نوع مقاله : مقاله پژوهشی
نویسندگان
1 مؤسسه تحقیقات جنگلها و مراتع، ص. پ. 116-13185، تهران
2 مؤسسه تحقیقات جنگلها و مراتع، ص. پ. 116-13185
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Decline and dieback is the most important diseases of eucalypt trees in Khuzestan province. In order to determine disease resistance of existing eucalyptus, four species and one provenance include Eucalyptus camaldulensis, E. camalulensis 9616, E. sargentii, E. microtheca and E. gillii, were evaluated using two different methods of “detached stems technique” and “seedling infection”. In detached stems technique, 8 branches (1 cm.diameter and 25 cm. length) from each species were selected and following surface sterilization with ethanol, five mm diameter bark disks were removed and inoculated centrally with a disk of agar carrying mycelium of highly virulent fungus obtained from diseased E. sargentii in Dobb-Hardan of Ahwaz. In the infection seedling method, 8 seedlings from each cited species were selected and wound-inoculated on stems. The rest procedures were the same as the previous technique. Each non-inoculated control plant received a P.D.A. disk. Wounds of two tests were covered with parafilm and sealed with adhesive tape. Eight replicate branches of each treatment were incubated at 35 ± 1 °C with R.H. 80 ± 5. At the end of two weeks of incubation period, the bark was removed and lesions on the cambium were examined, transferred to paper and their sizes were measured and analyzed.
Of the Eucalyptus trees evaluated in this study, E. sargentii and E. camaldulensis showed higher resistance than E. microtheca, E. gillii and E. camaldulensis 9616 in both methods mentioned. According to the results, resistance reaction of all species to N. mangiferae were the same in both methods. The most resistant species was E. sargentii while, E. camaldulensis 9616 was very susceptible species.
کلیدواژهها [English]
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