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Abstract

The research was focused on the identification of interactions between hypochlorite used as a disinfectant for a recirculating tomato production system and the spread of microorganisms, plant characteristics and fruit quality. Potassium hypochlorite (1% KCLO) supplemented once a week for 90 min into different nutrient solution ranks until a free chlorine concentration of 1 mg L-1 (DI) and 2 mg L-1 (DII) caused benefits but also hazards. Results showed that microorganisms were suppressed by up to 100%. Plants exposed to treatment DI showed a comparable plant height in comparison to control plants, whereas this plant parameter was significantly increased by 12 cm caused by treatment DII after a growing period of seven weeks. However, the formation of leaves was more pronounced by treatment DI. This was obviously the main reason for an increase in yield by 10% (DI) calculated in comparison to control plants. While phytotoxic problems can be excluded, the chlorate (ClO3-) content in tomatoes increased from 0.01 mg (control) to 0.22 mg (DI) and 0.25 mg (DII) ClO3- kg-1 fresh weight. This enhancement should be seen as critical value because new maximum residue levels (MRL) will be defined next year. The levels of lycopene increased with increasing concentrations of hypochlorite as well, which was probably based on a stress response owing to the accumulation of chlorate. Apart from the ClO3- accumulations in fruit, treatment DI represents the most promising disinfection for recirculating tomato production systems.

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Dissolved chemical compositions in rainwater have provided valuable information on pollutant sources in the atmosphere and short-term environmental changes. However, baseline chemical data associated with typhoon is rather limited. In this study, a suite of time-series rain specimens including four typhoon events are collected from Tainan city, southern Taiwan and analyzed for major ions, heavy metals and Pb isotopes to elucidate mechanisms causing dissolved components variation in rainwater and to understand how heavy metals are transported by air-mass along typhoon pathways.Being different from previous views, dissolved major ions and heavy metals in typhoon rains show high concentration and large variability compared with normal period. In particular, dissolved Ni, Cu and Pb change more than several hundred times during typhoon events. This agrees with a scenario that typhoons disturb surface environments and enhance particles scavenged from anthropogenic sites along air-mass pathways. The 206Pb/207Pb ratios are significantly low in high Pb contents specimens, which are mostly associated with high precipitation and confirm local anthropogenic sources due to intense water–particle interaction. In particular, the Cu and Pb fluxes increase > 10,000 and > 10,000,000 times respectively during typhoon events and thus impact importantly the chemical budgets of these metals in coastal ocean. Combining backward trajectories and PCA results demonstrates consistently that air–mass routes dictate critically the dissolved chemical characteristics in rains; furthermore, it highlights the importance of migration pathways to heavy metals distribution in typhoon rainwater.
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Lycopene is a potent antioxidant found in watermelon, tomato, and red grapefruit and may exert positive effects on human health. Spectrophotometric and HPLC techniques are commonly employed for analysis of lycopene content in food sources. A rapid and inexpensive spectrophotometric assay for lycopene is presented. This method requires 80% less organic solvents for release and extraction of lycopene from watermelon than do the existing procedures. Comparative analyses for 105 watermelons from 11 cultivars yielded results equivalent to those provided by larger-volume spectrophotometric assay procedures. Limited numbers of assays suggest that this reduced volume method may be applicable for tomatoes and tomato products.
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This is book 13 in the Crop Production Science in Horticulture series and gives up to date and compact knowledge of the scientific principles underlying the biology and production of the tomato crop. Our understanding of tomatoes has increased and new areas have been developed, such as genetic modification and biological pest control. This book, as others in the Crop Protection Science in Horticulture series, describes the scientific principles underlying the biology and production of the crop. It is worldwide in scope and is written by authors from North America and the Netherlands.
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A spontaneous sweet orange (Citrus sinenesis [L.] Osbeck) mutant 'Hong Anliu' is of high value due to lycopene accumulation in the pulp. In this study, we analyzed the proteomic alterations in the pulp of 'Hong Anliu' versus its wild type (WT) at four maturing stages by using 2-DE combined with MALDI-TOF-TOF MS. Among the 74 differentially expressed proteins identified, the majority are predicted to be involved in stress response, carbohydrate/energy metabolism and regulation, or protein fate, modification and degradation. Particularly, expression levels of six anti-oxidative enzymes were altered by the mutation; and assays of their respective enzymatic activities indicated an enhanced level of oxidative stress in 'Hong Anliu', implying a regulatory role of oxidative stress on carotenogenesis. This conclusion was further confirmed by our observation that treatment of fruit pulps with tert-butylhydroperoxide (a ROS progenitor) induced lycopene accumulation in 'Hong Anliu' only. Gene expression showed that genes predicted to function upstream of lycopene biosynthesis were generally upregulated in juice sacs, but downregulated in segment membranes in both 'Hong Anliu' and its WT. The result suggests an important role of post-transcriptional regulation on carotenogenesis since lycopene was induced in 'Hong Anliu' but not WT. The result also implies that carotenogenesis in juice sacs and segment membranes of citrus fruits may be regulated by different mechanisms.
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We conducted an epidemiological study in Liguria, Italy, on the association between somatic parameters at birth and drinking water disinfection with chlorine dioxide and/or sodium hypochlorite. Over 2 years (1988-1989), 676 births at two public hospitals, one in Genoa (548 cases) and another in Chiavari (128 cases) were examined and data regarding both mother and child were obtained from hospital records. Results indicate a higher frequency of small body length (< or = 49.5 cm) and small cranial circumference (< or = 35 cm) in infants born to mothers who drank water treated with chlorine compounds. In particular, the statistical analysis (by simultaneous variance analysis and Scheffé test) indicated that there may be an association between infants with smaller body length and mothers who drank water treated with chlorine dioxide [adjusted odds radio (OR) = 2.0; 95% CI = 1.2-3.3] or sodium hypoclorite (adjusted OR = 2.3; 95% CI = 1.3-4.2) and between infants with smaller cranial circumference and mothers who drank water treated with chlorine dioxide (adjusted OR = 2.2; 95% CI = 1.4-3.9) or sodium hypochlorite (adjusted OR = 3.5; 95% CI = 2.1-8.5). The presence of neonatal jaundice is almost twice as likely (adjusted OR = 1.7; 95% CI = 1.1-3.1) in infants whose mothers drank water treated with chlorine dioxide.
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