and B.O.3 showed a greater tolerance of injury by the larvae than the others.A Scoliid, Scolia aureipennis Lep., was observed to parasitise the grubs during September. The rate of parasitisation was only about 5 per cent.A disease caused by a fungus, Metarrhizium. anisopliae, was also observed to occur in the adults. Affected beetles died within 4 to 6 days.The common Indian toad (Bufo melanostictus) and the gecko (Gecko gecko) were seen preying on the adults in the evening when these were active. A number of birds, particularly the Indian crow (Corvus splendens) and mynah (Acridotheres tristis), also feed on the larvae when these are exposed during tillage operations.

scholarly journals MSX Sources in the LMC: Dust-Enshrouded AGB Stars, Post-AGB Stars and PN

2003 ◽  
Vol 209 ◽  
pp. 52-52
Author(s):  
P. R. Wood ◽  
M. Cohen
Keyword(s):  
Near Infrared ◽  
Point Sources ◽  
Agb Stars ◽  
Large Numbers ◽  
Red Supergiants ◽  
Selection Of

The Midcourse Space (MSX) Experiment (Price 1995) detected large numbers of point sources in the LMC at 8.28 μm (Egan et al. 2001). Near-infrared J H K L imaging and monitoring of the 504 MSX sources in a region of size 3° x 3.5° covering most of the LMC bar has been carried out. Spectra have been taken for most of the post-AGB stars and a selection of the AGB stars and red supergiants.

scholarly journals Dynamics and Management of Rising Outbreak Spruce Budworm Populations

Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 748 ◽  
Author(s):  
Jacques Régnière ◽  
Barry Cooke ◽  
Ariane Béchard ◽  
Alain Dupont ◽  
Pierre Therrien
Keyword(s):  
Population Growth ◽  
Density Dependence ◽  
Natural Enemies ◽  
Choristoneura Fumiferana ◽  
Regional Scale ◽  
Adult Emergence ◽  
Spruce Budworm ◽  
Migration Activity ◽  
Larval Stages ◽  
The Impact

Management of spruce budworm, Choristoneura fumiferana (Clem.), outbreak spread requires understanding the demographic processes occurring in low, but rising populations. For the first time, detailed observations were made in the early stages of outbreak development. We sampled populations over a three-year period in both treated and untreated populations in the Lower St-Lawrence region of Quebec, Canada, and measured the density-dependence of survival and population growth rates, and the impact of natural enemies and insecticides. Insecticides tested were Bacillus thuringiensis (Berliner 1915) and tebufenozide. We recorded strong density-dependence of survival between early larval stages and adult emergence, explained largely by the variation of natural enemy impacts and overcrowding. We also observed inverse density-dependence of apparent fecundity: net immigration into lower-density populations and net emigration from the higher, linked to a threshold of ~25% defoliation. Because of high migration rates, none of the 2013 treatments reduced egg populations at the end of summer. However lower migration activity in 2014 allowed population growth to be reduced in treated plots. This evidence lends support to the conclusion that, for a budworm population to increase to outbreak density, it must be elevated via external perturbations, such as immigration, above a threshold density of ~4 larvae per branch tip (L4). Once a population has increased beyond this threshold, it can continue growing and itself become a source of further spread by moth migration. These findings imply that populations can be brought down by insecticide applications to a density where mortality from natural enemies can keep the reduced population in check, barring subsequent immigration. While we recognize that other factors may occasionally cause a population to exceed the Allee threshold and reach outbreak level, the preponderance of immigration implies that if all potential sources of significant numbers of moths are reduced on a regional scale by insecticide applications, a widespread outbreak can be prevented, stopped or slowed down by reducing the supply of migrating moths.

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