| dc.description.abstract | Cendawan Dark septate endophyte (DSE) dikenal sebagai kelompok cendawan endofit yang mampu melakukan kolonisasi pada akar tanaman inang tanpa menyebabkan munculnya gejala penyakit, serta dapat membentuk struktur melanisasi (hifa interseluler, hifa intraseluler dan mikrosklerotia) dalam akar tanaman, sehingga mampu berperan sebagai agen hayati, promotor pertumbuhan pada tanaman inang di bawah cekaman biotik dan abiotik. Selanjutnya kemampuan cendawan DSE untuk mendegradasi lignin dan selulosa belum banyak dipublikasikan terutama berkaitan dengan kemampuan menghasilkan enzim lignase yang berfungsi untuk mendegradasi lignin khususnya pada serasah P. merkusii. Penelitian ini dilakukan untuk mengevaluasi jenis-jenis DSE pada akar P. merkusii, mengevaluasi karakteristik pertumbuhan secara in vitro dan enzimatik isolat DSE, mengevaluasi kemampuan DSE dalam mendekomposisi serasah P. merkusii dan kemampuan antagonis DSE dari akar P. merkusii, mengevaluasi kemapuan DSE dalam meningkatkan pertumbuhan bibit P. merkusii dan mengevaluasi kemampuan DSE dalam menghambat penyakit lodoh yang diakibatkan oleh patogen Fusarium oxysporum pada bibit P. merkusii di rumah kaca.
Penelitian dilaksanakan di Laboratorium Biologi Balai Standarisasi Instrumen Pertanian, Jalan Tentara Pelajar No. 12, Kampus Penelitian Pertanian Cimanggu, Bogor, Jawa Barat dan Laboratorium Penyakit Hutan dan Rumah Kaca Departemen Silvikultur Fakultas Kehutanan dan Lingkungan IPB University, Bogor pada bulan September 2020 sampai September 2023. Penelitian dimulai dengan tahap pertama berupa isolasi dan karakteristik isolat DSE dari akar P. merkusii. Isolasi akar P. merkusii yang berasal dari 4 lokasi yaitu Dramaga Bogor, Hutan Pendidikan Gunung Walat Bogor, Taman Nasional Gunung Halimun Salak Bogor dan Kecamatan Dabun Gelang Kab. Gayo Lues, mengikuti metode Surono dan Narisawa (2017). Tahap kedua dilanjutkan uji pertumbuhan secara in vitro dan karakteristik enzimatik isolat DSE. Tahap ketiga melakukan uji kemampuan dekomposisi serasah P. merkusii dan antagonis isolat DSE. Tahap keempat mengevaluasi peran dan identifikasi isolat DSE sebagai pendukung pertumbuhan bibit P. merkusii di rumah kaca. Tahap kelima yaitu mengevaluasi peran isolat DSE terhadap penghambatan penyakit lodoh pada bibit P. merkusii di rumah kaca.
Data di analisis menggunakan program microsoft excel dan program SAS dan bila terdapat perbedaan antar perlakuan, dilakuan uji jarak berganda Duncan dengan taraf nyata q=0,05.
Hasil isolasi sebanyak 1.160 segmen akar P. merkusii, yang berasal dari 4 lokasi diperoleh sebanyak 25 isolat DSE. Isolasi akar P. merkusii dari kampus Dramaga IPB diperoleh sebanyak 16 isolat (5%), Kecamatan Dabun Gelang Kabupaten Gayo Lues diperoleh 2 isolat (0,79%), Hutan Pendidikan Gunung Walat diperoleh 2 isolat (2%) dan Taman Nasional Gunung Halimun Salak diperoleh 5 isolat (1,74%). Umunya warna hifa miselium isolat DSE yang diperoleh bagian atas berwana hitam dan rata-rata pertumbuhan isolat ≤ 2 mm per hari.
Pengujian pertumbuhan secara in vitro dengan menggunakan benih sawi.... | id |
| dc.description.abstract | Dark septate endophyte (DSE) fungi are known as a group of endophytic fungi
that are able to colonize the roots of host plants without causing disease symptoms, and
can form melanized structures (intercellular hyphae, intracellular hyphae and
microsclerotia) in plant roots, so that they are able to act as biological agents, growth
promoter in host plants under biotic and abiotic stresses. Furthermore, the ability of the
DSE fungus to degrade lignin and cellulose has not been widely published, especially
in relation to its ability to produce the enzyme lignase which functions to degrade lignin,
especially in P. merkusii litter. This research was conducted to evaluate the types of
DSE in P. merkusii roots, evaluate the in vitro and enzymatic growth characteristics of
DSE isolates, evaluate the ability of DSE to decompose P. merkusii litter and the
antagonistic ability of DSE from P. merkusii roots, evaluate the ability of DSE to
increase growth of P. merkusii seedlings and evaluating the ability of DSE to inhibit
lodoh disease caused by the pathogen Fusarium oxysporum on P. merkusii seedlings in
the greenhouse.
The research was carried out at the Biological Laboratory of the Agricultural
Instrument Standardization Center, Jalan Army Student No. 12, Cimanggu Agricultural
Research Campus, Bogor, West Java and Forest and Greenhouse Disease Laboratory,
Department of Silviculture, Faculty of Forestry and Environment, IPB University,
Bogor from September 2020 to September 2023. The research began with the first stage
in the form of isolation and characteristics of DSE isolates from P. merkusii roots.
Isolation of P. merkusii roots originating from 4 locations, namely Dramaga Bogor,
Gunung Walat Bogor University Forest, Gunung Halimun Salak Bogor National Park
and Dabun Gelang District, Kab. Gayo Lues, following the method of Surono and
Narisawa (2017). The second stage continued with in vitro growth tests and enzymatic
characteristics of DSE isolates. The third stage tested the decomposition ability of P.
merkusii litter and the DSE isolate antagonist. The fourth stage evaluated the role and
identification of DSE isolates as supporting the growth of P. merkusii seedlings in the
greenhouse. The fifth stage was evaluating the role of DSE isolates in inhibiting lodoh
disease on P. merkusii seedlings in the greenhouse.
Data were analyzed using the Microsoft Excel program and the SAS program
and if there were differences between treatments, Duncan's multiple range test was
carried out with a significance level of α=0.05.
The results of the isolation of 1,160 P. merkusii root segments, originating from
4 locations, resulted in 25 DSE isolates. Isolation of P. merkusii roots from the
Dramaga campus of IPB obtained 16 isolates (5%), Dabun Gelang District, Gayo Lues
Regency obtained 2 isolates (0.79%), Gunung Walat University Forest obtained 2
isolates (2%) and Gunung Halimun Salak National Park obtained 5 isolates (1.74%).
In general, the color of the mycelium hyphae of DSE isolates obtained at the top was
black and the average growth of the isolate was ≤ 2 mm per day.
In vitro growth testing using sweet caisim mustard seeds on 25 DSE isolates
showed that 12 isolates inhibited the growth of sweet caisim mustard seeds and 13
isolates did not show inhibition of the growth of sweet caisim mustard seeds.
Furthermore, 13 isolates that did not show inhibition of the growth of sweet caisim
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mustard seeds in vitro had their biomass measured. From these results, the control
treatment without administration of DSE isolates showed a significantly different
biomass, namely 0.0051 g when compared with isolates Hs 14.6c, Hs 14.6a, Pls 2.4,
Pls 12.5, Pls 32.1, Pls 17.4, Apls 1.5.3, Gw 1.5, Pls 18.1, Gw 37.6, Hs 14.6b, and Apg
23.5 and Apls 3.1.4 are 0.0043 g each, 0.0043 g, 0.0043 g, 0.0042g, 0.0039g, 0.0039g,
0.0038 g, 0.0038 g, 0.0037 g, 0.0035 g, 0.0034 g, 0.0034 g and 0.0034 g respectively.
Meanwhile, the treatment between isolates (inoculated with DSE) did not show any
significant differences. The results of enzymatic activity testing on 25 DSE isolates
using tannin acid and CMC media showed that 16 isolates had lignolytic enzyme
activity, 13 isolates had cellulolytic enzyme activity and 5 potential isolates were
obtained which were capable of producing lignocellulolytic enzyme activity, i.e,
isolates Apls 1.5.3, Pls 2.4, Pls 32.1, Hs 14.6a and Hs 14.6c. For the next research stage,
only 4 potential isolates were used except isolate Pls 2.4 because it experienced
contamination.
Decomposition testing on P. merkusii litter using DSE isolates Apls 1.5.3, Pls
32.1, Hs 14.6a and Hs 14.6c showed a positive effect on reducing the weight of fine
litter (40 mesh size) and the weight of coarse litter (2 cm size) when compared to the
control treatment. Next, antagonist testing was carried out for 4 DSE isolates, i.e, Apls
1.5.3, Pls 32.1, Hs 14.6a and Hs 14.6c, against 3 pathogenic isolates, namely Wlb, Wlc1
and Wlc2. The results of the DSE antagonist test for isolate Apls 1.5.3 which was given
an initial incubation period of 7 days and 14 days on PDA media using the double
culture method showed a significant inhibitory effect on the mycelium growth of
pathogenic isolates Wlb, Wlc1 and Wlc2.
Treatment of 4 DSE isolates, i.e, Apls 1.5.3, Pls 32.1, Hs 14.6a and Hs 14.6c on
P. merkusii seedlings for 14 weeks of incubation in the greenhouse, generally showed
a positive effect on the increase in height, stem diameter and root length when
compared. with control treatment (not inoculated with DSE). Overall, the biomass yield
of P. merkusii seedlings treated with DSE isolates was better than the control.
Colonization of the roots of P. merkusii seedlings showed that 4 DSE isolates i.e, Apls
1.5.3, Pls 32.1, Hs 14.6a and Hs 14.6c had a significant effect on the control treatment
(without DSE inoculation). DSE isolate Hs14.6c had a significant effect on the
absorption of nitrogen elements when compared to the control treatment (not inoculated
with DSE). The results of molecular identification and phylogenetic trees showed that
DSE isolate Apls 1.5.3 was similar to Cylindrocarpon sp, DSE isolates Hs14.6a and
Hs14.6c were similar to Cladophialophora sp and DSE isolate Pls 32.1 was similar to
Oncopodiella trigonella.
DSE testing of isolates Apls 1.5.3, Pls 32.1, Hs 14.6a and Hs 14.6c on the
inhibitory power of the Wlb pathogen on P. merkusii seedlings showed that the
application of DSE isolates Apls 1.5.3, Pls 32.1, Hs 14.6a and Hs 14.6c in general still
had a positive influence on the increase in height, stem diameter, root length and
biomass of P. merkusii seedlings compared to the control treatment. DSE treatment of
isolates Apls 1.5.3+ Wlb and Hs 14.6c + Wlb at month 7 still showed the highest
inhibition of 100% respectively when compared to the control. The results of molecular
analysis and phylogenetic trees of Wlb isolates are similar to Fusarium oxysporum and
are in the same branch as Fusarium oxysporum strain CP 23 with accession number
MH707084.1. | id |
