The spruce budworm (Choristoneura fumiferana) is the most economically important indigenous pest in eastern North America. In order to protect valuable timber the budworm population must be restricted to endemic levels. To achieve this, and simultaneously attempt to improve environmental quality is a major objective of much research into the development of new insect control methods. This review presents an encapsulated report of researches into the use of pheromones and hormones (autocides), and viruses, fungi, bacteria and microsporida (microorganisms) as possible control agents. Such agents would be more selective than conventional insecticides. Several of the control methods discussed in this report are almost operational, and while it is evident that none of them can completely replace chemical insecticides, field tests indicate that they have a potential in budworm control. The results also indicate the urgent need for testing the integrated use of the autocides and microorganisms, and the integrated application of these newer control agents with conventional chemical insecticides.

Oxygen uptake was determined by manometric methods on the microorganisms in a greenhouse potting soil, a bacterial isolate from this soil, and a bacterial isolate from a peach orchard soil, using as carbon sources the systemic fungicide Benlate (Fungicide 1991, 50 percent wettable powder active ingredient) and the active component benomyl (reagent grade methyl l-(butylcarbamoyl)-2-benzimidazolecarbamate). Uptake by the microorganisms in the greenhouse potting soil was higher in systems containing Benlate than in those without the fungicide. A bacterial isolate (Achromobacter sp.) from the greenhouse potting soil, showed higher trends in oxygen uptake with autoclaved soil plus Benlate than in soil with benomyl added at the same concentration. Oxygen uptake by a bacterial isolate from a peach orchard soil (Achromobacter sp.) was significantly higher in a system with benomyl, inorganic salts, and glucose than in the same system with Benlate, suggesting an additive effect by benomyl. Results with the bacterial isolate from the peach orchard soil where the fungicide and benomyl were added at the 16-hr time indicated that Benlate and benomyl were inhibitory to oxygen uptake once respiration had begun.

"Feeding forages high in nitrates to dairy animals can cause a problem called nitrate toxicity. Ruminants have the ability to utilize some nitrate from the diet through the bacteria in the rumen. But when the capacity of the rumen microorganisms to break down and utilize nitrates is exceeded, nitrate accumulation and poisoning occurs"-- Page 1.

Measurements of fallout of particles and microorganisms were carried out during the light and dark period in animal rooms occupied by rats, rabbits, cats and monkeys. Correlations between both parameters were established. The 24-hour mean was calculated and the percentage deviation of the individual measurements from this mean used for the elaboration of phase maps. For rats there is a high increase of particle and microorganism emission during the night following the activity cycle, while for cats and monkeys emission increases only during the feeding period. In rabbit rooms there is a nearly equal emission during day and night.

A field study of a 65-hectare area and a laboratory study of samples from two Boroll profiles and two Boralf profiles was conducted to determine why these extensive forested Borolls at high elevation have such an unusually high organic matter content. The study revealed that in these Rendzina-like Borolls, organic litter decomposes much more slowly than in an adjoining Boralf, as indicated by differences in organic matter contents. This difference in rate of microbial oxidation does not depend primarily on nutrients supplied to the microorganisms or on invasion by locally indigenous microflora. Slow decomposition of Boroll organic matter probably results from protection afforded by its mixture with mineral soil in the gut of terrestrial snails (Ashmunella rhyssa).

Tropical and temperate grasses were investigated for the amounts and the relative ease of degradation of tis. sue types in leaf blades to relate microanatomy to digestibility. Leaf blades of five tropical and six temperate grasses, grown in different locations but harvested at four weeks of summer regrowth, were examined by light microscopy for cross sectional percentages of total vascular tissue, lignified vascular tissue, phloem, epidermis, sclerenchyma, and mesophyll. Leaf blades of four of the tropical grasses and the six temperate species were evaluated for in vitro degradation of tissue types by tureen microorganisms using scanning electron microscopy. Bermudagrasses, Cynodon dactylon (L.) Pers. possessed about 36% total vascular tissue with 27% of the leaf blade section composed of parenchymal bundle sheaths; totals of vascular tissue for the other grasses were lower, ranging from 11.0% to 22.1%. The parenchymal bundle sheaths, which occupied > 50% of the area for total vascular tissue in tropical grasses but < 50% in all temperate species, were more rigid and usually digested at a slower rate in the tropical grasses. In all grasses, mesophyll and phloem were degraded before the other tissues but were degraded more rapidly in the temperate species. Leaf blades of tropical grasses had an average of 22 percentage units less of the easily digested tissue (mesophyll and phloem) and 25 percentage units more of the slowly digested tissues (epidermis and parenchymal bundle sheath) than temperate species. Except for the bermudagrasses, the percentages of lignified tissue were higher in temperate species. Differences in the ease of degradation were apparent between similar tissues of different grass types, species, and cultivars. Results indicated that leaf blade microanatomy and inherent characteristics of cell walls affect digestibility by rumen microorganisms.