Evaluation of Soybean Cultivars for Production in Meloidogyne arenaria Race 2-Infested Soil.

Field trials with 56 soybean cultivars and breeding lines from public and private sources were conducted from 1986 through 1988 at a site infested with Meloidogyne arenaria race 2. Differences (P < 0.05) among yields were found each year and yields were negatively correlated (P < 0.

Evaluation of Soybean Cultivars for Production in Meloidogyne incognita-infested Soil.

Significant (P < 0.05) differences among galling and yields of 41 soybean cultivars and breeding lines were found when they were produced at a site infested with Meloidogyne incognita during 3 years of investigation. Over a period of 6 years of testing, 13 cultivars were identified as having a suitably low susceptibility to warrant their production in M.

Galling and Yields of Soybean Cultivars Grown in Meloidogyne arenana-Infested Soil.

Field trials with 39 soybean cultivars and five breeding lines from public and private sources were conducted from 1982 through 1985 at sites infested with Meloidogyne arenaria. Nematode population densities and root-knot galling were measured for each soybean entry. All were efficient hosts for the nematode, and average juvenile numbers in the soil increased 5-50 x from planting to harvest.

On the nature of the stimulation of the lipoxygenase from rabbit reticulocytes by biological membranes.

The oxygenation of concentrated emulsions (about 260 microM) of arachidonic acid or linoleic acid catalyzed by the purified lipoxygenase from rabbit reticulocytes is strongly stimulated in the presence of low concentrations of beef heart submitochondrial particles or other membrane preparations. Maximal stimulation was observed at a proportion of about 5 mumoles polyenoic acid per mg of membrane protein. Whereas at a constant ratio of arachidonic acid and membranes the reaction rate obeyed the Michaelis-Menten kinetics with an apparent Km value of 75 microM for arachidonic acid, sigmoid kinetics was observed under conditions of constant concentration of membranes and, consequently, varying proportions of arachidonate and membranes.

The mechanism of inactivation of lipoxygenases by acetylenic fatty acids.

The inactivation of soybean lipoxygenase by 5,8,11,14-eicosatetraynoic acid was studied in detail. The inactivation was found to be time-dependent and irreversible. A kinetic scheme, based on the assumption of a rapid inactivation of the enzyme-product complex, yielded a Km value for 5,8,11,14-eicosatetraynoic acid of 1.