Eksplorasi Bakteri Endofit Akar Tanaman Tanduk Rusa (Platycerium grande (A.Cunn. ex Hook.) J.Sm.) dan Potensinya sebagai Plant Growth Promoting Bacteria (PGPB).

Wiyaniputri Hasna, Anggi (2025) Eksplorasi Bakteri Endofit Akar Tanaman Tanduk Rusa (Platycerium grande (A.Cunn. ex Hook.) J.Sm.) dan Potensinya sebagai Plant Growth Promoting Bacteria (PGPB). Sarjana thesis, Universitas Brawijaya.

Abstract

Bakteri endofit memiliki hubungan simbiosis dengan tanaman inangnya dalam memantu pertumbuhan tanaman dan sebagai agen biokontrol alami. Bakteri endofit tidak hanya meningkatkan pertumbuhan tanaman tetapi juga meningkatkan ketahanan terhadap berbagai jenis cekaman lingkungan termasuk suhu, pH, kekeringan, salinitas, dan infeksi patogen. Salah satu spesies tumbuhan epifit yang memiliki toleransi ketahanan tersebut adalah tumbuhan tanduk rusa Platycerium grande. Respon ketahanan tersebut tidak hanya bergantung pada faktor genetik dan lingkungan, tetapi juga dipengaruhi oleh keberadaan bakteri endofit yang hidup di dalam jaringan tanaman. Meskipun terdapat beberapa penelitian awal, namun masih terdapat kesenjangan tentang peran bakteri endofit pada tanaman Platycerium sebagai PGPB. Oleh karena itu, penelitian ini bertujuan untuk mengeksplorasi bakteri endofit asal Platycerium grande dan potensinya sebagai Plant Growth Promoting Bacteria (PGPB). Penelitian ini dilaksanakan mulai Agustus hingga Desember 2024 di kebun Lily Harvest dan Laboratorium Penyakit Tumbuhan 1 Fakultas Pertanian Universitas Brawijaya. Penelitian ini dilakukan dengan beberapa pengamatan dan pengujian. Pengamatan yang dilakukan meliputi karakteristik makroskopis dan mikroskopis koloni, serta keanekaragaman, dominansi, dan keseraragaman koloni. Sealin itu juga dilakukan beberapa uji antara lain uji hipersensitif, uji antagonis, uji morfologi mikroskopis, uji aktivitas biologis, uji cekaman, dan uji potensi IAA. Data yang telah diperoleh selanjutnya dianalisis secara kualitatif dan kuantitatif. Hasil eksplorasi memperoleh 21 isolat bakteri endofit akar P. grande dengan karakteristik morfologi yang berbeda. Kelimpahan tertinggi terdapat kode isolat PG1 dengan nilai TPC sebesar 4,8 × 106CFU/mL, sedangkan kelimpahan terendah terdapat pada kode isolat PG19 dengan nilai TPC 6,1 × 100 CFU/mL. Indeks keanekaragaman (H’) berbanding lurus dengan indeks keseragaman (E), sedangkan indeks dominansi (D) berbanding terbalik dengan indeks keanekaragaman (H’) dan indeks keseragaman (E). Hasil pengujian hipersensitif diperoleh 20 isolat bakteri tidak menunjukan gejala nekrosis, sedangkan 1 isolat menunjukkan gejala nekrosis yaitu kode isolat PG 13. Hasil uji antagonis dari 20 isolat bakteri menunjukkan bahwa hanya terdapat 6 bakteri yang memiliki aktivitas penghambatan. Pengamatan mikroskopis diperoleh bentuk bakteri terdiri dari Bacilli dan Coccus. Hasil uji gram diperoleh 1 isolat bakteri memiliki gram negatif dan 5 isolat bakteri memiliki gram positif. Isolat bakteri gram negatif dilanjutkan dengan uji anaerob mendapatkan hasil positif aerob dan anaerob. Isolat bakteri gram positif dilanjutkan dengan uji pewarnaan endospora, namun tidak didapatkan isolat yang memiliki endospora. Hasil uji cekaman suhu menunjukkan bahwa keenam isolat mampu tumbuh pada cekaman suhu 40℃ dan 50℃, namun tidak mampu tumbuh pada suhu 60℃. Pada cekaman pH keenam isolat bakteri mampu tumbuh pada pH 5 dan 6, namun tidak mampu tumbuh pada pH 4. Berdasarkan uji cekaman kekeringan, keenam isolat bakteri mampu tumbuh pada cekaman kekeringan 5% dan 10%. Selain itu, keenam isolat bakteri mampu tumbuh pada cekaman salinitas 5%. Hasil uji potensi IAA menunjukkan bahwa dari 6 isolat bakteri hanya 1 isolat bakteri yang memiliki potensi IAA. Hasil uji aktivitas PGPB menunjukkan adanya kemampuan keenam isolat bakteri dalam melarutkan fosfat dan menambat nitrogen. Berdasarkan hasil penelitian, diperoleh isolat bakteri endofit terbaik dengan potensinya sebagai PGPB adalah isolat dengan kode PG 7.

English Abstract

Endophytic bacteria have a symbiotic relationship with their host plants in aiding plant growth and as natural biocontrol agents. Endophytic bacteria not only enhance plant growth but also increase resistance to various types of environmental stresses including temperature, pH, drought, salinity, and pathogen infection. One of the epiphytic plant species that has such resistance tolerance is the deer antler plant Platycerium grande. The resistance response not only depends on genetic and environmental factors, but is also influenced by the presence of endophytic bacteria that live in plant tissues. Although there are some initial studies, there are still gaps about the role of endophytic bacteria in Platycerium plants as PGPB. Therefore, this study aims to explore endophytic bacteria from Platycerium grande and their potential as Plant Growth Promoting Bacteria (PGPB). This research was conducted from August to December 2024 in Lily Harvest garden and Plant Disease Laboratory 1, Faculty of Agriculture, Universitas Brawijaya. This research was conducted with several observations and tests. Observations made include macroscopic and microscopic characteristics of colonies, as well as diversity, dominance, and uniformity of colonies. In addition, several tests were also carried out including hypersensitivity test, antagonist test, microscopic morphology test, biological activity test, stress test, and IAA potential test. The data obtained were then analyzed qualitatively and quantitatively. The exploration results obtained 21 isolates of P. grande root endophytic bacteria with different morphological characteristics. The highest abundance was isolate code PG1 with a TPC value of 4,8 × 106 CFU/mL, while the lowest abundance was isolate code PG19 with a TPC value of 6,1 × 100 CFU/mL. The diversity index (H') is directly proportional to the uniformity index (E), while the dominance index (D) is inversely proportional to the diversity index (H') and uniformity index (E). The results of hypersensitive testing obtained 20 bacterial isolates did not show symptoms of necrosis, while 1 isolate showed symptoms of necrosis, namely isolate code PG 13. The results of the antagonist test of 20 bacterial isolates showed that there were only 6 bacteria that had inhibitory activity. Microscopic observations obtained bacterial form consists of Bacilli and Coccus. Gram test results obtained 1 bacterial isolate has gram negative and 5 bacterial isolates have gram positive. Gram-negative bacterial isolates are followed by anaerobic tests to get positive results for aerobes and anaerobes. Gram-positive bacterial isolates are continued with the endospore staining test, but no isolates are found to have endospores. The results of the temperature stress test showed that the six isolates were able to grow at 40℃ and 50℃, but were unable to grow at 60℃. In pH stress, the six bacterial isolates were able to grow at pH 5 and 6, but were unable to grow at pH 4. Based on the drought stress test, the six bacterial isolates were able to grow at 5% and 10% drought stress. In addition, the six bacterial isolates were able to grow under 5% salinity stress. The results of the IAA potential test showed that of the 6 bacterial isolates, only 1 bacterial isolate had IAA potential. PGPB activity test results showed the ability of the six bacterial isolates in dissolving phosphate and fixing nitrogen. Based on the results of the study, the best endophytic bacterial isolate with potential as PGPB is isolate with code PG 7.

Item Type:	Thesis (Sarjana)
Identification Number:	052504
Divisions:	Fakultas Pertanian > Hama dan Penyakit Tanaman
Depositing User:	Annisti Nurul F
Date Deposited:	14 Jan 2025 08:37
Last Modified:	14 Jan 2025 08:37
URI:	http://repository.ub.ac.id/id/eprint/234804

Text (DALAM MASA EMBARGO) ANGGI WIYANIPUTRI HASNA.pdf Restricted to Registered users only Download (3MB)

Actions (login required)

View Item