ANALISIS KETAHANAN TANAMAN DUCKWEED (Lemna sp.) TERHADAP ANTIBIOTIK MELALUI INOKULASI BAKTERI PEMACU TUMBUH TANAMAN

Abstract

Senyawa antibiotik tidak dapat tercerna seluruhnya di dalam tubuh organisme sehingga akan diekskresikan dan dapat mencemari lingkungan. Meskipun sistem wastewater treatment plant (WWTP) telah berhasil mereduksi cemaran organik, tetapi mekanisme ini belum mampu menguraikan senyawa antibiotik sehingga diperlukan pendekatan biologis seperti fitoremediasi menggunakan tanaman akuatik duckweed (Lemna sp.). Pemanfaatan bakteri pemacu tumbuh dapat meningkatkan pertumbuhan dan perkembangan tanaman. Berbagai jenis bakteri simbiotik dapat hidup berdampingan dengan duckweed, namun, masih sedikit studi mengenai kapasitas bakteri dalam meningkatkan ketahanan duckweed terhadap antibiotik. Penelitian ini bertujuan melakukan karakterisasi isolat bakteri, menguji ketahanan duckweed dan isolat bakteri terhadap antibiotik, serta menguji kemampuan isolat bakteri dalam meningkatkan pertumbuhan sekaligus ketahanan duckweed terhadap antibiotik. Penelitian dilakukan di Laboratorium Genomik dan Lingkungan, Badan Riset dan Inovasi Nasional pada Januari-Juni 2025. Karakterisasi morfologi, sifat pemacu tumbuh, dan colony-forming traits (CFTs) bakteri telah dilakukan pada penelitian sebelumnya. Penelitian dilanjutkan dengan uji ketahanan bakteri dan duckweed serta ko-kultivasi keduanya pada cekaman antibiotik dengan hasil pertumbuhan bervariasi pada setiap perlakuannya. Ko-kultivasi duckweed bersama isolat bakteri dengan sifat pemacu tumbuh dan CFTs tinggi mampu meningkatkan jumlah fronds dan ketahanan terhadap antibiotik. Pemanfaatan duckweed dan bakteri pemacu tumbuh tanaman diharapkan dapat dikembangkan lebih lanjut pada sistem WWTP untuk limbah cair terkontaminasi antibiotik.

Antibiotic compounds cannot be completely digested by organisms, so they will be directly excreted to the environment. Although the wastewater treatment plant (WWTP) system has successfully reduced organic pollution, this mechanism has not been able to break down antibiotic compounds, which requires a biological approach such as phytoremediation using duckweed (Lemna sp.). The utilization of growth- promoting bacteria has enhanced plant growth, and various types of symbiotic bacteria are able to coexist with duckweed. However, there are still few studies on the capability of bacteria to increase duckweed's resistance to antibiotics. This study aims to characterize bacterial isolates, to evaluate the antibiotic resistance of duckweed and bacteria, and to evaluate the ability of bacteria to enhance duckweed's growth and resistance to antibiotics. The research was conducted at the National Research and Innovation Agency, from January-June 2025. The study began with characterization of the morphology, growth-promoting properties, and colony-forming traits (CFTs) of bacteria. Furthermore, bacterial and duckweed resistance tests were conducted, as well as co-cultivation of both under antibiotic stress, which showed various growth results in each treatment. Co-cultivation of duckweed with bacteria that possess growth- promoting traits and CFTs can increase the number of fronds and resistance to antibiotics. The utilization of duckweed and plant growth-promoting bacteria is expected to be further developed in WWTP systems for antibiotic-contaminated wastewater.