First Report of Bacterial Wilt Caused by Ralstonia solanacearum in Ghana, West Africa

Tomato and pepper plants exhibiting wilt symptoms were collected from fields in seven villages in Northern (Vea, Tono, Pwalugu), Ashanti (Agogo, Akumadan), and Brong Ahafo (Tanoso, Tuobodom) regions of western Ghana in November 2012. The plants were wilted without leaf yellowing or necrosis. Disease incidence was generally low, with less than 20% symptomatic plants observed. Most of the plants collected produced visible bacterial ooze in water in the field. Ooze was plated on 2,3,5-triphenyltetrazolium chloride-amended (TZC) medium. Isolated colonies were fluidal, irregularly round, white with pink centers, gram-negative, and oxidase positive. One strain from each of seven fields was selected for further study. All strains induced a hypersensitive reaction on tobacco. Randomly selected strains SM855-12 and SM857-12 tested positive in R. solanacearum ImmunoStrip assays (Agdia Inc., IN). An end-point PCR assay with primer set 759/760 (3) generated an R. solanacearum-specific 280-bp amplicon for all seven strains. Two of these strains were biovar I and the remaining five were biovar III based on utilization of cellobiose, lactose, maltose, dulcitol, mannitol, and sorbitol. A phylotype-specific multiplex PCR assay that recognizes four geographically linked monophyletic groups within R. solanacearum (1) indicated that one strain (SM855-12) was phylotype III (African origin), whereas the other six were phylotype I (Asian origin). All strains were subjected to repetitive sequence-based PCR (Rep-PCR) with BOXA1R and REP1R/REP2 primers (4). Strain SM855-12 was grouped with the phylotype III reference strain UW 368 and the remaining six strains were grouped with the phylotype I reference strain GMI 1000. A pathogenicity test was performed with bacterial wilt-susceptible tomato line OH7814. Inoculum was prepared from 48-h cultures of strains SM855-12, SM856-12, and SM858-12 grown on casamino acid peptone glucose (CPG) medium at 30°C. Roots of ten 4-week-old tomato plants per strain were drench-inoculated with 5 ml of a 108 CFU/ml bacterial suspension after wounding with a sterile scalpel. Non-inoculated control plants were drenched with 5 ml distilled water after root wounding. Plants were kept in a greenhouse at 25 to 30°C. By 12 days after inoculation, 80 to 100% of inoculated plants were wilted, whereas no symptoms appeared in non-inoculated plants. Bacteria re-isolated from wilted plants were confirmed to be R. solanacearum using techniques mentioned above. Although an association of bacterial wilt with tomato/pepper was mentioned previously (2), to our knowledge, this is the first documented report of bacterial wilt caused by R. solanacearum in Ghana. The presence of Asian strains (phylotype I) may be the result of one or more accidental introductions. Awareness of this disease in Ghana will lead to deployment of management strategies including use of resistant varieties and grafting desirable varieties onto disease-resistant rootstocks. References: (1) M. Fegan and P. Prior. Page 449 in Bacterial Wilt Disease and the Ralstonia solanacearum Species Complex. C. Allen et al., eds. American Phytopathological Society, St. Paul, MN, 2005. (2) K. A. Oduro. Plant Protection and Regulatory Services Directorate of MOFA, Accra, Ghana, 2000. (3) N. Opina et al. Asia Pac. J. Mol. Biol. Biotechnol. 5:19, 1977. (4) J. Versalovic et al. Methods Mol. Cell Biol. 5:25, 1994.

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First Report of Bacterial Wilt Caused by Ralstonia solanacearum on Plectranthus amboinicus in Martinique

Plant Disease ◽

10.1094/pdis-12-20-2622-pdn ◽

2021 ◽

Author(s):

Peninna Deberdt ◽

Gilles Cellier ◽

Régine Coranson-Beaudu ◽

Mathis Delmonteil--Girerd ◽

Joanye Canguio ◽

...

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Disease Incidence ◽

Bacterial Suspension ◽

Diagnostic Pcr ◽

Tomato Plants ◽

First Report ◽

Initial Symptoms ◽

Plectranthus Amboinicus ◽

Negative Controls

Plectranthus amboinicus, commonly known as Gwo ten in the French West Indies (Martinique), is a semi-succulent perennial plant of the Lamiaceae family. This aromatic plant wich is widespread naturally throughout the tropics is of economic importance because of the therapeutic and nutritional properties attributed to its natural phytochemical compounds wich are highly valued in the pharmaceutical industry. In March 2019, wilted P. amboinicus plants intercropped with tomato plants (cv. Heatmaster) in order to reduce the insect-pest damages on tomato, were observed in a field located at the CIRAD experimental station in Lamentin, Martinique (14.663194 N, -60.999167 W). Average disease incidence of 65.74% was recorded on P. amboinicus, in 3 plots with an area of 22.04 m2. The initial symptoms observed were irregular, black, necrotic lesions on leaves. After 10 days, plants wilted and black stripes were observed on stems. Within 4 weeks, more than 50% of plants were fully wilted. Longitudinal stem sections of the wilted plants showed brown vascular discoloration. The cut stems of the wilted plants released a whitish bacterial ooze in water. In all, 108 stem sections were collected, surface disinfected with 70% ethanol and each was crushed in 2 mL of Tris-buffer, then processed for bacterial isolation by plating on modified Semi-Selective Medium from South Africa SMSA (Engelbrecht 1994). Typical Ralstonia solanacearum colonies grew on SMSA medium for 100 of the 108 samples after incubation for 48h at 28°C and were identified as Ralstonia solanacearum using diagnostic PCR with 759/760 primers (Opina et al. 1997). A phylotype-specific multiplex PCR (Fegan and Prior 2005) classified all the strains in R. solanacearum Phylotype IIA. A subset of 11 strains was selected for sequevar identification. All the strains were identified as sequevar I-39 (100% nucleotide identity with strain ANT92 - Genbank accession EF371828), by partial egl sequencing (Fegan and Prior 2005) (GenBank Accession Nos. MT314067 to MT314077). This sequevar has been reported to be widespread in the Caribbean and tropical America on vegetable crops (particularly on tomato), but not on P. amboinicus (Deberdt et al. 2014; Ramsubhag et al. 2012; Wicker et al. 2007). To fulfil Koch’s postulates, a reference strain, isolated from diseased P. amboinicus (CFBP 8733, Phylotype IIA/sequevar 39), was inoculated on 30 healthy P. amboinicus plants. A common tomato cultivar grown in Martinique (cv. Heatmaster) was also inoculated on 30 plants with the same bacterial suspension. Three-weeks-old plants of both crops grown in sterilized field soil were inoculated by soil drenching with 20 ml of a calibrated suspension (108 CFU/mL). P. amboinicus and tomato plants drenched with sterile water served as a negative controls. Plants were grown in a fully controlled environment at day/night temperatures of 30–26°C ± 2°C under high relative humidity (80%). The P. amboinicus plants started wilting 9 days after inoculation, and within four weeks 60% of the P. amboinicus plants had wilted. The tomato plants started wilting 5 days after inoculation with 62% of wilted plants within four weeks. R. solanacearum was recovered from all symptomatic plants on modified SMSA medium. No symptoms were observed and no R. solanacearum strains were isolated from negative controls plants. To our knowledge, this is the first report of R. solanacearum causing bacterial wilt on Gwo ten (P. amboinicus) in Martinique. The importance of this discovery lies in the reporting of an additional host for R. solanacearum, which can be associated with other crops as tomato crop in order to reduce the abundance of insect-pests. Further studies need to be conducted to assess the precise distribution of bacterial wilt disease on P. amboinicus in Martinique and to develop a plan of action avoiding its association with R. solanacearum host crops as tomato for reducing epidemic risk.

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First report of Alternaria alternata causing leaf blight on little millet (Panicum sumatrense) in India.

Plant Disease ◽

10.1094/pdis-06-20-1373-pdn ◽

2020 ◽

Author(s):

Boda Praveen ◽

A. Nagaraja ◽

M. K. Prasanna Kumar ◽

Devanna Pramesh ◽

K. B. Palanna ◽

...

Keyword(s):

Crop Yields ◽

Disease Incidence ◽

Leaf Blight ◽

Post Inoculation ◽

Pathogenicity Test ◽

Conidial Suspension ◽

Pcr Assay ◽

Causal Organism ◽

First Report ◽

Little Millet

Little millet (LM) is a minor cereal crop grown in the Indian sub-continent. During October 2018, dark brown, circular to oval necrotic spots surrounded by concentric rings were observed on the upper leaf surface of the LM (cv. VS-13) grown in the fields of the University of Agricultural Sciences, Bengaluru, India (13.0784oN, 77.5793oE). As the disease progressed, infected leaves became blighted. Disease incidence up to 53% was recorded in 3 fields of 0.4-hectare area each. Thirty symptomatic leaves were collected to isolate the associated causal organism. The margins of diseased tissue were cut into 5 × 5-mm pieces, surface-sterilized in 75% ethanol for 45 seconds followed by 1% sodium hypochlorite for 1 min, finally rinsed in sterile distilled water five times and placed on PDA. After 7 days of incubation at 25°C, greyish fungal colonies appeared on PDA. Single-spore isolations were performed to obtain ten isolates. Pure cultures of the fungus initially produced light gray aerial mycelia that later turned to dark grey. All isolates formed obclavate to pyriform conidia measured 22.66-48.97μm long and 6.55-13.79µm wide with 1-3 longitudinal and 2-7 transverse septa with a short beak (2.55-13.26µm) (n=50). Based on the conidial morphology, the fungus was identified as Alternaria sp. Further, the taxonomic identity of all ten isolates was confirmed as A. alternata using species-specific primers (AAF2/AAR3, Konstantinova et al. 2002) in a PCR assay. Later, one of the isolate UASB1 was selected, and its internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (gapdh), major allergen Alt a 1 (Alt a 1), major endo-polygalacturonase (endoPG), OPA10-2, and KOG1058 genes were amplified in PCR (White et al. 1990; Berbee et al. 1999; Woudenberg et al. 2015), and the resultant products were sequenced and deposited in the NCBI GenBank (ITS, MN919390; gapdh, MT637185; Alt a 1, MT882339; endoPG, MT882340; OPA10-2, MT882341; KOG1058, MT882342). Blastn analysis of ITS, gapdh, Alt a 1, endoPG, OPA10-2, KOG1058 gene sequences showed 99.62% (with AF347031), 97.36% (with AY278808), 99.58% (with AY563301), 99.10% (with JQ811978), 99.05% (with KP124632) and 99.23% (with KP125233) respectively, identity with reference strain CBS916.96 of A. alternata, confirming UASB1 isolate to be A. alternata. For pathogenicity assay, conidial suspension of UASB1 isolate was spray inoculated to ten healthy LM (cv. VS-13) plants (45 days old) maintained under protected conditions. The spore suspension was sprayed until runoff on healthy leaves, and ten healthy plants sprayed with sterile water served as controls. Later, all inoculated and control plants were covered with transparent polyethylene bags and were maintained in a greenhouse at 28±2 ◦C and 90% RH. The pathogenicity test was repeated three times. After 8 days post-inoculation, inoculated plants showed leaf blight symptoms as observed in the field, whereas no disease symptoms were observed on non-inoculated plants. Re-isolations were performed from inoculated plants, and the re-isolated pathogen was confirmed as A. alternata based on morphological and PCR assay (Konstantinova et al. 2002). No pathogens were isolated from control plants. There is an increasing acreage of LM crop in India, and this first report indicates the need for further studies on leaf blight management and the disease impacts on crop yields.

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First Report of Ralstonia solanacearum Phylotype I Causing Bacterial Wilt on Rosa spp. in Korea

Plant Disease ◽

10.1094/pdis-09-18-1604-pdn ◽

2019 ◽

Vol 103 (6) ◽

pp. 1407

Author(s):

Y. S. Kim ◽

S. R. Lim ◽

J.-W. Kim ◽

H.-J. Lee ◽

D. H. Park

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

First Report ◽

Phylotype I

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First Report of Bacterial Wilt of Tomato Caused by Ralstonia pseudosolanacearum (Ralstonia solanacearum phylotype I) in Cambodia

Plant Disease ◽

10.1094/pdis-09-19-1823-pdn ◽

2020 ◽

Vol 104 (3) ◽

pp. 969-969

Author(s):

T. L. Klass ◽

M. M. Hayes ◽

K. H. Seng ◽

C. An ◽

F. Rotondo ◽

...

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

First Report ◽

Ralstonia Pseudosolanacearum ◽

Phylotype I

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Screening Cultivated Eggplant and Wild Relatives for Resistance to Bacterial Wilt (Ralstonia solanacearum)

Agriculture ◽

10.3390/agriculture9070157 ◽

2019 ◽

Vol 9 (7) ◽

pp. 157 ◽

Cited By ~ 3

Author(s):

Namisy ◽

Chen ◽

Prohens ◽

Metwally ◽

Elmahrouk ◽

...

Keyword(s):

High Temperatures ◽

Resistance Genes ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Solanum Melongena ◽

Wild Relatives ◽

Sources Of Resistance ◽

Race 1 ◽

Moderately Resistant ◽

Phylotype I

Bacterial wilt, caused by Ralstonia solanacearum, is highly diverse and the identification of new sources of resistance for the incorporation of multiple and complementary resistance genes in the same cultivar is the best strategy for durable and stable resistance. The objective of this study was to screen seven accessions of cultivated eggplant (Solanum melongena L.) and 40 accessions from 12 wild relatives for resistance to two virulent R. solanacearum strains (Pss97 and Pss2016; phylotype I, race 1, biovar 3). The resistant or moderately resistant accessions were further evaluated with Pss97 in a second trial under high temperatures (and also with Pss2016 for S. anguivi accession VI050346). The resistant control EG203 was resistant to Pss97, but only moderately resistant to Pss2016. One accession of S. sisymbriifolium (SIS1) and two accessions of S. torvum (TOR2 and TOR3) were resistant or moderately resistant to Pss97 in both trials. Solanum anguivi VI050346, S. incanum accession MM577, and S. sisymbriifolium (SIS1 and SIS2) were resistant to Pss2016 in the first trial. However, S. anguivi VI050346 was susceptible in the second trial. These results are important for breeding resistant rootstocks and cultivars that can be used to manage this endemic disease.

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Molecular Epidemiology of Ralstonia solanacearum Species Complex Strains Causing Bacterial Wilt of Potato in Uganda

Phytopathology ◽

10.1094/phyto-12-18-0476-r ◽

2019 ◽

Vol 109 (11) ◽

pp. 1922-1931 ◽

Cited By ~ 6

Author(s):

Abdulwahab Abdurahman ◽

Monica L. Parker ◽

Jan Kreuze ◽

John G. Elphinstone ◽

Paul C. Struik ◽

...

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Species Complex ◽

Nationwide Survey ◽

Potato Production ◽

Repeat Sequence ◽

Latently Infected ◽

Pure Cultures ◽

Diversity Studies ◽

Phylotype I

Bacterial wilt (BW) caused by the Ralstonia solanacearum species complex (RSSC) is a serious threat to potato production in Uganda. However, little is known about the extent of the disease and the type of the pathogen strains involved. A nationwide survey was conducted to study BW prevalence and incidence in potato, and potato tuber and stem samples of potential alternative hosts were collected for pathogen isolation. DNA was extracted from pure cultures for genetic diversity studies. The pathogen was phylotyped by multiplex PCR; then, a subset of isolates was typed at sequevar level. Isolates of the same sequevar were then haplotyped using multilocus tandem repeat sequence typing (TRST) schemes. BW prevalence and incidence in potato farms were 81.4 and 1.7%, respectively. Three RSSC phylotypes were identified, with the majority of the strains belonging to Phylotype II (80%) followed by Phylotype I (18.5%) and III (1.5%). Phylotype I strains belonged to Sequevar 31, and Phylotype II strains belonged to Sequevar 1. Potato-associated Phylotype II Sequevar 1 strains were more diverse (27 TRST haplotypes) than nonpotato Phylotype I (5 TRST haplotypes). Mapping of TRST haplotypes revealed that three TRST haplotypes of Phylotype II Sequevar 1 strains play an important epidemiological role in BW of potato in Uganda being disseminated via latently infected seed. [Formula: see text] Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

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Reaction of Capsicum peppers commercialized in the Federal District to bacterial wilt

Horticultura Brasileira ◽

10.1590/s0102-053620180204 ◽

2018 ◽

Vol 36 (2) ◽

pp. 173-177 ◽

Cited By ~ 3

Author(s):

Maurício Rossato ◽

Thais R. Santiago ◽

Carlos Alberto Lopes

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Bacterial Pathogens ◽

Federal District ◽

Capsicum Frutescens ◽

Capsicum Baccatum ◽

Main Species ◽

Race 1 ◽

Resistant Group ◽

Phylotype I

ABSTRACT In Brazil, the bacterial pathogens Ralstonia solanacearum and R. pseudosolanacearum cause substantial losses by inducing bacterial wilt on several solanaceous crops; R. pseudosolanacearum is the main species associated with peppers (Capsicum sp.). To verify the bacterial wilt reaction on Capsicum peppers commercialized in the Federal District (DF), fruits of several genotypes within this genus were collected from six different fairs distributed in the satellite cities of Gama, Sobradinho and Guará. Seedlings with four true leaves derived from seeds extracted from such fruits were root inoculated with 108 CFU/mL with a representative isolate of R. pseudosolanacearum (race 1, biovar 3, phylotype I, sequevar 18). The evaluated species were: Capsicum frutescens (‘pimenta-malagueta’), Capsicum baccatum var. pendulum (‘pimenta-dedo-de-moça’) and C. chinense (‘pimenta-de-bode’ red and yellow, ‘pimenta-cumarí-do-Pará’, ‘pimenta-biquinho’, ‘pimenta-habanero’ and ‘pimenta-de-cheiro’). Not all species were found in all six fairs. The reaction to bacterial wilt was variable and species-dependent. From 26 evaluated genotypes, none presented an immune-like response, 10 were considered resistant and 16 susceptible based on wilt incidence (Scott-Knott, 5%). Four Capsicum baccatum accesses were positioned in the resistant group, whereas 14 out of 18 of C. chinense were susceptible. Capsicum frutescens showed variable reactions. These results contribute to indicate cultivation of specific groups of pepper according to the presence of the pathogen in the soil.

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Characteristics of Ralstonia solanacearum Strains of Potato Wilt Disease from Nepal and Thailand

Nepal Agriculture Research Journal ◽

10.3126/narj.v4i0.4868 ◽

1970 ◽

pp. 42-47 ◽

Cited By ~ 1

Author(s):

Shambhu P Dhital ◽

Nanda Thaveechai ◽

Sundar K Shrestha

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Hypersensitive Reaction ◽

Wilt Disease ◽

Pathogenicity Test ◽

Serological Tests ◽

Bacterial Wilt Disease ◽

Research Journal ◽

Limited Host Range ◽

Potato Wilt

Characterization of strains of Ralstonia solanacearum, the causal agent of potato bacterial wilt disease from Nepal and Thailand was performed based on pathogenicity, biochemical/physiological and serological tests. Fifteen R. solanacearum strains isolated from wilt infected potato plants and tubers grown in Nepal were characterized as race 3, biovar II based on the pathogenicity on different host plants, hypersensitive reaction on tobacco leaf and utilization of some sugars. Results of pathogenicity test show that all strains from Nepal had limited host range. Degree of virulence of all strains varied from high to medium in potato and tomato and medium to low in eggplant. They did not cause wilting in tobacco, pepper and peanut plants. Six strains from Thailand were characterized as biovar II and III. Additionally, comparisons on the physiological, biological and serological characters of seven strains from Nepal and six from Thailand revealed similar characters. Race 3 and biovar II of the pathogen was widely spread over potato growing areas of mid and high hills of Nepal. Both biovars II and III were prevalent in the potato growing areas of Thailand but biovar III was the most dominating one.Key words: Bacterial wilt; Potato; Pseudomonas solanacearum; Ralstonia solanacearumDOI: http://dx.doi.org/10.3126/narj.v4i0.4868Nepal Agriculture Research Journal Vol. 4&5, 2001/2002Page: 42-47Uploaded date: 9 June, 2011

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POTENTIAL OF MEDICINAL PLANT EXTRACTS IN INDUCING PLANT RESISTANCE ON GINGER AGAINST BACTERIAL WILT DISEASE

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v20n4.2014.187-194 ◽

2020 ◽

Vol 20 (4) ◽

pp. 187

Author(s):

SRI YUNI HARTATI ◽

SUPRIADI SUPRIADI ◽

SRI RAHAYUNINGSIH

Keyword(s):

Salicylic Acid ◽

Medicinal Plant ◽

Plant Extracts ◽

Plant Resistance ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Disease Incidence ◽

Wilt Disease ◽

Bacterial Wilt Disease ◽

Medicinal Plant Extracts

ABSTRACT Bacterial wilt caused by Ralstonia solanacearum is one of the most destructive diseases on ginger. The aim of this study was to evaluate the potential use of five different medicinal plants extracts (Acalypha indica, Andrographis paniculata, Centella asiatica, Curcuma xanthorrhiza, and Spinosa oleracea) as sources of plant resistance inducer compounds (elicitor) against bacterial wilt disease on ginger. Salicylic acid was used as a standard synthetical compound, as well as, water as a control treatment. The study was conducted at the Indonesian Spice and Medicinal Crops Research Institute, Bogor in 2010-2011. Research was conducted in Completely Randomized Design that consisted of 7 treatments, 3 replicates, and 10 plants/ replicate. Ginger seeds were planted in a mixture of soil and manure in polybags. One-month old ginger plants were sprayed or drenched with each of the medicinal plant extract before and after R. solanacearum inoculation. This experiment indicated that the medicinal plant extracts tested were effective in reducing wilt disease incidence on ginger. Their effectiveness varied depended on the plant species and the application method used. Among those five medicinal plant extracts tested, A. indica, A. paniculata, and C. xanthorrhiza were the most stable and effective. Their effectiveness were comparable with the standard compound of salicylic acid. This finding indicated that A. indica, A. paniculata, and C. xanthorrhiza were potentially used as sources of botanical elicitor compounds. The use of those medicinal plant extracts as sources of botanical elicitor, hopefully could increase ginger resistance and rhizome production, as well as reduce the use of synthetic pesticides. Keywords: Medicinal plant extracts, elicitor compounds, induced resistance, ginger, wilt disease ABSTRAK Layu bakteri yang disebabkan oleh Ralstonia solanacearum merupakan salah satu penyakit yang merusak tanaman jahe. Penelitian ini bertujuan untuk mengevaluasi potensi lima jenis ekstrak tanaman obat (akar kucing, sambiloto, pegagan, temulawak, dan bayam duri) sebagai sumber senyawa penginduksi ketahanan (elisitor) tanaman jahe terhadap penyakit layu. Pada penelitian ini digunakan asam salisilat sebagai senyawa sintetik standard dan air sebagai perlakuan kontrol. Penelitian dilaksanakan di Balai Penelitian Tanaman Rempah dan Obat, Bogor pada tahun 2010-2011. Percobaan dilaksanakan dengan menggunakan rancangan acak lengkap yang terdiri atas 7 perlakuan, 3 ulangan, dan 10 tanaman/ ulangan. Rimpang jahe ditanam pada media campuran tanah dan pupuk kandang di dalam polibeg. Jahe umur satu bulan disemprot atau disiram dengan ekstrak tanaman obat sebelum dan setelah diinokulasi R. solanacearum. Hasil penelitian mengindikasikan bahwa ekstrak tanaman obat yang diuji efektif dapat mengurangi kejadian penyakit layu pada tanaman jahe. Efektivitas dari tanaman tersebut bervariasi tergantung dari spesies tanaman dan cara aplikasinya. Diantara kelima tanaman obat yang diuji, akar kucing, sambiloto, dan temulawak paling stabil dan efektif dalam mengurangi terjadinya penyakit layu. Efektivitas dari ketiga tanaman obat tersebut sama dengan senyawa asam salisilat. Hasil penelitian menunjukkan bahwa akar kucing, sambiloto, dan temulawak berpotensi untuk digunakan sebagai sumber senyawa elisitor botanis. Penggunaan ekstrak tanaman obat sebagai sumber elisitor botanis diharapkan dapat meningkatkan ketahanan tanaman dan produksi jahe serta mengurangi penggunaan pestisida sintetik. Kata kunci: Ekstrak tanaman, senyawa elisitor, induksi ketahanan, jahe, penyakit layu.

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