REPLANT PROBLEM AND CHEMICAL-COMPONENTS OF ASPARAGUS ROOTS

Crop failures associated with asparagus replanting have been ascribed to a combination of microbiological and chemical influences. Extracts from asparagus roots and soil were examined to locate inhibitory chemi cals. Analysis of root extract fractions in a seedling assay showed th at phenolic and saponin components inhibited growth but the most inhib itory material was located in the amino acid/carbohydrate fraction. Ho wever, inhibitory asparagus soil extracts did not contain significant levels of active compounds (tryptophan, caffeic acid) identified from root extracts.