Rj. Lake et al., REPLANT PROBLEM AND CHEMICAL-COMPONENTS OF ASPARAGUS ROOTS, New Zealand journal of crop and horticultural science, 21(1), 1993, pp. 53-58
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.