PENGARUH PERUBAHAN BAKTERIOMA-Beauveria bassiana PADA PATOGENISITASNYA TERHADAP Spodoptera exigua
Muhammad Ridho Illahi, Ir. Jaka Widada, M.P., Ph.D.; Dr. Ir. Ngadiman, M.Si.
2024 | Skripsi | MIKROBIOLOGI PERTANIAN
Pemanfaatan jamur entomopatogen Beauveria bassiana merupakan
salah satu pengendalian Spodoptera exigua yang ramah lingkungan. Selain
faktor lingkungan, viabilitas konidia, dan jenis hama, patogenitas jamur juga
dipengaruhi oleh interaksi jamur dan bakteri. Penelitian ini bertujuan
mengetahui pengaruh perubahan komposisi bakterioma terhadap morfologi dan patogenisitas
Beauveria bassiana dalam menginfeksi ulat bawang. Perubahan komposisi
dilakukan dengan penambahan antibakteri berupa kanamycin dan chloramphenicol
sebanyak 20 µg/ml pada media PDA. Perubahan bakterioma diamati melalui
identifikasi morfologi secara makroskopis dan mikroskopis serta analisis
molekuler dengan metode Ribosomal
Intergenic Spacer Analysis (RISA). Selanjutnya, dilakukan uji patogenisitas
Beauveria bassiana terhadap mortalitas Spodoptera exigua dengan
metode dipping pada suspensi konidia dengan konsentrasi 107
konidia/mL. Hasil penelitian menjukkan
bahwa pemberian antibakteri pada Beauveria bassiana mengakibatkan perlambatan
pertumbuhan serta perubahan warna koloni, dan tekstur. Perubahan bakterioma
akibat penambahan antibakteri ditunjukkan dengan adanya perubahan jumlah pita (band)
dan ukuran fragmen DNA. Perubahan tersebut meningkatkan patogenitas Beauveria
bassiana terhadap ulat bawang merah secara signifikan dalam kurun waktu 3
hari setelah penetrasi.
The utilization of the entomopathogenic fungus Beauveria
bassiana is a promising eco-friendly approach to control Spodoptera
exigua or beet armyworms. Besides environmental factors, conidial
viability, and host species, the pathogenicity of this fungus is also
influenced by its interaction with bacteria. This study aimed to investigate
the impact of altering the bacterial community on the morphology and
pathogenicity of B. bassiana in infecting beet armyworms. The bacterial
community was modified by adding 20 µg/mL of kanamycin and chloramphenicol
to potato dextrose agar (PDA) media. Changes in the bacterial community were
observed through macroscopic and microscopic morphological identification, as
well as molecular analysis using ribosomal intergenic spacer analysis
(RISA). Furthermore, the pathogenicity of B. bassiana against Spodoptera
exigua mortality was analyzed using the dipping method in a conidial
suspension at a concentration of 107 conidia/mL. Results showed that
the addition of antibiotics to B. bassiana cultures resulted in growth
retardation and alterations in colony color and texture. Changes in the
bacterial community due to the addition of antibiotics were indicated by
alterations in the number and size of DNA fragments. These changes
significantly increased the pathogenicity of B. bassiana against beet
armyworms within 3 days post-penetration
Kata Kunci : bacteriome, Beauveria bassiana, Spodoptera exigua, biocontrol.