J. Econ. Entomol. 84(2). 638-643 (1991) ABSTRACT Alate aphids (Homoptera: Aphididae) were collected at weekly intervals in 1988 in six California sugarbeet fields-three on each side of a boundary line which separates overwintered spring harvest beet fields in Solano County from fall harvested fields in Yolo County. Alate aphids landing on a yellow board during a 45-min morning collection period...

Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitratenitrogen (NO3-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO3-N concentrations in soil water at a 76 cm depth under ir...

The duration of the embryogenic development of Nacobbus aberrans (= N. batatiformis) took 9-10 days at 25 C and 51 days at 15 C. The J molted in the egg; hence the Je emerged from the egg. The effect of distilled water attd root leachates of kochia and sugarbeet was investigated at 5, 10, 15, 20, and 25 C. Root leachates did not significantly affect the percent of cumulative hatch of eggs, but ...

parasite weeds are the most important yield reducing factors, and among them dodder (cuscuta campestris l.) is an obligate parasite of many plant families. in order to find a suitable biocontrol agent for dodder a study was conducted based on a randomized complete design with four replications at research greenhouse of faculty of agriculture, ferdowsi university of mashhad, iran during 2007-200...