The aim of this study was to investigate the effect of cationic proportions (K/Ca/Mg) in the nutrient solution on fruit quality (quality attributes and antioxidant content) using a high-pigment, 'Lunarossa', tomato cultivar and a standard tomato cultivar ('Corfù') grown in soilless culture. Treatments were defined by a factorial combination of three nutrient solutions having different cationic proportions and two indeterminately growing round tomato cultivars. A high proportion of K in the nutrient solution increased the quality attributes (fruit dry matter, total soluble solids content) and the lycopene content of tomato fruit, whereas a high proportion of Ca improved tomato fruit yield and reduced the incidence of blossom-end rot (BER). The highest total antioxidant activity was observed in the treatment with a high proportion of Mg in the Lunarossa cultivar. The high-pigment hybrid has provided a higher antioxidant content (lycopene and alpha-tocopherol content) than the commercial hybrid, but it was more susceptible to BER and consequently less productive.

Simple, accurate, and non-destructive methods for determining leaf area (LA) of plants are important for many experimental comparisons. Determining the individual LA of sunflower (Helianthus annuus L.) involves measurements of leaf parameters such as length (L) and width (W), or some combinations of these parameters. Two field experiments were carried out during 2003 and 2004 to compare predictive equations of sunflower LAs using simple linear measurements. Regression analyses of LA vs. L and W revealed several equations that could be used for estimating the area of individual sunflower leaves. A linear equation having W 2 as the independent variable provided the most accurate estimate (r 2 = 0.98, MSE = 985) of sunflower LA. Validation of the equation having W 2 of leaves measured in the 2004 experiment showed that the correlation between calculated and measured areas was very high.Additional key words: Helianthus annuus L.; leaf parameters; non-destructive methods.--Leaf area (LA) is associated with many agronomic and physiological processes including growth, photosynthesis, transpiration, photon interception, and energy balance (Goudriaan and Van Laar 1994). The equation which can predict LA without causing harm to the plant can provide researchers with many advantages in physiological experiments. Moreover, the equations enable researchers to measure LA on the same plants during the plant growth period and may reduce variability in experiments (Serdar and Demirsoy 2006).Despite various techniques used to estimate leaf area (Lu et al. 2004), the most common approach is to develop ratios and regression estimators by using easily measured leaf parameters such as length (L) and width (W; Kvĕt and Marshall 1971). This method usually saves time and is non-destructive. Various combinations of measurements and various equations relating leaf L and W to leaf area have been used in, for example, tomato (Schwarz and We needed a good equation for non-destructive LA estimation for use in physiological and agronomical studies on the vegetative growth phase of sunflower. Therefore, the aims of this study were (1) to compare existing predictive LA equations for sunflower leaves using non-destructive measurements; and (2) to assess the accuracy of the optimum equation selected using an independent dataset. Sunflower (Helianthus annuus L., cv. Melody) leaves used for all measurements and estimations were from two field experiments conducted during 2003 (May-September) and 2004 (May-October) at Tal Amara Research Station in the Bekaa Valley of Lebanon (33°51'44''N, 35°59'32''E, 905 m a.s.l.). The plants were grown in a completely randomized block design with 4 replications. The size of each plot was 3×10 m. Row spacing (four rows) was 0.80 m and the distance between plants in the row was 0.20 m providing a sowing density of 6 plants per m 2 . In both experiments, fertilizer was applied before seeding at a rate of 300 kg ha -1 of NPK (15-15-15). Additionally, 150 kg ha -1 of ammonium nitrate (34N) and 50 kg ha -1 of potassium n...

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Accurate and nondestructive methods to determine individual leaf areas of plants are a useful tool in physiological and agronomic research. Determining the individual leaf area (LA) of small fruit like raspberry (Rubus idaeus L.), redcurrant (Ribes rubrum L.), blackberry (Rubus fruticosus L.), gooseberry (Ribes grossularia L.), and highbush blueberry (Vaccinium corymbosum L.) involves measurements of leaf parameters such as length (L) and width (W) or some combinations of these parameters. A 2-year investigation was carried out during 2006 (on seven raspberry, seven redcurrant, six blackberry, five gooseberry, and two highbush blueberry cultivars) and 2007 (on one cultivar per species) under open field conditions to test whether a model could be developed to estimate LA of small fruits across cultivars. Regression analysis of LA versus L and W revealed several models that could be used for estimating the area of individual small fruit leaves. A linear model having LW as the independent variable provided the most accurate estimate (highest R 2, smallest mean square error, and the smallest predicted residual error sum of squares) of LA in all small fruit berries. Validation of the model having LW of leaves measured in the 2007 experiment coming from other cultivars of small fruit berries showed that the correlation between calculated and measured small fruit berries LAs was very high. Therefore, these models can estimate accurately and in large quantities the LA of small fruit plants in many experimental comparisons without the use of any expensive instruments.

This study was conducted to evaluate the antioxidant properties, including phenolics, ascorbic acid and carotenoids of four green asparagus (Asparagus officinalis L.) spears cultivars (UC 157, AM 822, Gijnlim, and Grande) grown under greenhouse conditions and to asses their changes during cooking process. The highest spear production of category 'extra' and 'first' was recorded on 'UC 157', whereas the higher production of ''second'' class spears was recorded on 'UC 157' and 'Gijnlim'. The Grande cultivar has provided a higher total phenol, quercetin, rutin and lutein + zeaxantin contents in comparison to 'UC 157', 'Gjinlim' and 'AM 822' cultivars. The results also indicate that the effect of cooking process was significant and more pronounced than the effect of cultivars. The cooking process increased the antioxidant activity, total phenols, quercetin, rutin, b-carotene and lutein + zeaxantin contents by, 16%, 23%, 98%, 32%, 24% and 25%, respectively, but decreased the total ascorbic acid content by 52%.

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The genetic modification in fruit and vegetables could lead to changes in metabolic pathways and, therefore, to the variation of the molecular pattern, with particular attention to antioxidant compounds not well-described in the literature. The aim of the present study was to compare the quality composition of transgenic wheat ( Triticum durum L.), corn ( Zea mays L.), and tomato ( Lycopersicum esculentum Mill.) to the nontransgenic control with a similar genetic background. In the first experiment, Ofanto wheat cultivar containing the tobacco rab1 gene and nontransgenic Ofanto were used. The second experiment compared two transgenic lines of corn containing Bacillus thuringiensis "Cry toxin" gene (PR33P67 and Pegaso Bt) to their nontransgenic forms. The third experiment was conducted on transgenic tomato ( Lycopersicum esculentum Mill.) containing the Agrobacterium rhizogenes rolD gene and its nontransgenic control (cv. Tondino). Conventional and genetically modified crops were compared in terms of fatty acids content, unsaponifiable fraction of antioxidants, total phenols, polyphenols, carotenoids, vitamin C, total antioxidant activity, and mineral composition. No significant differences were observed for qualitative traits analyzed in wheat and corn samples. In tomato samples, the total antioxidant activity (TAA), measured by FRAP assay, and the naringenin content showed a lower value in genetically modified organism (GMO) samples (0.35 mmol of Fe (2+) 100 g (-1) and 2.82 mg 100 g (-1), respectively), in comparison to its nontransgenic control (0.41 mmol of Fe (2+) 100 g (-1) and 4.17 mg 100 g (-1), respectively). On the basis of the principle of substantial equivalence, as articulated by the World Health Organization, the Organization for Economic Cooperation and Development, and the United Nations Food and Agriculture Organization, these data support the conclusion that GM events are nutritionally similar to conventional varieties of wheat, corn, and tomato on the market today.

A greenhouse experiment was carried out to determine the effect of cationic proportions (K, Ca, Mg) in the nutrient solution on carotenoids and α-tocopherol content at green–orange, orange, red, and intense-red ripening stages using a high-pigment tomato (Lycopersicon esculentum Mill.) cultivar hp (`Lunarossa') and a standard cultivar (`Corfù') grown in a soilless culture. The highest lycopene concentration was observed in the `hp' cultivar at the red and intense-red ripening stages (3.0 mg/100 g fresh weight and 3.2 mg/100 g fresh weight respectively). In both cultivars, the concentration of β-carotene increased during the ripening stages, reaching the highest value (0.6 mg/100 g fresh weight) at the intense-red stage. The hp cultivar has guaranteed higher lycopene (average, 2.0 mg/100 g fresh weight vs. 1.7 mg/100 g fresh weight) and α-tocopherol contents (average, 1.2 mg/100 g fresh weight vs. 0.9 mg/100 g fresh weight) than those of the standard. In both cultivars, a high proportion of K in the nutrient solution increased antioxidant concentration β-carotene and especially lycopene) during the red and intense-red ripening stages, followed by Mg. The lowest values were recorded for the Ca treatment. Lastly, a positive correlation was recorded between fruit tissue K and lycopene content, whereas a negative correlation was observed between fruit tissue Ca and lycopene content.