Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Department name when degree awarded

Biochemistry and Plant Nutrition


Keith Allred


The alfalfa seed chalcid, Bruchophagus ruddi Guss., is a jet-black hymenopteran wasp. The destructive nature of this pest has been recognized since the latter part of the nineteenth century. Every year thousands of acres of alfalfa seed are destroyed, with infestation reaching as high as 8 5 percent in some areas. In Utah the chalcid annually ruins from 5 to 25 percent of the alfalfa seed. Much of this damage goes unnoticed, as infested seed is commonly blown out in the trash during harvesting and cleaning operations . The extent of damage is not restricted to the United States. Wherever alfalfa is grown for seed, the alfalfa seed chalcid is known to have caused considerable reductions in seed yields.