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Infection cycle of tomato [Lycopersicon esculentum] yellow leaf curl virus (TYLCV) and preventing methods of TYLCV on nursery period
2009
Kato, S.(Aichi-ken. Agricultural Research Center, Nagakute (Japan)) | Torisawa, E. | Yoshida, K. | Saito, Y. | Suganuma, K. | Iida, F. | Fuji, S. | Fukuta, S. | Fukaya, M.
Tomato yellow leaf curl virus (TYLCV) has caused severe damage to tomato in Aichi prefecture. So we make cleared the infection cycle of TYLCV and developed the methods of TYLCV on nursery period. 1. Tomato is the most important host. 2. Transmission of TYLCV is caused by Bemisia tabaci B biotype and infection cycle is as indicated below. (1) summer-autumn: TYLCV moves from outdoor tomato to greenhouse tomato - (2) winter: TYLCV passes on greenhouse tomato - (3) spring: TYLCV moves from greenhouse tomato to outdoor tomato - repeat (1) to (3). 3. Insect nets with 0.4 mm mesh inhibited invasion of B. tabaci B biotype and as a result, infection of TYLCV was inhibited. 4. Granules applicated for B. tabaci B biotype prevented infection of TYLCV, but soluble powders, wettable powder and emulsifiable concentrate did not, in this study.
Afficher plus [+] Moins [-]The first occurrence of leaf mold of tomato caused by races 4.9 and 4.9.11 of Passalora fulva (syn. Fulvia fulva) in Japan Texte intégral
2009
Enya, Junichiro | Ikeda, Kentaro | Takeuchi, Taeko | Horikoshi, Norio | Higashi, Takahiko | Sakai, Takako | Iida, Yuichiro | Nishi, Kazufumi | Kubota, Masaharu
Tomato leaf mold caused by Passalora fulva was found on two tomato varieties carrying the Cf-9 gene in Japan, in 2007. The isolates obtained from Chiba and Fukushima were identified as race 4.9.11, and those from Gunma were races 4.9 or 4.9.11. This is the first report in Japan of tomato leaf mold caused by P. fulva strains that can overcome the Cf-9 gene.
Afficher plus [+] Moins [-]The first occurrence of leaf mold of tomato [Lycopersicon esculentum] caused by races 4.9 and 4.9.11 of Passalora fulva (syn. Fulvia fulva) in Japan
2009
Enya, J.(Mikado Kyowa Seed Co. Ltd., Chiba (Japan)) | Ikeda, K. | Takeuchi, T. | Horikoshi, N. | Higashi, T. | Sakai, T. | Iida, Y. | Nishi, K. | Kubota, M.
Tomato leaf mold caused by Passalora fulva was found on two tomato varieties carrying the Cf-9 gene in Japan, in 2007. The isolates obtained from Chiba and Fukushima were identified as race 4.9.1 1, and those from Gunma were races 4.9 or 4.9.11. This is the first report in Japan of tomato leaf mold caused by P. fulva strains that can overcome the Cf-9 gene.
Afficher plus [+] Moins [-]Blue mold of tomato caused by Penicillium oxalicum in Japan Texte intégral
2009
Umemoto, Seisaku | Odake, Youko | Takeuchi, Taeko | Yoshida, Shigenobu | Tsushima, Seiya | Koitabashi, Motoo
Blue mold of tomato caused by Penicillium oxalicum in Japan Texte intégral
2009
Umemoto, Seisaku | Odake, Youko | Takeuchi, Taeko | Yoshida, Shigenobu | Tsushima, Seiya | Koitabashi, Motoo
In 2006, stem rot and blue-green crusty lesions were found on the stems of tomato plants in Chiba Prefecture, Japan. Penicillium oxalicum was isolated repeatedly from the diseased plants. The causal fungus reproduced natural symptoms after artificial inoculation of tomato plants and was re-isolated from symptomatic plant tissue. P. oxalicum is a new pathogen that causes blue mold on tomato plants in Japan.
Afficher plus [+] Moins [-]Blue mold of tomato caused by Penicillium oxalicum in Japan
2009
Umemoto, S.(Chiba-ken. Agriculture and Forestry Research Center (Japan)) | Odake, Y. | Takeuchi, T. | Yoshida, S. | Tsushima, S. | Koitabashi, M.
In 2006, stem rot and blue-green crusty lesions were found on the stems of tomato plants in Chiba Prefecture, Japan. Penicillium oxalicum was isolated repeatedly from the diseased plants. The causal fungus reproduced natural symptoms after artificial inoculation of tomato plants and was re-isolated from symptomatic plant tissue. P. oxalicum is a new pathogen that causes blue mold on tomato plants in Japan.
Afficher plus [+] Moins [-]Virus-induced gene silencing reveals the involvement of ethylene-, salicylic acid- and mitogen-activated protein kinase-related defense pathways in the resistance of tomato to bacterial wilt Texte intégral
2009
Chen, Yong-Yi | Lin, Yu-Mei | Chao, To-Chun | Wang, Jaw-Fen | Liu, An-Chi | Ho, Fang-I. | Cheng, Chiu-Ping
Bacterial wilt (BW), caused by Ralstonia solanacearum, is a devastating vascular disease of tomato worldwide. However, information on tomato's defense mechanism against infection by this soil-borne bacterium is limited. In this study, virus-induced gene silencing (VIGS) was employed to decipher signaling pathways involved in the resistance of tomato to this pathogen. Defined sequence fragments derived from a group of genes known or predicted to be involved in ethylene (ET) and salicylic acid (SA) signaling transduction pathways and mitogen-activated protein kinase (MAPK) cascades were subjected to VIGS in 'Hawaii 7996', a tomato cultivar with stable resistance to BW, and their effect on resistance was determined. The results indicated that silencing of ACO1/3, EIN2, ERF3, NPR1, TGA2.2, TGA1a, MKK2, MPK1/2 and MPK3 caused significant increase in bacterial proliferation in stembases and/or mid-stems. Partial wilting symptoms appeared on plants in which TGA2.2, TGA2.1a, MKK2 and MPK1/2 were silenced. These results suggested that ET-, SA- and MAPK-related defense signaling pathways are involved in the resistance of tomato to BW. This is the first report elucidating the multiple layers of defense governing the resistance of tomato to BW. The results are discussed to enlighten an important and complex interaction between tomato and a soil-borne vascular pathogen.
Afficher plus [+] Moins [-]Complete sequences of tomato leaf curl Palampur virus isolates infecting cucurbits in Iran Texte intégral
2009
Heydarnejad, Jahangir | Mozaffari, Azadeh | Massumi, Hossain | Fazeli, Roya | Gray, Alistair J. A. | Meredith, Sandra | Lakay, Francisco | Shepherd, Dionne N. | Martin, Darren P. | Varsani, Arvind
Tomato leaf curl disease (TLCD) and and tomato yellow leaf curl (TYLCD) is caused by a number of begomovirus species that collectively threaten tomato production worldwide. We report here that an ongoing TLCD and TYLCD epidemic in Iran is caused by variants of tomato leaf curl Palampur virus (ToLCPMV), a newly proposed begomovirus species previously only detected in India. Besides infecting tomatoes, we identified ToLCPMV as the causal agent of a cucurbit disease that has devastated greenhouse cucumber and melon farms in Jiroft, southeastern Iran. We found no convincing evidence that the ToLCPMV DNA-B sequences have been derived through inter-species recombination, however, all of the currently sampled ToLCPMV DNA-A sequences are descendents of a sequence that probably arose through recombination between a ToLCNDV isolate and a currently unsampled geminivirus species that falls outside the ToLCNDV-ToLCPMV cluster. The increasing incidence of ToLCPMV in different cultivated species throughout Iran may signal the emergence of a serious new threat to agricultural production throughout the Middle East.
Afficher plus [+] Moins [-]First report of bacterial wilt of tomato (Solanum lycopersicum) caused by Ralstonia solanacearum in Benin Texte intégral
2009
Sikirou, R. | Beed, Fenton D. | Ezin, V. | Gbehounou, G. | Miller, S.A. | Wydra, K.
In June 2004, wilted tomatoes with no foliar yellowing were observed in Ouègbo, Atlantique District, Benin. The cut tomato stems released whitish bacterial ooze. Longitudinal sections of most stems showed brown vascular discoloration. Twenty symptomatic tomato plants were collected from 10 fields and exported to the Institute of Plant Disease and Plant Protection, Leibniz Universität Hannover, Germany. Bacteria were isolated on triphenyl tetrazolium chloride (TTC) medium (2) and three of the nine bacterial isolates that resembled Ralstonia solanacearum (colonies with red center and whitish periphery) and reference strain ToUdk (race 1 biovar 3; N. Thaveechai, Kasetsart University, Bangkok, Thailand) were used for pathogenicity tests. Five 4-week-old tomato plants cv. Tohounvi, grown in individual plastic pots (14 × 16 cm) containing sterilized field soil, were inoculated with each of the four isolates individually by soil drenching with 30 ml of the test cultures at 108 CFU/ml. Control plants were treated with 30 ml of sterile water. All plants were incubated in a glasshouse at 30°C. All plants inoculated with the isolates from Benin wilted 4 days after inoculation with symptoms similar to those observed in the field. Plants inoculated with the reference strain wilted 7 to 11 days after inoculation. Control plants treated with water remained healthy. R. solanacearum was recovered from the 20 symptomatic plants on TTC medium. The identity of the strains in comparison with the reference strain was confirmed by PCR with species-specific primers 759/760, which produced a single 281-bp fragment (3). Because similar symptoms were being increasingly reported by farmers across Benin and linked with reduced tomato yields, a disease survey was undertaken by IITA in 2006 and 2007. Wilted tomato plants were found across all agro-ecological zones of Benin (3 to 72% of plants per field). Isolates were recovered from the southeastern districts of Adja-Ouèrè, Sakété, Adjohoun, and Dangbo, the southwestern districts of Klouékanmè and Athiémé, the southern districts of Toffo and Bohicon, the central districts of Dassa and Savè, and the northern districts of Malanville and Karimama. Identification of R. solanacearum was confirmed following inoculation of tomato, production of characteristic wilting symptoms, recovery of the pathogen on TTC medium, and positive identification with ELISA kits (Pathoscreen Rs; Agdia Inc., Elkhart, IN). To our knowledge, this is the first report of R. solanacearum infecting tomato in Benin. Tomato is the most cultivated vegetable crop in Benin and important to the livelihood of many people in peri-urban and rural areas. Understanding that the cause of the observed crop losses is R. solanacearum may lead to implementation of management strategies such as deployment of disease-resistant cultivars or grafting tomatoes onto bacterial wilt-resistant rootstocks (1).References: (1) P. Aggarwal et al. Indian J. Agric. Sci. 78:379, 2008. (2) A. Kelman. Phytopathology 44:693, 1954. (3) N. Opina et al. Asian Pac. J. Mol. Biol. Biotechnol. 5:19, 1997.
Afficher plus [+] Moins [-]Evaluation of tomato crop by-products as feed for goats Texte intégral
2009
Ventura, M.R. | Pieltain, M.C. | Castanon, J.I.R.
The potential nutritive value of tomato by-products, both fruits and vegetative parts, was assessed by chemical analyses as well as by organic matter (OM) and crude protein (CP) in sacco degradability and in vitro organic matter digestibility. Tomato fruits contained 69g dry matter (DM) per kg fresh fruit and the average composition, per kg DM, was 923g OM, 28g ether extract (EE), 170g CP and 260g ash-free neutral detergent fibre (NDFom). Whole tomato plants contained 177g DM per kg fresh plant and their average composition, per kg DM, was 819g OM, 12g EE, 74g CP and 457g NDFom. Effective ruminal degradable and in vitro digestible OM content of tomato fruits were 534 and 583g/kg DM, respectively, and those of tomato plants were 274 and 474g/kg DM. Effective degradable CP content of tomato fruits and plants was, respectively, 33 and 20g/kg DM. Daily ingestion of fresh tomato fruits more than 1.5kg (about 100g DM) caused soft faeces in goats.
Afficher plus [+] Moins [-]Tomato yellow leaf curl disease and management in Northern Vietnam
2009
Ngo Bich Hao, Hanoi Agricultural Univ., Trau Qui Gia Lam, Hanoi (Vietnam) | Natsuaki, K., Tokyo Univ. of Agriculture Setagaya, Tokyo (Japan) | Nguyen Viet Hai, Post Entry Plant Quarantine, no. 1 Chem Tu Liem, Hanoi (Vietnam) | Ha Viet Cuong | Nguyen Ha Thi Quynh Trang | Vu Van Hai, Hanoi Agricultural Univ., Trau Qui Gia Lam, Hanoi (Vietnam)
Tomato yellow leaf curl disease (TYLCD) is the main limiting factor to production of tomato in North Vietnam. The causing agents of this disease as a complex of virus species that in nature are transmitted by the whitefly Bemissia tabaci. In the field, the disease is caused by at least two viruses of the genus Begamovirus (family Geminiviridae) with ss DNA, tomato leaf curl Vietnam virus (ToLCVVG, AF264063) and tomato yellow leaf curl Vietnam virus (TYLCVNV) and they are found in tomato leaf samples with yellow leaf curl symptom by PCR using specific primers for ToLCVV (ToLCVV-sp-F2 and ToLCVV-sp-R2) and TYLCVNV (TYLCVNV-sp-F2 and TYLCVNV-sp-R1). Management of the disease using tomato resistant varieties Magic and Savior and by vector control using yellow traps, a bio product 'Somec 2 SL', Bion and a pesticide Actara 25 WG, showed effective to decrease the population of the virus vector Bemissia tabaci and the occurrence of the disease in the fields.
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