الفهرس 
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Abstract
Lesser grain borer, Rhyzopertha dominica (F.) (Col-eoptera: Bostrychidae), ranks the 3rd in terms of per-centage distribution of insects causing reduction in wheat. Alone it causes 10% reduction in the wheat in Egypt. The current study aimed to find out an insecti-cidal substitute, safe to environment and efficient in con-trolling the adults of this pest on wheat grains. Two formulations of entomopathogenic fungus, Beauveria bassiana (BotaniGard and Biosect), and two formula-tions of diatomaceous earth (DE) (Insecolo and Food-grade), used alone or in combination were investigated for:
1- Their insecticidal efficiency.
2- Their effect on some biological aspects (number of emerged adults and their effect on the eggs).
3- The persistence of their insecticidal efficiency.
4- Their effect on the wheat grains (germination and water absorption).
The most promising fungus, Biosect was selected for in depth study i.e.
1- Its effect on some biochemical properties of wheat grains (total protein, total sugars, starch, crude fi-bers and ash content).
2- Its effect on baking quality of bread (physical measurements and sensory evaluation).
3- Its effect on albino rats (liver and kidney func-tions).
The following is a brief summary on the obtained results, findings and observation:
1-Insecticidal efficiency of B. bassiana and DE alone or in combination on R. dominica adults:-
A. The data obtained indicated that adults mortalities increased with increasing concentrations of all tested powders and with increasing exposure time. The toxicity values of the tested powders are arranged according to LC50 s in the following order: Insecolo > Biosect > Foodgrade > BotaniGard.
Insecolo, Foodgrade and Biosect strongly enhanced the potency of the BotaniGard.
-Joint action study of Biosect, Insecolo and Food-grade on toxicity of BotaniGard revealed that all tested powders increased the toxicity of BotaniGard except Foodgrade at LC10 which showed antagonistic effect.
B. Results of the effect of DE and B. bassiana for the control of the R. dominica eggs expressed as number of adult emerged indicate that:
- The tested powders significantly reduced the num-ber of emerged adults. At LC50, the number of emerged adults was significantly decreased due In-secolo, Foodgrade followed by BotaniGard and then Biosect, respectively, compared to the con-trol.
- However, at LC95 for all tested powders adults emergence was completely suppressed.
- All tested mixtures were able to prevent adult emergence completely, except the mixtures of the LC25 of the two tested materials.
C. Residual activity:
- The integration of B. bassiana and DEs showed their potential for long-term grain protection. The presence of DE in grains not only increased the levels of adult mortality but also enhanced the re-sidual effectiveness of B. bassiana.
- Residual activity was gradually decreased with the increasing of storage periods up to 12 weeks for all tested powders and their mixtures.
2-Effect of B. bassiana and DE on wheat grains:-
A. No adverse effect on the germination and growth parameters of wheat grains due to Botan-iGard, Biosect, Insecolo and Foodgrade treatment.
-At both initial time and after the storage periods, no side effect on germination of wheat grains treated with all tested powders at LC50 and LC95. With exceptions noted in BotaniGard at LC95 caused an obvious decrease in the rate of germina-tion energy after the storage periods without harm to the germination percent (>75 %, Minimum Seed Certification Standards).
- Insignificant increase in growth parameters based on root /shoot ratio and the vigor index were im-proved at initial application and after storage pe-riods.
- B. bassiana and DE combinations at all applica-tion and all conditions did not affect the viability of wheat grains. However, the mixture of Botan-iGard at LC75 and Insecolo at LC25 is not indicat-ed for storage since it has adverse effect on the vigor index.
- At LC95 ”the concentration level indicated for protection by Ministry of Agricultural” for storage of wheat grains. No adverse effect was observed for water absorption, at the recommended storage period (12 week).
- Application of different mixtures did not affect the wheat grains water absorption at the recom-mended storage period.
B. Biochemical constituents and baking quality:
The following results are obtained after treatment of wheat grains with LC95 of B. bassiana (b) ”Bio-sect”.
- All determined properties (total proteins, total carbohydrates, fat, starch, crude fiber, ash con-tent) were significantly increased in wheat grains. However, starch and ash contents showed signifi-cant decrease, at both initial and after storage pe-riod.
- Values of the metabolic energy for the wheat grains treated with LC95 of the Biosect at the ini-tial time and after 12 weeks storage were higher than the metabolic energy in control.
- No significant variation was recorded for baking quality of bread-treated flour at the initial and af-ter 12 weeks storage.
- Bread samples had good acceptability for all pa-rameters when compared with control samples.
3- Effect of LC95 B. bassiana (b)”Biosect”on liver and kidney functions of albino rats:
Results indicated that LC95 of Biosect powder caused no significant altration in the biochemical param-eters of liver (albumin, ALT, AST, total cholesterol and total proteins) and kidney (creatinine and urea) on albi-no rat, fed on treated grains at the initial or after storage periods.