CONCENTRATION CHANGE OF CARBON DIOXIDE IN STORED CORN INFECTED WITH SITOPHILUS ZEAMAIS IN DIFFERENT TIME

Carbon dioxide can be generated from stored grain mass during insect damaging cereals.Concentration change of carbon dioxide may be utilized in remote monitoring of insect in grain storage which should be developed into new method on insect monitoring.Insect damaged kernel (IDK) of corm sample and carbon dioxide concentration in environment were assayed in a bin where five kilogram of bagged corn sample infested by Sitophilus zeamais Motschulsky in the density of ten adults per kilogram was inserted in corn bulk,which was stored in a bin with volume of 0.98 m³and contained 550 kilogram of corn,during time of 182 days.The IDK of the corn sample was 0.44%、2.29%、4.34%、6.96%、13.74%、29.02% and 39.28% after different time of 14 d、35 d、63 d、91 d、119 d、154 d and 182 d accordingly.The carbon dioxide concentration went up from initially 0.086% to 0.150% in seven days,near to 20 times.And the concentration changed to 0.446%、0.579%、1.248%、2.289%、2.563% and 2.896% after the days of 28 d、63 d、91 d、119 d、154 d and 182 d respectively.Insect damage in sample can caused obvious change of carbon dioxide in the bin in first seven day infestation.There was a positive correlation between insect damage and carbon dioxide in environment.