The influence of the water supply on the bioactive compounds of different tomato varieties

The objective of this study was to investigate the influence of irrigation on the composition and content of phenolic compounds and carotenoids in different tomato cultivars using HPLC/DAD-UV technique and reverse-phase (RP) chromatographic columns for analysis. Among phenols, the quercetin derivatives and hydroxycinnamic acids and their derivatives were the major compounds, while lycopene was the dominant carotenoid in the extract of tomato. It was found that the response of tomatos to shortage of water is affected by genetic factors and seasonal environmental variations. In general, 100% irrigation yielded tomatoes with the lowest level of carotenoids and polyphenols. In 2012, when the temperature and number of sunny hours were at record levels, the non-irrigated plants of cultivar Strombolino yielded tomatoes with significantly higher levels of carotenoids and phenols than that of the other cultivars

Visible reflectance and content of isomeric ratio of lycopene in commercial and elevated lycopene tomato varieties by different technological traits

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

Colour evolution of conventionally and organically cultivated hungarina red spice paprika varieties

Colour evolution of conventionally and organically cultivated Szegedi-20, Meteorit, Mihálytelki and Kármin spice paprika varieties was studied in green, break, pale red, deep red and over-ripened maturity stages. As the ripening stages forwarded the organic samples gradually lost their initial extractable colour (ASTA value) gain toward their conventional counterparts. The over-ripened colour levels were satisfactorily high in the conventional (169.9-264.8 ASTA) and in the organic (160.8-210.5 ASTA) paprika varieties as well, although the colour accumulation was 9.0- 62.8 ASTA lower in the organic samples. Significant and perceptible visual colour differences (ΔE*ab) were found between the organic and conventional crops. The lightness difference (ΔL*) indicated that the organic paprika generally were lighter than the conventional ones. The positive hue difference (ΔH*ab) showed that the colour of deep red and over-ripened organic Szegedi-20, Mihálytelki and Kármin paprika crops were more yellow compared with the conventional group. The lightness (L*) and hue angle (h°ab) were found the most suitable instrumental colour parameters to distinguish the ripening stages and the colour characteristics of the samples. The better colour evolution of conventional crops was attributed to the soil characteristics, nutrient supply and chemical plant protection that were specifically designed for the needs of paprika in the conventional farming

Effect of water supply on sugar concentration of carrot

Carrot is an important source of sugars. The objective of this study was to investigate the effects of water supply (precipitation + irrigation) on the concentration and ratio of fructose, glucose, and sucrose in carrot. Irrigation did not decrease the dry matter content and the summed concentration of the three measured sugars. Glucose accumulation was not influenced either by irrigation or by year. Low amount of precipitation during the early growing period was detrimental for fructose accumulation. Irrigation enhanced sucrose concentration, presumably by ensuring better photosynthetic activity. However, dry and hot weather during the irrigation cut-off period in 2011 also resulted in increased sucrose accumulation, presumably as a stress effect. It was found that irrigation did not influence the ratio of the three investigated saccharides at all, and even the growing year had just a slight effect on that

Effect of water supply on canopy temperature, stomatal conductance and yield quantity of processing tomato (Lycopersicon esculentum Mill.)

Tomato (Lycopersicon esculentum Mill.) is one of the most extensively cultivated horticultural crops in the world.Water supply is important for yield quantity and quality. The aims of the present study were 1) to evaluate the canopy temperature and the stomatal conductance on processing tomato substances with different water supply, 2) to investigate the effect of different water supply on yield quantity. There were two irrigated treatments, one of them was the reguralry irrigated plant stand which got 333 mm water during investigated period, including the precipitation and the other was the cut off substance which means the irrigation (drip) was stopped at the beginning of the ripening process and there was a control as well which got 189 mm precipitation. The canopy temperature was measured row by row with a Raytek MX 4 type infrared remote thermometer. The stomatal conductance was measured by Delta-T AP4 type porometer. There were significant differences between the control and irrigated plants according to the water supply which was formulated the canopy values. The plants with a deficient water supply were decreased the transpiration rate, therefore its cooling effect didn’t show up. The regularly irrigated tomato plants’ yield exceeded the unirrigated ones more than twice. It is emerged from the study that the irrigation has a positive effect on the amount of the harvestable yield in this year type

Effect of water supply on canopy temperature, stomatal conductance and yield quantity of processing tomato (Lycopersicon esculentum Mill.)

Tomato (Lycopersicon esculentum Mill.) is one of the most extensively cultivated horticultural crops in the world.Water supply isimportant for yield quantity and quality. The aims of the present study were 1) to evaluate the canopy temperature and the stomatal conductanceon processing tomato substances with different water supply, 2) to investigate the effect of different water supply on yield quantity.There were two irrigated treatments, one of them was the reguralry irrigated plant stand which got 333 mm water during investigatedperiod, including the precipitation and the other was the cut off substance which means the irrigation (drip) was stopped at the beginning ofthe ripening process and there was a control as well which got 189 mm precipitation. The canopy temperature was measured row by row witha Raytek MX 4 type infrared remote thermometer. The stomatal conductance was measured by Delta-T AP4 type porometer. There weresignificant differences between the control and irrigated plants according to the water supply which was formulated the canopy values. Theplants with a deficient water supply were decreased the transpiration rate, therefore its cooling effect didn’t show up. The regularly irrigatedtomato plants’ yield exceeded the unirrigated ones more than twice. It is emerged from the study that the irrigation has a positive effect on theamount of the harvestable yield in this year type

Simultaneous impact of the different water supply and year type on processing tomato yield

A two year (2008 and 2009) open field experiment was conducted to study the effect of irrigation on the yield parameters and fruit components of processing tomato. Two different treatments were applied: regularly irrigated (RI), irrigation cut-off 30 days before harvest (CO), compared with unirrigated control (RF). The optimal water supply was calculated from average daily temperature. The aims of the study were to investigate the effect of different water supply on yield quantity. The regularly irrigated plant stands gave significantly higher yield, and unirrigated plants showed yield loss.Water supply had strong positive (R2=0.81) effect on marketable yield and average fruit weight (R2=0.78). Linear regression showed, that 46.5 mm more water supply caused 10 t/ha more marketable yield, and 13.4 mm more water supply caused 1 g more in the average fruit weight. The irrigation increased the Brix yield as well

Kinetics of carotenoid degradation in spice paprika as affected by storage temperature and seed addition

The extractable (ASTA) colour retention of four different milled spice paprikas was evaluated at 10, 20, 35, 50, and 60 °C storage temperature. The ASTA colour stability during long-term storage period strongly depended on the temperature, primary handling and drying of the fresh crop, and the applied production technology. The cooled (10 °C) or temperature-controlled (20 °C) conditions appeared to be a reasonable solution to preserve the quality of paprika powder. The kinetics study on the temperature dependence of ASTA colour loss estimated the apparent reaction order, rate constants, predicted half-life times and activation energy. The Q10 approach and shelf life-plot resulted in useful data, which can be suitable for quick and economical evaluation of further spice paprika products