Egyptian Alfalfa Weevil (EAW) pose great danger in recent years of alfalfa cultivation areas in El-Farafra Oasis, New Valley governorate, a crop that has an important role in combating desertification in terms of soil stabilization and increase fertility in modern reclamation areas, the population density of damaging stages of the EAW, Hypera brunneipennis (Boh.) in standing Alfalfa was estimated by conducting periodic survey during two successive years. Aestivated weevils migrated from aestival shelter by the last week of November and its population attained the maximum by the third week of March. Larval stage appeared during first and second week of February 2016 and 2017 respectively and lasted until the start of May. Population size of developing adults was closely correlated with larval population. Peaks of larva and newly emerged weevils occurred on 3 st and 20 th March 2016 and came one and two weeks later in 2017. All weevils developed in summer were obliged to enter summer diapauses (aestivation) during mid-May the influence of prevailing high temperature and long days. The effect of weather factors viz: daily mean temperature, daily mean relative humidity and day-length on the population density of adult, abundance and summer diapauses was statistically discussed. This recent study proved that the insect had one generation in the field per year.

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In recent years the number of cabbage worm Pieris rapae has increased in Beni Suef Governorate, and they have threatened the vegetative growth of cabbage crop, especially in the newly reclaimed areas. That study was conducted during the 2017/18-2018/19 seasons respectively. Results obtained revealed that there are two distinct peaks for each eggs, larvae and pupae stages per year on cabbage plants. The immature stages covered the entire period of sampling from August 2017, till April 2018 on the cabbage plant. The first peak of egg Population was recorded on November 6 2017 and another smaller peak on mid of March 2018. The maximum larval Population (770 larvae) appeared on November 13, 2017 another smaller peak (450 larvae) on beginning April 2018. Pupal population exerted two periods of abundance On the 22 November, 2017 the highest numbers of pupae were recorded and another smaller peak on mid-April 2018. We can point out that the first and second peak of these stages in 2018/19 came about one to two weeks after the previous season 2017/18. The results also showed that there were statistically significant differences between the number of immature stages and the seasons of the year in cabbage fields. The cabbage sown in autumn season was severely attacked by this pest, followed by spring season. Autumn insect population was about 2-3 folds of winter population. Knowledge of the seasonal abundance of the immature stages is of great valuable to help in planning a control program against this target pest.

Extension of the newly reclaimed areas for agriculture in Egypt has obviously affected the microclimate of the insect pests, which seriously threatens the cultivated field crops. Besides, the role of the major natural enemies must be carefully understood. Therefore, a field study was conducted in El-Farafra Oasis, Western Desert, Egypt to assess biodiversity and population dynamics of major natural enemies found associated with three field crops (faba bean, cotton, and alfalfa) by sweep-net and beat and shake sampling. The species diversity of natural enemies included 27 species, 23 genera, 14 families belonging to six orders and the total abundance of these species was 5098 individuals sampled during 2018 and 2019. The most common insect order was Coleoptera (composing 42.2% of the total abundance) followed by Hymenoptera (28.1%) and Neuroptera (17.8%), whereas the smallest number of individuals found in Odonata (2.1%). Similar population dynamics of natural enemies in the three crop fields were observed during the two seasons, and most species showed a positive correlation with temperature and negative correlation with relative humidity. The values of species diversity, richness, and evenness indices were higher in the alfalfa field (2.529, 2.623, and 0.846, respectively). .

Opuntia ficus-indica is gaining scientists' and policy makers' interest worldwide as drought tolerant crop adopted to marginal low fertile soils. Few studies were conducted to estimate its water management parameters under different soil-climate conditions. O.ficus-indica was planted in the experimental farm of City of Scientific Research and Technological Applications (SRTA-City, Alexandria, Egypt) under different irrigation scheduling applications. The study aimed to understand the effect of severe water deficit on crop development and water management related parameters. First irrigation scheduling (T1) applied irrigation with fixed amount of water (7.2 m 3 ha -1 week -1 ). The second (T2), was applied when soil water content (SWC) became below 35% of field capacity (Ɵfc) in effective root zone. The third (T3), was conducted when SWC was below 30% of Ɵfc. The results revealed higher yield under T1 than T2 and T3. Water productivity was the lowest in T1 (0.62 kg m -3 ) and the highest in T3 (18.13 kg m -3 ). Actual crop evapotranspiration (ETa) was significantly higher in T3 (4.80 mm day -1 ), than T2 (4.56 mm day -1 ) and T1 (3.84 mm day -1 ). No significant difference was found in soil water content, canopy cover, crop coefficient among the applied irrigation scheduling. Average canopy cover was 13.63%, 11.08%, and 10.22% for T1, T2, and T3, respectively indicating early crop development stage. The corresponding crop coefficient (kc) was between 0.19 in T1 to 0.23 in T2 and 0.24 in T3. Further study is recommended to confirm obtained results and estimate ETa and kc under middle and end crop development stages.