Abstract. Wiratno, Syakir M, Sucipto I, Pradana AP. 2019. Isolation and characterization of endophytic bacteria from roots of Piper nigrum and their activities against Fusarium oxysporum and Meloidogyne incognita. Biodiversitas 20: 682-687. The endophytic bacteria from spices plants have potential as biocontrol agents. Nevertheless, their potential has not been explored. Pepper plant (Piper nigrum L.) is linked with promising endophytic bacteria as biocontrol agents. This study aimed to obtain isolates of endophytic bacteria from root tissues of pepper plant. The isolation of endophytic bacteria was done using surface-sterilization method and using Tryptone Soya Agar (TSA) medium. The result showed that 10 endophytic bacteria were successfully isolated. We found that a total of 9 bacteria were safe for plants and mammals and used for subsequent steps. The selected bacteria showed inhibition activity of Fusarium oxysporum (18.6 to 43.7%). Furthermore, the secondary metabolites of the endophytic bacteria also promoted lethal effects on Meloidogyne incognita (16.6 to 65.8%). The physiological activity also showed that seven isolates were able to produce chitinase, and four (4) isolates were able to produce protease. Additionally, 55.6% of isolates were also able to dissolve phosphorus and fix nitrogen. This study provided fundamental information related to the biocontrol properties of endophytic bacteria isolated from pepper plant roots.

Penyakit blas (Pyricularia oryzae) di Indonesia awalnya hanya merusak tanaman padi gogo, namun penyakit blas dilaporkan terjadi pada tanaman padi sawah sejak tahun 2000-an. Aplikasi cendawan endofit merupakan salah satu cara pengendalian yang berpotensi besar untuk dikembangkan. Penelitian ini bertujuan untuk mendapatkan cendawan endofit dari padi sawah yang berpotensi menekan keparahan penyakit blas. Isolasi cendawan endofit dilakukan dari bagian akar, batang, dan daun tanaman padi sawah. Varietas Kencana Bali digunakan pada pengujian penghambatan P. oryzae secara in vivo karena varietas tersebut merupakan varietas paling rentan terhadap penyakit blas. Sebanyak 47 isolat cendawan endofit berhasil diisolasi dari tanaman padi sawah asal Bogor, Sukabumi, dan Blitar. Berdasarkan morfologi koloni cendawan endofit dapat dibedakan menjadi 9 morfotipe. Sebanyak 4 dari 14 cendawan endofit menunjukkan aktivitas antibiosis pada pengujian penghambatan P. oryzae secara in vitro. Hasil pengujian penghambatan penyakit blas pada varietas Kencana Bali di rumah kaca menunjukkan bahwa 4 isolat tersebut mampu menekan perkembangan penyakit blas dengan tingkat penekanan antara 30-70%.

Sejumlah sampah organik yang dihasilkan sebagian besar masih belum dikelola dengan baik sehingga dapat berdampak buruk terhadap lingkungan. Teknologi paling mudah yang dapat digunakan untuk memanfaatkan sampah organik adalah pengomposan. Salah satu agen serangga yang saat ini popular dan dapat digunakan sebagai dekomposer limbah organik adalah larva Black Soldier Fly (Hermetia Illucent). Penelitian ini bertujuan untuk menganalisis mutu hasil biokonversi limbah organik sayur dan ampas tahu dengan menggunakan larva BSF. Parameter yang diuji yaitu derajat keasaman (pH), kadar air (KA), nitrogen (N), fosfor (P), rasio C/N, dan kalium (K). Hasil pengujian menunjukkan bahwa limbah organik ampas tahu dan limbah sayur yang telah dibiokonversi dengan menggunakan larva BSF selama 15 hari menghasilkan nilai N, P, K, C/N, pH, dan KA yang sesuai dengan persyaratan SNI 19-7030-2004 tentang Spesifikasi kompos dari sampah organik domestik. Sehingga dapat disimpulkan bahwa larva BSF mampu mendekomposisi limbah organik dengan cepat dan menghasilkan pupuk organik yang bermanfaat bagi tanah, tanaman dan lingkungan.

Xanthomonas oryzae pv. oryzae (Xoo) is one of the important diseases in rice. The key to Xoo's primary control is using disease-free or treated seeds and crop rotation. However, the relevance of using certified seeds or seedlings will be reduced if there is a combination of main pest attacks that help the entry of these pathogens into the plant, one example is the golden snail from the mollusca group. Based on several research sources, the mollusca group in marine areas is an untapped source and can be used to find new ingredients as antimicrobials. Starting from this, it can be seen that one of the important pests in rice, namely golden snails (Pomacea canaliculata), is part of the mollusca phylum which can actually be used as an antimicrobial. Given that P. canaliculata is one of the important pests in rice which is very destructive, this can be one of the advantages, namely that the pest will not return to the pest status but will also hold the status as an antimicrobial raw material used in rice plants as well. This is an innovation in itself in the field of controlling bacterial leaf blight because in addition to controlling the disease, the important pests of golden snails can be controlled. Chitosan and Antimicrobial Peptides (AMPs) were obtained by extracting golden snails using different techniques. A total of eight treatments were used in this study, namely negative control (KON), positive control (KKT), Chitosan (KT) with 3 concentrations, namely 0.2%, 0.4%, 0.6 and Antimicrobial Peptides (AA) with 3 concentrations. 1%, 3%, 5%. The method used is the paper disc diffusion method to determine the inhibitory power of Chitosan and Antimicrobial Peptides (AMPs) against pathogenic bacteria. Treatments that have an effect will be further tested using the Duncan test at the level of α = 0.05. Each chitosan and AMPs treatment at each concentration showed a different level of inhibition. The highest inhibition was seen in the AMPs treatment with a concentration of 1%. It was noted that the increase in concentration was inversely related to the inhibitory power in each treatment. The conclusion from this study is that chitosan and AMPs treatment has excellent potential as environmentally friendly antibacterials with abundant raw materials as indicated by the best treatment, namely AMPs 1%. The increasing number of new research related to environmentally friendly antibacterials will be a turning point in the world of antimicrobial development.

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