The experiment was conducted through two successive seasons of 2008 and 2009 at ElBosaily farm, EI-Behira governorate at the North Coastal of the Nile Delta, in Egypt. This work aimed to study the effect of three green-house covers (polyethylene sheet, white and black net) and three irrigation levels [80%, 100% and 120% of the potential evapotranspiration estimated according to class A pan equation (ET,)], applied by drip irrigation system, on plant growth and crop yield of Cucumber (Cucumis sativus L.. cv. Reda F1). The experimental design was split- plot with three replicates. The results showed that white net green-house cover optimized growth and yield of cucumber plant. White net cover treatment recorded the highest vegetative growth (plant height, number of leaves, total leaves area, total fresh and dry weights), and significantly increased total yield. The highest vegetative growth was obtained by 100% ET, compared to 80 and 120% ETo treatments. The interaction among water treatment and green-house cover indicated the highest vegetative growth and crop yield were obtained under white net cover wi1th 100% ET0,.

The objectives of this study were to examine the relationship between wheat yield cultivars (Sakha 93 and Giza 168) and antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and phenylalanine ammonia-lyase (PAL) activities under different soil water content i.e. low, moderate and high content by Irrination at 806/6 ETo (1280m'/fed.), by, 100% ETo (1600m'/fed.) and120% ETo (1920m'/fed.), respectively. Two lysimeter experiments were carried out in two successive seasons i.e. 2006/2007 and 2007/2008 to estimate wheat yield and one experiment in plastic bags carried out of the greenhouse to determine the antioxidant enzymes of 28 days wheat plant under three different soil water content i.e. providIng wheat seedlings with aforementioned treatment. Exposing wheat cuitivars i.e. Giza 186 or Sakha 93 to water stress by Irrigation at 80% ETo (1280 m3/fad.) exerted an increase in CAT, SOD, POD, APX and PAL over those irrigated at 100% ETo (1600 m'/fad.) or at 120% ETo (1920 m'/fad.), but the previous enzyme activities in the tissue of Saka.93 surpassed of that of Giza 168 cuitivar. spike weight and weight of 100 grain/plant of Sakha 93 cuitivar overcome that of Giza 168 at low soil moisture content (80% ETo), whereas opposite results were obtained at high and moderate water content (120% and 100% ETo) in the first growing season (2006/2007) and spike weight/plant in second growing season (2007/2008). There was a proportional relationship between increasing soil moisture content and grain yield/plant but the difference between moderate water content 100% ETo (1600 m'/fed.) and high water content 120% ETo (1920 m3/fed.) was not significant. Providing 28 days wheat plant with low water content, decreased wheat yield/plant and its attributes comparing with moderate water content for the two studied cuitivars. The current study indicates that Sakha 93 cultivar was the most tolerant cuitivar compared with Giza 168.

Olive tree (Olea europaea L.) is one of the most important fruit trees, there is a lot of varieties with the possibility of mislabeling, homogenouses and synonyms, which makes major troubles when having plant material for propagation and breeding programs. In this search, 12 olive varieties (Maw! Istanbul!, Khilkhali Khishen, Dan, Mniekri, Adkam, Doaibli, Mot, Khilkhali Saghir, Karamani Modabal, Mawi abo Shokeh, Sourani, and Abo Shokeh), cultivated in ACSAD Gene bank in Gellin, were characterized by ISSR molecular markers to determine the relationship between these varieties. Depending on quantitive traits the results indicated that these varieties are so close to each other's, ranged from 60% and 85%. It was noticed that Mneikri was apart from the other varieties in its traits, (polymorphic rate was 92.94%).