| electrophoretic characterization of chromosomal dna from two microsporidia. | spores of two microsporidia, nosema pyrausta (from the european corn borer, ostrinia nubilalis) and n. furnacalis (from the asian corn borer, o. furnacalis) were harvested from laboratory-reared o. nubilalis caterpillars and purified by centrifugation through percoll. conditions permitting in vitro germination were defined for both species and found to be different. n. pyrausta spores were incubated in 0.1 n koh for 30 min, recovered by centrifugation, and resuspended in 1 ml of an equal mixture ... | 1990 | 2125628 |
| quantitative assessment of biotic mortality factors of the european corn borer (lepidoptera: crambidae) in field corn. | five treatments were used to exclude naturally occurring predators and parasitoids, based on body size and flight ability, to assess their effect on ostrinia nubilalis (hübner) populations on corn plaits. two initial o. nubilalis egg densities (one egg mass and three egg masses per plant) were assigned to each treatment. egg predation was higher in uncaged treatments than in caged treatments. flying insect predators, primarily coleomegilla maculata degeer (coleoptera: coccinellidae), reduced egg ... | 2001 | 11425014 |
| interactions between nosema pyrausta (microsporidia: nosematidae) and bacillus thuringiensis subsp. kurstaki in the european corn borer (lepidoptera: pyralidae). | larval susceptibility to bacillus thuringiensis was determined for nosema pyrausta-infected and uninfected european corn borers, ostrinia nubilalis (hübner), in bioassays using a commercial formulation of b. thuringiensis subsp. kurstaki, dipel es, incorporated into diet. lc50 values for n. pyrausta-infected larvae were significantly lower (p<0.0001) than for uninfected larvae and declined with increasing levels of infection. lc50 values for a 15-d bioassay using field-colony first instars were ... | 2001 | 11777037 |
| interaction of nosema pyrausta and temperature on ostrinia nubilalis egg production and hatch. | nosema pyrausta is an obligate pathogen causing reduced fecundity and longevity of ostrinia nubilalis. this study was conducted to determine the combined effects of n. pyrausta infection and temperature on o. nubilalis egg production and hatch. n. pyrausta-infected and noninfected o. nubilalis were maintained in two different temperature regimes. the first regime allowed females to oviposit under optimum conditions (27 degrees c, 65% rh, 16:8 (l:d)), while females in the second regime were held ... | 2001 | 12009801 |
| growth, development, and survival of nosema pyrausta-infected european corn borers (lepidoptera: crambidae) reared on meridic diet and cry1ab. | transgenic corn, zea mays l., hybrids expressing crystal protein endotoxin genes from bacillus thuringiensis berliner are an increasingly popular tactic for managing the european corn borer, ostrinia nubilalis (hübner), in north america. o. nubilalis populations also are often vulnerable to the ubiquitous entomopathogenic microsporidium nosema pyrausta (paillot). we examined the effect of feeding meridic diet incorporated with purified cry1ab on growth, development, and survival of nosema-infect ... | 2004 | 15384327 |
| physiological host specificity: a model using the european corn borer, ostrinia nubilalis (hübner) (lepidoptera: crambidae) and microsporidia of row crop and other stalk-boring hosts. | we investigated vertical and horizontal transmission as means by which entomopathogenic microsporidia may be isolated in their hosts. ostrinia nubilalis larvae were challenged with microsporidia isolated from other stalk-boring and row crop lepidoptera and were susceptible to seven species. two species were horizontally transmitted. a nosema sp. from eoreuma loftini was transmitted among o. nubilalis larvae but not among larvae of the e. loftini host. this species was also vertically transmitted ... | 2005 | 16214162 |
| effects of infection with nosema pyrausta on survival and development of offspring of laboratory selected bt-resistant and bt-susceptible european corn borers. | infection with nosema pyrausta paillot lengthens developmental period of bt-susceptible ostrinia nubilalis (hübner) to a similar extent as feeding on cry1ab-incorporated diet in cry1ab-resistant o. nubilalis, and these two factors combined lengthen developmental period further than either alone. resistant o. nubilalis mating with infected susceptible, or infected resistant partners would produce partially- and fully-resistant offspring, respectively, infected with n. pyrausta. to investigate the ... | 2010 | 20673768 |
| [incidence of microsporidian infection of stem borers of the genus ostrinia (lepidoptera: crambidae) in the krasnodar territory]. | infection of corn borers of the genus ostrinia with microsporidia is found for the first time in russia. incidence rates of the last instar larvae of the second generation, sampled under natural conditions in the krasnodar territory, is ranged between 3.0 and 17.2%. when infection incidence rates have been compared between larvae, collected (a) on the western and eastern borders of the region and (b) on dicotyledonous (cocklebur, mugwort) and monocotyledonous plants (maize), no distinct differen ... | 2011 | 21874854 |
| lyophilization, vacuum drying, and subsequent storage of nosema pyrausta spores. | | 2014 | 4213234 |
| redefinition of nosema pyrausta (perezia pyraustae paillot 1927) basing upon ultrastructural and molecular phylogenetic studies. | populations of european corn borer (ostrinia nubilalis hübner) from krasnodar territory (southwestern russia) become regularly infected with nosema-like microsporidia. to identify the parasite, it was subjected to electron microscopy and small subunit ribosomal rna (ssu rrna) gene sequencing. the spore ultrastructure of the parasite was highly similar to nosema bombycis from china and nosema pyrausta from the usa. the nucleotide sequence of ssu rrna gene was identical to a microsporidium isolate ... | 2015 | 25563606 |
| putting the brakes on a cycle: bottom-up effects damp cycle amplitude. | pest population density oscillations have a profound effect on agroecosystem functioning, particularly when pests cycle with epidemic persistence. here, we ask whether landscape-level manipulations can be used to restrict the cycle amplitude of the european corn borer moth [ostrinia nubilalis (hübner)], an economically important maize pest. we analysed time series from minnesota (1963-2009) and wisconsin (1964-2009) to quantify the extent of regime change in the us corn belt where rates of trans ... | 2012 | 22364256 |