الفهرس 
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Abstract
The present work was carried out at the Laboratory of Pesticides Biotechnology and Molecular Toxicology and Insecticide Bioassay Laboratory (Plant Protection Department), Food Safety Laboratory (Food Sciences Department) and Microbial Genetic Laboratory (Agricultural Genetic Department), Faculty of Agriculture, Zagazig University to investigate the following:
1- The efficacy of seven compounds belonging to different seven main groups of insecticides against the fourth instar larvae of T. absoluta under laboratory conditions.
2- The determination of tolerance degrees in two different field populations at Sharkia governorate to the tested compounds compared with the laboratory reference strain.
3- The changes in some biological aspects in the most tolerant T. absoluta field population compared with the laboratory reference strain.
4- The biochemical and molecular diagnosis (protein profile and DNA profile) of insecticides tolerance in two T. absoluta field populations compared with the laboratory reference srain.
5- Residues of lambda-cyhalothrin in tomato fruits.
1. Toxicity of the tested insecticides to T. absoluta.
The relative susceptibility of T. absoluta fourth instar larvae of the two field populations collected from El- Salhia (Sami Saad Region, SSR) and (Abo- Kabeer Region, AKR) was assessed to lambda-cyhalothrin, chlorpyrifos, chlorantraniliprole, imidacloprid, emamectin benzoate, spinosad and indoxacarb compared with the laboratory strain. The obtained results can be summarized in the following points:
1.1. El- Salhia Population.
The oxadiazine insecticide (indoxacarb) was the most was the most toxic compound recording the least LC50 value (0.85 µg/ mL). Spinosad come in the second position of toxicity (0.92 µg/ mL) followed by descendingly by emamectin benzoate, chlorantraniliprole, lambda-cyhalothrin, imidacloprid and chlorpyrifos. The corresponding values of LC50 were 1.73, 29.48, 1003.78, 1319.16 and 3108.62 µg/ mL, respectively.
1.2. Abo- Kabeer Population.
Also, it was observed that indoxacarb was the most toxicity against the tested insect pest followed by emamectin benzoate, spinosad, chlorantraniliprole, lambda-cyhalothrin, chlorpyrifos and imidaclopride, respectively. The corresponding figures of indoxacarb, emamectin benzoate, spinosad, chlorantraniliprole, lambda-cyhalothrin, chlorpyrifos and imidacloprid were 0.15 and 0.46 µg/ml; 0.18 and 0.32 µg/ml; 0.25 and 0.04 µg/ml; 3.97 and 19.63 µg/ml; 173.17 and 91.73 µg/ml; 282.82 and 34.12 µg/ml; and 492.96 and 363.05 µg/ml for the same locality and laboratory reference strain, respectively.
2. Insecticides tolerance spectrum in two field populations of T. absoluta compared with the laboratory reference strain.
2.1. El- Salhia Population.
According to the values of tolerance of El- Salhia populations, it seems clearly that at the base of LC50, all populations exhibited different degrees of tolerance to the tested compounds comparing with the laboratory strain. The highest levels of tolerance were found against chlorpyrifos, spinosad and lambda-cyhalothrin (91.11-, 23.00- and 10.94- fold, respectively). At LC90 level, high levels of resistance were also recorded towards chlorpyrifos, emamectin benzoate and spinosad (139.23-, 41.08- and 10.78- fold, respectively) compared with the laboratory strain. The other four compounds (chlorantraniliprole, indoxacarb, imidaclopride and emamectin benzoate) exhibited low levels of tolerance ranged between 1.5- to 5.41- fold agains.
2.2. Abo- Kabeer Population.
According to the values of tolerance level, the data showed that Abo- Kabeer population exhibited different degrees of tolerance to the tested compounds comparing with the laboratory strain. The highest levels of tolerance were found against chlorpyrifos and spinosad (8.29- and 6.25- fold, respectively). At LC90 levels, low levels of tolerance were also recorded towards spinosad and chlorpyrifos (7.28- and 4.26- fold, respectively) compared with the laboratory strain.
3. Changes in some biological aspects of the most tolerant T. absoluta population to some tested insecticides compared with the laboratory reference strain.
The effect of tolerance to some insecticides (chlorpyrifos, spinosad and lambda-cyhalothrin) on some biological aspects of T. absoluta compared with the laboratory reference strain, namely larval and pupal durations, pupation percentages, adult emergence percentages, sex ratio, adult longevity, female fecundity of eggs, incubation period, complete developmental period and generation period were tested.