A Virus Disease of Swaine's Jack Pine Sawfly, Neodiprion swainei Midd. Sprayed from an Aircraft

Neodiprion swainei Middleton is the most serious defoliator of jack pine, Pinus bamksiana Lambert, in Canada. The damage to stands of this species in northern Quebec has been extensive and has resulted in considerable forest-fire hazard. Virus infected sawflies were found in the Lac Gagnon area in Quebec in 1956, and a study of the disease was begun by the Quebec Laboratory in 1957. Laboratory propagation methods were developed and resulted in the production of a quantity of polyhedral concentrate of a virulent strain. Concentrations of polyhedral bodies needed in a spray formulation to infect and kill larvae of various ages were determined in the laboratory and field tests demonstrated the potentialities of this disease as a biological control agent (Smirnoff 1960b, 1961a). These studies served as a basis for the experiment in the dissemination of the disease by aircraft described in this paper.

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Behavior of a Wild-Type and Two Mutant Strains of Colletotrichum gloeosporioides f. sp. aeschynomene on Northern Jointvetch in the Field

Plant Disease ◽

10.1094/pdis.1998.82.4.374 ◽

1998 ◽

Vol 82 (4) ◽

pp. 374-379 ◽

Cited By ~ 4

Author(s):

Y. Luo ◽

D. O. TeBeest

Keyword(s):

Population Density ◽

Wild Type Strain ◽

Colletotrichum Gloeosporioides ◽

Biological Control Agent ◽

Field Tests ◽

The United States ◽

Control Agent ◽

Sampling Time ◽

Wild Type ◽

Mutant Strains

The fungus Colletotrichum gloeosporioides f. sp. aeschynomene causes an anthracnose on Aeschynomene virginica and has been used as a biological control agent to control this weed in the United States. The population dynamics of a wild-type strain (3-1-3) and two mutant strains of 3-1-3 of C. gloeosporioides f. sp. aeschynomene, a benomyl-resistant strain (B21) and nitrate-nonutilizing strain (Nit A), were studied in field tests on northern jointvetch in 1994 and 1995 to determine how the strains interacted on infected plants under field conditions. Plants were co-inoculated with strains 3-1-3 and B21, strains 3-1-3 and Nit A, and strains 3-1-3, B21, and Nit A at equal and unequal initial proportions. Plants were grown and maintained under flooded conditions in small wading pools. In co-inoculation of plants with 3-1-3 and B21 from equal initial proportions, the population of 3-1-3 increased slightly until it reached a proportion of 60 to 70%, whereas the population density of B21 reached 30 to 40% at the end of growing season. From unequal initial proportions, the population density of B21 decreased from 90 to about 50%, whereas the 3-1-3 increased from 10 to 50%. The population density of 3-1-3 increased from an equal initial proportion and was significantly greater than that of Nit A on every sampling time. From unequal initial proportions, the population density of 3-1-3 increased from 10 to 90%, whereas that of Nit A declined. In co-inoculation of plants with the three strains, the population density of 3-1-3 was significantly greater than those of the mutant strains at every sampling time. The proportions of mutant strains within the total population of C. gloeosporioides f. sp. aeschynomene on plants varied according to the test conditions and the number and types of strains co-inoculated.

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A simple method for the detection of Leptolegnia chapmanii from infected Aedes aegypti larvae

Canadian Journal of Microbiology ◽

10.1139/cjm-2012-0703 ◽

2013 ◽

Vol 59 (6) ◽

pp. 425-429 ◽

Cited By ~ 5

Author(s):

Renan N. Leles ◽

Cláudia C. López Lastra ◽

Juan J. García ◽

Éverton K.K. Fernandes ◽

Christian Luz

Keyword(s):

Aedes Aegypti ◽

Biological Control Agent ◽

Field Tests ◽

Water Film ◽

Control Agent ◽

Significant Progress ◽

Simple Method ◽

Large Numbers ◽

Simplified Method ◽

Leptolegnia Chapmanii

Significant progress in developing Leptolegnia chapmanii as a biological control agent against mosquitoes will be accelerated by improved and simpler methods to detect and to isolate this virulent and rapidly lethal watermold from field-collected mosquito larvae. To date, however, this oomycete has remained understudied and little used. This study presents a simplified method to detect Leptolegnia in infected Aedes aegypti larvae. The development of L. chapmanii inside mosquitoes is easily monitored when pathogen-treated larvae are quasi-immobilized for an initial 48 h in the water film on plates of water agar amended with antibiotic (chloramphenicol, 0.5–1 g/L) and fungicide (thiabendazole, 4–8 g/L) and then transferred to a larger volume of water for an additional 48 h. Surprisingly, chloramphenicol stimulated oosporogenesis by L. chapmanii. The method permits processing of large numbers of A. aegypti and other culicid larvae and is useful for both obtaining new strains and also monitoring the efficacy of L. chapmanii during field tests.

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Studies on the biology of Aphidius sonchi Marshall (Hymenoptera: Aphidiidae), a parasite of the sowthistle aphid, Hyperomyzus lactucae (L.) (Hemiptera: Aphididae)

Bulletin of Entomological Research ◽

10.1017/s0007485300014280 ◽

1985 ◽

Vol 75 (2) ◽

pp. 199-208 ◽

Cited By ~ 7

Author(s):

Liu Shu-Sheng ◽

Mary Carver

Keyword(s):

Adult Stage ◽

Virus Disease ◽

Biological Control Agent ◽

Adult Life ◽

Control Agent ◽

Macrosiphum Euphorbiae ◽

Principal Vector ◽

Adult Females ◽

Hymenopterous Parasite ◽

Males And Females

AbstractThe hymenopterous parasite, Aphidius sonchi Marshall, has been introduced into Australia as a biological control agent of the sowthistle aphid, Hyperomyzus lactucae (L.), the principal vector of lettuce necrotic yellows virus disease. Some aspects of its biology were studied in the laboratory. Females reared at 22°C contained a mean ± s.e. of 179·4 ± 10·26 eggs on emergence, and more eggs were formed during adult life. Unmated females produced male progeny only; mated females produced progeny of both sexes. At 22°C, both males and females mated within 12 h of emergence. Virgin females could mate successfully after having commenced oviposition and switch to producing progeny of both sexes. At 20°C, both virgin and mated females started oviposition within 7 h of emergence. The female oviposited in all nymphal instars and both apterous and alate adults of the host. Only one egg was laid per insertion of the ovipositor. Superparasitization was common, but only one parasite per aphid survived to the adult stage. Females at 22°C and LD 12:12 oviposited during both the photophase and the scotophase; the proportion of eggs laid in the scotophase was correlated with the availability of hosts. Adult females lived longer in the absence of hosts than in their presence and lived longer than males, and those supplied with water and honey lived longer than those without. Facultative diapause occurred. The integumental coloration of adults varied according to the temperature during their immature stages. Females of A. sonchi oviposited readily in Macrosiphum euphorbiae (Thomas), but their progeny did not develop beyond the egg stage. A. sonchi was parasitized by Alloxysta ancylocera (Cameron), Pachyneuron aphidis (Bouché) and Dendrocerus carpenteri (Curtis) in the field.

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Morpho-taxometrical and molecular characterization of Steinernema abbasi (Nematoda: Steinernematidae) and its pathogenicity and generative potential against lepidopteran pests

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-020-00359-1 ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Heena ◽

Aasha Rana ◽

Aashaq Hussain Bhat ◽

Ashok Kumar Chaubey

Keyword(s):

Galleria Mellonella ◽

Insect Pests ◽

Biological Control Agent ◽

Virulent Strain ◽

Entomopathogenic Nematode ◽

Uttar Pradesh ◽

Original Description ◽

Control Agent ◽

Lepidopteran Insect ◽

Highly Virulent

Abstract Background An entomopathogenic nematode (EPN) was recovered by using Galleria baiting technique from the soils of marigold fields of Noida, Uttar Pradesh, India. Based on morphological, morphometrical and molecular characterizations, the isolated strain was identified as Steinernema abbasi and tagged as CS38. The isolated strain was conspecific to original description with minor deviations. Infective juveniles (IJs) of present strain were longer than original description. Results Molecular analysis was done using ITS1-5.8S-ITS2 and D2D3 regions. Pathogenicity and generative potential of the present strain CS38 were tested against larvae of 3 lepidopteran insect pests, namely, Galleria mellonella L., Helicoverpa armigera (Hb.) and Spodoptera litura (Fab.). Different concentrations of IJs/larva, viz. 25, 50, 100, and 200 IJs/larva, were used for bioassay trails. All experiments were repeated thrice to reach the optimum authenticity. Results of bioassays revealed that isolate CS38 was highly virulent against the 3 insect pests and caused (100%) mortality within 48 h under laboratory conditions. Generative potential of the studied S. abbasi CS38 was recorded high in G. mellonella (19 × 104 IJs/larva) at 100 IJs/larva concentration, followed by H. armigera (63.4 × 103 IJs/larva) and S. litura (60.5 × 103 IJs/larva). Conclusions Isolate CS38 is an indigenous, dominant and highly virulent strain that can be utilized as a biological control agent against the three studied insects. Moreover, it can be used for commercialization of the production of EPN-based biopesticide to be added under Integrated Pest Management in Indian agriculture system.

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