Tomato quality factors such as size, firmness, colour, taste and nutritional content are important criteria for marketing of tomato fruit. The aim of present study was to evaluate the effects of different types of varieties and cultivation technologies (forcing, open-field with supporting system, open-field with processing varieties) on the ingredient content of tomato fruit. The soluble solids (°Brix), carbohydrate, organic acid, lycopene and ascorbic acid contents were measured. Average soluble solids content ranged from 5.2 to 8.7%. The highest °Brix was observed in the fruits of a cherry type tomato, namely Favorita (8.7%). Carbohydrate content constitutes nearly 50% of the °Brix. The highest carbohydrate content was observed for Favorita and Cheresita (both cherry type tomatoes), whereas the lowest was detected in Falcorosso, a processing variety. Low acid content was found in Nívó and Delphine F
cultivars (processing and eating variety, respectively). The sugar-acid ratio was 40% higher in the case of cherry type tomatoes than in the other varieties. Average lycopene content of examined tomato varieties turned out to be extremely diverse (48–134 mg kg
). Ascorbic acid levels did not differ so much, ranging from 226 to 381 mg kg
. In case of open-field cultivation with supporting system, cherry type varieties showed significantly higher °Brix and carbohydrate content than those of round tomato type with average fruit weight of 100∓130 g. All varieties examined produced significantly higher organic acid content in forcing as compared to the values of round tomato varieties cultivated in open-field with supporting system and processing varieties. Lycopene content of tomato fruits from greenhouse was higher than that of fruits from field. Processing varieties yielded significantly higher lycopene content than the others.
Authors:L. Helyes, L. Helyes, Z. Pék, Z. Pék, B. McMichael, and B. McMichael
The snap bean is a significant food crop. Under the Hungarian climate conditions, the supply of raw material of good quality and appropriate quantity to canning factories can be ensured only with irrigation. The present paper evaluates the result of irrigation experiments carried out on snap beans sown in spring and summer and grown with and without irrigation. The experiments were run over the course of 12 years. In the average of 12 years, the yield was 2.8 t ha-1 for spring-sown and 1.9 t ha-1 in summer-sown plants without irrigation. The lowest level of profitable production, the 5.5 t ha-1 was reached twice in the case of spring-sowing and only once in the case of summer-sowing. Profitable yield production can be ensured only with regular irrigation and thus the yield may be increased by 4-5 times. In four of the twelve years we determined the canopy surface temperature of snap bean stands with and without irrigation. A Raynger II infrared remote thermometer determined the canopy surface temperature each day at 13.00 hours. The canopy temperature can well characterise the water supply of plant stands. This parameter may be used for describing the degree of drought and the water turnover of plant stands with different water supply. The positive values of foliage-air temperature differences (SDD) numerically express the degree of drought and the water supply of the crops. The results indicated that a 1 °C higher SDD value might cause 90-130 kg ha-1 yield loss. The method can be useful for investigation of drought affected natural vegetation responses also.
Authors:Z. Pék, H. Daood, A. Lugasi, L. Fenyvesi, and L. Helyes
Quantification of red pigment content of fruits using destructive techniques is expensive and it enables only the analysis of batches but not of individual items. This study examined the feasibility of using non-destructive, spectrophotometric method to predict one of the most valuable internal quality indices, lycopene, in individual tomato fruits. An open field experiment was conducted to study the effect of irrigation and potassium supplementation on the yield and lycopene content of processed tomato fruit. Three different treatments (regularly irrigated RI, irrigation cut-off 30 days before harvest CO, and rainfed RF unirrigated control) and two different potassium fertilisations (P) were applied. Regular irrigation significantly decreased the lycopene content of tomato fruits. The CO treatment resulted in the highest total lycopene without potassium supplementation. Potassium supplementation, given at the time before fruit maturity, significantly increased the lycopene concentration of cultivar Brigade F1, independently of irrigation. The closest correlation was at 700 nm R2=0.38 and R2=0.45, between reflectance and the (all-E)-lycopene and the (9Z)+(13Z)-lycopene isomers, respectively.
Authors:L. Helyes, A. Lugasi, Á. Pogonyi, and Z. Pék
Lycopene, found primarily in tomatoes, is a member of the carotenoid family and has potent antioxidant capability. The aims of the present study were: 1) to investigate the effect of grafting on lycopene content of tomatoes and 2) to evaluate the effects of different varieties on lycopene content (open-field with supporting-system, open-field with processing varieties) under the same ecological conditions. The effect of grafting on lycopene content was analysed in the case of two varieties, between the years 2001 and 2003. Lycopene content of tomato fruits decreased significantly by grafting. Ten commercial varieties of tomato produced in Hungary were examined for their lycopene content. Lycopene content of tomato turned out to be extremely diverse, and variable (63.0–155.0 mg/kg fresh weight). It was found that the variety of tomato is one of the most important determinants of lycopene content.
Authors:Á. Pogonyi, Z. Pék, L. Helyes, and A. Lugasi
Soil-born diseases often cause problems in vegetable forcing; this is because growers use greenhouses for the longest time possible. During the years several solutions have been found to displace chemical control. Grafting is a possible chemical free solution that shows several changes in plants thanks to the vigorous rootstock. In this study we examined the effect of grafting on the yield and fruit characteristics in tomato cultivar. Lemance F1was used as scion and Beaufort as rootstock. Earliness, total yield, fruit weight and number of each graft combination were recorded. Moreover, the main fruit components such as Brix°, carbohydrate, acid and the carbohydrate/acid ratio were analysed. We harvested more yield from the grafted plants. The increase of yield was mainly caused by higher average fruit weight. Brix° and carbohydrate content were lower in the fruits on grafted plants than on ungrafted ones but there was no significant difference in acid content.
Recently several studies have focused on the antioxidant activity of lycopene such as quenching of singlet oxygen and scavenging of peroxyl radicals. These properties may play a role in the prevention of different cancer and heart diseases. Tomato is one of the most important sources of lycopene. The main information on the effect of environmental parameters on quality and health-retaining constituents of tomato fruit is mostly related to temperature (air- and fruit canopy temperature) and light effects that might provide a stress to the fruit. Nowadays little is know about the direct effect of elevated CO2.The aim of the present work was to evaluate the effects of elevated CO2 in Perspex open top chambers (OTC) on the lycopene content of tomato fruit.Experiments on the effects of elevated CO2 concentrations showed mixed results. In this work it was found that concentrations of lycopene in a fruit decreased significantly when elevated CO2 was used. Elevated nitrogen sources generated only slight, but not significant difference in the lycopene concentration of tomato fruit.
Authors:L. Helyes, A. Lugasi, A. Neményi, and Z. Pék
A two-year open field experiment was carried out to study the effect of elevated carbon dioxide (CO2) and nitrogensupply on fruit components of tomato. Korall determinate growth type processing tomato cultivar plants were planted and cultivated for the entire growing season in open top chambers (OTC) in years 2007 and 2008. Compared with the control (350 ppm) CO2 enrichment (700 ppm) significantly decreased the lycopene content at all three harvest dates in both years, but higher supply of nitrogen and 700 ppm CO2 resulted in significantly higher lycopene values in second year. Elevated nitrogen concentration combined with 700 ppm CO2 significantly increased the ○Brix, sugar content, total phenolics, and total antioxidant status (TAS) of tomato fruits.