tailieunhanh - Khả năng đối kháng của vi khuẩn nội sinh từ cỏ Mần Trầu với vi nấm gây bệnh thối ngọn cành trên thanh long (Hylocereus undatus)

Vi khuẩn nội sinh (VKNS) khu trú ở các khoảng gian bào trong các mô thực vật khác nhau mà không gây tổn thương. Nghiên cứu này nhằm tuyển chọn các chủng VKNS từ cỏ Mần Trầu (Eleusine indica) có khả năng đối kháng với vi nấm A. alternata gây bệnh thối ngọn cành (TNC) trên thanh long. | VNU Journal of Science Natural Sciences and Technology Vol. 37 No. 2 2021 60-69 Original Article Antagonic Activity of Endophytic Bacteria Isolated from Man Trau Grass on Stem Rot Disease Of Pitaya Hylocereus Undatus Do Quang Trung1 Nguyen Thi Thu Hang2 Dinh Mai Van2 Pham Bich Ngoc3 Tran Thi Hang2 Luu The Anh1 Phi Quyet Tien3 1 VNU University of Science 19 Le Thanh Tong Hoan Kiem Ha Noi. 2 Vietnam National University of Forestry Xuan Mai Chuong My Ha Noi. 3 Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Cau Giay Ha Noi Received 4 September 2020 Revised 15 April 2021 Accepted 24 June 2021 Abstract Endophytic bacteria reside in the intercellular spaces in different plant tissues without causing damage. This study aimed to select endophytic bacterial strains from Man Trau grass Eleusine indica that are able to inbibit the fungus A. alternata causing stem rot disease on pitaya. The result showed that one fungal isolate was pathogenic and caused stem rot disease on dragonfruit. The analysis results based on morphological characteristics and ITS region sequence indicated that the isolated fungal strain is 100 identical to A. alternata. In addition a total of 16 endophytic bacterial strains were isolated from Man Trau grass samples in Binh Thuan and screened for antifungal activity. Ten bacterial strains with antagonistic activity against A. alternata causing stem rot disease on pitaya were detected. Among those strain MT47 showed the strongest antifungal activity with an efficiency of . Moreover the result also presented that the antagonistic strain MT47 pocesses the ability of biofilm formation significantly higher than the control. The results suggest that these endophytic bacteria can be used in biocontrol of the stem rot disease on pitaya. Keywords Stem rot disease Hylocereus undatus Eleusine indica Alternaria alternata biofilm. _ Corresponding author. Email address trungcnsinh@ https 2588-1140 60 . Trung