Keanekaragaman Bakteri Endofit Daun Bawang Putih (Allium sativum L.) Terinfeksi Virus dengan Perlakuan Bio-Catharanthine berdasarkan Analisis Metabarcoding

Nimas Sukma Puspita, Dr. Aprilia Sufi Subiastuti, S.Si.

2026 | Skripsi | BIOLOGI

Bawang putih (Allium sativum L.) merupakan komoditas hortikultura yang rentan terhadap infeksi Potyvirus sehingga dapat menyebabkan penurunan produktivitas tanaman. Infeksi virus tidak hanya memengaruhi fisiologi tanaman, tetapi juga dapat mengubah struktur komunitas bakteri endofit tanaman. Bio-Catharanthine merupakan ekstrak Catharanthus roseus yang berpotensi menginduksi ketahanan tanaman terhadap cekaman biotik. Penelitian ini bertujuan untuk mengetahui pengaruh Bio-Catharanthine terhadap keragaman, komposisi, dan profil komunitas bakteri endofit pada daun bawang putih terinfeksi Potyvirus berdasarkan analisis metabarcoding. Penelitian dilakukan menggunakan sampel daun bawang putih terinfeksi Potyvirus dengan perlakuan Bio-Catharanthine. Analisis komunitas bakteri endofit dilakukan menggunakan pendekatan metabarcoding gen 16S rRNA berbasis Oxford Nanopore Technologies (ONT). Data hasil sekuensing dianalisis untuk menentukan indeks keanekaragaman alfa yang meliputi richness, indeks Shannon, dan indeks Simpson, serta analisis relative abundance  bakteri endofit pada berbagai tingkat taksonomi. Hasil penelitian menunjukkan bahwa komunitas bakteri endofit memiliki keanekaragaman sedang hingga tinggi dengan nilai richness 1083 ± 1048,57, indeks Shannon 6,66 ± 1, dan indeks Simpson 1 ± 0. Komunitas bakteri didominasi oleh filum Pseudomonadota dan Actinomycetota, famili dominan Caulobacteraceae, Xanthobacteraceae, dan Propionibacteriaceae, dengan genus dominan Cutibacterium, Roseateles, dan Bradyrhizobium. Keberadaan bakteri yang berpotensi sebagai plant growth-promoting bacteria (PGPB) menunjukkan bahwa mikrobioma endofit berpotensi mendukung pertumbuhan dan ketahanan tanaman. Perlakuan Bio-Catharanthine dapat memengaruhi komunitas bakteri endofit yang terbentuk pada daun bawang putih terinfeksi Potyvirus. 

Garlic (Allium sativum L.) is a horticultural crop that is susceptible to Potyvirus infection, which can lead to a decline in crop productivity. Viral infection not only affects plant physiology but can also alter the structure of the plant’s endophytic bacterial community. Bio-Catharanthine is an extract of Catharanthus roseus that has the potential to induce plant resistance to biotic stress. This study aimed to determine the effect of Bio-Catharanthine on the diversity, composition, and profile of the endophytic bacterial community in Potyvirus-infected garlic leaves based on metabarcoding analysis. The study was conducted using samples of Potyvirus-infected garlic leaves treated with Bio-Catharanthine. Analysis of the endophytic bacterial community was performed using a 16S rRNA metabarcoding approach based on Oxford Nanopore Technologies (ONT). The sequencing data were analyzed to determine alpha diversity indices, including species richness, the Shannon index, and the Simpson index, as well as to analyze the relative abundance of endophytic bacteria at various taxonomic levels. The results of the study indicate that the endophytic bacterial community exhibits moderate to high diversity, with a richness value of 1083 ± 1048.57, a Shannon index of 6.66 ± 1, and a Simpson index of 1 ± 0. The bacterial community was dominated by the phyla Pseudomonadota and Actinomycetota, with the dominant families being Caulobacteraceae, Xanthobacteraceae, and Propionibacteriaceae, and the dominant genera being Cutibacterium, Roseateles, and Bradyrhizobium. The presence of bacteria with the potential to act as plant growth-promoting bacteria (PGPB) indicates that the endophytic microbiome has the potential to support plant growth and resilience. Bio-Catharanthine treatment can influence the endophytic bacterial community that forms on garlic leaves infected with Potyvirus.

Kata Kunci : Allium sativum, bakteri endofit, Bio-Catharanthine, metabarcoding, Potyvirus