الفهرس 
INTRODUCTION
Trapping SystemOnly 14 pages are availabe for public view
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Abstract
The present study was carried out in two locations of Assiut, the first is Arab El-Madabegh region located at the Northern West Part of Assiut at the border with Western Desert and away from Faculty of Agriculture, Assiut University by about 4.7km, while the second is Mankabad village located at North West of Assiut and away from it by about 10km. This study aims to investigate biological and ecological aspects of Tephritid flies in both the field and laboratory. In Arab El-Madabegh the Peach Fruit Fly infesting guava trees was studied while in Mankabad village the Zizyphus Fruit Fly infesting Nabaq was investigated. The obtained results could be summarized as follows:
Part I
Peach Fruit Fly (PFF):
1- Factors affecting the efficacy of trapping system to the Peach Fruit Fly males
Four types of traps; 1- Bottle trap, 2- Glass McPhail trap, 3- Plastic McPhail trap, and 4- Abdel-Kawi trap baited with different doses of Methyl Eugenol (ME) were used. Obtained results indicated that Abdel-Kawi trap charged with 0.5ml ME. was the most effective trapping system. ME seemed to be with highly attracting effect; but most of the attracted males were found on the outside surface of the trap and on the branches surround the trap. Under these conditions, the females/males ration became 1:171. Thus, the believing tactic that fruit flies populations will decline due to the lack of males in the population available to females for mating seemed to be an erroneous believing. Results proved that PFF males had the highest activity at the dawn period between 5 to 7a.m. We strongly recommend using the trapping system consists of Abdel-Kawi trap charged with 0.5ml ME only at dawn period (The first appearance of light in the morning followed by sunrise).
2- Population study
2-1- Seasonal Population trend of PFF
2-1-1- Season of 2011
Data revealed that the population never dropped to zero throughout the studied period. The minimum of 0.23 flies/trap/day was observed in the second week of December for traps suspended at 1meter height, while for those hung at 2meters height, the minimum of 0.20flies/trap/day was recorded. The population increased gradually starting from the fourth week of July to reach its first major peak throughout the second week of September with 1340.91 flies/trap/day for traps suspended at 1meter height and during the third week of September with 908.6flies/trap/day for traps hung at 2meter heights. Afterward the population trend showed a slight but gradual declining trend from the third week of September up to the third week of October. The population was then increased to reach its second major peak during the fourth week of October with 696.31 and 595.4flies/trap/day for traps hung at 1 and 2meter heights, respectively. The greatest DROP in the population captured at both trap heights was observed from the second week of November until the end of the season (2nd week of December). A total of 105270 flies/trap at both 1 and 2 meter trap height during the entire seasons of 2011 was recorded.
2-1-2 Season of 2012
The population of PFF during 2012 season followed nearly the same trend as that observed during 2011 season with minor variations. One major peak of abundance was recorded during the first week of October with 1344.37 and 955.4flies/trap/day for traps hung at 1 and 2meters, respectively. The second major peak (1104.4 and 894flies/trap/day) was observed during the fourth week of October for traps suspended at 1 and 2meters respectively. A remarkable decrease in the population could be seen from the first week of December until the end of the season (fourth week of December).
Statistical analysis of the data showed highly significant differences between fruit fly population captured at 1meter trap height (Mean = 446.997.12flies/trap/day) and that captured at 2meter trap heights (Mean = 32172.2flies/trap/day) with paired t of 4.7** and p-value of 0.0001**.
Generally, the population of B. zonata males trapped at the two studied trap heights during the whole season of 2012 was slightly higher (110966.2flies/trap) than that observed during 2011 season by about 5696.2flies/trap.
2-2- Effect of weather factors on the population density of PFF:
The results of this study showed that the attracted males exhibited a different response to the examined factors at the two trap heights and during both seasons of study. However statistical analysis indicated that the maturity level of guava fruits was the most effective variable in attracting males to Methyl Eugenol (ME) baited traps hung at 1 and 2 meter heights and had an effect on the average number of attracted males at the two height levels. The common rank of the independent variables according to the average number of males attracted to both height levels seemed to be as follows: guava maturation level (42.33%), maximum soil temperature (5.28%), maximum relative humidity (5.05%), minimum relative humidity (1.79 %), minimum soil temperature at 5cm depth (1.51%), maximum temperature (1.05%) and minimum temperature (0.48%).
3- Effect of soil depth (sand cover weight) on the emergence of PFF adults
The results indicate that PFF adults could be emerged from pupae buried in the sand soil of a depth of 40 cm. At 50cm adults failed to emerge. Statistical analysis proved negative correlation between the emerged flies and the column weight of sand over the pupae.
4- Relative preference of PFF to some fruit and vegetables under laboratory conditions
Thirteen species of the available fruit and vegetables were chosen for this study under the laboratory conditions using a new choice chamber. Statistical analysis of obtained data indicated that guava fruit was the most preferable host. According to an ascending sorted list of attraction percentages based on number of files attracted to guava. Lemon, zucchini, grapefruit and plum fruits were the least attractiveness, whereas, cantaloupe, apple and pear were found to be highly preferable fruits. The rest of examined fruits, peach, fig, mango, orange, and cucumber, had a moderate preferable level. This wide range of response in the present work may be attributed to the large number of volatile substances that emanate from fruit inducing insect responses.
Part II
Zizyphus Fruit Fly (ZFF):
1- Multi-correlation analysis between some vital aspects of ZFF and soil characteristics
Data of soil characteristics and the vital aspects of the zizyphus fruit fly were subjected to one way analysis of variance and multi-correlation analysis programs. The analysis of variance of the data indicates that each type of soil showed a different effect on the percentage of infestation and on the vital aspects of pupal stage of zizyphus fruit flies. The obtained data revealed that the effect of sandy, sand loamy and loamy soil types on the percentage of pupation were 32.2, 35, and 41%, respectively. The percentage of emerged adults was varied according to the soil type on which the fruits were fallen. It was 25.5, 33.2, and 65.8% related to sandy, sand loamy and loamy soil types, respectively. Pupal periods lasted for 16.4, 14.8, and 11.4days for sandy, sand loamy, and loamy soil types, respectively.
Simple and multiple correlations indicated that the percentage of sand, total soluble salts (TSS), and saturation capacity, are the key factors in the above-mentioned variations; although, the simple correlation between these variables were (not significant). In contrast, some factors with highly significant simple correlations; have the less co-efficient of determination. These reversed evidences, show that the simple correlation between a dependent factor and an independent one, is not enough to determine the relative efficiency of the independent factor where it has an auto-correlation with other independent factors.
2- Effect of soil type, moisture and sand cover on pupation depth, survival of pupae and adults
The current study indicated that the most suitable soil type and moisture level for the emergence of Zizyphus fruit fly (ZFF), Carpomyia incompleta Becker (Diptera: Tephritidae) was the sandy soil containing 15% water. It was found that the highest pupation depth was about 5cm. To avoid the harmful to the friendly soil fauna, it may be suggested that if the soil fumigation or gas producing materials must be applied, it should be penetrated into the soil not more than 10cm. The effect of soil depth on the survival of pupae and adults of ZFF was studied under laboratory conditions. The results indicated that, soil depth is negatively correlated with emergence of ZFF adults. The highest rates of fly’s emergence (100-80%) were observed at the lowest depths (1-15cm) with no significant differences in the percentage of adult emergence. In fact, we have recorded that highest rates of emergence (100 and 95%) were corresponded to 1and 2cm depth, respectively. The rates of emergence were gradually reduced when pupae placed on depth between 20 and 40cm. Rate of emergence at these depths was shown to be 70% at 20cm depth and 45% at 40cm depth. Depth of 50cm had detrimental effect on emergence of adult fly, where the flies failed completely to emerge from the pupae (0%) at this depth. The results showed also that depth of soil between 5 and 10cm is the most preferable for emergence of ZFF adults.
Our results are evidence that soil depth had a significant impact on emergence and survival of adults of ZFF. Therefore, we suggest that soil depth should be considered as one of the most important abiotic factors in minimizing the pest’s population.
3- Toxicity and persistence of Spinosad (Conserve 0.024% and Tracer 24%) To ZFF under laboratory, conditions
Two forms of the insecticide (Spinosad®) are recommended by the Egyptian Ministry of Agriculture and Reclaimed Areas for the control of the fruit flies. One form is for partial spray of fruit trees and one form is for soil treatment.
a) Conserve 0.024% application:
Statistical analysis indicated that the toxicity regression line had a linear order with a co-efficient of determination R2 = 0.779. The LC50 was determined by both mathematically and from the illustrated line as 95.17 ppm Persistent regression line was of the first order line with regression co-efficient of -16, simple correlation of 0.977 and co-efficient of determination of 0.9552. The T50 was found to be 2.2 days.
b) Tracer 24 % application:
Toxicity regression line has a linear order; the simple correlation was found to be 0.819; the Co-efficient of determination (R2) was found to be 0.6712. The LC50 was determined by both mathematically and from the illustrated line as 15.5 ppm.
Spinosad has a different mode of action from other pesticides and is most effective when applied in planned programs with other insecticides of different mode of action. Moreover, users must avoid use of same active ingredient or mode of action on consecutive generations of insect. However, repeated applications to control a single generation are acceptable. Thus we strongly recommend applying Spinosad as a soil application to control the last generation of the summer season.
4- Studies on the parasitoid Opius concolor associated with ZFF
The present study aims to show that Zizyphus trees must be preserved from exposure to pesticide applications for several reasons: They are trees with no economic values, and are the sole host plant of Zizyphus Fruit Fly (ZFF), Carpomyia incompleta, (monophagous species) add to that the pest (ZFF) is very sensitive to the associated parasitoid, Opius concolor. Therefore, the present experiment was carried out for two successive years, 2011 and 2012. In the first season of 2011, ZFF started to emerge at the first of April with 28% emergence, thereafter the fly emergence gradually increased to reach the maximal value (56%) by the end of May. In the second season of the same year the percentage of flies emergence started with 63.67% during September 11th, afterwards it increased to reach the maximal value (83.67%) by the end of September. Data indicated also that the overall males/females ratio of ZFF was 0.43 during the both years of study. The maximum parasitism was recorded in April 22nd (26.0%), meanwhile no individual parasitoid was observed during September. The fluctuation of ZFF in both years showed similar trend. The ratio between the parasitoid O. concolor and Zizyphus Fruit Fly in 2011 was similar to that of 2012 except that a low percentage of parasitism was observed at the beginning of September. Keeping in view the aim of the present investigation, as well as the obtained results, zizyphus tree from our point of view may become a host plant with highly economic importance where it acts as a natural resource or reservoir for one of the most effective parasitoid of fruit fly species without any economical cost. We also advise those working in the field of Horticulture, Pomology Departments to propagate and cultivate Zizyphus trees around fruit orchards to act as windbreaks besides their function as a source of parasitoid.
Thesis recommendations:
1- Trapping system consists of Abdel-Kawi trap baited with 0.5ml methyl eugenol must be used at dawn period (the first appearance of light in the morning followed by sunrise). This is because our results proved that PFF males had the highest activity at dawn period between 5 and 7a.m.
2- Traps must be hung from guava trees at one meter height because this height was shown to be the most suitable for capturing high numbers of PFF males.
3- Focus on pupal and adult stages in controlling process of fruit flies as these stages existed outside the fruits, while the other developmental stages are found inside the fruits, thus the use of pesticides spray for killing these stages becomes difficult and also to prevent poisoning when using sprayed fruits.
4- Collecting guava fruits before complete maturation because the present study proved that the maturity level of guava fruits was the most effective variable in attracting PFF males to methyl eugenol baited traps and had an effect on the average number of attracted males.
5- Several varieties of fruit should not be grown in one grove, particularly the most preferable fruit of PFF such as guava, cantaloupe, apple and pear, instead lemon, grapefruit and plum must be cultivated in areas with severe infestation as these fruits are less favourable for insect.
6- Researchers are requested not to rely on the simple correlation between one of the independent factors and a dependent factor to explain their data because this may give misleading results. In addition, simple correlation alone is not sufficient to determine the relative efficiency of the independent factor due to the presence of an auto correlation between this factor and the other independent factors acting on the same dependent factor.
7- The present study suggests that soil depth must be considered as a one of the important abiotic factors in minimizing fruit fly populations. This abiotic factor must be taken into consideration when buring infested fallen fruits in the soil, they must be covered with a layer of clay or clay sand soil with not less than 50cm.
8- If necessary to use Spinosad (Tracer 24%) as a soil treatment insecticide for controlling ZFF, we strongly recommend its use in the last generation of Summer season to avoid development of resistance to it when repeatedly used.
9- Zizyphus trees must be protected from insect attack as they act as a natural resource or reservoir for one of the most important parasitoid of fruit flies (Opius concolor) without any economical cost. Moreover, we also advice those working in the field of Horticulture, Pomology Departments to propagate and cultivate Zizyphus trees around fruit orchards as windbreaks in addition to their function as a source of parasitoid.
It may be concluded that the information given in the present study are of great value and can be used as a base for developing an integrated pest management program for controlling fruit flies in Upper Egypt.