مجلة الاطروحة العلمية المحكمة الاطروحه للنشر العلمي
تأثير التلقيح بعزلات محلية من بكتيريا التربة المصاحبة للجذور على نمو وامتصاص العناصر الغذائية لأشتال نبات الخشخاش
(Citrus aurantium L.)
د. سامر أحمد عزام ا. مشارك. د. جمال يوسف عياد
الجامعة الأردنية / كلية الزراعة/ قسم البستنة والمحاصيل
ا.مساعد. د. معاذ عبد اللطيف القيام
جامعة جرش/ كلية الزراعة / قسم الإنتاج النباتي والوقاية
ABSTRACT
Plant growth-promoting microorganisms have beneficial effects on plants and have been suggested a potential alternative to the use of chemical fertilizers. Microorganisms were isolated from the rhizosphere (SP) and rhizoplane (PL) of sour orange trees. Isolates were screened and characterized to end up with three bacterial (BSP12, BSP45, BPL64) isolates. Sour orange plants were inoculated with those 3 isolates in addition to the control seedlings that were not inoculated. were grown in 5 liter plastic pots under glass house conditions. Seedlings were subjected to 5 different nutrient solutions (distil water, full Hoagland solution (FHS), FHS minus nitrogen, FHS minus phosphorous and FHS minus iron). Results indicated that bacterial isolates were either gram positive (BSP12, BSP45) and or gram negative (BSP64) and they were identified as Bcillispp, Staphylococcus lentus and Serratia Plymuthica, respectively. Quantitative analysis of IAA revealed that all bacterial isolates were able to produce IAA in the culture medium. Positive growth stimulation was observed in plants inoculated with bacterial isolate BSP45 that exhibited taller vigorous and darker green plants. They also had the highest iron content and the highest level of IAA produced in culture media. Irrigating plants with different nutrient solutions affected significantly seedling fresh and dry weight and ion content. Deficiency of N and P resulted in reduced growth as compared with those in FHS and with those deficient in Fe. Root growth was also affected by inoculations were larger root system was observed in seedlings inoculated with bacterial isolate BSP45 even under P deficiency. Tissue nitrogen, phosphorous and iron content was also affected by inoculation and nutrient solution treatments. Seedlings inoculated with BSP45 had the highest N content with 18% increase over the control. Similar effect of inoculation with bacterial isolate BSP45 were observed on seedling Fe content. Inoculated seedlings were 16% higher in Fe content as compared with uninoculated ones. Results of this experiment indicated a positive growth promotion of BSP45 isolates .