Time Needed for Population Extinction of Certain Stored Product Insects Using Modified Atmosphere of High Nitrogen Content Inside Steel Bins.

• El-Lakwah, F. A . (1); A.M. Abd El-Latif (2); G.H. Rady(1) And H. M . Nour Eldin(1)
• (1) Plant Protection Dept., Fac. of Agric. Benha Univ., Egypt.
• (2) Plant Protection Research Institute, ARC, Giza , Egypt.
• The Third International Conference onIPM Role in Integrated Crop management and Impacts on Environment and Agricultural Products. 26-29 November 2005, Giza, Egypt.

Abstract

Modified atmosphere (MA) of 99% N2 at grain temperatures of 18 and 28± 2°C was used as control method for the adults and immature stages of Sitophilus oryzae, Rhizopertha dominica and Triblium castaneum as well as the active and diapausing larvae of Trogoderma granarium inside gas-tight steel bins. The obtained results indicated that efficacy of MA 99% N2 was differed according to the tested insect, treated stage, temperature, and exposure period. The lethal times required to achieve population extinction of the different stages of S. oryzae at 18±2?C were 10, 35, 28 and 35 days for adults, eggs, larvae and pupae, respectively. While these values decreased to 7, 28, 21 and 28 days at 28±2?C, respectively. For R. dominica they were 14, 35, 28 & 35 days at the first temperature and 10, 28, 21 and 28 days at the second one, respectively. As for T. castaneum, these values were 14, 21, 10 & 14 days and 10, 14, 7 and 10 days, respectively. Active larvae of T. granarium were more susceptible (28 days) than diapaused ones (35 days) at 18±2?C, while the susceptibility of these insects were not differed (28 days) at 28±2?C. In general, results revealed that the pupa and egg stages of the different insects were more tolerant to MA of 99% N2 than other stages.