الفهرس 
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Abstract
The present study was carried out at the bollworm research department, plant protection research Institute, in addition, the field experiments were conducted at Menoufia Governorate by using pheromone baited trap. To determine the biochemical aspects and finger print for five strains of Pectinophora gossypiella collected from five governoratesn namely, Behira and Kafr El- Sheikh, Qalyobia Sharkia and Beni–suef. The main objective of these experiments aimed to investigate the following points: 1. Laboratory Studies: Influence of constant temperatures on the biological aspects of the pink bollworm, Pectinophora gossypiella and its relation to degree-days (DD’S). Egg stage: The time required for completion of embryogenesis decreased gradually as the temperature increased from 20 to 35oC, they were 7.2, 5.04, 3.53 and 2.71 days at 20, 25, 30 and 35oC; respectively. The threshold of development was 11.54oC. The average of thermal units required for development was 64.37 degree-days. Hatchability: The highest percentage of hatchability was 90.40 % at 25oC, whereas it was 81.10, 85.70 and 73.20 % at 20, 30 and 35oC; respectively. The constant temperature in the range of 25-30oC was the favorable zone for P. gossypiella eggs to develop and hatch.
- 021 - Larval stage: Larval duration: The averages of P. gossypiella larval duration were 30.89, 14.78, 10.69 and 7.15 days at 20, 25, 30 and 35oC; respectively. The lower threshold of development was 16.91oC. The average of thermal units required for the larva of P. gossypiella to complete its development was 121.07 degree-days. Pupation: The pupation percentage decreased gradually as the temperature increased from 20 to 35oC, they were 81, 89, 79 and 36 % at 20, 25, 30 and 35oC ; respectively. Pupal stage Pupal duration There was a negative relationship between the duration of pupal stage and temperature at the range from 20 to 35oC, where the averages of pupal period varied from 24.08 days at 20oC to 9.69 days at 35oC. The lower threshold of development was 9.70oC.The average of thermal units required for the development of pupal stage within the range of the tested temperature degrees was 244.73 DD’s. Pupal weight: The heaviest pupal weight were 2.93 and 3.99 mg. for male and female at 25oC, while the lightest weight were 1.35 and 1.99 mg. for male and female at 35oC. Generally, the weight of males was lighter than females. Adult emergence: The highest percentage of adult emergence was 92.80 % at 25oC, while the lowest one was 76.30 % at 35oC. The preferable zone
- 020 - of temperature for the development and emergence of moths was 20-30oC. Adult stage: Pre-oviposition period: There was negative relationship between the pre-oviposition period and temperature degrees at thermal range from 20 to 35oC, where they reached 4.33, 1.89, 1.63 and 1.36 days at 20, 25, 30 and 35oC; respectively. The lower threshold was 11.00oC. The average of thermal unit needed for the development of Pectinophora gossypiella ovaries to start deposing eggs was 32.26 degree-days. Oviposition period: Oviposition period decrease as temperature increased. The avareg of egg depositing periods were averaged 7.90, 4.20, 3.5 and 2.3 days at 20, 25, 30 and 35oC; respeactively. Post-oviposition period The results indicated that the P. gossypiella has not this period, where the females die directly after they finished egg-lying. Male longevity The averages of male longevity were 11.79, 6.73, 4.17 and 3.99 days at 20, 25, 30 and 35oC; respectively. The lower threshold of development was 12.12oC. The average thermal units required for male longevity was 86.36 DD’s. Female longevity The female life span averaged 13.91, 8.01, 6.03 and 5.01 at 20, 25, 30 an35 C; respectively. The lower threshold for female longevity was 10.93oC. The average of thermal units required for female to complete its development was 118.61 degree-days.
- 022 - Fecundity and fertility The female of P. gossypiella deposited eggs under all tested temperatures, but only few relatively numbers of eggs were laid at 35oC. The highest average number of eggs laid by female was 209.61eggs/female at 25oC, whereas the lowest one was 19.14eggs/female at 35oC. The highest percentage of egg fertility laid under constant temperature was 90.29% at 25oC. Sex ratio The sex ratio was approximately 1:1 at 25oC. At the preferable zone (20 and 25oC), the averages of sex ratio were (58.9% males and 41.1% females) & (51.6 % males and 48.4 % females) at both degree; respectively. The complete generation The averages duration of Pectinophora gossypiella generation were 66.50, 37.47, 27.90 and 20.91 days at 20, 25, 30 and35oC; respectively. The lower threshold of development (to) was 12.93oC. The average of thermal units required for the completion of P. gossypiella generation was 465.04 degree-days. 2. Field trials • Approximated number of annual field generations of P. gossypiella: Based on male moths activity monitoring by using sex pheromone baited traps generally, the results indicted four generations including overwintering generation, occurred during the infestation period that extended from the 1st week of May to the last week of September at the investigated cotton seasons of 2011 and 2012.
- 021 - Growing cotton season, 2011: The overwintering generation started during the 4th week of May and continued till the end of May. The 2nd generation started to appear from the 3rd week of June and continued till the last week of June. The 3rd generation started from the 3rd week of July till the last week of July. The 4th generation occurred within the 2nd week of August and continued till the first week of September. Growing cotton season, 2012 The overwintering generation occurred within the 3rd week of and continued till the last week of May. The second generation started from the last week of June and continued till the end of June. The 3rd generation started from 3rd week of July and continued till the 4th week of July. The fourth generation started from 2nd week of August till the 1st week of September. ••Seasonal variability and prediction possibility of Pectinophora gosypiella male moth population in relation to heat units accumulations: This point of investigation throw light on the influence of temperature expressed as accumulation of heat units on the P. gossypiella development moths emergence, and occurrence in the field. The expected peaks of generation could be detected when the accumulation thermal units reached 465.04±1.375 degree-days.
- 021 - The observed peak of the overwintering generation occurred at June, 3rd for 2011 and May31st for 2012, whereas the expected dates according to thermal units requirements, was 2days earlier for 2011 and 6 days earlier for 2012. The observed peaks of the 2nd generation occurred on June. 30th for both season, whereas the expected peaks occurred on June, 27th for the two seasons. Deviation between observed peak and expected peak was 3 days for the two seasons. Deviation between the observed and expected peaks of the 3rd generation exhibited 3 days earlier for 2011 and 0 day for 2012. The observed peaks of the 4th generation occurred earlier 3 days from the expected peaks during the two seasons. Generally, all generations indicated a positive relationship between DD’s and the occurrence of population peaks except in the third generation of 2012 and the fourth generation of the two seasons. 3. Field-Laboratory studies: Biochemical aspects in the pink bollworm, P. gossypiella strains: Hydrolyzing enzymes activity, i. e. acetylcholinesterase, alkaline phosphatase, carboxyl esterase and nonspecific-esterases as well as total protein contents, total carbohydrate and total lipids were determined in the 4th instar larvae of P. gossypiella strains. In this study, five different field colony strains were compared with the baseline laboratory strain that was not subjected to any insecticides. The results indicated that the 4th instar larvae of the different field colony strains showed much higher levels of the biochemical aspects the baseline laboratory strain. Beni-Suef field colony strain showed the highest levels of the enzymatic activity as well the total protein
- 021 - content than the other field colony strains. Sharkia field colony showed the highest level of carbohydrates content as compared with the other field colony strains. Behira field colony strain had the highest level of lipids than the other field colony strains. Qalubia field colony strain exhibited the lowest level of acetylcholinesterase and alkaline phosphatase activity than the other field colony strains; whereas Behira field colony strain showed the lowest levels of carboxyl esterase and α-esterases activity than the other field colony strains. 4- Finger print: Six strains of the pink bollworm, Pectinophora gossypiella were used in the present study. The laboratory strain was used as a baseline in the molecular biology assays. Five strains were selected from natural populations; fields located in Behira, Kafel-Shiekh, Qlubia, Sharkia and Beni-Suef Governorates. The molecular studies included the analysis of the plod genomic DNA of the tested strains under this study by using RAPD-PCR method. A battery of five primers was used to evaluate the mutagenic among the sex strains. Two primers (OPA-18 and OPD-03) generated the highest numbers of fragments, in which the fragments were 26 and 20; respectively. Three primers (OPB-03, OPC-02 and OPE-12) generated 12, 16 and 14 fragments; respectively. The molecular sizes ranged between.151.178 and 834.19 bp. The RAPD patterns resulted from amplification of DNA of the field colony strains and laboratory strain of the pink bollworm, Pectinophora gossypiella revealed that the lowest value of similarity index (0.0%), which reflects the highest degree of change in DNA structure and sequence between the genomes of untreated pink
- 021 - and those exposed to a wide spread of different insecticides used for controlling the pest as well as different thermal degrees in the fields. On the other hand, the two primers OPA-18 and OPD-03 recorded similarity index 1.0 between the laboratory strain and Sharkia field colony strain. The primer OPB-03 recorded similarity index 1.0 between the laboratory strain and Beni-Suef field colony strain. The primer OPC-02 recorded similarity index 1.0 between Behira and Kafrel-Sheikh field colony strains and between Qalubia and Sharkia field colony strains. Also, the primer OPE-12 recorded similarity index 1.0 between Kafrel-Sheikh and Beni-Suef field colony strains. It is interest to note that the less damaging effect to pink bollworm DNA could be attributed to a good detoxifying mechanism developed by the insect as a result of wide spread and long term exposure of insect larvae in additional to different thermal degrees in the fields.