Mermithid parasites of the mosquito Aedes vexans Meigen in British Columbia

1968 ◽  
Vol 46 (5) ◽  
pp. 1077-1079 ◽  
Author(s):  
Milan Trpiš ◽  
W. O. Haufe ◽  
J. A. Shemanchuk

Newly emerged and apparently healthy female adults of Aedes vexans Meigen were collected in the Fraser Valley, British Columbia, After they had fed once on man at the time of collection and daily on guinea pigs thereafter in the laboratory, they were found to be infected with mermithid worms that developed rapidly at 25 °C. The parasites suppressed ovarian development and caused nearly 100% mortality within 10 days. They started to leave morbid hosts within 7 days. More detailed studies of the life cycle of the mermithid parasites are needed to assess their effectiveness and specificity in the biological control of A. vexans.

2006 ◽  
Vol 138 (4) ◽  
pp. 590-593 ◽  
Author(s):  
David R. Gillespie ◽  
D.M.J. Quiring

AbstractPopulations of Orius spp. were surveyed in the lower Fraser Valley, British Columbia, to determine whether O. insidiosus Say, a non-indigenous species, had established in the region as a result of being released inside greenhouses for biological control of pests. Field collections over 8 years revealed a low incidence of O. insidiosus (10 specimens, <1% of total Orius spp. collected). Numbers in collections did not increase, and collection localities did not become more widespread over the 8 years of survey. Competitive exclusion and temperature and diapause thresholds are discussed as possible mechanisms limiting the establishment of this otherwise widespread North American species.


1994 ◽  
Vol 45 (3) ◽  
pp. 233-237
Author(s):  
Shogo MASUDA ◽  
Hiroko JITSUKAWA ◽  
Keiko SEKI ◽  
Junji SAKURADA ◽  
Miyo MURAI ◽  
...  

1936 ◽  
Vol 14c (8) ◽  
pp. 306-317 ◽  
Author(s):  
G. H. Berkeley

The investigations reported here are concerned with isolations from diseased raspberry roots, preliminary inoculations with isolates, and microscopic examination of naturally and artificially infected roots.The following fungi were isolated from naturally infected roots: Coniothyrium Fuckelii, Cylindrocarpon radicicola, Fusarium sp., possibly F. orthoceras, Cylindrocladium sp., Pythium spp., Rhizoctonia Solani, Rhizoctonia sp. (orchid type), and in preliminary inoculation experiments each fungus was found to be capable of producing necrotic lesions on healthy roots. Microscopic examinations of roots artificially inoculated with pure cultures of the above fungi, showed in the roots the presence of the fungus used for inoculation. In addition the "phycomycetous mycorrhizal" fungus already associated with root rot of strawberries and tobacco was observed to be almost always present in roots of affected raspberry plants, and, to a lesser extent, in apparently healthy roots from apparently normal plants. Nematodes, especially Anguillulina pratensis, the meadow nematode, were present in and on roots from certain soils, while they were absent from roots from other soils. Strawberry and raspberry seeds were sown in sterilized and non-sterilized affected soil with the result that the roots in sterilized soil appeared to be healthy, while those in the non-sterilized soil became affected with necrotic lesions.Evidence is given which shows not only that certain symptoms of raspberry root rot are similar to the symptoms of strawberry root rot, which is considered to be a major factor in the degeneration of strawberries in both Europe and America, but also that many of the fungi and nematodes generally conceded to be associated with root rots of strawberry are likewise associated with root rots of raspberry. In the Fraser Valley, British Columbia, where certain raspberry plantations appear to be heavily infected with root rots, the possibility that these root rots may play an important role in connection with the un-thriftiness of such plantations should not be overlooked.


2004 ◽  
Vol 64 (2) ◽  
pp. 237-242 ◽  
Author(s):  
M. C. Lacerda ◽  
A. M. R. M. Ferreira ◽  
T. V. Zanuncio ◽  
J. C. Zanuncio ◽  
A. S. Bernardino ◽  
...  

Biological control has been reducing the use of chemical products against insect pests, specially predatory Pentatomidae. Species of this group can present high variations in their life cycle as a result of their diet. Thus, the objective of this research was to study nymph development and reproduction of Podisus distinctus (Stäl, 1860) (Heteroptera: Pentatomidae) fed on Bombyx mori L., 1758 (Lepidoptera: Bombycidae) larvae (T1), compared to those fed on Tenebrio molitor L., 1758 (Coleoptera: Tenebrionidae) (T2) and Musca domestica L., 1758 (Diptera: Muscidae) larvae (T3) at a temperature of 25 ± 0.5ºC, relative humidity of 70 ± 2%, and photophase of 12 h. Predators fed on B. mori showed duration of the nymph phase (18.68 ± 1.02) similar to those fed on T. molitor (18.32 ± 1.49). Pre-oviposition and oviposition periods and number of egg masses, besides eggs and nymphs per female, were higher with B. mori (5.83 ± 2.02; 15.00 ± 7.40; 8.42 ± 1.84; 296.69 ± 154.75; and 228.55 ± 141.04, respectively) while longevity of males and females of P. distinctus was 25.76 ± 16.15 and 35.00 ± 16.15 days with T. molitor, and 20.57 ± 13.60 and 23.46 ± 12.35 days with B. mori, respectively.


1993 ◽  
Vol 71 (3) ◽  
pp. 519-521 ◽  
Author(s):  
B. J. van der Kamp

Records of uredinia and telia production on the alternate hosts of Cronartium coleosporioides in British Columbia and inoculation of Castilleja miniata with aeciospores collected from various locations showed that rust isolates from dry areas of the interior of British Columbia do not produce uredinia and may have lost the ability to do so. Collections from somewhat wetter areas produced uredinia or mixtures of uredinia and telia immediately following aeciospore inoculations, and field collections from such areas in June commonly had mixtures of uredinia and telia. Loss of the uredinial stage may be a response to climates that are often unsuitable for the spread or survival of the rust on the alternate host. Key words: stalactiform rust, uredinia, telia, rust life cycle.


1967 ◽  
Vol 99 (4) ◽  
pp. 411-418 ◽  
Author(s):  
John W. E. Harris ◽  
Harry C. Coppel

AbstractA study was made of the poplar-and-willow borer, Sternochetus (= Cryptorhynchus) lapathi (L.) (Coleoptera: Curculionidae), in British Columbia between 1959 and 1964. The borer occurred principally south of 52 degrees north latitude. Willows were the preferred hosts. Ornamentals, hybrids in commercial plantings, and natural growing trees were attacked. The life cycle of the insect on southern Vancouver Island lasted up to 3 years; overwintering took place in early instar and adult stages. Eggs were laid in the bark; larvae mined first in the bark and then in the wood, where pupation took place. Few parasites and predators were found. DDT, dieldrin, and BHC killed adults; lindane (0.5% water emulsion), applied in the spring, caused larval mortality up to 96%.


1964 ◽  
Vol 54 (4) ◽  
pp. 797-803 ◽  
Author(s):  
Jean M. Taylor

A description is given of the life-cycle in Britain of Theocolax formiciformis Westw. (Pteromalidae), a parasite of Anobium punctatum (Deg.) (Anobiidae). Adults emerge from infested wood in large numbers from April to June. Eggs are laid through the wood surface and use was made of this habit as a means of rearing this parasite under observation in the laboratory. Anobium larvae were placed individually in channels gouged in the surface of 3-inch squares of plywood. They were covered with tracing paper and the parasites were caged on this by means of a glass ring covered with a glass plate. Development from egg to adult at 22 and 25°C., and 75 per cent, relative humidity, averaged about five and six weeks, respectively, compared with 12 weeks outdoors in summer. The number of progeny per female was highest (approximately five) at 22°C., at which the ratio of males to females was 1:3. Only about one per cent, of the adults reared were winged. The use of Theocolax as a biological-control agent is not considered practical.


2021 ◽  
Vol 13 (10) ◽  
pp. 96
Author(s):  
Eduardo Carvalho Faca ◽  
Fabrício Fagundes Pereira ◽  
Winnie Cezario Fernandes ◽  
Ivana Fernandes da Silva ◽  
Valmir Antônio Costa ◽  
...  

The study of the interaction between parasitoid and host, especially the age of these organisms, is an important step towards the implementation of biological control programs. Therefore, we investigated the performance of Ooencyrtus submetallicus (Hymenoptera: Encyrtidae) and Trissolcus sp. aff. urichi (Hymenoptera: Scelionidae) parasitizing eggs of Nezara viridula (Hemiptera: Pentatomidae), considering different ages of the parasitoids and the host. We performed four laboratory bioassays: two using females of O. submetallicus and Trissolcus sp. aff. urichi at 24, 48, 72, 96, 120, or 144 hours of age exposed to parasitism in N. viridula eggs (24 h) and two trials with N. viridula eggs at 24, 48, 72, 96, 120, or 144 hours exposed to the parasitism of O. submetallicus and Trissolcus sp. aff. urichi (24 h). We evaluated the percentage of parasitism and emergence, life cycle length, progeny, sex ratio, and the longevity of the parasitoids. The parasitism of O. submetallicus in N. viridula eggs was influenced by the age of the parasitoid, 120 hours being the minimum to obtain better parasitism. From this age on, there is interference in the longevity of the progeny. Trisolcus sp. aff. urichi, at all ages, parasitized N. viridula eggs relatively well, but with almost no emergence of the parasitized eggs. Females of O. submetallicus parasitized and developed in eggs of N. viridula of all ages. Females of Trissolcus sp. aff. urichi parasitized their host, but there was barely any emergence. These pieces of information regarding the breeding methodology contribute to the implementation of new protocols for the multiplication of these parasitoids in the laboratory, and later, their release in the field.


Plant Disease ◽  
2013 ◽  
Vol 97 (4) ◽  
pp. 559-559 ◽  
Author(s):  
J. F. Elmhirst ◽  
B. E. Auxier ◽  
L. A. Wegener

Boxwoods (Buxus spp.) are common woody ornamental hedging plants in Europe and North America, typically propagated by cuttings. In October 2011, shoot dieback and defoliation was observed on Buxus sempervirens ‘Suffruticosa’ (dwarf English boxwood) and ‘Green Balloon’ in outdoor, 10-cm pots at a wholesale nursery in Chilliwack, British Columbia. Circular leaf spots with black rings occurred on leaves and black, water-soaked, cankers girdled the stems and petioles. Leaf and stem samples were collected on November 21, 2011, and incubated for 48 h in a moist chamber at room temperature. In addition to Volutella buxi, a Cylindrocladium species producing conidia on white sporodochia was observed on host tissue under the microscope. Leaves with lesions were surface-sterilized in 10% bleach for 30 to 60 s, rinsed in sterile water, and lesions were cut out and plated on PDA and carnation leaf media. The species was identified as Cylindrocladium pseudonaviculatum Crous, J.Z. Groenew. & C.F. Hill 2002 by comparison of conidia and phialide morphology to published descriptions. Conidia were hyaline, one-septate, cylindrical with rounded ends and 38 to 76 μm (mean 51 μm) × 4 to 6 μm on carnation leaf media and 41 to 66 μm (mean 52 μm) × 4 to 6 μm on B. sempervirens ‘Suffruticosa’ leaves, comparable to the reported range of 40 to 75 × 4 to 6 μm (1,2,3,4). Conidia were produced in clusters on terminal, ellipsoid vesicles at the tips of penicillate conidiophores. Vesicles were 10.2 (7.6 to 12.8 μm) at the widest point, consistent with the 6 to 11 μm reported in (2,3) and tapered to a rounded point; stipe extensions were septate and measured an average of 130 μm (107 to 163 μm) in length to the tip of the vesicle, consistent with the 95 to 155 μm reported in (1), 89 to 170 μm reported in (2), and 95 to 165 μm in (3). Chlamydospores were not observed on host tissue but appeared in older PDA cultures as dark brown microsclerotia. DNA was extracted from single-spore colonies on PDA and the internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS1 and ITS4. The ITS sequence (GenBank Accession No. KC291613) was 100% identical to C. buxicola strain CB-KR001 (HM749646.1) and Calonectria pseudonaviculata strain ATCC MYA-4891 (JX174050.1). In early December 2011, box blight was identified on container-grown B. sinica var. insularis × B. sempervirens ‘Green Velvet,’ ‘Green Gem’, and ‘Green Mountain’ and B. sempervirens L. (common or American boxwood). The pathogen was identified by microscopic examination at three wholesale nurseries in the eastern Fraser Valley and one landscape planting. The isolate has been deposited in the Canadian Collection of Fungal Cultures in Ottawa, Canada (DAOM 242242). References: (1) B. Henricot and A. Culham. Mycologia 94:980, 2002. (2) K. L. Ivors, et al. Plant Dis. 96:1070, 2012. (3) C. Pintos Varela, et al. Plant Dis. 93:670, 2009. (4) M. Saracchi, et al. J. Plant Pathol. 90:581, 2008.


Sign in / Sign up

Export Citation Format

Share Document