[Effect of mixed infection with Ascochyta rabiei and Alfalfa mosaic virus on The yield component of Chickpea plant]

Tobacco plant is one of the important strategical and Economical cereals for farmers in mor 100 countries . In Syria , Tobacco is located in thired degree of artificial cereals , because of the large number of workers whos are working in Tobacco's culture industrial and marketing . Many sub cultivars of tobacco are culturing in Syria , but because of the changbles in clhmatic condition , the quality and quantity are also changeful . So this research was carried out in the tow seasons 2007 and 2008 in Keniari vellage of Jablla area by the combined between cereals dep., of Agri., Fac ., in Tishreen Univ., and general organization of tobacco . This search aims to detrrmine the affected of plant gensity and topping on the quantitative and qualtitative triats of Job Hassan cultivar , which is Polgaric C.V. but , it's acclimated under Syrian cost area condition . In this research , four levels of plant density (14,18,22 and 26 plant \\m2)and three treatments of topping ( without cutting , early cutting , lated cutting) were studied in 4 replecates according to randomized bloak design . Morever for arrival to the search's aims many stadies are carried out as ( leaves number\\ plant, leafe area , total leaves area\\plant , green leaves production \\plant(g) and green leaves production \\donom (kg) ), In addition plant dry trias as (plant production (g) ,area production (kg) , materiality, thickness and absorption ).Also we were studied the sensuality and testing proparties like (flaver ,smell ,physiological force ) and chemical contents as(Nicotine , protein and sugars) . The results showed the followings: 1-The density (A 14plant \\m2) was gaved the highest values ofplant high , leaves number \\plant , green leaf area and green leaves production \\plant . 2-The ighest values of green leaves production and dry leave production \\Donom were obtained by the density tretmant (C 22plant \\m2) 3-the quantitative of leaves as (Protein Nicotine and sugars contents )were higatively affected by the low plant density . 4-the topping caused positive significant effects on all plant growth traits.