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Suitable Integrated Approach for Management of Fusarium Wilt of Tomato caused by Fusarium oxysporum f. sp. lycopersici (Sacc.) Full text
2017
Kishan Lal | Pappu Singh | S. K. Biswas | Supriya Yadav | Virendra Kumar | Narender Kumar
Among the different integrated approaches for management of Fusarium wilt and their effect on growth and yield parameters of tomato revealed that soil application of FYM @ 100gm/pot + Neem cake @ 100gm/pot + seedling treatment with bio-formulation of Azotobater @ 5% + foliar spray of Carbendazim @ 0.1% was showing minimum disease incidence with 6.23, 10.11 and 15.03 per cent at 7, 14 and 21 days after inoculation, respectively. The observations on plant height of tomato was found in T3 treatment representing the value 17.00, 18.85, 20.66, 22.10, 24.10 and 27.30 cm at 5, 10, 15, 20, 25 and 30 days age of seedling, respectively against the minimum plant height i.e. 10.42, 10.92, 11.56, 11.76, and 12.55 in case of control (T10). The effect of integrated approach on branching of shoot in tomato was estimated at 85 days age of plant which revealed the maximum number of branch with 5.00 was found in case of soil application of FYM @ 100gm/pot + Neem cake@ 100gm/pot + seedling treatment with bio-formulation of Azotobater @ 5% + foliar spray of Carbendazim @ 0.1% whereas, in case of control it was only 2.33. The morphological character of roots was examined and recorded developed robust root system in T3 treatment while the less fibrous, weakly developed roots in control. The maximum yield was recorded per plant in T3 treatment (soil application of FYM @ 100gm/pot + Neem cake @ 100gm/pot + seedling treatment with bio-formulation of Azotobator @ 5% +foliar spray of Carbendazim @0.1%.) represented the value 490.30g per plant. Similarly, the maximum large size tuber with 4 in number was recorded in treatment T3 (soil application of FYM@ 100gm/pot+ Neem cake@ 100gm/pot + seedling treatment with bio-formulation of Azotobator@5% +foliar spray of Carbendazim @ 0.1%) followed by treatment T9 (Soil application of FYM @ 100 gm/pot + Neem cake @ 100 gm +seedling treatment with bio-formulation of T. viride + foliar spray Carbendazim @0.1%) as 03.
Show more [+] Less [-]Occurrence and identification of Stemphylium lycopersici causing Stemphylium leaf spot disease on tomato in Taiwan Full text
2017
Huang, Chien-Jui | Tsai, Wen-Shi
Tomato leaves showing severe leaf spot symptoms have been observed and sampled in the central west and southwest Taiwan during 2015 and 2016. The symptoms were similar to those of bacterial leaf spot/late blight diseases, but only Stemphylium-like fungi were consistently isolated from the diseased tomato. Upon spray inoculation of tomato, Stemphylium-like isolates caused leaf spot symptoms identical to those of naturally infected plants, and the pathogenic isolates were successfully re-isolated from inoculated leaves. The tomato-pathogenic isolates were identified as S. lycopersici based on morphological characterization and molecular identification. S. lycopersici has been previously reported to cause gray leaf spot of tomato in the temperate regions, but the majority of S. lycopersici-caused lesions were black/dark brown rather than gray in our surveillance. Accordingly, it is suggested that S. lycopersici-caused disease of tomato is named Stemphylium leaf spot of tomato more appropriately than tomato gray leaf spot. Moreover, S. lycopersici-caused leaf spot disease on tomato has been distributed in major tomato production regions in Taiwan. The information provided by our study will be important for future breeding of tomato cultivars, especially for tomato producers in Taiwan.
Show more [+] Less [-]Nailhead spot of tomato caused by Alternaria tomato (Cke.) N. Comb
1939
Weber, George F. (George Frederick)
Nailhead Spot of Tomato Caused by Alternaria tomato (Cke.) N. Comb
1939
Weber, George F. (George Frederick)
Association of tomato leaf curl Sudan virus with leaf curl disease of tomato in Jeddah, Saudi Arabia Full text
2016
Sohrab, Sayed Sartaj | Yāsir, Muḥammad | El-Kafrawy, Sherif Ali | Abbas, Ayman T. | Mousa, Magdi Ali Ahmed | Bakhashwain, Ahmed A.
Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed.
Show more [+] Less [-]Bacterial canker of tomato caused by corynebacterium michiganense
1969
Strider, David L.
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.
Show more [+] Less [-]Phytotoxicity of fumonisins and TA-toxin to corn and tomato
1994
Lamprecht, S.C. | Marasas, W.F.O. | Alberts, J.F. | Cawood, M.E. | Gelderblom, W.C.A. | Shephard, G.S. | Thiel, P.G. | Calitz, F.J.
The phytotoxic effects of five fumonisin mycotoxins produced by Fusarium moniliforme, i.e., fumonisin A1 (FA1), A2 (FA2), B1 (FB1), B2 (FB2), and B3 (FB3), together with the aminopolyol hydrolysis products of FB1 and FB2 (AP1 and AP2, respectively) and tricarballylic acid (TCA) were compared with the host-specific phytotoxin TA-toxin (TA) produced by Alternaria alternata f. sp. lycopersici. A leaf assay was performed on detached leaves of the tomato genotypes Asc/Asc (tolerant to TA) and asc/asc (sensitive to TA) at four concentrations (0.1, 1, 10, and 100 micromolar) of each toxin. Seedlings of corn cultivars A1849W and PNR 473 and the two tomato genotypes were also used to assay TA, FB1, FB2, and FB3. The fumonisins caused leaf necrosis identical to that caused by TA and FB1, FB2, FB3, and TA caused significantly (P = 0.01) more necrosis compared with the other metabolites tested. Sterile distilled water (control) and TCA caused no necrosis. Significantly (P = 0.01) more necrosis was observed on the asc/asc genotype compared with the Asc/Asc genotype. There was no significant (P > 0.05) difference between necrosis caused by autoclaved metabolites and that caused by nonautoclaved metabolites. The fumonisins caused dose-dependent reductions in shoot and root length and dry mass of corn and tomato seedlings identical to those caused by TA. The results indicated that TA and FB1 are more phytotoxic to seedlings than are FB2 and FB3. The effects of all four toxins were more pronounced on seedlings of the sensitive tomato genotype asc/asc than on the tolerant genotype Asc/Asc. No significant differences were recorded in the reaction of the two corn cultivars. The structural similarity of the fumonisin B mycotoxins and TA is therefore reflected by their phytotoxicity to detached tomato leaves as well as to corn and tomato seedlings.
Show more [+] Less [-]Effect of processing methods on the loss of lycopene content in tomato
2003
Praphan Pinsirodom(King Mongkut's Institute of Technology Ladkrabang, Bangkok (Thailand). Faculty of Agro-Industry)
Effect of processing methods (heat treatments, cold storages, and hot air drying) on the loss of lycopene content in tomato was studied. It was found that all the processing methods studied significantly caused the loss of lycopene content in tomato (p LT 0.05). The hot air drying of tomato resulted in the greatest loss of lycopene content (87.7 percent loss after drying at 65 deg C for 24 hr). Heat treatments of tomato pulp by pasteurizing at 72 deg C for 10 min showed 36.1 percent loss of lycopene content, while boiling of the pulp at 100 deg C for 1, 2 and 3 hr caused 63.9, 68.9 and 72.8 percent loss, respectively. In addition, heating of tomato pulp in an autoclave at 121 deg C and 15 psi for 15 min resulted in 49.3 percent loss of lycopene content. Cold and frozen storages of tomato pulp caused the lowest loss of lycopene content. About 20.1 percent and 31.1 percent loss were observed for tomato pulp stored at 5+-2 deg C for 15 days and at-10+-2 deg C for 4 weeks, respectively.
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