Damping-off disease commonly occurs in nursery plant under field conditions. Incidence of the disease was highest at village Darya Khan Nahiyoun (65.0%) followed by Khatian Station (60.0%) and Rahooki (55.0%). The lowest was recorded at Khesano Mori (35.0%). Damping-off fungi viz., Rhizoctonia solani, Fusarium oxysporum f.sp. lycopersici, Macrophomina phaseolina, Alternaria solani and Verticillium albo-atrum were isolated rotted rot pieces of tomato seedlings. Rhizoctonia solani was isolated with highest frequency (60.0%). Pathogenicity test of Rhizoctonia solani gave the positive results. The maximum numbers of infected plants were obtained after 30 days of sowing from both the treatments, infested seed and soil. The disease incidence was highest in infested seed (65.625%). Four seed dressing fungicides Topsin-M, Benlate, Copper Oxychloride and Derosal were used as seed treatment and soil drench against the fungus, Rhizoctonia solani. Topsin- M significantly increased the seed germination (7 and 15 days of sowing), plant growth and number of healthy plants both seed treatment and soil drench followed by Benlate as compared to copper oxychloride, Derosal and Untreated seeds and soil. Fungicides applied as soil was found as the best method than the fungicides used as seed treatment. The maximum disease was recorded in tomato plants collected from village Darya Khan Nahiyoun (65.00%) followed by Khatian Station (60.00%) Rhizoctonia solani (Kuhn) was insolated as most predominant fungus with highest frequency (60.00%) followed by Fusarium oxysporum f.sp. lycopersici. Rhizoctonia solani was found as more pathogenic on seeds artificially inoculated with the fungus than the soil infested with the fresh culture of the fungus. The maximum disease incidence was recorded from infested seed (65.62%) Topsin-M was found as the best fungicide increasing seed germination, number of plants and plant growth when used as seed treat m ent as well as soil drench.

A doença causada pelo complexo de vírus do tomato yellow leaf curl (TYLC) é muito séria em tomateiro, principalmente na América Central e Europa, e é causada por um complexo de begomovírus monopartidos. A doença torna-se predominante, mesmo em áreas com a presença de outros begomovírus. No Brasil, os problemas advindos da infecção por begomovírus uram entre os principais fatores de perdas e oneração de custos. A introdução do complexo TYLC representa uma grande ameaça para os produtores. Este estudo visou a realização de testes de detecção baseados em reação de polimerase em cadeia (PCR) e hibridização específicos em amostras suspeitas coletadas no estado de São Paulo. Um total de 46 amostras com sintomas lembrando aqueles causados pelo complexo TYLC foram coletados no município de Campinas. Todas as amostras foram negativas para detecção de Tomato yellow leaf curl virus e Tomato yellow leaf curl Sardinia virus, as duas espécies mais importantes do completo TYLC. Este resultado sugeriu que as duas espécies de vírus ainda não foram introduzidas no Brasil ou que ainda não apresentam uma larga distribuição. | The disease caused by the virus complex of tomato yellow leaf curl (TYLC) is extremely severe in tomato plants, notably in Central America and Europe, and is caused by a complex of begomovirus species. The disease becomes predominant even in areas with the presence of other begomoviruses. In Brazil. the problems arisen from begomovirus infection are one of the major factors for damages and increasing the costs. The introduction of the TYLC complex implies in a great threat for growers. This study aimed to carry out detection tests based on PCR (polymerase chain reaction) and specific hybridization on suspected samples collected in the São Paulo State, Brazil. A total of 46 samples with symptoms resembling those caused by the TYLC complex were collected in Campinas county. All samples were negative for the detection of Tomato yellow leaf curl virus and Tomato yellow leaf curl Sardinia virus, the two most important virus from the TYLC complex. This result suggested that the two species have not yet been introduced in Brazil or that they are not widespread.

Epidemics of spotted wilt caused by Tomato spotted wilt virus (TSWV) vectored by Frankliniella occidentalis and possibly other thrips species occur regularly in tomato in the southeastern United States. Field experiments were conducted to determine the effects of UV-reflective mulch, acibenzolar-S-methyl (plant activator), and insecticides on progress of tomato spotted wilt incidence and population dynamics of flower thrips (including F. occidentalis, F. tritici, and F. bispinosa). Whole plots of tomatoes grown on UV-reflective and black polyethylene mulch were divided into subplots of acibenzolar-S-methyl and no acibenzolar-S-methyl, and sub-subplots of insecticide and no insecticide for thrips control. The UV-reflective mulch was more effective than black polyethylene mulch each year in reducing colonization of thrips in May and the consequent primary infections of tomato spotted wilt. Application of acibenzolar-S-methyl further reduced tomato spotted wilt incidence in 2000 and 2002, when disease pressure was great. Reproduction of thrips on tomato was poor in these experiments, but their control in the insecticide-treated sub-subplots prevented secondary spread in both years. The combination of UV-reflective mulch, acibenzolar-S-methyl, and insecticides was very effective in reducing tomato spotted wilt incidence in tomato.

The seasonings used were salt, soy sauce, sake, vinegar, sugar, curry powder, and tomato paste. They were added in the amount of 1.5,10.35, 5, 5, 3,1, 15 (g/100g of rice), respectively, or with twice as much. The rice cooked with seasonings was prepared with 1.5 (w/w) ratio of water to rice. Rheological properties of cooking water with vinegar, curry powder and tomato paste were larger in viscosity and yield value than those without seasonings, those might cause the stickiness of cooked rice. The addition of all seasonings caused the rise of gelatinization temperature and increase in gelatinization energy. Those were remarkably in salt, soy sauce and tomato paste. After 24 hours of standing at 5 deg C, the degree of gelatinization of the rice cooked with soy sauce, sugar, curry powder, and tomato paste were significantly lower than those without seasonings. Preliminary degassing of tomato paste before adding to the cooking water was effective for the improvement of the physicochemical properties of cooked rice.

The aim of this study was to investigate the effect of different types of tomato processing on contents of lycopene, beta-carotene, and alpha-tocopherol. Samples of tomato sauce, tomato soup, baked tomato slices, and tomato juice were taken at different times of heating, respectively, after each step of production. HPLC was used to analyze contents of carotenoids and vitamin E. Due to the loss of water during thermal processing, contents of lycopene, beta-carotene, and alpha-tocopherol on a wet weight basis increased. On a dry weight basis, contents of lycopene increased or decreased depending on the origin of the tomatoes used, whereas the beta-carotene contents decreased or were quite stable. In contrast to lycopene, beta-carotene isomerized due to thermal processing. The alpha-tocopherol contents significantly rose during short-term heating. The increase was not caused by release of alpha-tocopherol from the seeds containing predominantly gamma-tocopherol and accounting for 2% of total alpha-tocopherol content only.

International audience | Tomato pith necrosis (TPN) is caused mainly by soil-borne Pseudomonas spp., formerly known as Pseudomonas corrugata. Considerable phenotypic diversity and evidence of genomic variability were the basis of the characterization of two species within this group: P. corrugata and P. mediterranea sp. nov. Both have been isolated in several countries, including Portugal. There is no report on the relative aggressiveness of these two TPN-causing Pseudomonas species under commercial-like greenhouse conditions. In this study, the severity and progress of pith necrosis caused by P. corrugata and P. mediterranea were compared under spring/summer greenhouse conditions in northern Portugal. In addition, a precise assessment of the yield of tomatoes (number, size and weight of fruits) was carried out to determine the relationship among bacterial species, disease severity and yield loss. Tomato plants were stem-injected with either strain A344 of P. corrugata or strain A54 of P. mediterranea, 45 and 60 days after transplantation in the greenhouse. TPN symptoms were recorded throughout the growing period. Yield of tomato fruits was assessed weekly during the last seven weeks. Both strains showed a similar level of aggressiveness and caused the same type of symptoms. Both strains were responsible for significant yield reductions, however, no correlation (Pmore than or equal to 0.05) was found between pith lesion length and fruit loss

The fruit borer Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is a serious pest of several crops in India. Among these, tomato, cotton, pigeon pea, and chickpea consistently suffer extensive damage by the insect in different parts of the country. The pesticides no longer control the insect. Among the alternative tactics for its control, transgenic plants expressing toxic proteins of Bacillus thuringiensis offer a sustainable and effective method to prevent the crop losses because of H. armigera attack. The transgenic Bt tomato plants expressing a Cry1Ab protein of B. thuringiensis suffered significantly lower damage by H. armigera than the non-transgenic control plants in the laboratory, greenhouse and field. The Bt plants caused 100% mortality of the larvae and did not support any growth and development by the latter. The only damage caused by the invading neonate larvae was to the terminal parts of tomato shoots, which underwent wilting though larvae died thereafter. In view of this, a complete control of the H. armigera by Bt plants in the field will have to be supported by the other tactics of pest management such as bio-control agents or limited use of pesticides.

The use of composted dry cork, dry-grape marc (fruit residue after pressing) and a 1:1 mixture of dry-olive marc+dry-rice husk as an amendment to potting mixtures was assessed for the management of Meloidogyne species. Amending the potting mixture with composted dry cork at rates of 0%, 25%, 50%, 75% and 100% v/v, reduced the root galling and final populations of Meloidogyne incognita race 1 and M. javanica in tomato, and final nematode population in olive plants, compared with the control. In tomato, increasing the rate of that amendment exponentially reduced the root galling caused by Meloidogyne incognita race 1 (40.8%) and the final nematode population (81.9%). Similarly, increasing rates of the amendment exponentially reduced the root galling of tomato caused by M. javanica (51.3%) and the final population (82.6%). Infection of olive roots by M. incognita race 1 did not cause visible galling; however, amendment with dry cork reduced the final nematode population by 87.9%. Amending the potting mixture with dry-grape marc also reduced the root galling and final populations of M. incognita race 1 and M. javanica in tomato, though the reductions in root galling (24.4% and 25.6%, respectively) and final nematode populations (34.2% and 34.7%, respectively) were not enough for effective nematode management. Root galling and final nematode population were not reduced in potting mixture amended with the 1:1 mixture of composted dry-olive marc and dry-rice husk.

Many gram-negative bacterial pathogens rely on a type III secretion system to deliver a number of effector proteins into the host cell. Though a number of these effectors have been shown to contribute to bacterial pathogenicity, their functions remain elusive. Here we report that AvrPto, an effector known for its ability to interact with Pto and induce Pto-mediated disease resistance, inhibited the hypersensitive response (HR) induced by nonhost pathogen interactions. Pseudomonas syringae pv. tomato T1 causes an HR-like cell death on Nicotiana benthamiana. This rapid cell death was delayed significantly in plants inoculated with P. syringae pv. tomato expressing avrPto. In addition, P. syringae pv. tabaci expressing avrPto suppressed nonhost HR on tomato prf3 and ptoS lines. Transient expression of avrPto in both N. benthamiana and tomato prf3 plants also was able to suppress nonhost HR. Interestingly, AvrPto failed to suppress cell death caused by other elicitors and nonhost pathogens. AvrPto also failed to suppress cell death caused by certain gene-for-gene disease resistance interactions. Experiments with avrPto mutants revealed several residues important for the suppression effects. AvrPto mutants G2A, G99V, P146L, and a 12-amino-acid C-terminal deletion mutant partially lost the suppression ability, whereas S94P and I96T enhanced suppression of cell death in N. benthamiana. These results, together with other discoveries, demonstrated that suppression of host-programmed cell death may serve as one of the strategies bacterial pathoens use for successful invasion.