Electronic Theses and Dissertation

Rhizosfer bambu (Bambusa sp.) merupakan ekosistem tanah yang kaya akan aktivitas mikroba, termasuk cendawan entomopatogen yang berpotensi sebagai agens pengendali hayati terhadap hama tanaman. Pengendalian hayati menjadi salah satu strategi ramah lingkungan dalam menekan populasi Organisme Pengganggu Tanaman (OPT) tanpa menimbulkan dampak negatif seperti penggunaan pestisida kimia. Namun, informasi mengenai keberadaan cendawan entomopatogen pada rhizosfer bambu masih terbatas. Penelitian ini bertujuan untuk mengeksplorasi jenis-jenis cendawan entomopatogen yang terdapat pada rhizosfer bambu menggunakan umpan ulat hongkong (Tenebrio molitor). Penelitian dilakukan di Laboratorium Dasar Perlindungan Tanaman dan Laboratorium Ilmu Penyakit Tumbuhan Fakultas Pertanian Universitas Syiah Kuala, dengan metode pengambilan sampel tanah acak dari tiga lokasi: Desa Rukoh, Desa Kopelma Darussalam, dan Desa Cot Cut. Teknik eksplorasi menggunakan metode soil baiting dengan umpan ulat hongkong, diikuti dengan isolasi, pemurnian, serta identifikasi morfologis berdasarkan karakter makroskopis dan mikroskopis.
Hasil penelitian menunjukkan bahwa gejala infeksi cendawan entomopatogen pada larva ulat hongkong mulai tampak pada hari ke-8 setelah infestasi, ditandai dengan penurunan aktivitas, perubahan warna tubuh, dan munculnya miselium pada permukaan tubuh larva. Dari hasil isolasi diperoleh sepuluh isolat cendawan entomopatogen yang kemudian diidentifikasi menjadi dua genus utama, yaitu Aspergillus sp. dan Trichoderma sp. Kedua genus tersebut termasuk dalam divisi Ascomycota dan memiliki kemampuan menghasilkan enzim hidrolitik seperti kitinase, protease, dan lipase yang berperan dalam proses penetrasi dan infeksi kutikula serangga inang. Hasil ini menunjukkan bahwa rhizosfer bambu merupakan habitat potensial bagi keberadaan cendawan entomopatogen yang dapat dikembangkan sebagai agen pengendali hayati lokal. Penelitian lanjutan disarankan untuk menguji efektivitas kedua genus tersebut terhadap hama sasaran dan melakukan identifikasi molekuler guna memastikan spesies secara akurat sebagai dasar pengembangan teknologi pengendalian hayati yang ramah lingkungan.

The rhizosphere of bamboo (Bambusa sp.) is a soil ecosystem rich in microbial activity, including entomopathogenic fungi that have the potential to act as biological control agents against plant pests. Biological control is an environmentally friendly strategy for suppressing the population of Plant Pest Organisms (OPT) without causing negative impacts such as the use of chemical pesticides. However, information regarding the presence of entomopathogenic fungi in the bamboo rhizosphere is still limited. This study aims to explore the types of entomopathogenic fungi found in the bamboo rhizosphere using Hong Kong caterpillars (Tenebrio molitor) as bait. The study was conducted at the Basic Laboratory of Plant Protection and the Laboratory of Plant Disease Science, Faculty of Agriculture, Syiah Kuala University, using a random soil sampling method from three locations: Rukoh Village, Kopelma Darussalam Village, and Cot Cut Village. The exploration technique used the soil baiting method with Hong Kong caterpillars as bait, followed by isolation, purification, and morphological identification based on macroscopic and microscopic characters. The results of the study showed that symptoms of entomopathogenic fungal infection in Hong Kong caterpillar larvae began to appear on the 8th day after infestation, characterized by decreased activity, changes in body color, and the appearance of mycelium on the surface of the larvae's body. From the isolation results, ten isolates of entomopathogenic fungi were obtained which were then identified into two main genera, namely Aspergillus sp. and Trichoderma sp. Both genera are included in the Ascomycota division and have the ability to produce hydrolytic enzymes such as chitinase, protease, and lipase which play a role in the process of penetration and infection of the host insect cuticle. These results indicate that the bamboo rhizosphere is a potential habitat for the presence of entomopathogenic fungi that can be developed as local biological control agents. Further research is recommended to test the effectiveness of both genera against target pests and conduct molecular identification to accurately determine the species as a basis for developing environmentally friendly biological control technologies.