In planta screening of chili roots’ endophyte bacteria to control bacterial wilt disease

Ralstonia solanacearum is the causal agent of bacterial wilt disease. Here, we report that a large FAD-linked oxidase encoded by RSc0454 in GMI1000 is required for pathogenicity. The FAD-linked oxidase encoded by RSc0454 is composed of 1,345 amino acids, including DUF3683, lactate dehydrogenase (LDH), and succinate dehydrogenase (SDH) domains. The RSc0454 protein showed both LDH and SDH activities. To investigate its role in pathogenicity, a deletion mutant of the RSc0454 gene was constructed in GMI1000, which was impaired in its ability to cause bacterial wilt disease in tomato. A single DUF3683, LDH, or SDH domain was insufficient to restore bacterial pathogenicity. Mutagenesis of the RSc0454 gene did not affect growth rate but caused cell aggregation at the bottom of the liquid nutrient medium, which was reversed by exogenous applications of lactate, fumarate, pyruvate, and succinate. qRT-PCR and promoter LacZ fusion experiments demonstrated that RSc0454 gene transcription was induced by lactate and fumarate (both substrates of LDH). Compared with the downregulation of the succinate dehydrogenase gene sdhBADC and the lactate dehydrogenase gene ldh, RSc0454 gene transcription was enhanced in planta. This suggests that the oxidase encoded by RSc0454 was involved in a redox balance, which is in line with the different living conditions of R. solanacearum.

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PENGENDALIAN PENYAKIT LAYU BAKTERI NILAM MENGGUNAKAN Bacillus spp. DAN Pseudomonad fluoresen

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v15n3.2009.116-123 ◽

2020 ◽

Vol 15 (3) ◽

pp. 116

Author(s):

CHRISNAWATI CHRISNAWATI ◽

NASRUN NASRUN ◽

TRIWIDODO ARWIYANTO

Keyword(s):

Plant Growth ◽

Bacterial Wilt ◽

Block Design ◽

Wilt Disease ◽

Fluorescent Pseudomonad ◽

In Planta ◽

Bacterial Wilt Disease ◽

Pogostemon Cablin ◽

Bacillus Spp

ABSTRAKPenelitian pengendalian penyakit layu bakteri nilam (Ralstoniasolanacearum) menggunakan Bacillus spp. dan Pseudomonad fluoresen dikebun petani nilam di Nagari Kajai, Pasaman Barat, Sumatera Barat telahdilakukan pada bulan Mei sampai November 2006. Penelitian ini bertujuanuntuk mendapatkan Bacillus spp. dan Pseudomonad fluoresen yangberpotensi untuk mengendalikan penyakit layu bakteri, dan meningkatkanpertumbuhan dan produksi nilam. Isolat Bacillus spp. Bc 26; Bc 80 dan Bc81 dan Pseudomonad fluoresen Pf 101; Pf146 dan Pf 170 dalam bentukkombinasi sebagai perlakuan yang diisolasi dari rizosfer nilam sehat, dandiseleksi berdasarkan kemampuan antagonistik terhadap R. solanacearumsecara in vitro di laboratorium dan in planta di rumah kaca KP BalittroLaing Solok. Isolat Bacillus spp. dan Pseudomonad fluoresen tersebutdiintroduksikan ke nilam dan dibiarkan selama 1 minggu sebelum ditanam.Tanaman yang telah diperlakukan dengan isolat Bacillus spp. danPseudomonad fluoresen ditanam pada kebun nilam yang telah terinfeksioleh bakteri patogen pada bulan Mei 2006. Perlakuan yang diuji disusundalam rancangan acak kelompok (RAK) dengan 3 ulangan. Parameterpengamatan adalah perkembangan penyakit layu bakteri meliputi masainkubasi dan intensitas penyakit, pertumbuhan dan produksi tanaman.Hasil penelitian menunjukkan bahwa kombinasi isolat Bacillus spp. Bc26dan Pseudomonad fluoresen Pf101 dapat mengendalikan penyakit layubakteri nilam lebih baik dibandingkan dengan isolat Bacillus spp. Bc 26dan Pseudomonad fluoresen Pf 101 secara terpisah dan isolat Bacillus spp.dan Pseudomonad fluoresen lainnya secara kombinasi dan terpisah.Kombinasi isolat Bacillus spp. Bc 26 dan Pseudomonad fluoresen Pf 101dapat menunda masa inkubasi gejala penyakit layu bakteri dari 21 harisetelah tanam (HST) menjadi 63 HST dan menekan intensitas penyakitlayu bakteri dari 63,90% menjadi 14,67%. Di samping itu kombinasikedua isolat tersebut dapat meningkatkan pertumbuhan tanaman sepertitinggi tanaman dari 35,53 cm menjadi 52,77 cm, jumlah daun total dari32,00 daun/tanaman menjadi 104,67 daun/tanaman, jumlah tunas dari10,33 tunas/tanaman menjadi 25,33 tunas/tanaman, berat basah daun dari16,20 g/petak menjadi 81,73 g/petak dan berat kering daun dari 5,44 g/petak menjadi 27,15 g/petak. Hasil percobaan ini menunjukkan bahwakombinasi isolat Bacillus spp. Bc 26 dan Pseudomonad fluoresen Pf 101mempunyai kemampuan tertinggi dalam mengendalikan penyakit layubakteri dan meningkatkan pertumbuhan tanaman nilam di lapang.Kata kunci: Pogostemon cablin Benth, penyakit layu bakteri,pengendalian, Bacillus spp., Pseudomonad fluorescentABSTRACTUse of Bacillus sp. and Fluorecent Pseudomonad to Control Bacterial Wilt Disease on Patchouli PlantThe study of controlling bacterial wilt disease on patchouli plant(Ralstonia solacearum) with Bacillus spp. and Fluorescent pseudomonadwas carried out in farmer field in Kajai Village, West Pasaman, WestSumatra from May to November 2006. The aims of the study were to findout the effectiveness of Bacillus spp. and Fluorescent pseudomonad forcontrolling bacterial wilt disease, and increasing plant growth andproduction. Isolates of Bacillus spp. Bc 26, Bc 80, and Bc 81, andFluorescent pseudomonad Pf 101, Pf 146 and Pf 170 in combination orseperation as treatments were isolated from the rhizosphere of healthypatchouli plant, and selected based on antagonistic activity on R.solanacearum in vitro at the laboratory and in planta at green house of KP.Balittro Laing Solok. Isolates were inoculated on patchouli plant andremained for one week before planting. The plants, treated with Bacillusspp. and Fluorescent pseudomonad isolates, were planted in the fieldinfected with pathogen bacterial in May 2006. The treatment was arrangedin a randomized block design (RBD) with three replications. Theassessment parameters were incubation period, disease intensity, plantgrowth and production of patchouli plants. The results showed thatcombination of Bacillus spp. and Fluorescent pseudomonad could controlthe bacterial wilt disease better than Bacillus spp. Bc 26 and Fluorescentpseudomonad seperately, and the other Bacillus spp. and Fluorescentpseudomonad either in combination or separation. Combination ofBacillus spp. Bc26 and Fluorescent pseudomonad Pf 101 delayed theincubation period from 21 to 63 days and decreased the disease intensity ofbacterial wilt from 63.90 to 14.67%. In addition combination of bothisolates could affect the increase of plant growth, i.e plant height from35.53 to 52.77 cm, total numbers of leaves from 32.00 to 104 leaves/plant,budding numbers from 10.33 to 25.33 budding/plant, wet weight of leavesfrom 16.20 to 81.73 g/plot, and dry weight of leaves from 5.44 to 27.15g/plot. The results of the experiment showed that Bacillus spp. Bc 26 andFluorescent pseudomonad Pf 101 isolates have the highest activity oncontrolling the bacterial wilt disease and increase the growth of patchouliplant in the field.Key words: Patchouli, Pogostemon cablin Benth, bacterial wilt disease,biological control, Bacillus spp., Fluorescent pseudomonad

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Selection and Formulation of Endophytic Bacteria as Plant Resistance Elicitor against Wilt Disease of Tomato

Agrotechnology Research Journal ◽

10.20961/agrotechresj.v3i2.33866 ◽

2019 ◽

Vol 3 (2) ◽

pp. 103

Author(s):

Arika Purnawati ◽

Wiwik Harjani ◽

Herry Nirwanto

Keyword(s):

Plant Resistance ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Endophytic Bacteria ◽

Bacterial Isolate ◽

Disease Incidence ◽

Wilt Disease ◽

Seed Coating ◽

In Planta ◽

Bacterial Wilt Disease

Wilt disease of Solanaceae caused by Ralstonia solanacearum reduce the crop quality and negatively affect the crop product. The objective of this research was to discover of endophytic bacteria formulation that effectively decreases bacterial which cause wilt disease on Solanaceae. The research consisted of purification of Ralstonia solanacearum, endophytic bacteria were obtained from the sample and the screening of endophytic bacteria using this following assay: antagonist assay, seedling assay and in planta assay. The results showed that in antagonist assay, the bacterial isolate code PS1, PS2, and PS8 could inhibit growth of R. solanacearum. From the seedling assay, it obtained that all of the isolates increased of percentage of germination, seed coating and powder formulation can decrease disease incidence of bacterial wilt disease.

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1590 - Assembled rhizosphere bacteria by combined strategies of fumigation and organic amendment suppressed tomato bacterial wilt disease

10.26226/morressier.5b5199c3b1b87b000eceefca ◽

2018 ◽

Author(s):

Xuhui Deng ◽

Rong Li

Keyword(s):

Bacterial Wilt ◽

Organic Amendment ◽

Wilt Disease ◽

Rhizosphere Bacteria ◽

Bacterial Wilt Disease ◽

Tomato Bacterial Wilt

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Evaluation of seed associated endophytic bacteria from tolerant chilli cv. Firingi Jolokia for their biocontrol potential against bacterial wilt disease

Microbiological Research ◽

10.1016/j.micres.2021.126751 ◽

2021 ◽

pp. 126751

Author(s):

Bhaskar Dowarah ◽

Heena Agarwal ◽

Debasish B Krishnatreya ◽

Pankaj Losan Sharma ◽

Nilamjyoti Kalita ◽

...

Keyword(s):

Bacterial Wilt ◽

Endophytic Bacteria ◽

Wilt Disease ◽

Bacterial Wilt Disease ◽

Biocontrol Potential

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Ralstonia solanacearum Needs Motility for Invasive Virulence on Tomato

Journal of Bacteriology ◽

10.1128/jb.183.12.3597-3605.2001 ◽

2001 ◽

Vol 183 (12) ◽

pp. 3597-3605 ◽

Cited By ~ 201

Author(s):

Julie Tans-Kersten ◽

Huayu Huang ◽

Caitilyn Allen

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Soft Agar ◽

Cell Protein ◽

In Planta ◽

Tomato Plants ◽

Bacterial Wilt Disease ◽

Virulence Assay ◽

Flagellar Filament

ABSTRACT Ralstonia solanacearum, a widely distributed and economically important plant pathogen, invades the roots of diverse plant hosts from the soil and aggressively colonizes the xylem vessels, causing a lethal wilting known as bacterial wilt disease. By examining bacteria from the xylem vessels of infected plants, we found thatR. solanacearum is essentially nonmotile in planta, although it can be highly motile in culture. To determine the role of pathogen motility in this disease, we cloned, characterized, and mutated two genes in the R. solanacearum flagellar biosynthetic pathway. The genes for flagellin, the subunit of the flagellar filament (fliC), and for the flagellar motor switch protein (fliM) were isolated based on their resemblance to these proteins in other bacteria. As is typical for flagellins, the predicted FliC protein had well-conserved N- and C-terminal regions, separated by a divergent central domain. The predicted R. solanacearum FliM closely resembled motor switch proteins from other proteobacteria. Chromosomal mutants lackingfliC or fliM were created by replacing the genes with marked interrupted constructs. Since fliM is embedded in the fliLMNOPQR operon, the aphAcassette was used to make a nonpolar fliM mutation. Both mutants were completely nonmotile on soft agar plates, in minimal broth, and in tomato plants. The fliC mutant lacked flagella altogether; moreover, sheared-cell protein preparations from the fliC mutant lacked a 30-kDa band corresponding to flagellin. The fliM mutant was usually aflagellate, but about 10% of cells had abnormal truncated flagella. In a biologically representative soil-soak inoculation virulence assay, both nonmotile mutants were significantly reduced in the ability to cause disease on tomato plants. However, the fliC mutant had wild-type virulence when it was inoculated directly onto cut tomato petioles, an inoculation method that did not require bacteria to enter the intact host from the soil. These results suggest that swimming motility makes its most important contribution to bacterial wilt virulence in the early stages of host plant invasion and colonization.

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