Isolasi, Seleksi, dan Identifikasi Bakteri Endofit sebagai Agens Penginduksi Ketahanan Padi terhadap Hawar Daun Bakteri

Abstract

Bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae is one of the major problems in rice production in Indonesia. One of the control measures for the disease is by the utilization of endophytic bacteria. This study was aimed to determine the ability of endophytic bacteria isolated from the roots, stems and leaves of rice in inducing plant resistance to bacterial leaf blight on rice. Screening of endophytic bacteria showed that 370 isolates have good viability and have different colony morphology. Among them, 7 isolates were able to induce resistance and 1 isolate was able to promote the growth of rice in the nursery. However, only 8 isolates did not cause hypersensitive reaction on tobacco plants. The selected isolates of endophytic bacteria were further examined for their ability to induce resistance of rice in greenhouse experiments. Observation involved several variables, i.e. PR1 and PBZ1 gene expression, peroxidase enzyme activity, incubation period, and disease progression. Seven isolates of endophytic bacteria were able to induce PR1 and PBZ1 gene expression, 4 isolates were able to increase peroxide enzyme activity, 4 isolates could prolong the incubation period, and 2 isolates can inhibit the development of disease. However, only EB4 451 isolate was consistently able to induce PR1 and PBZ1 gene expression, increased peroxide enzyme activity, prolonged incubation period, and suppressed the progression of the disease. The EB4 451 isolate was identified based on nucleotide sequence as Bacillus subtilis.

Character Diversity of Black Rot Bacterial Strains (Xanthomonas campestris pv. campestris) on Cabbage against Mixture of Active Ingredients Azoxystrobin and Diphenoconazole

“…Inokulasi bakteri dilakukan dengan cara clipmethod, yakni menggunting atau memotong pinggir daun kubis sekitar 5 cm dengan gunting yang telah dicelupkan dalam suspensi bakteri X. campestris pv. campestris (Parida 2016). Isolat yang menimbulkan gejala pada daun kubis setelah 7 hari inokulasi digunakan untuk pengujian selanjutnya.…”

Karakterisasi Bakteri Endofit Tanaman Sirih Timor (Piper betle L.) Penghasil Antibakteri

“…Berdasarkan kemajuan bioteknologi saat ini, mikroba endofit pada tanaman obat dimanfaatkan sebagai sarana produksi antibiotik (Sepriana et al, 2017;Setianah et al, 2021) untuk keperluan obat dan farmasi, dan sarana transgenik gen-gen ketahanan tanaman (Parida et al, 2017) Antibiotik merupakan zat kimiawi yang dihasilkan oleh organisme seperti bakteri dan jamur, yang dapat mengganggu mikroorganisme lain. Antibiotik diketahui mempunyai spektrum luas mampu membunuh bakteri gram positif dan gram negatif, sedangkan antibiotik berspektrum sempit hanya dapat membunuh bakteri gram negatif.…”

Isolasi dan Seleksi Cendawan Rhizosfer dan Endofit asal Tanaman Kelor sebagai Agens Penginduksi Perkecambahan pada Benih Padi

“…Cendawan endofit dan rhizosfer diketahui merupakan salah satu jenis mikrob fungsional yang mampu memproduksi metabolit sekunder, yang secara langsung atau tidak langsung dapat memengaruhi pertumbuhan inangnya (Agusta 2009;Mirsam et al 2015) Pemanfaatan mikroba rhizosfer dan endofit dalam mengendalikan beberapa jenis patogen tanaman dan pengaruhnya terhadap tingkat toleransi tanaman telah banyak diteliti, baik dari golongan bakteri maupun cendawan (Damayanti 2013;Singh et al 2013;Mirsam et al 2015;. Beberapa penelitian melaporkan bahwa agens hayati mampu menekan pertumbuhan patogen dengan cara menginduksi ketahanan dan mendukung kebugaran tanaman padi (Rustam 2011;Kurniawati et al 2016;Nurfadillah 2016;Parida et al 2017;Dewi et al 2020). Namun, informasi mengenai pemanfataan cendawan rhizosfer dan endofit dalam menginduksi perkecambahan benih padi belum banyak dilaporkan.…”