A laboratory study was carried out to demonstrate the efficiency of bean flour in the
control of two storage mites: Tyrophagus putrescentiae (Schrank, 1781) and
Aleuroglyphus ovatus (Troupeau, 1878) fed on two dried Chinese herbs: coix seed (Coix
lachtymal-jobi) and Chinese hawthorn (Crataegus pinnatifida). Five concentrations of
bean flour (0, 0.01, 0.1, 1 and 10 %) were used at 25 °C and 85+5% relative humidity
(RH) under darkness. The results indicated that the controlling effect of bean flour on T.
putrescentiae was higher than that on A. ovatus and become more noticed when its
concentration increased. The low dose of bean flour (0.01 %) generally had no toxic
effect on T. putrescentiae and A. ovatus when they fed on C. lachrymal-job and C,
pinnatijida. Mortalities of T putrescentiae on C. pinnatijىda varied from 15% to 40% and
from 26% to 61% on C. lachiymal-job due to the use of 0.1% of bean flour. Moreover, in
the case of A. ovatus, the mortalities ranged from 6% to 26% and from 15% to 51% on C.
pinnatijىda and C. lachrymal-job, respectively. After 28 days, the concentration of 1%
bean flour caused 81% and 52% mortalities of T putrescentiae and A. ovatus on C.