The introduction of microorganisms with specific degradative capacities into the soil was shown to be a possible means of ridding the soil of contaminating chemicals. An investigation of the interactions of soil microorganisms and several groups of herbicidal compounds, primarily chlorinated derivatives, was made. In pure culture and in soils the addition of 2,3,5,6-tetrachloroterephthalate (DCPA) had little effect upon bacterial growth, and several microorganisms appeared to use the herbicide as a carbon source. The encouragement of the soil microflora by the addition of nutrient broths resulted in a reduction of toxicity to plants of a number of herbicides. Isopropyl N-phenylcarbamate (IPC) degrading organisms, when added to soil, accelerated the degradation of IPC and related compounds. A membrane 'biologicalilter' device for reducing waterborne biodegradable pollutants was also demonstrated using these organisms.

Soil samples were incubated in air atmosphere containing 0, 10,000, 50,000, and 500,000 ppm propane gas (Ca₃H₈) by volume. Carbon dioxide evolution was used a measure of soil microbial activity. Soil N immobilization was determined by measuring soil inorganic N. Carbon dioxide evolution and N immobilization were directly related to the Calls concentration. Carbon dioxide evolution over time was characterized by (1) initial delay of 2 to 4 weeks, (2) an accelerated period, and (3) a decrease in activity caused by a shortage of Increasing the C₃H₈ concentration shortened the delay period and accelerated CO₂ evolution and N immobilization. The C₃H₈ was used as a source of energy by microorganisms that immobilized the soil inorganic N. The use of C₃H₈ as an energy source for microorganisms has potential usefulness in studying basic soil microbiological problems relating to soil nutrient transformations because the C₃H₈ itself can be easily removed and does not interfere with subsequent analyses.

Examples of the biological occurrence of methyl ketones are reviewed. The lack of significant accumulations of these compounds in the biosphere indicates that a recycling of these organic molecules is occurring. Evidence for biodegradation of acetone by mammals and longer methyl ketones by microorganisms via terminal methyl-group oxidation is discussed. A new mechanism for the subterminal oxidation of methyl ketones by microorganisms is proposed whereby the first intermediate produced is an acetate ester which subsequently is cleaved to acetate and a primary alcohol two carbons shorter than the original ketone substrate.Methyl ketones can be produced by mammals and fungi by decarboxylation of β-keto acids. Some bacteria are able to form methyl ketones via the oxidation of aliphatic hydrocarbons at the methylene carbon α to the methyl group. Speculations on the biosynthesis of methyl ketones by insects and plants and a discussion of the possible biological roles of methyl ketones in diverse biological systems are presented.

Simple thin-layer chromatographic procedures are outlined for the separation, isolation, and characterization of a complex of lipophilic naphthoquinones. Procedures are also described for the quantitative recovery of naphthoquinones from thin-layer plates. The general usefulness of the described methods is demonstrated by their application in the analysis of menaquinones from several microorganisms. The methods allow distinction between menaquinones varying in side-chain length, degree of saturation, and geometry, as well as in the presence or absence of ring methyl groups.

Chemical properties of microbially bound aggregates were determined by organic solvent extraction and by the rate of sonic dispersion of the aggregates. Seven fungi, six streptomycetes, and four bacteria, produced in situ chemically different binding agents which conferred different chemical and physical properties on soil aggregates. A. tenuis, S. atra, and two species of Penicillium apparently bound soil aggregates by the production of humic-like binding materials. Six streptomycetes and two Aspergillus species obtained their effectiveness by production of a combination of humic-like components and polysaccharides. Components of lignin-like character were involved in the stabilization of aggregates bound by two Aspergillus species. B. polymyxa, R. trifolii, and two species of Agrobacterium bound soil aggregates largely by NaIO₄-oxidizable polysaccharide gums. M. hiemalis was the only organism that bound aggregates by waxy or fatty components. Microorganisms differ widely in their ability to affect mechanical stability of water-stable soil aggregates. The ability of each microorganism to bind mechanically stable aggregates varied between soil types. Aggregates bound by A. tenuis and S. atra, B. polymyxa, and A. radiobacter were more stable than those bound by other microorganisms, as evidenced by the longer exposure time required for sonic dispersion. The aggregates produced by S. purpurascens and S. coelicolor were less resistant to sonic dispersion. Aggregates of three soils bound by A. zonatus and M. hiemalis were destroyed easily by sonication. Microbially-bound Kewaunee clay aggregates were generally the most resistant to sonic dispersion.

Periodic taste and odor at the Cleveland, Ohio Crown Water Treatment Plant prompted investigation of the role microorganisms play in the problem. Fungi, bacteria, and algae collected near the plant intake were studied during June through August 1971. During the three months of sampling, no vertical distribution pattern was noted in quantitative analysis of the phytoplankton. A number of algae, reported to induce taste and odor in water, were identified. Whatever the source of these odors, they were not due to benthic or periphyton algae, but could have been associated with the phytoplankton community as the reported 'Lake Erie odor' coincided with phytoplankton increase.

Establishment of Azotobacter paspali in the rhizosphere of Paspalum notatum grown in sand was consistently successful only with tetraploid varieties of the grass when glucose was added at the time of inoculation. Increases in the nitrogen content of the roots and in the total nitrogen content of the sandplant system were associated with successful Azotobacter colonization. These increases were significant at p < 0.05. There was no evidence for improved growth or for nitrogen gains in the above-ground portions of the plants resulting from A. paspali establishment. Soils containing tetraploid P. notatum and A. paspali showed considerable nitrogen fixation, as measured by acetylene reduction. The nitrogen gains appeared to be a consequence of growth of photosynthetic microorganisms, since all fixation ceased when soils were incubated in the dark.

The orange TORTRIX, Argyrotaenia citrana (Fernald), caused considerable damage to grapes in vineyards near Soledad in the Salinas Valley during 1968 and 1969. This insect is morphologically identical to the “apple skin-worm” which is a pest of several deciduous fruit trees and other plants in several northern California coastal counties. So far, it has not been found on grapes in Napa, Sonoma, or Mendocino Counties. In addition to contaminating the grape bunches, the principal damage is caused by the larvae feeding on the berries and stems within the berry clusters. Stem feeding in the cluster causes berry drop and, in some cases, when the stem is cut or girdled, portions of the cluster below the injury are killed. Larval feeding on berry clusters may also provide an avenue for infection by spoilage microorganisms.