A total of 33 corn hybrids were evaluated in a series of greenhouse and field trials to determine if they differed in resistance to either Meloidogyne incognita race 3 or M. arenaria race 1. Reproduction of M. incognita race 3 and M. arenaria race 1 on the hybrids was also compared. Reproduction of M. arenaria differed among corn hybrids after 58 to 65 days in greenhouse experiments; however, r...

The localization of cytokinins in corn root tips was investigated using antibodies or antibody fragments directed against dihydrozeatin riboside and labeled with rhodamine or colloidal gold. Roots were sectioned at -30 degrees to -40 degrees for immunofluorescence or freeze-substituted in ethanol or acetone and embedded in plastic for electron microscopy. Meristematic cells surrounding the quie...

The antibiotic 2,4-diacetylphloroglucinol (DAPG), produced by some strains of Pseudomonas spp., is involved in suppression of several fungal root pathogens as well as plant-parasitic nematodes. The primary objective of this study was to determine whether Wood1R, a D-genotype strain of DAPG-producing P. fluorescens, suppresses numbers of both sedentary and migratory plant-parasitic nematodes. An...

Endogenous variables in structural models of agricultural commodity markets are typically treated as stationary. Yet, tests for unit roots have rather frequently implied that commodity prices are not stationary. This seeming inconsistency is investigated by focusing on alternative specifications of unit root tests. We apply various specifications to Illinois farm prices of corn, soybeans, barro...

The plasma membrane H(+)-ATPase (PM-H(+)-ATPase) of barley (Hordeum vulgare L. cv Klondike) roots was assayed by cross-reaction on western blots and cryosections with an antibody against the PM-H(+)-ATPase from corn roots. Under conditions of reduced K availability, which have previously been shown to increase K influx by greater than 25-fold, there were only minor changes detected in PM-H(+)-A...

Greenhouse experiments were conducted to evaluate the effect of Nod factor Nod Bj-V (C18:1, MeFuc) of Badyrhizobium japonicum on the growth of soybean and corn. Three-day-old seedlings of soybean and corn were grown in hydroponic solutions containing four concentrations (0, 10(-7), 10(-9) or 10(-11) M) of Nod factor. After 7 d of treatment, Nod factor enhanced soybean and corn biomass. Nod fact...

The level of asparagine synthetase is low in 10-mm root tips from corn seedings (Zea mays W64 x W182F) but relatively high in mature root sections taken 20 to 35 mm from the tip. When root tips are excised there is a marked increase in asparagine synthetase over a 5-hour period. In mature root sections, on the other hand, the asparagine synthetase activity declines over the same 5-hour period. ...

ABSTRACT The population density of the reniform nematode, Rotylenchulus reniformis, was monitored at depths of 0 to 30, 30 to 60, 60 to 90, and 90 to 120 cm in a tillage and crop sequence trial in south Texas in 2000 and 2001. Main plots were subjected to three different tillage systems: conventional tillage (moldboard plowing and disking), ridge tillage, and no-tillage. Subplots were planted w...