الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 132 |  |  |
| | | from | 132 | | |
Abstract
The objective of this study was to evaluate the efficacy of some dusts i.e. diatomaceous earth dust , silica gel dust , magnesium carbonate dust and katel sous against T . castaneum and T. granarium at 30, 20 ±1°C and 65 ± 5 % R.H. Meanwhile, the efficacy of two organphosphorus insecticides namely malathion and primiphos-methyl (actellic) and one botanical insecticides (neemazal 1% Azadrachtin) were evaluated against T. castaneum and T. granarium at 30, 20 ±1 ° C and 65 ± 5 % R.H.
Besides , the efficacy of controlled atmosphere (CA) of various carbon dioxide concentrations ( 25 ,50 ,75 ,100 % ) against various stages of T. castaneum and active as well as diapause larvae of T . granarium at 30 , 20 ±1 ° C and 65 ± 5 % R.H. was investigated . Also, the efficacy of CA of 99 % N2 against the various stages of T. castaneum and active, diapause larvae of T. granarium at the two mentioned temperatures and relative humidity was studied. Further more, the efficacy of CA of various concentrations (99 % N2 + 1 % O2; 98 % N2 + 2 % O2; 96 % N2 + 4 % O2; 91 % N2 + 4 % O2 + 5 % CO2 and 86 % N2 + 4 % O2 + 10 % CO2) against active, diapouse larvae of T. granarium at 30, 20 ±1 ° C and 65 ± 5 % R.H. was investigated. Experiments were performed at the laboratory of the plant protection department of the Faculty of Agriculture, Moshtohor, Benha University. Carbon dioxide and Nitrogen gases were provided as pure gas in pressure cylinder which connected with pressure regulators.
1- Efficacy of dusts against the adults of Tribolium castaneum and active, diapause larvae of Trogoderma granarium :-
Crushed Wheat grains were used for Tribolium castaneum and treated with various concentrations ( 8 , 6, 4 , 2 , 1 % w/w ) of different tested dusts in the laboratory while in case of T.granarium wheat grains were treated with various dust concentrations ( 16 , 8 , 4 , 2 , 1 % w/w ) at 30 , 20 ± 1 ° C and 65 ± 5 % R.H. each replicate was infested with 30 adults (1-2 week old) of Tribolium castaneum and 30 active or diapausing larvae of Trogderma granarium. Mortality values were recorded after 1, 3, 5, 7, 14 and 21 days from treatment. The results revealed the following:-
Tribolium castaneum adults:-
1- Diatomaceous earth dust:-
The results showed that adults mortality increased by increasing the dust concentration and period of exposure. Adult mortality of T. castaneum after 21 days post – treatment with various concentrations of diatomaceous earth dust was between 30– 90 % and 45.4- 80.9% at 30, 20 °C, respectively.
The reduction rate in progeny of T. castaneum was from 63.7 – 95 % at 30 °C. % the estimated lethal concentrations of DE for 95 % kill of T. Castaneum adults were 5.0 % , and 6.2 % (w/w) after 21 days post treatment, respectively. At 8% concentration mortality was 6.7 % after 1 day exposure and increased to 80.9% after 21 days post treatment at 20± 1°C and 65±5 %. The reduction rates in progeny of T. castaneum were from 54-80% and 50 – 80 % at 30, 20 °C, respectively. The estimated The LC50 values decreased significantly at the longest exposure period 21 days to the lowest values 1.98 and 3.12 % at 30 and 20 °C, respectively. The LT50 values was 5.5 days and increased to 6.2 days at 2 0 ° C at 30, 20°C respectively. At 30°C, DE- dust was more effective against T.castaneum adults than at lower temperature (20°C).
2- Katel sous dust:-
The result indicated that adult mortality of T. castaneum after 21 days post – treatment with various concentrations of Katel sous dust was between 21.1-80 % and 27.8 – 77.8 % at 30, 20 °C, respectively. Reduction in progeny was between (17.5- 90 %) for the various tested concentration of katel sous dust at 30°C and 15.2- 86.3% at 20°C. The LC50 values at the longest exposure period of 21 days were 5.2 and 10.7 % at 30 and 20 °C, respectively. At 8% concentration the LT50 values were 6.0 and 10.1 days at 30 and 20°C, respectively.
Trogoderma granarium larvae :-
1- Diatomaceous earth dust:-
The results showed that larvae mortality increased by increasing the dust concentration and period of exposure. Mortality of active larvae of T. granarium after 21 day post treatment with various concentrations of Diatomaceous earth dust was between 27.8– 90 .7 % at 30°C and 20- 70 % at 20 °C . The LC50 values at the longest exposure period of 21 day amounted 1.97, 3.32 % at 30 and 20°C, respectively. At 16 % concentration the LT50 values were 4.1 and 6.12 days at 30, 20°C, respectively. The results indicated clearly that mortality was increased by increasing the dust concentration and the period of exposure. Mortality of diapause larvae of T. granarium after 21 day post treatment with various concentrations of diatomaceous earth dust was between 19 – 77.7 % and 20 – 70. 5 % at 30, 20 °C, respectively. The LC50 values at the longest exposure period (21 day) amounted 1.9, 3.3 % at 30 and 20°C, respectively. At 16 % concentration the LT50 values were 6.0 and 7.28 days at 30, 20°C respectively. Active larvae were more sensitive to DE- dust than diapause larvae at the two test temperatures.
2- Katel sous dust:-
The results showed that larvae mortality increased by increasing the dust concentration and period of exposure. Mortality of active larvae of Trogoderma granarium after 21 days post treatment with various concentrations of katel sous dust was between 17.8 – 75 % and 10 – 60 % at 30, 20 °C, respectively. The LC50 values at the longest exposure period 21 days were 8.0, 8.6 % at 30 and 20°C, respectively.
At 16 % concentration the LT50 values were 8.0 and 8.6 days at 30, 20°C, respectively. The results showed indicated clearly that mortality was increased by increasing the dust concentration and the period of exposure. The result indicated that mortality of diapause larvae of Trogoderma granarium after 21 days post treatment with various concentrations of katel sous dust was between 15.7 – 72.3 % and 11.1 – 55.6 % at 30 , 20 °C , respectively. The LC50 values after 21 days post treatment were 8.0, 8.6 % at 30 and 20°C, respectively. At 16 % concentration the LT50 value was 8.0 and 8.6 days at 30, 20°C, respectively. Diapause larvae were more tolerant against KS- dust than active larvae at the two test temperature.
3- Silica gel dust:-
The results showed that the mortality increased by increasing the dust concentration and period of exposure. Mortality of active larvae of Trogoderma granarium after 21 days post treatment with various concentrations of silica gel dust was between 33.3 – 93 % and 25 – 86 % at 30, 20 °C, respectively. The LC50 values at the longest exposure period 21 days amounted 10.0, 15.2% at 30 and 20°C, respectively.
At 16 % concentration the LT50 values were 10.0 and 15.0 days at 30, 20°C, respectively. The results showed clearly that mortality was increased by increasing the dust concentration and the period of exposure. Mortality of diapause larvae of Trogoderma granarium after 21 days post treatment with various concentrations of silica gel dust was between 33.3 – 90.3 % and 26.7 – 79 % at 30, 20 °C, respectively. The LC50 values at the longest exposure period 21 days amounted 2.8, 3.8 % at 30 and 20°C, respectively. At 16 % concentration the LT50 value was 4.0 and 5.1 days at 30, 20°C, respectively. Diapause larvae of T.granarium were more tolerant to silica gel dust than active larvae at the two test temperatures.
4- Magnesium carbonate:-
The results showed that the mortality increased by increasing the dust concentration and period of exposure. Mortality of active larvae of Trogoderma granarium after 21 days post treatment with various concentrations of magnesium carbonate dust between 25.6 – 89 % and 20 – 75.6 % at 30, 20 °C, respectively. The LC50 values at the longest exposure period 21 days amounted 2.0, 5.5 % at 30 and 20°C, respectively. At 16 % concentration the LT50 values were 9.8 and 10.0 days at 30, 20°C, respectively. The results showed indicated clearly that mortality was increased by increasing the dust concentration and the period of exposure. Mortality of diapause larvae of Trogoderma granarium after 21 days post treatment with various concentrations of magnesium carbonate dust was between 31.1 – 85.9 % and 21.1 – 67.9 % at 30 , 20 °C , respectively . The LC50 values at the longest exposure period 21 days were 2.7, 4.5 % at 30 and 20°C, respectively. At 16 % concentration the LT50 values were 7.0 and 7.6 days at 30, 20°C, respectively. Active larvae of T.granarium were more sensitive to magnesium carbonate dust than diapause larvae at the two test temperatures.
2- Efficacy of insecticides against the adults of Tribolium castaneum and active, diapouse larvae Trogoderma granarium:-
Tribolium castaneum adults:-
1- The botanical insecticide neemazal:-
The tested concentrations were 200, 100, 50, 25 and 12.5 ppm. The results showed that adult mortality was concentration and exposure time dependent. Mortality increased with rising the insecticide concentration and the period of exposure. After 21 days post – treatment T.castaneum adult mortality was between 60 – 99.9 % at 30 ° C and 28.3 – 75 % at 20° C for the various tested concentrations. The LC50 values 14 days exposure were 6.4 and 10.5 ppm at 30 and 20 °C, respectively.
At 200 ppm concentration the LT 50 values for the adults of T. castaneum were 10.3 and 14.7 days at 30, 20°C, respectively.
2-Actellic ( primiphos-methyl):-
The LC 50 of primiphos- methyl was 1.2 and 3.4 ppm at 30 and 20°C, respectively for T.castaneum adults.
3- Malathion:-
The LC 50 of malathion for adults of T. castaneum was 3.0 and 3.8 ppm at 30 and 20°C, respectively.
Trogoderma granarium larvae:-
1- The botanical insecticide neemazal:-
The tested concentrations were 200, 100, 50, 25 and 12.5 ppm. The results showed that T.granarium larva was concentration and exposure time dependent. Mortality increased with increasing the neemazal concentration and the period of exposure. After 21 days post – treatment active larvae mortality was between 26.7- 95.6 % at 30°C and decreased to 20- 82.2 % at 20°C for the various tested concentrations. Diapause larvae mortality values after 21 days post – treatment was between 28.9 – 92.2 % at30°C and 15.5 – 82.5 % at 20 °C. The lethal concentrations for 50 % kill diapause larvae of T.granarium was 25.7 and 27.3 ppm at 30 and 20 °C, respectively. The lethal concentrations for 50 % kill active larvae 12.2 and 15.8 ppm at 30 and 20 °C, respectively.
The LT50 value at 200 ppm for diapause larvae was 20.73 day at 30°C and increased to 25.36 day at 20°C. The lethal time values at 200 ppm neemazal concentration. At 200 ppm for active larvae was 17.9 and 21.1 days at 30, 20°C, respectively.
2-Actellic ( primiphos-methyl):-
The LC 50 of primiphos methyl for active larvae of T.granarium was 3.2 and increased to 4.6 ppm at 30 and 20°C, respectively. The LC 50 for diapause larvae was 5.0 and 6.5 ppm at 30 and 20°C, respectively.
3- Malathion:-
The LC 50 for the diapouse larvae of T.granarium was 7.1 and 11.7 at 30 and 20°C, respectively. The LC50 for active larvae was 3.5, 7.5 ppm at 30 and 20°C, respectively.
3 -Efficacy of controlled atmosphere (CA) containing various CO2 concentrations ( 25 , 50 , 75 , 100 % ) against various stages of Tribolium castaneum and active, diapause larvae Trogoderma granarium :-
Experiments were conducted in recirculatory glass apparatus in the laboratory at 20 and 30°C and 65 ±5 % R.H. Gases tested at fixed CO2 concentration. The results showed that the efficacy of CO2- CA increased with rising the concentration and the time of exposure. At higher temperature ( 30 °C) , the efficacy of the CA of various CO2 concentrations, was higher against different stages of Tribolium castaneum and active , diapause larvae of Trogoderma granarium than at lower one (20 °C). CA of 100 % CO2 caused 50 % mortalities of Tribolium castaneum stages at 0.1, 0.3 and 0.9 days and 0.3, 0.4 and 1.5 days at 30, 20°C, respectively for the adults, larvae and pupae, respectively. CA of 75 % CO2 caused 50 % mortalities of Tribolium castaneum stages at 0.4, 0.1 and 1.0 days and 0.5, 0.6 and 2.2 days at 30, 20°C, respectively for the adult, larvae and pupae, respectively. The corresponding values with CA of 50 % CO2 caused 50 % mortalities of Tribolium castaneum stages at 0.5, 0.7 and 2.4 days and 0.5, 1.4 and 4.0 days at 30, 20°C, respectively for the adult, larvae and pupae, respectively. Using CA of 25 % CO2 caused 50 % mortalities of Tribolium castaneum stages at 1.1, 1.2 and 4.0 days and 1.5, 2.5 and 5.0 days at 30, 20°C, respectively for the adults, larvae and pupae, respectively.
4 - Efficacy of CA of 99 % N2 +1%O2 against various stages of Tribolium castaneum at 30 and 20 °C.
The result indicated clearly that the efficacy of CA of 99 % N2 was insect stage, exposure time and temperature dependent. Rising the exposure period and the temperature resulted in higher efficiency. The time needed to achieve 50 % insect mortality using CA of 99 % N2 was 0.5, 1.1 and 1.5 days and 1.1, 1.4 and 2.0 at 30, 20°C, respectively for the adult, larvae and pupae, respectively.
Trogoderma granarium larvae:-
5- Efficacy of controlled atmosphere (CA) containing various CO2 concentrations (25, 50, 75, 100 %) against the active and diapause larvae of Trogoderma granarium :-
Time of CA of 100 % CO2 caused 50 % mortality of Trogoderma granarium were 0.4 and 0.8 days at 30 , 20°C, respectively for active larvae and 2.1 and 4.6 days for diapause larvae at 30 , 20°C, respectively. Time of CA of 75 % CO2 caused 50 % mortality of Trogoderma granarium were 0.4 and 0.9 days at 30, 20°C, respectively for active larvae and 5.4 and 8.9 days for diapause larvae at 30, 20°C, respectively. CA of 50 % CO2 caused 50 % mortality of Trogoderma granarium were 0.5 and 0.9 days at 30, 20°C, respectively for active larvae and 6.0 and 9.0 days for diapause larvae at 30, 20°C, respectively for diapouse larvae. Using CA of 25 % CO2 caused 50 % mortality of Trogoderma granarium after 0.5 and 2.0 days at 30, 20°C, respectively for active larvae and 6.7 and 10.0 days for diapouse larvae at 30, 20°C, respectively.
6- Efficacy of controlled atmosphere (CA) containing various concentrations of N2 and mixture of N2 and CO2 against larvae of Trogoderma granarium at two temperatures 30 and 20 ±1°C.
The results indicated that the efficacy of CA of 99 % N2 was insect stage, exposure time and temperature dependent. Rising the exposure period and the temperature resulted in higher efficiency. The time needed to achieve 50 % larval mortality using CA of 99 % N2+1%O2 was 2.0 and 3.4 days for active larvae and 6.6 and 8.2 days for diapause larvae at 30, 20°C, respectively. The time needed to achieve 50 % of T. granarium larval mortality using CA of 98 % N2+2%O2 were 2.5 and 4.0 days for active larvae and 4.3 and 5.9 days for diapause larvae, respectively at 30, 20°C, respectively. The time needed to achieve 50 % larval mortality using of CA 96 % N2+4 %O2 were 3.2 and 6.1 days for active larvae and 6.6 and 8.0 days for diapause larvae at 30, 20°C. The time needed to achieve 50 % larval mortality using of CA 91 % N2 + 4 %O2 + 5%CO2 was 4.2 and 5.0 days for active larvae and 5.2 and 9.2 days for diapause larvae at 30, 20°C. The time needed to achieve 50 % larval mortality using of 86 % N2 + 4 %O2 + 10 %CO2 was 5.3 and 6.1 days for active larvae and 6.2 and 9.7 days for diapause larvae at 30, 20°C, respectively.