(14(2):54-66)CHEMICAL CONTROL OF GRANARY INSECTS AND THE ORAL TEST OF WHITE MICE WITH INSECTICIDES

積穀害蟲在本省加害儲穀之嚴重性，因倉庫未臻理想，以致其孳生繁殖肆害；尤以中南部地區之發生情形更為嚴重，不論米、穀或雜糧均能為害。為求減少米穀儲藏之損失，自從採用靈丹粉劑(Lindane）混拌積穀儲藏以來收效頗著。惜該藥劑對於部份害蟲未能達到理想之治蟲功效，且今後是否發生害蟲對藥劑產生抗藥性，或有其他原因而未能繼續使用時，則應另行尋覓適當藥劑以代替之。因此，作者自1959年8月至1962年8月曾在室內及倉庫以多種粉劑與靈丹粉劑比較，並經進行該等藥劑對小白鼠口服試驗，玆將3年來所獲結果報告於後，以供同道之參考。 本試驗在倉庫進行試驗時承農復會補助經費，及臺灣省糧食局供借稻穀，在臺北縣之木柵、新店、中和等農會倉庫進行試驗時，各農會倉庫負責人賜予多方協助，謹此致謝。 The brown rice and grain mixing with insecticides were inoculated with testing granary insects and kept in 28-30°C ready for examination. Malathion was inferior against Rhizoperthz dominica but remaining chemicals were very effective. Premium malathion was the best for the control of Tribolium castaneum, bromodan, alodan and lindane were also effective in testing, however, premium malathion was mixed with any one of them which might increase its effectiveness. The residual effect of mixed grain, bromodan was the longest, alodan and lindane were the next, premium malathion was the shortest. Grain were mixed in the chemicals which were the same active ingredient but in low concentration and high volume seemed more effective. After six months in storage, the survial rate of insect in our treatment, bromodan was the lowest, alodan combined with premium malathion was the next, alodan or premium malathion was the worst, therefore the lindane, bromodan and alodan were same effective. After six months in storage, the insects and their population ratio found in the check except the small amount of psocids and flour mites, which were not counted, were Rhizopertha dominica Fabricius 65.13: Laemoohloeus ferrugineus Stephens 12.54: Sitotroga cerealeila Olivier 8.49: Sitophilus oryzae Linne 8.46: Oryzaephilus surina-mensis Linne 1.61: Tinea granella Linne 1.29: Lophocateres pusillus Klug 0.95: Tribolium castaneum Herbst 0.91: Tenebrioides mauritanicus Linne 0.56: Carpophilus obsoletus Erichson and Palorus subdepressus Wallaston 0.04, Tribolium castaneum was the main pest of stored corn. Oral test of adult and bady mice were fed with four above chemicals with meal over 62.5 and 50 ppm of bromodan in one year. It showed no difference in the increasing of their body wight, its offspring fed with the same dosage as adults for four months the growth rate was normal. According to the above results, 33.3 ppm of bromodan in grain against granary pests showed no influence to the human body but it was not used directly for food. The results of above testing, bromodan showed the reasonable effectiveness in the control of granary pests, its residual effect could maintain through 10 months, it was the equivalent of 0.67 kg of 5% bromodan mixed in 1,000 kg of grain thoroughtly which was received in extension. However, corn was more susceptible to Tribolium castaneum and it had better use 2.5% bromodan in 0.2% premium malathion together, i. e. 1.33 kg of 2.5% bromodan plus 0.2% premium malathion mixed in 750 kg of grain or dusted with 0.2% premium malathion on the surface and outside of grain pile bimonthly would be effective for keeping away the attack of Tribolium castaneum