إبراهيم زيدان

الجامعة التكنولوجية · العراق

Adel Daikh, Boudjemâa Aichour

معهد الهندسة المعمارية والعمران-جامعة باتنة 1 - الحاج لخضر · الجزائر

Cherifa Touahri, Hayet Zoulikha , N. Chaher-Bzizi

كلية العلوم الطبيعية والحياتية-جامعة عبد الرحمان ميرة - بجاية · الجزائر

Amani Mohamed Khair Abbass, El Tigani El Tahir Ali

جامعة الخرطوم · السودان

A one year survey was carried out at two fields; Shambat and Elgeili to show the seasonal abundance of the Mediterranean fruit fly Ceratitis capitata (Weid.) on guava fruits, and adult emergence of the flies. A comparison between medfly infestation on orange and guava fruits was also investigated. The most susceptible fruiting stage of maturity to flies infestation was studied. In the laboratory a comparison between rearing the medfly stages inside orange and guava fruits, was carried out, also the effect of fermented fruits on the medfly larvae development. A study on the depth of pupation that constrain the medfly adult emergence, the effect of temperature, sunlight and heat, and water flooding on the medfly pupae was also investigated.This study revealed that the population abundance of the flies has two peaks, in autumn (August and September) and winter (January and February), and the lowest infestation was in the summer (May and June). The emergence of the adult was found to be regular all the year round, but the lower emergence percentages were in the summer. Infestation on guava fruits was found to be very high compared with that on orange fruits. Eggs and larvae of medfly development on guava took a shorter duration (2.24±0.31) and (4.0±0.74) days in average. A higher survival percentage (80.2%) and (77.17%,) was also noticed, compared to these developed on orange fruits (3.56±0.5) and (20.0±0.93) days duration for eggs and larvae, the survival percentages were (72.3%) and (64.1 %), respectively.Within the fruiting stages of maturity the ripe stage was found to be highly infested and was the most susceptible stage for flies infestation, followed by the mature and the immature stages. Fermentation of the fruits was found to enhance the development of the medfly larvae which took (3.05±0.7) days duration and (66.7%) survival percentage, while (3.7±1.78) and (8.0±1.3) days duration in gradually fermented and fresh fruits respectively. Chemical analysis of fresh and fermented guava resulted in high sugar content in the fresh fruits (4.06%) fructose, 2.52% glucose and 3.1% sucrose while they were all absent in the fermented fruits. However, (3.0%) ethanol was found in the fermented fruits. The most effective depth that constrained the medflies adults emergence was found to be more than 7.5 cm for all types of soil. When the medfly pupae were exposed to series of temperatures, the adults emergence was found to decrease with increase of temperature and 47°C gave zero emergence. The exposure of medfly pupae to direct sunlight and heat showed that the death of the pupae increased with increase in period of exposure, and the mortality rate was found to decrease with the increase of pupal age in the same period of exposure. The water flooding in the different types of soil was found to affect the medfly adult emergence, when hours of flooding were increased and it varied according to the soil type. Six hours exposure resulted in a significant reduction value of 27.2% of adult emergence in the silt soil, less than six hours in the clay soil and more than six hours in the mixed soil whereas more than 12 hours was needed in the sand soil to give the same effect. Flooding for 24 hr reduced the adult emergence percentage to less than 10% in all types of soil but 13.1 % in the sand soil.

حمزة نقارة, محمد صافة, موسى رقيق

كلية العلوم الاقتصادية، التجارية وعلوم التسيير-جامعة ابن خلدون – تيارت · الجزائر

تعتبر المؤسسات الناشئة محورا أساسيا في سياسة عمل الحكومة الجزائرية ، خاصة و أنها جزء من الوسائل التنمية الاقتصادية المستدامة التي يجب تعزيزها لكونها مستحدثة للثروة والمناصب الشغل، فحرصا من السلطات الجزائرية على دعم الطاقات الشبابية للمشاركة في بناء اقتصاد جديد من خلال دعم مشاركتهم ومرافقتهم لإنشاء المؤسسات المصغرة الناشئة الهادفة إلى تعزيز الاقتصاد الوطني، خاصة وأن الجزائر تتجه نحو اقتصاد قائم على الابتكار، يكون فيه العنصر البشري الأداة الأساسية الأولى لتطويره والرفع من مردوديته

أنس الشيخ محمد علي, دفع الله محمد عبدالوهاب, شمس الدين موسى أحمد

معهد إدارة المياه والري‎-جامعة الجزيرة-جامعة الجزيرة · السودان

The irrigated sector has vital contributions into food security and gross domestic product in Sudan. Among major problems, facing the irrigated sector is the sediment and aquatic weed removal. The most problematic aquatic weed in Sudan is water hyacinth, a native plant of South America that has been officially declared as an invasive pest since 1958. Water hyacinth forms dense plant mats, infested about 1700 km of the White Nile, from its upper reach near Juba to El-duim (70 km south of Khartoum) causing unenthusiastic collision on water intake channels. Its control measures depend initially on large-scale applications of chemicals. The main goal of this study was to investigate the impact of aquatic weeds on the performance of the irrigation network of the Kenana Sugar Scheme, White Nile State, Sudan, with special reference to the inlet channel of the pump stations. The specific objective of this study is to avert water hyacinth entering the inlet channel of the pump stations. Field and desktop datasets were collected for two seasons (2009/2010 and 2010/2011). The inlet channel was being divided into 5 cross- sections of 25 m in length per each. The water level was found to be 9% lesser the design one due to aquatic weeds. The results showed the detrimental impacts of aquatic weeds on the performance of the irrigation network, causing severe silt deposition and bank erosion and coupled with high maintenance cost of Kenana pumps stations. In the season 2010/2011, the cost of aquatic weed and sediment removal from the inlet channel, and all canals using mainly dredger, was found to be 1.856 million SDG, While the total cost of maintenance in Kenana pumps stations due the impact of aquatic weed is 0.357 million SDG coupled with civil work cost in Kenana inlet and canals due the impact of aquatic weed of 0.459 million SDG. The study recommended the need for fix suitable Tuff boom with debris screens permanently stretched across the intake channel for preventing the weed entering the inlet channel. Also, there is an urgent need for in-depth study on the impacts of weeds on the performance of the irrigation network.

بوجمـعة شتوان, ناغش عيدة

كلية الاداب واللغات-جامعة مولود معمري - تيزي وزو · الجزائر

Ali Oumhani , Naima Safa Khadraoui , Samia Belouadah

كلية الرياضيات والاعلام الآلي-جامعة محمد بوضياف - المسيلة · الجزائر

تمام خضر ياغي, عبد الناصر الضرير, فينـــــاي نانجيا

كلية الزراعة-جامعة حلب · سوريا

بنون خيرالله, حبيبة لرقط, رميساء دراسن

معهد العلوم الاقتصادية، التجارية وعلوم التسيير-المركز الجامعي عبد الحفيظ بو الصوف · الجزائر