Avermectins are a group of potent anthelmintic agents produced by Streptomyces avermitilis. They are active at extremely low dosages and are now in commercial use. In this study, the synthesis of two segments of avermectin B[subscript 1a] are described. The synthesis of the hexahydrobenzofuran subunit (segment A) began with the...
A silvopastoral system using a Douglas-fir
(Pseudotsuga menziesii) tree crop and subclover (Trifolium subterraneum) as a nitrogen-fixing forage crop was
investigated near Corvallis, Oregon, during 1983-1985.
Treatments included all possible combinations of three
planting patterns (no trees, trees planted 2.5 m apart in a
grid, and clusters of five trees...
The response to glyphosate [N-(phosphonomethyl) glycine] of two
dodder species Cuscuta campestris Yuncker (field dodder) and Cuscuta
indecora Chiosy (largeseed dodder) parasitizing alfalfa (Medicago
sativa L.) was compared. In the absence of glyphosate, alfalfa was
killed or severely injured by parasitism from uncontrolled dodder.
Results of field experiments in which...
It has been shown by Schlesinger and Mintz (1979) that the UCLA general
circulation model (GCM) is able to simulate the observed negative correlation
between the total amount of ozone in a vertical atmospheric column (the total ozone)
and the eastward-propagating synoptic disturbances in the troposphere, with the