苹果果实中毒死蜱残留的品种间差异及套袋对毒死蜱残留的影响

为探讨苹果果实中毒死蜱残留的品种间差异及套袋对其残留的影响作用,采用气相色谱法（GC-FPD）,研究了不同品种苹果果实中毒死蜱的残留动态以及套袋对苹果果实不同部位中毒死蜱残留的影响。结果表明,毒死蜱在苹果果实中的残留量存在着明显的品种差异,其中红富士属于高农药残留的品种,而嘎拉、红将军和83-1-70-3则属于低农药残留的品种。毒死蜱在苹果果实不同部位中的残留量表现出明显差异,果皮是毒死蜱残留的主要部位,其次是全果,果肉中的残留最少。套袋明显减少了毒死蜱在苹果果实中的残留量,不论处理浓度和取样时间如何,套袋苹果果实中毒死蜱的残留量比不套袋至少减少1/3。     

The persistence and degradation of chlorothalonil and chlorpyrifos in a cranberry bog

The effect of a spray-tank adjuvant on the persistence, distribution, and degradation of two pesticides, chlorothalonil and chlorpyrifos, was studied in a commercial cranberry bog. Pesticides were applied according to label instructions to cranberry plants in paired plot studies. Dislodgeable foliar and whole fruit residues of both pesticides and several degradation products were assessed over a growing season. Residues were also assessed in soil samples collected at fruit harvest. Adjuvant increased both fruit and foliar residues but did not significantly alter the dissipation rate or metabolism of either pesticide. The dissipation of dislodgeable foliar chlorothalonil and chlorpyrifos residues followed first-order kinetics, with estimated half-lives of 12.7 and 3.5 d, respectively. All residue levels on harvested fruit were well below the current U.S. EPA tolerances for fresh cranberries. Chlorothalonil (58%) was the major residue in fruit at harvest (76 d post-chlorothalonil application), with 4-hydroxy-2,5,6-trichloroisophthalonitrile and 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene accounting for 26% and 6% of the total residues, respectively. Degradation products accounted for 88% of the total chlorothalonil residues in soil at fruit harvest. The products 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene, 1-carbamoyl-3-cyano-4-hydroxy-2,5,6-trichlorobenzene, 2,5,6-trichloro-4-methylthioisophthalonitrile, and 2,4,5-trichloroisophthalonitrile have not been previously identified in cranberry bog environments. Chlorpyrifos was detected in fruit at harvest (62 d post-chlorpyrifos application), but no metabolites were found. Chlorpyrifos-oxon and 3,5,6-trichloro-2-pyridinol, however, were detected in earlier fruit samples and in foliage and soil samples.     

Relationship between ethylene response manipulation and volatile production in Jonagold variety apples.

The ripening of Jonagored Jonagold apple fruit (Malus x domestica Borkh.) during development was manipulated with preharvest applications of ReTain or a combination of ReTain plus Ethrel. The fruits, harvested preclimacteric at approximately the same stages of maturity, were stored in refrigerated air (RA) for 45 days or in controlled atmosphere (CA) for 180 days at 0 degrees C. Volatile evolution, ethylene production, and respiration of stored fruit were studied during poststorage holding at 22 degrees C. ReTain reduced volatile production by 19%, but application of Ethrel to ReTain-treated fruit increased production to control levels. The inhibition of volatile production by ReTain appears to be independent of respiration but may be related to the ethylene-producing capacity of the fruit. Although ReTain reduced flavor-related volatile esters, it did not affect levels of the compound responsible for the typical spicy flavor in Jonagored Jonagold fruit, 4-methoxy-2-propenylbenzene. The CA-stored fruit had a much reduced production of volatile compounds compared to RA-stored fruit, with more discernible effects in ReTain-treated fruit. Ethrel application to ReTain-treated fruit improved the volatile production intermediate between the ReTain alone and control in CA-stored fruit. The data collectively suggest that ReTain may have some promise for better scheduling of harvest of apples with no appreciable loss in RA-stored fruit quality. Reduction in production of alpha-farnesene by ReTain may also reduce the potential for scald development in CA-stored fruit.     

Preharvest calcium sprays improve volatile emission at commercial harvest of 'Fuji Kiku-8' apples

Apple (Malus × domestica Borkh.) fruit intended for long-term storage are frequently harvested commercially before becoming fully ripe, often resulting in poor aroma development. Since postharvest calcium dips have proved effective for the enhancement of flavor-related volatile esters after cold storage of apples, this study was undertaken in order to assess whether preharvest calcium sprays (7 weekly applications at 1.6%, w/v, 81-123 days after full bloom) could also aid in improving this important attribute at harvest. This procedure significantly increased calcium content in treated fruit. The emission of aroma-related volatile esters by untreated and calcium-treated 'Fuji' apples was then monitored during maturation and ripening over two months prior to commercial harvest. Results indicate that most of the compounds contributing to overall flavor in ripe fruit were enhanced in response to preharvest calcium applications, suggesting that this procedure may be suitable for the improvement of fruit aroma at harvest. The emission of acetate esters was particularly favored, consistent with higher acetaldehyde contents in treated fruit. These effects arose apparently from increased pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) activities, possibly leading to a better supply of alcohols and acyl CoAs for ester biosynthesis.     

Effect of preharvest application of calcium on the postharvest physiology of apricot fruit

The effect of preharvest calcium (Ca) foliar application on ethylene (C₂H₄) production, respiratory rate, soluble polyuronides, and fruit firmness of ‘Bebekou’ apricot fruits was determined. The study was carried out in two experimental years, 1991 and 1992. Calcium was applied 21, 17, and 13 days before harvest for 1991 at the concentration of 0.5% calcium chloride (CaCl₂) each time and 16 and 12 days before harvest for 1992 at the concentrations of 0.8 and 0.7% CaCl₂, respectively. Calcium treatment resulted in a 30–76% increase in the Ca content of fruit flesh. Treated fruits had significantly lower C₂H₄ production rates than control during (i) four (1991) or five days (1992) at 21°C out of the 7‐day period examined immediately after harvest, and (ii) one (1991) or two days (1992) at 21°C out of the seven‐day period examined immediately after a 3rd‐ (1991) or 4th‐week (1992) storage period at 0°C. After harvest, Ca‐treated fruits displayed one day delay to reach the peak rate of C₂H₄ production. Respiratory rate was significantly suppressed over a five‐day period at 21°C out of the seven‐day period examined immediately after harvesting. However, after four weeks of storage at 0°C, there was not any significant effect of Ca on the respiratory rate. The respiratory peak rate occurred earlier in the control fruits compared to that of the Ca‐treated fruits at harvest time. Calcium‐treated fruits were about 70% firmer than the untreated ones at harvest time. Furthermore, this difference persisted after four weeks of storage at 0°C. Foliar‐applied Ca produced a 29% decrease in the soluble polyuronide content of the fruits at harvest time, but not after four weeks of storage. Fruit firmness was positively correlated to the Ca content of fruits while the soluble polyuronide content of the fruit was negatively correlated to fruit Ca.     

乙酰甲胺磷及其高毒代谢物甲胺磷在白菜中的残留动态

为明确乙酰甲胺磷在叶菜类蔬菜上使用后的环境安全性,采用气相色谱法比较研究了露地与设施栽培条件下乙酰甲胺磷及其高毒代谢物甲胺磷在白菜中的残留动态规律和最终残留。结果表明,按推荐使用剂量、2倍推荐使用剂量施药1次,乙酰甲胺磷在白菜中降解半衰期为2.060～3.203 d,大棚条件下降解速度慢于露地条件下降解速度;乙酰甲胺磷在降解过程中可代谢产生甲胺磷,作物中甲胺磷的残留量是乙酰甲胺磷代谢生成和甲胺磷本身降解两个过程共同作用的结果,施药几天后,出现一个甲胺磷残留的高峰;乙酰甲胺磷施用在白菜上可能会有较高的甲胺磷残留风险,尤其是大棚栽培方式、施药浓度高的情况下使用乙酰甲胺磷具有更高的甲胺磷残留风险。因此,在白菜等叶菜类蔬菜上应谨慎使用乙酰甲胺磷,露地栽培条件下的安全间隔期应延长为21 d,设施栽培条件下不宜使用。     

Residue uptake and storage responses of Tarocco blood oranges after preharvest thiabendazole spray and postharvest heat treatment

Tarocco blood oranges (Citrus sinensis Linn. Obsek) were subjected to a single preharvest spray with thiabendazole (TBZ) at a concentration of 1% active ingredient (ai) in water and harvested 2 weeks after fungicide application or heated at 37 degrees C for 48 h under saturated humidity after harvest. The two treatments were also combined before cold quarantine (3 weeks at 2 degrees C), subsequent storage (3 weeks at 8 degrees C), and simulated marketing period (SMP) (1 week at 20 degrees C). Fruit not treated with TBZ and unheated were used as controls. The residue levels of TBZ (active ingredient, whole fruit basis) after spray were approximately 6.3 and 5.4 mg x kg(-1) before fruit storage respectively, a level close to the tolerance limit set by the European Community. TBZ showed a high persistence during quarantine, storage, and SMP. TBZ spray significantly reduced the incidence and severity of chilling injury (CI) and decay during the postquarantine period and SMP. Heat treatment (HT) produced beneficial effects in controlling CI, especially during SMP, when applied in combination with TBZ. However, HT remarkably promoted the development of secondary fungal infections such as Phytophthora rots and adversely affected fruit flavor and taste. The occurrence of off-flavor and off-taste was found to be perceptible after heating.     

Preformed Biomarkers Including Dialkylphosphates (DAPs) in Produce May Confound Biomonitoring in Pesticide Exposure and Risk Assessment

Low levels of pesticides and their metabolites/degradates occur in produce when pesticides are used in conventional or organic crop protection. Human dietary and nonoccupational urine biomonitoring studies may be confounded by preformed pesticide biomarkers in the diet. The extent of formation of putative urine biomarkers, including malathion specific (MMA, MDA; malathion mono- and diacids), organophosphorus generic (DMP, DMTP, DMDTP; dimethyl-, dimethylthio-, and dimethydithiophosphate), pyrethroid generic (3-PBA; 3-phenoxybenzoic acid), and captan-specific metabolites (THPI; tetrahydrophthalimide), was measured in produce samples containing the parent pesticide. Every produce sample of 19 types of fruits and vegetables contained biomarkers of potential human exposure. A total of 134 of 157 (85%) samples contained more molar equivalent biomarkers than parent pesticide. Malathion and fenpropathrin were sprayed (1 lb/A), and the time-dependent formation of pesticide biomarkers in strawberries was investigated under field conditions typical of commercial production in California. Malathion and fenpropathrin residues were always below established residue tolerances. Malathion, MMA, and MDA dissipated, while DMP, DMTP, and DMDTP increased, during a 20 day study period following the preharvest interval. The mole ratios of biomarkers/(malathion + malaoxon) were always greater than 1 and increased from day 4 to day 23 postapplication. Fenpropathrin and 3-PBA also dissipated in strawberries during each monitoring period. The mole ratios of 3-PBA/fenpropathrin were always less than 1 and decreased from day 4 to day 14. The absorption of pesticide biomarkers in produce and excretion in urine would falsely indicate consumer pesticide exposure if used to reconstruct dose for risk characterization.     

Effect of Preharvest Sprays of Calcium on Cracking and ‘Schattenmorelle’ Sour Cherry Fruit Quality Harvested Mechanically

The aim of the study was to examine effect of preharvest sprays of calcium (Ca) in the form of Ca-chloride (CaCl₂), Ca-nitrate [Ca(NO₃)₂], or a mixture of Ca-formate, Ca-acetate, CaCl₂, and Ca(NO₃)₂ on cracking and quality of ‘Schattenmorelle’ sour cherry fruit harvested mechanically. The experiment was conducted in 2008–2009 at a commercial orchard in central Poland. Mature trees grew on a coarse-textured soil poor in organic matter, at a spacing of 4.0 × 1.5 m. The spray treatments of Ca were performed at 7-day intervals, starting 28 days before harvest, at the rates of 5.0–5.6 kg Ca ha^?1 per season. The trees sprayed with water were treated as the control. Fruit were harvested mechanically when peduncle-fruit detachment force dropped below 3 N. The results showed that preharvest Ca sprays caused no leaf damage. This measure did not affect yield, mean fruit weight, soluble solids concentration and titratable acidity of fruit, and weight loss of fruit during 24 h after harvest. Fruit sprayed with Ca had improved status of this nutrient, and were less liable to juicy leakage from the stem scar, rain-induced cracking, and preharvest decay caused by Glomerella cingulata. The above effects of Ca sprays did not depend on the tested material. It was concluded that preharvest sprays of Ca as CaCl₂ and/or Ca(NO₃)₂ should be recommended in ‘Schattenmorelle’ sour cherry orchards to reduce fruit losses resulting from rain-induced cracking, leakage of juice, and the incidence of cherry bitter rot.     

Determination of fungicide residues in field-grown strawberries following different fungicide strategies against gray mold (Botrytis cinerea)

In a 2 year experiment, residues in field-grown strawberries were investigated from the fungicides fenhexamid, pyrimethanil, tolylfluanid, and kresoxim-methyl resulting from different strategies, as regards the dose, number, and time of fungicide applications. Kresoxim-methyl was only used the first year and in full or no dose to control powdery mildew. In the first year, the highest concentrations analyzed were 0.66 mg kg(-1) for pyrimethanil and 0.63 mg kg(-1) for fenhexamid resulting from the use of recommended dose rates and a preharvest interval (PHI) of 10 days, thus not exceeding the Danish maximum residue limit (MRL) of 1 mg kg(-1). Tolylfluanid was used no later than 21 days before harvest, which left residue contents in the berries of 0.48 mg kg(-1), a value well below the MRL of 5 mg kg(-1). In the second year, fungicide residues found in the samples were generally lower, 0.39 and 0.03 mg kg(-1) for pyrimethanil and fenhexamid, respectively. No residues of kresoxim-methyl were found in any of the samples from the field trials, indicating that kresoxim-methyl residues had declined to a level well below the detection limit within the 28 day period between the last application and the harvest.     

Association of ethylene dibromide (EDB) with mature cranberry (Vaccinium macrocarpon) fruit

Ethylene dibromide (EDB), a potential carcinogen, has been used in gasoline mixtures to avoid the accumulation of metallic lead in engines. Ethylene dibromide is present in the environment and in groundwater. Previous analysis has shown that EDB levels have reached up to 16 microg L-1 in the groundwater at two fuel spill plumes in the vicinity of the Massachusetts Military Reservation (MMR) Base and up to 1.69 microg L-1 in the Coonamessett and Quashnet Rivers in Cape Cod, MA (U.S. Air Force IRP, Fact Sheet #98-10, 1998). Groundwater and river water from this area are used to flood some local cranberry bogs for irrigation and harvesting of cranberry fruits. The potential sorption of EDB by cranberry fruits during harvest has caused concern but information regarding its occurrence is not available. In this study, low levels of EDB (0.04-0.15 microg kg-1) were found to be associated with cranberry fruits that were exposed to EDB at levels ranging from 3 to 12 microg L-1 at 10, 20, and 30 degrees C for up to 7 days. Rinsing EDB-exposed cranberry fruits twice with deionized water or once with 0.01 M NaCl solution reduced the amount of EDB associated with the cranberry fruits by 65-72% to a level of 0.02 microg kg-1. Therefore, the EDB most likely is associated with the water residue on the surface of the cranberry fruit rather than being absorbed into the flesh of the fruit during the EDB exposure.     

Compositional changes in 'Bartlett' pear ( Pyrus communis L.) cell wall polysaccharides as affected by sunlight conditions

Preharvest conditions can have a great impact on fruit quality attributes and postharvest responses. Firmness is an important quality attribute in pear, and excessive softening increases susceptibility to bruising and decay, thus limiting fruit postharvest life. Textural characteristics of fruits are determined at least in part by cell wall structure and disassembly. Few studies have analyzed the influence of fruit preharvest environment in softening, cell wall composition, and degradation. In the current work 'Bartlett' pears grown either facing the sun (S) or in the shade (H) were harvested and stored for 13 days at 20 °C. An evaluation of fruit soluble solids, acidity, color, starch degradation, firmness, cell wall yield, pectin and matrix glycan solubilization, depolymerization, and monosaccharide composition was carried out. Sun-exposed pears showed more advanced color development and similar levels of starch degradation, sugars, and acids than shaded fruit. Sunlight-grown pears were at harvest firmer than shade-grown pears. Both fruit groups softened during storage at 20 °C, but even after ripening, sun-exposed pears remained firmer. Sunlight exposure did not have a great impact on pectin molecular weight. Instead, at harvest a higher proportion of water-solubilized uronic acids and alkali-solubilized neutral sugars and a larger mean molecular size of tightly bound glycans was found in sun-exposed pears. During ripening cell wall catabolism took place in both sun- and shade-grown pears, but pectin solubilization was clearly delayed in sun-exposed fruit. This was associated with decreased removal of RG I-arabinan side chains rather than with reduced depolymerization.     

Ultraviolet C irradiation at 0.5 kJ.m(-)(2) reduces decay without causing damage or affecting postharvest quality of star ruby grapefruit (C. paradisi Macf.)

Star Ruby grapefruit [Citrus paradisi (Macf.)] were harvested in November, February, and May, treated with ultraviolet C (UV-C) light at 0.5, 1.5, or 3.0 kJ.m(-)(2), and then stored at 7 degrees C and 90-95% relative humidity (RH) for 4 weeks with 1 additional week at 20 degrees C and approximately 80% RH. Untreated fruits were used as control. UV-C irradiation at 0.5 kJ.m(-)(2) effectively reduced decay development as compared to nontreated fruit without causing damage. Irradiation at dosages >0.5 kJ.m(-)(2) did not further improve decay control and caused rind browning and necrotic peel, the extent of damage depending on treatment dosage and harvest date. The percentage of damaged fruit after irradiation at the higher UV-C dosages was significantly higher in fruit harvested in November; differences between fruits harvested in February and May were negligible. After UV-C irradiation, the phytoalexins scoparone and scopoletin accumulated in flavedo tissue, their amounts depending on harvest date and UV-C dosage. Both phytoalexins showed similar accumulation patterns, although the concentrations of scoparone were much lower than those of scopoletin. Phytoalexin levels increased in most samples as the treatment dosage increased. No detectable levels of scoparone and scopoletin could be found in nonirradiated fruit. The influence of UV-C treatments on soluble solids concentration and titratable acidity of juice was negligible.     

噻嗪酮在茶园环境中的残留行为研究

参照《农药残留试验准则》,采用田间试验方法,研究在不同地域、不同气候带、不同施药季节条件下杀虫剂噻嗪酮在南京、南宁地区茶园环境中的残留行为,并进行环境影响因素（降水、温度）分析,药剂的作物适用性及区域适用性分析,探讨了不同种植地域MRL值制定的依据。结果表明,噻嗪酮在不同环境条件下的残留行为不同。同季节施药后在两地茶叶上的消解规律相近,统计分析表明两地区的残留消解行为无显著性差异,半衰期为3.97～4.69 d;不同施药季节的降水及气温均可显著影响噻嗪酮在茶叶上的残留状态,降水可明显减少其残留量,而低温则可延长其残留半衰期;在土壤中的残留消解受土壤性质的影响较大,在南京、南宁地区的半衰期相近,但消解过程差异显著,半衰期为10.34～29.96 d。除2008年南京地区外,其他地区与年份不同处理剂量的噻嗪酮药后7 d在茶叶上的残留量均小于10 mg.kg-1,据此并参考国内外噻嗪酮MRL值的制定情况,建议延用国标（GB/T8321.6—2000）的MRL值10 mg.kg-1,建议噻嗪酮在茶叶上使用的安全间隔期为7 d。     

LC/DAD/ESI/MS method for the determination of imidacloprid, thiacloprid, and spinosad in olives and olive oil after field treatment

The behavior in the field and the transfer from olives to olive oil during the technological process of imidacloprid, thiacloprid, and spinosad were studied. The extraction method used was effective in extracting the analytes of interest, and no interfering peaks were detected in the chromatogram. The residue levels found in olives after treatment were 0.14, 0.04, and 0.30 mg/kg for imidacloprid, thiacloprid, and spinosad, respectively, far below the maximum residue levels (MRLs) set for these insecticides in EU. At the preharvest interval (PHI), no residue was detected for imidacloprid and thiacloprid, while spinosad showed a residue level of 0.04 mg/kg. The study of the effect of the technological process on pesticide transfer in olive oil showed that these insecticides tend to remain in the olive cake. The LC/DAD/ESI/MS method showed good performance with adequate recoveries ranging from 80 to 119% and good method limits of quantitation (LOQs) and of determination (LODs). No matrix effect was detected.     

土壤和番茄中氯虫苯甲酰胺的残留检测与消解动态研究

研究和建立了氯虫苯甲酰胺在土壤和番茄中的液相色谱检测方法,并采用田间试验方法研究了氯虫苯甲酰胺在土壤和番茄中的残留消解动态规律。结果表明,采用甲醇溶液浸泡提取,减压浓缩后用二氯甲烷萃取,浓缩后用二氯甲烷定容,液相色谱仪带二极管阵列检测器（DAD）测定,外标法定量。在0.05～0.5mg·kg-1添加水平范围内,土壤和番茄中氯虫苯甲酰胺的添加平均回收率为91.43%～100.91%,变异系数为3.53%～9.71%;土壤和番茄中氯虫苯甲酰胺的最小检出量均为1.0×10-7g,最低检出质量分数为0.005mg·kg-1。田间残留试验表明,氯虫苯甲酰胺在土壤和番茄中残留消解动态规律符合方程Ct=C0e-kt;150g·L-1高效氯氟氰菊酯·氯虫苯甲酰胺微囊悬浮-悬浮剂在土壤和番茄中的消解半衰期分别为6.55～11.49d和3.82～10.70d。最终残留试验研究表明,在番茄上手动喷雾施药150g·L-1高效氯氟氰菊酯·氯虫苯甲酰胺微囊悬浮-悬浮剂,按推荐剂量和1.5倍推荐剂量施药,兑水喷雾处理2～3次,施药间隔为7d,最后一次施药距采收间隔7d时,氯虫苯甲酰胺在番茄中最高残留量均小于0.3mg·kg-1。参照欧盟等规定的氯虫苯甲酰胺在番茄中最大残留限量标准,按照推荐剂量和1.5倍推荐剂量施药2～3次,距最后一次施药7d时,氯虫苯甲酰胺在番茄上残留是安全的。     

Analysis of morphological,pomological and yield characteristics of some apricot germplasm in Turkey

The purpose of this study was to characterize the Irano-Caucasian apricot germplasm that was collected in Anatolia, Turkey. Fifteen (pomological, phenological, and yield) parameters were studied in this germplasm, consisting of 128 apricot cultivars and types. A wide variation was found in harvest season, fruit yield, total solids soluble (TSS), total acidity, fruit, pit, and kernel mass. Most of the cultivars and types had a relatively small fruit size; only seven had a fruit mass ≥50 g. In general, fruits had yellow skin ground color and flesh color as well as mostly sweet kernels and high TSS. While there was a high correlation between fruit, pit and kernel mass and also between TSS and total acidity, a low or no significant correlation was determined between other pomological or phenological characteristics. The Levent apricot type possessed a substantially late ripening with a total period of 190–200 days for fruit development, a characteristic that makes this apricot type highly suitable for breeding studies.     

Effect of Calcium Foliar Application on the Characteristics of Blueberry Fruit during Storage

ABSTRACT

Effect of calcium (Ca) foliar application on blueberry fruit characteristics during storage was investigated. Calcium applications began 28 d after flowering, two levels (3.9 g Ca^{2 +} and 39 g Ca^{2 +}) and a control without calcium were used (0.0; 3.0, and 30 mL L^?1). The fruits were harvested on day 103 and were stored for 56 d at 2 ± 1°C. At harvest time the fruits had a significant statistical different concentration, which were maintained until the last day of storage. The fruit from the 30 mL L^?1 treatment was the highest. The lowest texture levels are found with the treatment without calcium, which shows a statistically significant change from storage day 29. The LMP percentage did not varied in the fruit from the treatment with 30 mL L^?1, but did in the fruit without calcium. Hunter L, b, and the index chromes were influenced by the applied calcium levels, significantly greater at 30 mL L^?1; and by the time of storage in the fruits with treatment of 30 mL L^?1.     

Resveratrol treatment controls microbial flora, prolongs shelf life, and preserves nutritional quality of fruit

Resveratrol is known as a grapevine secondary metabolite with fungicide activity. Its exogenous application on harvested grapes resulted in the reduction of microbial flora growth, and consequently, prolonged shelf life, without affecting the nutritional quality of the fruit. Resveratrol treatment also resulted in being effective on fruit that normally does not accumulate such metabolites as, for example, tomatoes, apples, avocado pears, and peppers. As a result, all treated fruits maintained their post-harvest quality and health longer than the untreated ones. This study demonstrates the potential use of resveratrol as a natural pesticide to reduce post-harvest fungi development on a broad spectrum of fruit types.     

Residues of vinclozolin and procymidone after treatment of greenhouse grown lettuce,tomato and cucumber

Residues of the fungicides vinclozolin and procymidone, used to control the Botrytis cinerea disease, were studied in greenhouse grown lettuce, tomato and cucumber. Residue concentrations differed between the species of treated vegetables, and depended mostly on time of picking (harvest), size of fruits and mode of chemical application. The differences in concentration between one and two applications became smaller with time after application. The greatest differences occurred in lettuce. The residue contents in cucumber fruits assigned both for industrial and home processing (pickling) were higher than the legal limit (3 mg/kg). As a result of washing cucumbers, 22–24% of the residue was eliminated, and by peeling them 79–85% of the vinclozolin and procymidone residues were eliminated. Therefore it is reasonable that one or two applications of these fungicides should be used, with a time lapse of 14 days, but only with cucumbers intended for salad consumption. Vinclozolin residues, when used as vaporisation tablets, were in all cases 35–65% lower compared with the wettable powder (WP) formulation; however, the rate of of residue decrease was much slower. When applied in the form of vaporable tablets, the vinclozolin residue concentration was lower in all the sampled fruits in comparison with the WP formulation. The concentration of fungicide residues detected in winter tomato fruits was higher than that of the spring crop. Irrespective of vegetable the detected levels of fungicide residues were lower in ripe and bigger fruits than in green and smaller ones.