المكافحة الأحيائية بالبكتريا Azotobacter chroococcum و المستخلص المائي لأزهار الدفلة لمرض التعفن الفیوزارمي في جذور النخيل

الملخص EN

Root rot disease of date-palm were found the as one of main cause inreduction of date –palm yield in the province of Dhi Qar \ Iraq .

Results of the field survey showed was conducted in 12 locations which the percentage of Root rot disease on date – palm reached 8.3 % to 45 % .

the Result of isolation from infected date – palm roots by root rot and identification of pathogen carried out the fungi : Fusarium solani ,F.nelsonii ,F.hostae ,F.beomiforme,F.begonia These fungus were recorded for the first time on date – palm in DhiQar.

Result of aqueuos extract of Oleander Flowers and bacteria A.chroococcum caused significant reduction in infection percentage severity by fungus F.

solani which induce 21.87 %-15.62 % Respectively in seventy days Date – palm seedling under lathe house condition campared with control (with out pathogen) and cause 81 .63 % infection severity .Result of the field experiment shows the aqueuos extract Oleander flowers and bacteria A.chroococcum and chemical pesticide( Beltanol) caused significant reduction in the percentage of infection severity by fungus F.solani which showed 15.16 %- 11.09 %- 8.33 % respectively on 3 years offshoot compared with control treatment with pathogen fungi only which was 85.66 % also all treatments indicated significant increase in all test plants growth average included the increase in the length of the off shoots and vegetative groups also the wet weight and dry weight and the high average offshoot and the ratio of the number of fronds in addition to increasing the number of newly formed roots.