Bakteri Ralstonia Solanacearum

Penyakit layu bakteri (PLB) yang disebabkan oleh Ralstonia solanacearum (RS)  merupakan salah satu penyakit utama tanaman kacang tanah yang tersebar luas di daerah tropis maupun subtropis. Bakteri RS memiliki kisaran inang yang luas dan menginfeksi lebih dari 33 famili termasuk tanaman budidaya dan tanaman inang lainnya seperti Croton hirtus, Crassocephalum crepidioides, Ocsimum basilicum, Sesbania rostrata, dan Crotalaria spp., selain itu juga RS dilaporkan dapat menginfeksi secara laten (latent of infection) dan dapat berkembang biak pada tanaman tanpa menimbulkan gejala layu.

Cabai merah (Capsicum annum L.) merupakan salah satu jenis tanaman sayuran yang memiliki nilai ekonomis tinggi dan banyak digemari oleh masyarakat. Pada umumnya masyarakat menggunakan cabai sebagai bahan masakan yang memberi rasa pedas pada masakan. Rasa pedas yang terdapat pada tanaman cabai dipengaruhi oleh kadar capsaicin pada tanaman cabai tersebut. Badan Pusat Statistik (2013) mencatat luas panen pada tahun 2010-2012 berturut-turut adalah 122.755 ha, 121.063 ha dan 120.275 ha, sedangkan produksinya mencapai 807.160 ton, 888.852 ton dan 954.363 ton. Dari data tersebut, produktivitas cabai berturut-turut 6,58 ton/ha, 7,34 ton/ha dan 7,93 ton/ha. Produktivitas tanaman cabai tergolong sangat rendah karena menurut (Agustin, Ilyas, Anas dan Suwarno, 2010) menyatakan bahwa potensi produktivitas tanaman cabai bisa mencapai 20-40 ton ha-1. Rendahnya produktivitas cabai antara lain disebabkan oleh serangan hama dan penyakit dan kurang tersedianya benih yang berkualitas. Salah satu penyakit yang menyerang tanaman cabai ialah penyakit layu bakteri. Penyakit ini cukup berbahaya karena pada tingkat serangan berat penyakit ini dapat menyebabkan kematian pada tanaman dan kegagalan panen sehingga menimbulkan kerugian atau penurunan hasil yang relatif besar (Semangun, 1994). Program pemuliaan tanaman ialah salah satu upaya untuk mendapatkan tanaman yang tahan terhadap serangan layu bakteri dan meningkatkan produktivitas tanaman cabai besar. Tujuan penelitian ini ialah untuk mengetahui ketahanan cabai merah (Capsicum annuum L.) terhadap serangan layu bakteri (Ralstonia solanacearum) dan kadar capsaicin yang terkandung dalam cabai merah (Capsicum annuum L.) pada 30 famili F5. Hipotesis yang diajukan dalam penelitian ini ialah terdapat beberapa cabai merah (Capsicum annuum L.) yang tahan terhadap serangan layu bakteri (Ralstonia solanacearum), produksi tinggi dan memiliki kadar capsaicin yang tinggi.
Penelitian ini dilaksanakan pada Januari hingga Juni 2015 di Desa Patok, Kecamatan Pujon, Kabupaten Malang dengan ketinggian tempat ±1100 m dpl dan suhu rata-rata 20o-27o C. Alat yang digunakan ialah rak tray, plastik semai, gembor, cangkul, meteran, alat pelubang mulsa, ajir bambu, tali rafia, timbangan analitik, papan penelitian, bambu, kamera dan alat tulis. Bahan yang digunakan ialah cocopeat, pupuk kompos, pupuk urea, pupuk SP-36, pupuk KCl dan 30 famili cabai merah generasi F5 hasil persilangan TW2 X PBC473 dan TW2 X Jatilaba. Metode penelitian menggunakaan metode single plot dengan menanam semua generasi F5 hasil seleksi cabai merah F4 tanpa ulangan. Variabel pengamatan yang diamati yaitu tinggi tanaman (cm), bobot per buah (g), diameter buah (cm), panjang buah (cm), jumlah buah per tanaman, intensitas serangan penyakit layu bakteri dan kadar capsaicin. Analisa data yang digunakan dalam penelitian ini berupa nilai koefisien keragaman genetik (KKG) dan koefisien keragaman fenotip (KKF).

Tomato (Lycopersicum esculentum) is an annual fruit plant that can be planted on high or low-land. Tomato has many beneficial vitamins and minerals to fulfill human body need for health. Tomato contains vitamins and minerals in amount of 30 calories, vitamin C 40 mg, vitamin A 1.500 SI, zinc, and calcium. Main cause of areal cultivation reduction are land degradation, erosions, and high intensity of bacterial wilt disease Ralstonia solanacearum that was the main consequences of perpetually tomato cultivation. Liquid fertilizer application gives some alternate way to control bacterial wilt disease Ralstonia solanacearum that also known as pathogen soil infection. Liquid fertilizer that used in this research is made from amino acid residual process. Purpose of this research is to observe the effect of liquid fertilizer giving that applied to the soil and leaves towards tomato plant growth. Result of this research shows that liquid root or foliar fertilizer application effects significantly on plant height and number of leaf parameters of all treatments and all observation time. ABSTRAK Tomat (Lycopersicum esculentum) ialah jenis sayuran buah semusim yang dapat ditanam di dataran rendah maupun tinggi. Tomat bermanfaat karena memiliki vitamin dan mineral yang diperlukan untuk pertumbuhan dan kesehatan. Tomat banyak mengandung vitamin dan mineral dengan jumlah kalori sebesar 30 kalori, vitamin C 40 mg, vitamin A 1.500 SI, zat besi, serta kalsium. Penyebab utama penurunan luas areal tomat ialah degradasi lahan, erosi, dan tingginya penyakit layu bakteri Ralstonia solanacearum yang diakibatkan dari penanaman tanaman tomat secara terus menerus tanpa adanya pergiliran tanaman. Penggunaan pupuk cair memberikan suatu alternatif untuk pengendalian penyakit layu bakteri Ralstonia solanacearum yang merupakan patogen tular tanah. Pupuk cair yang digunakan dalam penelitian ini berasal dari sisa proses asam amino atau salah satu jenis sipramin merupakan hasil dari industri.

Визначено стійкість сортів та гібридів картоплі шляхом штучного зараження в контрольованих умовах. Використана методика забезпечує достовірність і відтворюваність одержаних результатів та забезпечує чіткий контроль карантинного об’єкта в дослідженнях. Одержані таким способом дані можуть бути використані селекційними установами для створення сортів із підвищеною стійкістю проти збудника бурої бактеріальної гнилі. картопля, бура бактеріальна гниль, Ralstonia solanacearum, стійкість сортів і гібридів
Одним із важливих напрямів в галузі захисту рослин є вивчення стійкості сортів та гібридів сільськогосподарських культур проти патогенних мікроорганізмів. В останні роки, у зв’язку із глобальними змінами кліматичних умов, спостерігається збільшення ареалів розповсюдження збудників бактеріальних хвороб рослин. Одним з таких небезпечних патогенів є збудник бурої бактеріальної гнилі—бактерія

Background. Reliable genotyping that provides an accurate description of diversity in the context of pathogen emergence is required for the establishment of strategies to improve disease management. MultiLocus variable number tandem repeat analysis (MLVA) is a valuable genotyping method. It can be performed at small evolutionary scales where high discriminatory power is needed. Strains of the Ralstonia solanacearum species complex (RSSC) are highly genetically diverse. These destructive pathogens are the causative agent of bacterial wilt on an unusually broad range of host plants worldwide. In this study, we developed an MLVA scheme for genotyping the African RSSC phylotype III. Methods. We selected different publicly available tandem repeat (TR) loci and additional TR loci from the genome of strain CMR15 as markers. Based on these loci, a new phylotype III-MLVA scheme is presented. MLVA and multiLocus sequence typing (MLST) were compared at the global, regional, and local scales. Different populations of epidemiologically related and unrelated RSSC phylotype III strains were used. Results and Discussion. Sixteen polymorphic TR loci, which included seven mi-crosatellites and nine minisatellites, were selected. These TR loci were distributed throughout the genome (chromosome and megaplasmid) and located in both coding and intergenic regions. The newly developed RS3-MLVA16 scheme was more dis-criminative than MLST. RS3-MLVA16 showed good ability in differentiating strains at global, regional, and local scales, and it especially highlighted epidemiological links between closely related strains at the local scale. RS3-MLVA16 also underlines genetic variability within the same MLST-type and clonal complex, and gives a first overview of population structure. Overall, RS3-MLVA16 is a promising genotyping method for outbreak investigation at a fine scale, and it could be used for outbreak investigation as a first-line, low-cost assay for the routine screening of RSSC phylotype III.

Bacterial wilt caused by Ralstonia solanacearum is the world's most economically important destructive disease of crop plants. Fifty seven isolates of R. solanacearum causing wilt on different host plants were collected from different agro climatic zones of India of which 54 isolates were confirmed as race-1, biovar-3 and 3 isolates as race-1, biovar-3B based on morphological, physiological, biochemical and pathogenicity studies. All the isolates were authenticated as Ralstonia solanacearum by using two sets of primers (OLI1 & Y2 and Y1 & Y2). Serological identity of the isolates was done by using diagnostic kit obtained from International Potato Research Center, Lima, Peru and single chain variable fragment antibody specific to Ralstonia solanacearum. Fifty seven isolates of R. solanacearum were inoculated on tomato (Solanum Lycopersicum L) cv. Avinash-II under artificial conditions at bacterial concentration of 5x10 8 cfu/ml to test its aggressiveness; the results obtained are discussed in this paper.

Guidot, A., Elbaz, M., Carrère, S., Siri, M. I., Pianzzola, M. J., Prior, P., and Boucher, C. 2009. Specific genes from the potato brown rot strains of Ralstonia solanacearum and their potential use for strain detection. Phytopathology 99:1105-1112.

ABSTRACT Tomato (Lycopersicum esculentum) is an annual fruit plant that can be planted on high or low-land. Tomato has many beneficial vitamins and minerals to fulfill human body need for health. Tomato contains vitamins and minerals in amount of 30 calories, vitamin C 40 mg, vitamin A 1.500 SI, zinc, and calcium. Main cause of areal cultivation reduction are land degradation, erosions, and high intensity of bacterial wilt disease Ralstonia solanacearum that was the main consequences of perpetually tomato cultivation. Liquid fertilizer application gives some alternate way to control bacterial wilt disease Ralstonia solanacearum that also known as pathogen soil infection. Liquid fertilizer that used in this research is made from amino acid residual process. Purpose of this research is to observe the effect of liquid fertilizer giving that applied to the soil and leaves towards tomato plant growth. Result of this research shows that liquid root or foliar fertilizer application effects significantly on plant height and number of leaf parameters of all treatments and all observation time. Keywords: tomato, Ralstonia solanacearum, liquid fertilizer

Background: The Ralstonia solanacearum species complex includes thousands of strains pathogenic to an unusually wide range of plant species. These globally dispersed and heterogeneous strains cause bacterial wilt diseases, which have major socio-economic impacts. Pathogenicity is an ancestral trait in R. solanacearum and strains with high genetic variation can be subdivided into four phylotypes, correlating to isolates from Asia (phylotype I), the Americas (phylotype IIA and IIB), Africa (phylotype III) and Indonesia (phylotype IV). Comparison of genome sequences strains representative of this phylogenetic diversity can help determine which traits allow this bacterium to be such a pathogen of so many different plant species and how the bacteria survive in many different habitats.

Background.Reliable genotyping that provides an accurate description of diversity in the context of pathogen emergence is required for the establishment of strategies to improve disease management. MultiLocus variable number tandem repeat analysis (MLVA) is a valuable genotyping method. It can be performed at small evolutionary scales where high discriminatory power is needed. Strains of theRalstonia solanacearumspecies complex (RSSC) are highly genetically diverse. These destructive pathogens are the causative agent of bacterial wilt on an unusually broad range of host plants worldwide. In this study, we developed an MLVA scheme for genotyping the African RSSC phylotype III.Methods.We selected different publicly available tandem repeat (TR) loci and additional TR loci from the genome of strain CMR15 as markers. Based on these loci, a new phylotype III-MLVA scheme is presented. MLVA and multiLocus sequence typing (MLST) were compared at the global, regional, and local scales. Differ...

Background. Reliable genotyping that provides an accurate description of diversity in the context of pathogen emergence is required for the establishment of strategies to improve disease management. MultiLocus variable number tandem repeat analysis (MLVA) is a valuable genotyping method. It can be performed at small evolutionary scales where high discriminatory power is needed. Strains of the Ralstonia solanacearum species complex (RSSC) are highly genetically diverse. These destructive pathogens are the causative agent of bacterial wilt on an unusually broad range of host plants worldwide. In this study, we developed an MLVA scheme for genotyping the African RSSC phylotype III. Methods. We selected different publicly available tandem repeat (TR) loci and additional TR loci from the genome of strain CMR15 as markers. Based on these loci, a new phylotype III-MLVA scheme is presented. MLVA and multiLocus sequence typing (MLST) were compared at the global, regional, and local scales. D...

Survival of potato bacterial wilt disease was investigated in 107 infected potato samples under winter conditions in Sana’a,Yemen. Results obtained on the effect of over wintering low teperature on Ralstonia solanacearum showed that  the highest rate of the bacterium  population survival  was associated more with the monoculture of potato cv. Picasso  than other cultivars  with or without irrigation. The number  of colony forming  units (CFU) dropped rapidly to low levels at low temperature but not to undetectable levels, but with  temperature increase, recovery of colonies  occurred. Bacterial survival occurred on various crops or in the soil of unplanted pots, with or without irrigation. Wheat plants were the most effective in reducing bacterial population, as measured by the  CFU count. Such data support the assumption of using crop rotation  with wheat or  bean plants is more effective  in reducing the bacterial pathogen population as compared to no rotation or fallow soil. There was variability among the different bacterial isolates. Isolate 5 had the highest CFU, followed by that for isolates 6 and 4 with a mean of 37.61 x104, 34.17x104 and 33.00x104 (CFU), respectively. In five samples collected during winter, data showed that samples differed significantly in their associated bacterial populations, except for samples collected  on January 28,2010 and on March 18,2010.