الفهرس 
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Abstract
The present study was carried out in private orchard of citrus trees at Shenofa locality at Menoufia Governorate, for one year to study the occurrence of different pests and predacious of insects and mites associated with leaves of the four tested varieties: Citrus reticulate (Balady mandarin), Citrus sinensis var. Seefi (Valencia orange), C. sinensis var. Navel (seedless orange), C. sinensis var. Balady (Balady orange). Experiments lasted from January-December 2016).
The general outline of present study could be summarized in the following points:
1- Survey and population dynamics of phytophagous associated with citrus varieties.
2- Survey and population dynamics of phytophagous mites associated with citrus.
3- Population dynamics of fruit flies associated with citrus varieties.
4- Survey and population dynamics of predacious insects associated with citrus.
5- Survey and population dynamics of predacious mites associated with citrus.
6- Effect of different pesticides in the control of phytophagous mites under field conditions.
7- Effect of different pesticides in the control of phytophagous insects under field conditions.
The aim of study was to throw the light on phytophogous and predacious of insects and mites associated with citrus varieties of Shenofa locality, Menoufia Governorate.
I. Ecological studies :
1- Survey of insect pests attacking citrus orchards:
The collected insect pests from leaves of four citrus varieties, Balady mandarin, orange (Valencia) , orange (Naval) and orange (Balady), along one year were classified to seven species, which are : chrysomphalus aonidum, Aonidiella aurantii , Lepidosaphes beckii , Parlatoria ziziphi , Phylloenistis citrella , Ceratitis capitata , and Bactrocera zonata .
As for chrysomphalus aonidum, infesting Balady mandarin and Valencia orange, the results indicated that the highest population density was recorded in May and September months with average (1.66 and individuals/ 10 leaves). The lowest numbers of population density of C. aonidum were recorded at August month (1.0 indiv./10 leaves) on Naval and Balady orange.
As for Aonidiella aurantii, the results indicated that the highest numbers were recorded on Balady mandarin at May month (14.66 individuals/ 10 leaves), while on Valencia orange was recorded at June month (2.0 indiv./10 leaves), Naval orange at June and July months (3.0 indiv./10 leaves) and Balady Orange at August (3.0 indiv./10 leaves).
Regarding to Lepidosaphes beckii, results indicated that the highest record was (4.66 individuals/ 10 leaves) at June on Balady mandarin and at August month was (3.0 indiv./ 10 leaves) on Valencia orange, while the highest numbers were recorded on Naval orange at June & July months (3.0 indiv./ 10 leaves) and Balady orange at July with average numbers (4.66 indiv./ 10 leaves).
As for Parlatoria ziziphi, infesting Balady mandarin the highest numbers were recorded at July month (152.33 indiv./ 10 leaves), Valencia orange at August (10.66 indiv./ 10 leaves) and Naval & Balady orange at October were (8.33 indiv./ 10 leaves). Also, results indicated that there were lowest numbers for all species at December, January and February on all varieties of trees, except the insect of P. ziziphi was recorded the lowest numbers at January month (1.0 indiv./ 10 leaves).
As for Phylloenistis citrella, the results indicated that the average numbers were (6.33 indiv./10 leaves) at July month.
2- Predacious insects:
As for the predacious insects Lady bird, Coccinella spp. and chrysopa spp., the data reported that the highest numbers of the predatory insect, Coccinella spp. on Balady mandarine were (6.33 indiv./10 leaves) at August month, whereas the highest population density were recorded in all the rest varieties at November with mean (3.44 indiv./10 leaves), while all stages and eggs of the predatory insect disappeared at December, January, Febrauary, and June months for all varieties of trees.
The predatory insect, chrysopa spp, associated with Balady mandarine, data indicated that the highest numbers were (3.66 indiv./10 leaves) at September month, while the highest population was in all the rest varieties at Aprile with mean (2.56 indiv./10 leaves), the least numbers were recorded at November, December, January, February, and March months.
3- Fruit flies in citrus:
Fruit flies were counted using Jackson traps which were hanged on trees 2 meters of ground. Catched flies were counted weekly for one year from January to December 2016.
The results showed that there are the fluctuation in the Bactrocera zonata Ceratitis capitata during 2016, while the highest numbers of fruit flies were recorded at March, May, September and October, where the average numbers of male were 9.25, 9.25, 7.0 and 8.0 respectively, while no one was recorded at January, February, June, November and December months, where the highest population of peach fly was recorded at September and October with averaged 4.5 and 5.0 flies respectively, also no individuals were recorded at January, February, March, April, and December months.
4- Phytophagous and predacious mites:
Field surveys and population study were conducted from January-December 2016 in citrus orchards of Shenofa village (Shebein El-Koom District) at Menoufia Governorate, Egypt, to determine the species composition of phytophagous and predatory mites. Panonychus citri (McGregor), Eutetranychus orientalis (Klein) (Tetranychidae); Phyllocoptruta oleivora (Ashm.) (Eriophyidae); Brevipalpus californicus (Banks) (Tenuipalpidae) and Tydeus californicus (Banks) (Tydeidae) seemed to be the most common phytophagous species found in citrus orchards. Two predatory mite species of two families were also recorded of these, Amblyseius swirskii Athias-Henriot, (Phytoseiidae) and Agistemus exsertus González (Stigmaeidae) were found to be the most abundant predatory species inhabiting the leaves of the different citrus varieties. The population fluctuation of the phytophagous and predacous mites on different citrus varieties at Shenofa region during the study course varied according the infested citrus varieties and sampling dates reaching to the peak in most cases during August. Navel orange was be more infestation with Phyllocoptruta oleivora than the other varieties of citrus (290.31indivduals), while the highest number of Panonychus citrii and Brevipalpus californicus recorded (85.63 and 45.3 mite indivduals, respectively) on Balady mandarin. The obtained data indicated that the maximum & minimum temperature and relative humidity expressed as an insignificantly positive during 2016 season on the population of the mites, P. oleivora, E. orientalis, B. californicus, T, californicus, A. swirskii and A. exsertus, but high significantly difference was obtained between the population of the phytophagous mite, P. citri only.
5- Control experiments:
The control experiments were tested using five pesticides: Agnar 20%, Ortus Super 5%, Vertimek 1.8%, Challenger Super 24%, Sitrogard 15%, the efficacy of pesticides against phytophagous insects and mites indicated that there were toxic effect on these pests infesting citrus trees under field conditions, where the results of the reduction percentages in the numbers of insect pests after one month of spraying reached 89.54%, 81.99%, 99.41%, 82.52%, 98.81% respectively. Also, the mean of the reduction percentages of mite species after one month of spraying giving 88.65%, 92.60%, 89.98%, 100%, 84.3% 1%) respectively.