الفهرس 
Acknowledgement
The cotton thrips, T. tabaciOnly 14 pages are availabe for public view
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Abstract
The present studies were undertaken for two vegetable crops (okra and squash) and their recommended traditional varieties. The considered pests in this study were: the cotton whitefly, B. tabaci (Genn.); the cotton aphid, A. gossypii (Glover); the green leafhopper, E. lybica Bergevin; the cotton thrips, T. tabaci L.; the green stink bug, N. viridula L.; the cotton seed bug, O. hyalinipennis (Costa) and the two-spotted spider mite, T. urticae Koch, in addition to their predators (viz., Coccinella undecimpunctata; Scymnus punctillum; Chyrsoperla carnea and chrysopa vulgaris). Hence, the work herein includes also an identification of certain predacious mite species extracted at a dept of 10 cm of the soil beneath plantations of okra and squash varieties.
Previous work reviewed, materials and methods were explained, then the results were analyzed, tabulated, illustrated, discussed and summarized. The dissertation was entailed with a general discussion. The results revealed the following topics:
1- Okra, A. esculentus L.
1.1. Survey of phytophagous pests and their associated predators inhabiting okra varieties:
1.1.1. Phytophagous pests:
The collected pest species in the present study were identified as 39 species pertaining to 7 orders (Orthoptera, Thysanoptera, Hemiptera-Heteroptera, Hemiptera-Homoptera, Diptera, Lepidoptera and Acari) and 15 families. Of these 21 species are considered as destructive species causing damage, 6 visitors and 12 beneficial arthropods were recorded.
1.2. Seasonal abundance of phytophagous pests and their associated predators inhabiting okra plants:
Most of the phytophagous pests on okra plants were appeared in the second work of May and increased in their numbers to reach the first peaks of incidence during the third week of June. The second population peaks of the phytophagous pests were recorded during the second fortnight of August, then a gradual descent in population changes were noticed from the last week of August till the second week of September. The same trend of occurrence was recorded for the associated predators.
1.3. Simultaneous effect of certain environmental factors on the population fluctuation of phytophagous pests and their associated predators inhabiting okra plants:
Climatic factors are the most important variable factors affecting on the survival, developmental and reproductive capacity of the insect pests and their associated predators.
On the other side, the plant age, temperature and relative humidity are considered to be a limiting factors and played the most important role in the population changes of the phytophagous pests (insects and mites), as well as for their predators.
1.4. The evaluation of the resistance of okra varieties against the phytophagous pests:
Eight okra varieties were evaluated in order to study their susceptibilities to certain arthropod pest. It can be concluded that, the lowest insect pest populations were recorded in Klemon sbenals variety followed by Oraby, Sabaa elst and Baldy. While, the highest ones were noticed in Askandrany and Lee. In contrary with this phenomenon, the varieties: Kna and Baldy recorded less mite populations. While, Lee and Askandrany exhibited the highest ones, Oraby, Klemon sbenals, Boza Swan and Sbaa elst were inbetween.
2. Squash, C. pepo L.:
2.1. Survey of phytophagous pests and their associated predators inhabiting squash plants:
In the present study, 35 arthropod species belonging to 29 families and 15 orders were surveyed. Of these 17 species are considered as destructive species causing damage, 7 visitors and 11 beneficial ones inhabiting squash plants at Assiut Governorate.
2.2. Seasonal abundance of phytophagous pests and their associated predators inhabiting squash plants:
The incidence of the phytophagous pests on squash plants started from the first week of March, then the population increased gradually during the second week of March, reached its peak of abundance at the last week of March.
Afterwards, population declined obviously, reached the lowest level during the third week of April. The population started again to build up during May and June and completely disappeared during the first fortnight of July. Then the population started to appear with scarce members and again, the population diminished till the end of the period.
The same trend of occurrence was also observed in case of the associated predators.
2.3. Simultaneous effect of certain environmental variable factors affecting on the population fluctuations of the phytophagous pests and their associated predators inhabiting squash varieties:
The present results revealed that the climatic factors were responsibled for 49.76% of the population changes of the phytophagous pests. While, the plant age also was considered as an important factor affecting the population changes of these pests.
2.4. Impact of squash varieties and sowing dates on the population size of phytophagous pests and their associated predators:
The present experiment was conducted in order to evaluate the susceptibility of four squash varieties (i.e., Askandrany (baldy); Mabrouka F1; Eskandarani (indya) and Haitk) against the infestation of the most common pests and their predators. It can be concluded that the Eskandarani (indya) variety recorded the least population nof the phytophagous insects, followed by Mabrouka F1 and Haitk. While, Askandrany (baldy) recorded the highest one. In contrary, Mabrouka F1 variety exhibited less population of the two-spotted spider mite and the moderate ones were recorded for Eskandrani (indya) and Haitk (B). The highest population of mite was recorded in variety of Askandrany (baldy).
2.5. Impact of sowing dates on the susceptibility of squash varieties to the phytophagous pest infestation:
All the four squash varieties were cultivated in three sowing dates (February 8th SD1, April 4th SD2 and June 22nd SD3). The results revealed that the third sowing date of (22nd June (SD3)) exhibited less population level of the phytophagous insects and their predators. While, the highest one was recorded in the first sowing date of (February 8th (SD1) and the second sowing date of (April 4th (SD2)) was inbetween.
On the other side, the two-spotted spider mite, T. urticae eggs and motile stages on all squash varieties took the same trend of infestation at all sowing dates.
3. Survey of certain predacious mite species extracted from the soil under okra and squash varieties:
Nine species of predaceous mites belonging to 7 families and 2 suborders were surveyed from the soil under plantations of okra and squash varieties. The surveyed species were: six species of Mesostigmata (viz., A. bilinear Nasr, 1978; L. zaheri Nasr, 1987; M. muscadomesticae Scopoli, 1772; a. badryi Yousef and El-Borollosy, 1985; N. barkeri Hughes, 1948 and R. tebeenus Hafez and Nasr, 1979) and three species of Oribatei (Oppia concolor Koch, 1877; Ephilomannia cylindrical Berlese, 1904 and Zygoribatula tritici El-Badry and Nasr, 1974).