Clean-up of contaminated soils is a costly and slow process that requires long periods of time to be effective. Therefore direct use of contaminated sites with appropriate management is often likely to be a more efficient use of such land. Consequently, the production of safe animal forages from contaminated soils was the aim of this research. Field studies were conducted to evaluate the growth and elemental composition of river saltbush (Atriplex amnicola) grown on a metal-contaminated soil. The soil was amended with compost at rates of 0,15 and 30 t/ha to assess its role on plant growth and metal uptake. Compost application significantly (P0.05) increased biomass yield, crude protein (CP) and ash content of river saltbush; in contrast, it decreased the Zn and Pb concentrations in shoot tissues. When 30 t/ha of compost was added, the Pb concentrations in the stems and leaves decreased by 32 and 38% respectively. Despite the large total and extractable contest of metals in the studied soil, shoot concentrations of these metals in A. amnicala were always maintained below poteatially toxic levels. The biomass material of A. amnicala had a high nutritive value compared to conventional forage crops and could safely be used as animal forage. This work demonatrates that an Atriplex spp. A.amnicala, has significant potential for use as a safe forage crops in the sustainable on-site management of contaminated soils

There is little information available about the impact of nitrogen and phosphorus fertilization on the uptake of metals by Atriplex plants. A series of pots experiments were conducted to define the metals uptake response of four Atriplex species to urea (U) and superphosphate (SP) fertilization. The studied Atriplex species were river saltbush (A. amnicola), wavy saltbush (A. undulata), quail saltbush (A. lentiformis), and old man saltbush (A. nummularia). The growth and metals uptake of Atriplex species were significantly (P0.05) affected by the fertilizer treatments. U reduced the soil pH by 10% compared to the control. SP reduced the availability of Zn, Pb, and Cd by 24, 16, and 28% compared to the control. U increased the shoots Zn and Pb by 16 and 20% compared to SP. The combined application of U+SP reduced the Zn and Pb concentrations in the shoots by 10 and 13% compared to U alone. U increased the root-to-shoot transfer of Zn and Pb by about 30 and 49%. Root phosphorus (P) and calcium (Ca) limit the translocation of metals to the Atriplex shoots and this may be by the precipitation of the metals in the roots. The study clearly showed that it is feasible to apply P fertilizer to alleviate root-to-shoot transfer of Zn and Pb. Moreover, pure N application should be avoided to minimize the occurrence of high levels of Zn and Pb in the Atriplex shoots.

There is little information available about the impact of nitrogen and phosphorus fertilization on the uptake of metals by Atriplex plants. A series of pots experiments were conducted to define the metals uptake response of four Atriplex species to urea (U) and superphosphate (SP) fertilization. The studied Atriplex species were river saltbush (A. amnicola), wavy saltbush (A. undulata), quail saltbush (A. lentiformis), and old man saltbush (A. nummularia). The growth and metals uptake of Atriplex species were significantly (P0.05) affected by the fertilizer treatments. U reduced the soil pH by 10% compared to the control. SP reduced the availability of Zn, Pb, and Cd by 24, 16, and 28% compared to the control. U increased the shoots Zn and Pb by 16 and 20% compared to SP. The combined application of U+SP reduced the Zn and Pb concentrations in the shoots by 10 and 13% compared to U alone. U increased the root-to-shoot transfer of Zn and Pb by about 30 and 49%. Root phosphorus (P) and calcium (Ca) limit the translocation of metals to the Atriplex shoots and this may be by the precipitation of the metals in the roots. The study clearly showed that it is feasible to apply P fertilizer to alleviate root-to-shoot transfer of Zn and Pb. Moreover, pure N application should be avoided to minimize the occurrence of high levels of Zn and Pb in the Atriplex shoots.

Phosphorus (P) is an essential nutrient for the higher plants and has low mobility and availability in soils. Good fertilization management for this nutrient may be lead to increasing its availability. A field experiment in a split plot design was conducted out during the 2003 and 2004 summer growing seasons to study the effect of frequency of P fertigation and different forms of P fertilizers on uptake of P by corn plant as well as yield production. The high frequency of P fertigation increased P uptake significantly (p 0.05) by 12 and 19% in the first and second season respectively. Phosphoric acids (PA) followed by urea phosphate (UP) gave the highest significant biological yield (25.67 and 24.5 ton/ ha). From the results of this study, it may be recommended that in sandy calcareous soils P must be added every three days using acid forms.

In vitro as well as in vivo activities, it was investigated to examine if different botanical oils have any effects on the radial growth of A. solani and are able to reduce early blight incidence and severity in the field condition. Oils from various plant sources such as Jojoba (Simmondsia chinensis), Ginger (Zingiber officinale Roscoe), Garlic (Allium sativum), Clove (Syzygium aromaticum), Sesame (Sesamum indicum), Eucalyptus (Eucalyptus glabulus), Cinnamon (Cinnamon zylanicum) and Castor (Ricinu communis), lemon (Citrus limon) and mustard (Brassica nigra) were tested at concentration of 0.1%, 1% and 3% to determine their effects on the mycelial growth of A. solani. The 3% dosage of oil of ginger, lemon and castor inhibited the maximum radial growth of A. solani by 29.6%, 29% and 27% respectively. Meanwhile, the 1% concentration of lemon oil was also recorded the maximum growth inhibition of the pathogen by 27%. Moderate to lowest inhibition of the fungal growth was observed with cinnamon oil (21.6%) followed by oil of mustard (21.6%), jojoba (21%), sesame (21%) and garlic 20%. In vivo, at 1% concentration, the least disease incidence of 29.7% and 29.8% were achieved on plants treated with oil of garlic and lemon, respectively. Severity of early blight was significantly reduced by 34.9% of clove oil followed by 34.3% and 34.2% of eucalyptus and garlic, respectively. Fruit yield of tomato was totally increased with all oil treatment, clove oil significantly improved plant height and increased fruit yield by 58.3Kg/plot.

مما لاشك فیه أن موردي الأرض والماء یعدا من العناصر الأساسیة للإنتاج الزراعي ، فلا یمكن تصور وجود زراعة وإنتاج زراعي بدونهم ا ،لذا فان المشكلة الأساسیة لهذه الدراسة تكمن فیما لوحظ في الآونة الأخیرة وخصوصا بعد نجاح الشعب المصري في ثورتي ینایر 2010 ویونیه 2013 من حدوث تعدى على كل من الأرض الزراعیة ونهر النیل بالرغم مما تضمنته القوانین والتشریعات القانونیة من تجریم لهذا التعدي حیث زادت هاتین المشكلتین بشكل واضح وملموس وأثرتا على الاقتصاد القومي المصري بصفه عامة والزراعي على وجه الخصوص، لذا فانهذه الدراسة تهدف إلقاء الضوء على هاتین المشكلتین والتعرف على ملامحهم والأسباب التي أدت إلیهما كمحاوله لإیجاد الحلول المناسبة لتجنب أثارهما على الاقتصاد المصري، وقد اعتمدت الدراسة على استخدام الأسلوب الاستقرائي والتحلیلي لمجموعه من الحقائق والدراسات البحثیة الدراس المتعلقة بموضوع الدراسة.

Tomato (Solanum lycopersicum L.) production is severely affected by many diseases caused by many pathogens and among them viruses are the most serious pathogen. Begomoviruses causes yellow mosaic and leaf curl disease of tomato in the tropical, subtropical, temperate, and even semiarid regions. Yellow leaf curl disease is caused by Tomato yellow leaf curl virus belonging to the genus Begomovirus of the family Geminiviridae. In this study, naturally infected tomato leaf samples were collected during field survey and causal virus was identified by PCR using tomato yellow leaf curl virus-specific primers and transmitted by whiteflies to healthy tomato seedlings. The full-length viral genome was amplified by rolling circle amplification technology while betasatellites from viral genome were amplified by PCR using universal betasatellites primers. The full-length viral genome (~2.7kb) and betasatellites (~1.4kb) were cloned and sequenced bi-directionally. The generated sequences were assembled and analyzed to find out the genetic variability by using bioinformatics tools and the genetic variability and phylogenetic relationships with selected begomoviruses were analyzed. The complete viral genome sequences showed highest (99.5%) similarity with an isolate of Tomato Yellow leaf curl virus-Jizan 103 isolate and 92.8% similarity with Tomato Yellow leaf curl virus-Al-Qasim isolate while the lowest (71.6%) were found with Tomato Yellow leaf curl virus-Egypt isolate. The newly identified virus formed the closest cluster with Tomato yellow leaf curl virus isolates from Jizan and Al-Qasim, Saudi Arabia. On the basis of sequence similarity and phylogenetic relationship and recombination analysis, it is concluded that the virus causing tomato yellow leaf curl disease is a variant of tomato yellow leaf curl virus either from Jizan or Al-Qasim isolate circulating in the Kingdom of Saudi Arabia.

Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed.

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