当前位置： SCI文献检索 > APPLIED AND ENVIRONMENTAL MICROBIOLOGY期刊下所有文献 > Microbial Ecology of the Gut in Laboratory Stocks of the Migratory Grasshopper, Melanoplus sanguinipes (Fab.) (Orthoptera: Acrididae).

Microbial Ecology of the Gut in Laboratory Stocks of the Migratory Grasshopper, Melanoplus sanguinipes (Fab.) (Orthoptera: Acrididae).

Abstract：

:Mean pH values in pooled samples of foregut, midgut, and hindgut from adult Melanoplus sanguinipes, which had been raised in the laboratory on barley shoots and wheat bran, were 5.15, 6.39, and 5.98, respectively. Homogenates of midgut/hindgut sections and frass (feces) yielded colony counts of bacteria by the spread plate method of 5.7 to 5.9 and 5.3 to 5.5 log(10) colonies per mg, respectively; there were no significant differences (P > 0.05) between counts obtained on several media or on media incubated aerobically or anaerobically. There was no evidence of significant populations of protozoa, fungi, or obligately anaerobic bacteria associated with the gut. A total of 168 pure strains of bacteria isolated from the gut sections were characterized and assigned to 11 taxonomic groups, including Enterococcus spp., Serratia liquefaciens, Pseudomonas spp., and Enterobacter spp. Numbers of Enterococcus spp. in the gut were 2 to 3 orders of magnitude higher than those of the other genera. Strains representing only four of the groups were recovered from bran fed to the grasshoppers; the barley shoots, which were raised in sterile soil, appeared virtually sterile. Examination of the gut wall by scanning electron microscopy revealed the presence of epimural bacteria in the foregut and hindgut but not in the midgut. The distribution of epimural cocci and bacilli differed with the gut section examined. Numerous spherical to ovoid structures up to 10 mum in diameter, which were not identified, were associated with the microvillous surface of the midgut epithelium. Acetate was present in gut, hemolymph, and frass, and it was shown that representative isolates of Enterococcus spp. and Enterobacter agglomerans produced acetate when incubated in an aqueous suspension of bran. The egestion time of solid digesta, as measured with methylene blue-stained barley shoots, was 3.0 to 5.7 h. The results show that M. sanguinipes supported extensive indigenous populations of luminal and epimural bacteria in the gut which were composed predominantly of facultatively anaerobic species; the relatively short egestion time, indicating rapid passage of digesta through the gut, was consistent with the microscopic appearance of digesta residues in frass and could account, at least in part, for the absence of a significant population of obligately anaerobic bacteria from the gut.

journal_name

Appl Environ Microbiol

journal_title

Applied and environmental microbiology

authors

Mead LJ,Khachatourians GG,Jones GA

doi

10.1128/AEM.54.5.1174-1181.1988

keywords:

subject

Has Abstract

pub_date

1988-05-01 00:00:00

pages

1174-81

issue

eissn

0099-2240

issn

1098-5336

journal_volume

pub_type

杂志文章

在线工具

Microbial Ecology of the Gut in Laboratory Stocks of the Migratory Grasshopper, Melanoplus sanguinipes (Fab.) (Orthoptera: Acrididae).