Showing 14 results for Tomato
A. Alizadeh, A.g. Ghorbani, G.h. Haghnia,
Volume 4, Issue 4 (1-2001)
Abstract
In order to compare the effect of drip and furrow irrigation methods with different quantities of water (50%, 75%, and 100% of the amount of water evaporated from class A pan evaporation during irrigation intervals) on yield and quality of tomato, an experiment was conducted on a silty loam soil in Mashhad Agricultural Research Station. The experimental design was a factorial trial with completely randomized blocks and. four replications.
The results showed that the highest yield (51 t/ha) was obtained from the treatment of drip irrigation with 100% water application. This amount was 4.5 tons higher than the yield from furrow irrigation treatment. Deficit irrigation by 25 and 50 percent decreased total yield by 34.7% and 67.95% in the drip irrigation method and by 27.57% and 64.29% in the furrow irrigation, respectively. Water use efficiency in drip irrigation was two times higher than that in the furrow treatment. Quality and chemical composition of the fruits were not significantly different in the two irrigation methods. Increasing the water deficit, however, increased the amount of soluble solids of the fruits.
M. Niknejad Kazempour,
Volume 6, Issue 1 (4-2002)
Abstract
Pseudomonas syringae is a phytopathogenic bacterium with a wide host range. The biology of this bacterium consists of two phases. The first phase is the indication of disease on the host plant which generally appears in the form of necrosis on the aerial parts of plant (pathogenicity phase). The second phase is a rapid multiplication of bacteria on the aerial surface of the plant without inflicting any defense response (epiphytic phase). In this study, the impact of pathogenic virulence genes of aggress, dsp, ice, cor and hrp genes in the epiphytic process of Pseudomonas syringae on resistant and sensitive varieties of tomato is examined. The population dynamism of bacterial colonization on the root, stem and leaves was studied.
The results indicated that the hrp genes system (hypersensitive reaction and pathogenicity) in Pseudomonas syringae pv. tomato, P. s. pv. syringae and P. s. pv. phaseolicola and the coronatine gene system in P. s. pv. tomato are necessary for colonization on both host and non-host plants. The mutants isolates of hrp and cor compared with wild isolates could colonize at a lower level on all parts of the plant. In contrast, the ice (Ice nucleation), aggress (Agressivity) and dsp (disease specific) gene systems had no significant impact on the epiphytic colonization of P. s. pv. syringae. However, under in vitro conditions no significant difference was observed among the wild type isolates and their mutants in king B medium in the bioscreen machine. It is concluded that the lower multiplication of P. syringae mutants in planta is due to the plant-bacteria interaction.
M. Mazhari, S. Yazdani,
Volume 7, Issue 2 (7-2003)
Abstract
Studies on benefits from innovations (technical change) have mostly been performed within the framework of competitive markets. These studies indicate that if the market structure under study is not competitive, determination of technical change benefits within a competitive framework may yield distorted or biased results for different groups. Considering the noncompetitive market structure of tomato in Khorasan Province, benefits from applying biological innovation for farmers, processors and the society as a whole were estimated.
The results indicate that under noncompetitive conditions in the tomato market in Khorasan Province, and as a result of the processors’ market power in buying tomato, the potential benefits of utilizing hybrid varieties have reduced for both farmers and the society by about 58 and 12.5 percent, respectively. It may naturally be concluded that farmers’ incentives to adopt hybrid varieties are attenuated because of the tomato noncompetitive market.
A. H. Elahami Rad, F. Shahidi,
Volume 8, Issue 1 (4-2004)
Abstract
Bulk tomato paste is produced in concentrations higher than 35% (350 Brix scale) and its packaging is not hermetic. In recent years, the production of this product in our country has considerably increased. One of the most important problems in the tomato paste industry of Iran is the preservation of bulk tomato paste. Shelf-life of tomato paste depends on many factors such as initial quality of tomato paste, cooling conditions, salting, packaging, handling, and cold storage. The product factors evaluated in this study included: 1) microbial parameters such as total count, acid-resistant microorganisms, and Howard Mould Count and 2) physico-chemical parameters such as acidity, pH, amount of lactic acid (D and L forms), and total dry matter.
Experimental data showed that using high brix (35-38) in producing tomato paste along with salting the product surface and storing it at 0 ºC had only a limiting effect on microbial changes and could not prevent their growth completely. However, salting treatment had a great effect on surface growth of fungi and their ability to produce colonies and mycelia. On the basis of the results obtained from this study, cooling of bulk tomato paste in ambient temperature is critical to bulk tomato paste production process and also has an important effect on the quality and shelf-life of the product.
M. R.edalatian, S. A. Mortazavi, M. Hamedi, M. Mazaheri,
Volume 9, Issue 4 (1-2006)
Abstract
Production and consumption of whole tomato and/or its products(tomato paste, tomato juice, ketchup, etc) is incearsed all over the world. Annual production of tomato in Iran is about 3.4 million tons (MT), part of that is processed in the tomato paste factorise, which are mostly located in khorasan province. Since tomato variety has a determinant effect on the physico-chemical and organo leptical properties/quality of tomato and its products, an investigation was performed to evaluate the impact of variety and storage time of four tomato varieties, Cal.j.n.3, Early Urbana Y, Early Urbana 111and Peto early C.H which were selected according to a national project and were monitored according to their brix, pH, Acidity, Sugar and Salt contents, total and non soluble solids. Results indicated that Early Urbana 111 and Peto early C.H contained the highest amounts of soluble solids along with the highest pH. Also it was evidenced that these varieties were the most stable varieties as the least compositional changes was seen in them.
M. Kh. Pirouzi Fard,
Volume 10, Issue 2 (7-2006)
Abstract
In the present study, the effects of sodium metabisulphite concentration (2, 4, 6, 8, 10%), dipping time (2.5, 5.0, 7.5, 10 min.) mixing of the solution including: continuous mixing , once per 2.5 minutes , once per 5.0 minutes and without mixing (I, II, III, IV) and pH of the solution (4.62, 3.62, 3.42) on the absorption of sulphure dioxide by halved Riogrande variety tomatoes prepared for sun drying were investigated. The experiment design was completely randomized plots with the order of 5, 4, 4 and 3 treatments, each with four replications. The results showed that increasing the solution concentrations, dipping time, mixing and decreasing pH increased the rate of SO2 absorptions. The increment of SO2 in tomato under the effect of the above mentioned factors have been shown in different tables and figures. The mathematical models of relationship among the rate of absorption of SO2 , the concentration of sodium metabisulfite solution, dipping time, also the effect of metabisulfite solution pH were developed. Significant differences were found in these increments in all the treatments (α= 0.01).
E. Khanipour, J. Keramat, R. Shokrani,
Volume 11, Issue 40 (7-2007)
Abstract
Producing food colors from natural sources, such as tomatoes, which could be used instead of synthetic colors, is important in relation to health and safety aspects of the consumers. In this research, solvent extracting was carried out by using three non-polar solvents, including petrolium ether (bp=55°C), n-hexane (bp=60°C) and a mixture of n-hexane: ethanol: aceton (1:1:2, bp=50°C). Also, two different temperatures (room temperature and boiling point of the solvent) and three different periods of time (2,4 and 6 hours) of extraction were tried. Using mixture of the solvents (at boiling point) for six hours showed to be the optimum conditions for extraction and there were significant differences between this treatment and other conditions for extractions. In addition to the above results, the same volumes of the solvent and samples were found to be the best ratio in comparison with the other volumes ratios. It was significant at P .05.. The yield of color extraction from tomatoes and tomato powder was 0.14 and 0.24% (w/w), respectively. Also, the purity of the extracted color was 82.65% lycopen. The extracted color showed a good stability in sunflower oil for three months at 4°C.
N. Sahebani, N. Hadavi,
Volume 12, Issue 43 (4-2008)
Abstract
This research was conducted to study the effect of nematode (Meloidogyne javanica) on severity of tomato Fusarium wilt (Fusarium oxysporum f.sp. lycopersici race 1) and changes in Phenylalanine ammonia lyase (PAL) activity in split-root assays to show the possibility of systemic induced susceptibility caused by nematode to the fungus by local nematode infection. The results showed that the activity of nematode in one part of root confered susceptibility to Fusarium wilt in other part of the plant root and subsequently disease symptoms increased significantly in comparison to the control (without nematode inoculation). PAL specific activity showed a significant decrease in one half of split-root inoculated with fungus when the other half was inoculated with nematode as compared with the control (without nematode inoculation). Based on the results obtained in this study, nematode infection in one part of tomato plant root resulted in suppression of tomato defenses in all parts of the root, reduced tolerance or resistance to the fungus (as secondary pathogen) and intensified the fungal disease.
A. Chakraei, J. Pourreza, A. Tabeidian,
Volume 12, Issue 43 (4-2008)
Abstract
This experiment was carried out to determine the nutritional value and the effect of different levels of tomato seed and pomace on performance of broilers. Corn grains and soyabean meals were replaced by tomato seed at levels of 6, 12 and 18 % and tomato pomace at levels of 3, 9 and 12 %. At first, the metabolizable energy of tomato seed and pomace was determined by the Sibbald method. In this experiment, 504 commercial broiler chicks (Ross 308) were used for 8 weeks (from 7 to 56 days old ) in a completely randomized design in 7 treatments with 4 replications per treatment. After 21 days, protein digestibility of the ration in illeum was determined. Apparent metabolizable energy was 3394 kcal/kg for seed and 2329 kcal/kg for pomace and crude protein was 31, 22.7, respectively . The result showed that body weight, protein digestibility of rations in illeum and carcass characteristics were not significantly different . Best energy and protein conversion efficiencies were obtained at the level of 6 % seed and 9 % pomace, that were not significantly different from control treatment. Cheeks fed with seed and 12% tomato pomace had significantly (p<0.5) higher feed intake than control group.The difference between diets containing 6% seed and 3% pomace and control group was not significant regarding feed conversion ratio.
Gh Mesbahi, A Abasi, J Jalali, A Farahnaki,
Volume 13, Issue 47 (4-2009)
Abstract
In this research, tomato peel and waste seed obtained from tomato paste processing were dried and milled. The obtained powder was added to tomato ketchup sauce in different proportions (1, 2, 5, 7 and 10%). To study the effect of tomato peel and seed powder on physicochemical and nutritional properties of the tomato ketchup samples, the parameters including lycopen, total solid, brix, total sugars, reducing sugars, protein, fat, ash, fiber, vitamin C, pH, color (L, a/b) were evaluated. Rheological properties of the ketchup samples (consistency and viscosity) were determined and compared with control samples. Sensory evaluation of the ketchup samples was carried out after 1, 2 and 5 months of storage by a group of panelists. Addition of tomato peel and seed powder resulted in an increase in total solid, brix, ash, fiber, protein, fat, consistency and viscosity of the ketchup samples. Sensory evaluation tests did not show any significant difference between the color, flavor, texture and overall acceptability of the control and samples containing 1 or 2 % of tomato peel and seed powder. In addition, sensory evaluation tests did not show any significant changes in the ketchup samples during storage. Thus, it can be concluded that nutritional and rheological properties of tomato ketchup can be improved by addition of tomato peel and seed powder.
A Akbari, M Shahedi, N Hmadami, Sh Dokhani, M Sadeghi,
Volume 13, Issue 47 (4-2009)
Abstract
Sun drying is a well-known food preservation technique that reduces the moisture contents of agricultural products. Shrinkage, rehydration ability and color of food materials during air drying adversely affect the quality of the dried products. Since all fresh tomatoes can not be consumed at the time of harvest, preservation provides a larger market, allowing consumers to buy the preserved tomato through the year. A natural convection solar dryer consisting of a solar air heater and a drying chamber was manufactured in this research. Tomato slices were dried in the solar dryer and compared with open sun drying. Also, tomato slices were dried in a laboratory oven (operated at temperature 50, 60, 70, 80°C). With increasing the temperature, the time required to arrive certain moisture content is decreased. Also results showed that drying time in the solar dryer is shorter than open sun drying. In other words, drying time was reduced 17 to 45% by the solar drying in comparison to open – sun drying. The experimental shrinkage data showed a linear behavior with moisture content. Also, the experimental data didn't show a strong effect of temperature on the rehydration ability of the product. Thus, the effect of temperature and method of sun drying on the shrinkage phenomenon and the rehydration ability can be neglected. Tomato slices dried at 50°C had better appearance (lightness and red color) than at 80°C.
Shahinrokhsar , Shokri , Asadi, Davari, Peyvast,
Volume 14, Issue 53 (10-2010)
Abstract
Nowadays in the world, soilless culture as a kind of technique is known to give vegetable crops higher yield and quality. This experiment was conducted at research greenhouse of Agriculture and Natural Research Center of Golestan province in spring 2005. The purpose of this research was to investigate the effects of irrigation frequency and substrates on yield and fruit quality of greenhouse tomato (CV. Hamra). Irrigation was carried out for 4, 8 and 12 times a day. The substrates were Perlite, Leca and Perlite + Leca (1:1, w/w). The experimental design was factorial in the form of randomized complete design with four replicates. The substrates used in the experiment had no effect on most factors. However, TA (0.43 mg/100 l) and fruit set (48%) were increased significantly by perlite and Leca substrates, respectively. The results indicated that higher and lower marketable yields were obtained from plants irrigated 12 (1830.5 g/plant) and four times (1156.7 g/plant) per day, respectively. Also increasing irrigation schedule decreased the Titratable acidity but didn't significantly affect the other factors. According to these results, Irrigation of 12 times per day and Leca substrate increased vitamin C and marketable yields, leading to optimum quality and quantity fruit set and the decreased TA (0.33 mg/100 l) in fruits in this treatment.
A. Mohammadkhani, M.r. Nouri Emamzadeh, A. Mirjalili,
Volume 17, Issue 66 (2-2014)
Abstract
Four partial root zone drying (FULL, 1PRD50, 2PRD50, 3PRD50) treatments were investigated on tomato characteristics and water use efficiency using completely randomized design with five replications. In the control treatment (Full irrigation), all water requirement of plant was met in the root area equally during the growing season. Roots in 1PRD50, 2PRD50 and 3PRD50 treatments were divided into two equal parts and each side of root was irrigated one, two and three times, respectively. Results showed that the highest (44.43 g) and lowest (24.57g) tomato mean weights were obtained at full irrigation and 3PRD50, respectively. Maximum of diameter (43.1 ml) and fruit number (46 No) was observed in the control and minimum of these traits (15.6 ml and 20 No, respectively) was observed in 3PRD50 treatment. There was a highly significant difference between fruit number in all treatments. Highest yield and marketable yield was obtained in the control and 1PRD50 treatment, respectively. The highest irrigation water use efficiency was obtained in 1PRD50 (48 percent more than the control) and the lowest value was in 3PRD50 (27 percent lower than the control). Based on results of this study, partial intermittent irrigation (1PRD50) is recommendable for tomato production.
A. Abdolahi Arjenaki, A. A. Fadaei Tehrani,
Volume 19, Issue 71 (6-2015)
Abstract
Plant parasitic nematodes, especially root knot nematodes, cause damage to most of agricultural products, and many efforts have been done to control them. In recent years, application of industrial waste and wastewater sludge as organic fertilizers in agriculture has been increased. To investigate the effects of sewage sludge on root knot nematode pathogenicity in tomato, different weights of sewage sludge (0, 4, 8, 15 and 25% of sludge in the soil) in soil were added as a completely randomized design with six replications. Analysis variance and mean comparison of growth indices of plants showed significant effects of treatments. For example, means of stem length of plants increased in soil with more amount of sewage sludge. This relationship was also observed in other indices and nutrients elements. So using sewage increased nitrogen, phosphorous, calcium and magnesium in tomato shoots inoculated with nematodes while the change of potassium was very small. Application of sewage sludge decreased the number of galls, egg-masses and eggs in egg-mass of root knot nematode.
