This investigation was undertaken to determine 1) the effects
of various carbon sources in defined media on pectolytic enzyme production,
2) the effect of the incubation period on pectolytic enzyme
activity, and 3) the development of improved methods for the purification
and characterization of the polygalacturonases (PG) produced
by Fusarium...
This study was undertaken to determine the sorts of polygalacturonases
present in the culture filtrate of Fusarium oxysporum
f. sp. lycopersici, to purify and characterize these enzymes, and to
study any complexes that may form between polygalacturonase and
carbohydrate not degraded by the enzyme.
The polygalacturonase in culture filtrate consists...
An assay for fungicidal activity of sodium N-methyldithiocarbamate
(Na-MDC) and its decomposition products was developed
in which there was a minimum influence due to the widely varying
physical properties of the compounds (i.e. vapor pressure and water
solubility). Decomposition of the toxicant during the tests was
measured and held to...
The demand for new fungicides to control plant diseases has
led to experimentation with both previously used and newly developed
fungicides. Silver, an older but little used fungicide, was selected for
evaluation because of its high toxicity to microorganisms. Silver
nitrate and a silver electrolytic cell were tested as potential...
Previous research has shown that activated carbon is effective
in inactivating certain herbicides applied as a preemergence treatment.
Studies were conducted in the greenhouse to determine the
influence of various factors on the ability of activated carbon to
inactivate herbicides applied after carbon application. Field studies
were conducted to determine...
Previous research has indicated several soil-applied herbicides
are more effective by exposure to emerging shoots than from
root uptake. Studies were conducted in the greenhouse and growth
chamber to investigate effects of herbicide placement in soil on
toxicity to emerging seedlings.
In these studies, an inch of treated soil was...
Mycelial growth of Endothia parasitica was
stimulated by
relatively high concentrations of CuSO₄ in potato dextrose agar
medium (PDA).
Stimulation of E. parasitica by the high levels of
CuSO₄ and the relatively poor growth of this fungus on
standard culture
media suggested that stimulation might be due to
interaction of...
The formation of cytosine hydroperoxide was detected in
aqueous cytosine solutions irradiated with Co-60 γ-rays at pH 2.
The nucleotide of cytosine, cytidylic acid, forms a hydroperoxide
which was detected in neutral solution. The stability of the hydroperoxides of cytosine, thymine, and their nucleotides was found to
be a function...