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Field experiment was conducted at El-Fayoum Governorate during two successive seasons 2007and 2008 to study the population fluctuation of Brevicoryne brassice (Linnaeus) and Coccinella undecimpunctata L. and evaluation of C. undecimpunctata against B. brassice. Moreover, to evaluate the effect of certain weather factors (daily mean temperature, daily mean R.H.) on the pest and predator on Dill plant. The obtained data revealed that, the mean number of aphid species individuals began to appear on January and population increased to reach the maximum average on April during 2007 season. In the second season, the infestation of the individuals started to appear at the last week of December The mean number increased gradually to record two highly peaks on March and April The correlation between population fluctuation of aphid species and means of weekly (max., min. and mean Temps.) was positive and significant during 2006/2007 and 2007/2008 seasons. In addition, the correlation between insect infestation and mean of relative humidity was negative significant correlation during 2006/2007 and 2007/2008 seasons. Generally, mean of the total number of C. undicempunctata was higher in the second season than the first one. Releasing of C. undecimpunctata at rate 6 adult/ 2 m 2 gave the best reduction of aphid individuals recording general mean reduction percentage 93.14%. Followed by the second level (4 adult / 2 m 2 ) this suppressed the population by 85.62% and the low level (2 adult / 2 m2) with 81.86%, respectively.

Field experiment was conducted at Qualubia Governorate during two successive seasons 2006and 2008 to study the population fluctuation of Earias insulana on two Okra varieties. In addition, to study the effect of certain weather factors (daily mean temperature, daily mean R.H.) and plant age on the two Okra cultivars during two seasons. The obtained results showed that: the number mean of E. insulana started to occur on July27 th and increased gradually reaching the peak in September 14 th or plant age (163 days from sawing). The high number of larvae was recorded (7.8 & 6.3 larvae/10pods and 7.7 &6.8larvae/10pods) during the first and second seasons on the Okra varieties (Eskandarani and Balady), respectively. The weather factors (mean Temp. and plant age) had significant effect on population of E. insulana larvae with two varieties (Eskandarani and Balady) also the relative humidity had negative significant effect on population of E. insulana during two successive seasons 2006 and 2007 on two cultivars, respectively. The percentage of variance explained by three tested factors during two seasons, was 52.6&52.0 % and (89.7 and 95.4%) for the two Okra varieties, (Eskandarani and Balady), during two seasons respectively. Balady variety gave the highest yield, then Eskandarani variety during two seasons respectively. Phosphorus (gm/plant) was determined colorimetrically according to the method of Murphy and Riely (1962) as modified by John (1970). Potassium (gm/plant) was determined flame photometrically as mentioned by Brown and Lilleland (1946). Yield components:At the end of each season, the weight of pods per feddan for each variety was calculated. Statistical analysis:To get idea about the effects of plant age, climatic factors and its correlation with the insects, simple correlation and partial regression were carried out by using a computer software package, "Costat" a product of