氮素形态对菠菜硝酸盐及草酸含量的影响

 采用水培试验, 研究了不同铵硝配比对菠菜体内硝酸盐和各形态草酸含量及分布的影响。结果表明, 生物量随供铵比例的增加先显著升高, 后显著下降, 在铵硝比为25 /75和50 /50时具有最高生物量。各器官的硝酸盐含量随着供铵比例的升高而显著下降, 叶片的草酸总量和可溶态草酸随营养液中铵态氮比例的升高显著降低, 而叶柄和侧根的草酸含量在铵硝比为50 /50时最低, 主根的草酸含量也随铵态氮比例的增加而下降。草酸在菠菜各器官的含量为叶片>主根>叶柄>侧根, 并且叶片含量要远远高于其它器官。菠菜体内的草酸以可溶态为主, 除在单独供铵处理的叶片中仅占总草酸含量的38%以外, 其它处理的均占草酸总量的69%以上。可见, 调节营养液中铵硝比例可以调控菠菜体内各形态的草酸含量。铵硝比为25 /75和50 /50时不仅有利于菠菜生长, 而且可降低菠菜体内的可溶态草酸和草酸总量。     

不同氮形态配比对菠菜硝酸盐、草酸含量的影响

通过水培试验研究了不同氮形态对菠菜硝酸盐、草酸含量的影响.结果表明:在NO3-N/NH4 比例为100/0时菠菜的生物量最大,而随着NH4 比例的增加,菠菜的生物量呈递减趋势,根冠比则在升高.菠菜可食部位的硝酸盐、草酸含量随铵态氮比例的增加逐渐减少,在完全供铵时含量最少.NO3-N/NH4 比为25/75时Vc含量最高.     

Nutritional quality of greenhouse lettuce at harvest and after storage in relation to N application and cultivation season

The effect of five levels of nitrogen fertilization on the growth and nutritional quality of Cos lettuce (Lactuca sativa L. cv. Parris Island) at harvest and after storage was studied during autumn and winter in South-West Greece. Plants were cultivated hydroponically in a greenhouse and the nitrate, chlorophyll and ascorbic acid (vitamin C) concentrations within the plant tissues were measured at harvest and following storage at 5 or 10 °C for 10 days. Nitrate accumulated in the leaves with increasing amounts of N within the nutrient solution and was higher in the winter than in the autumn. At the lowest N level (20 mg L⁻¹), the inner leaves accumulated more nitrate than the outer leaves, whereas at higher N levels (140, 200 or 260 mg L⁻¹) nitrate accumulation was higher in the outer leaves. Overall, the highest nitrate concentrations were detected in the petiole and the proximal end of the leaf, but at the lowest N application rate (20 mg L⁻¹) nitrate accumulated in the distal region of the leaf too. Although the nitrate concentrations within the leaves did not change significantly during 10 days storage at 5 or 10 °C, the chlorophyll and vitamin C concentrations decreased. Chlorophyll loss was higher in lettuce that was grown under low N levels and was higher at 10 °C than at 5 °C, but was reduced by enclosure of the lettuce in polyethylene film. It is concluded that the optimum N application rate for Cos lettuce grown hydroponically under cover during autumn and winter in South-West Greece, and in other areas with a similar climate, is 200 mg N L⁻¹ because at this N rate yield is satisfactory and leaf nitrate concentrations are below the maximum acceptable level for human consumption. Nutritional value (vitamin C concentration) and market quality (chlorophyll content) are highest at harvest and decrease during storage, but quality in terms of nitrate concentration does not change.     

不同来源菠菜品种营养品质分析与评价

为评价不同来源菠菜品种的营养品质,筛选出营养物质含量丰富,硝酸盐、单宁和草酸含量低的品种,测定了34份 菠菜材料的水分、VC、可溶性糖、粗纤维、草酸、单宁和硝酸盐7个品质指标的含量,并用模糊数学的隶属函数法对其营养品 质进行了综合分析。结果表明：不同菠菜品种在品质方面有较大的差异,34份菠菜材料中,用隶属函数法分析综合营养品质 最好的是欧洲的胜先锋、日本的トライ和アソナ,但在所有品种中,国内的京菠1号VC含量最高,达601.0 mg·kg^-1(FW),且 硝酸盐含量最低。     

Effects of N fertilizers and rates on yield,safety and nutrients in processing spinach genotypes

Two field experiments were carried out at the Experimental Field, Department of Food Science (TE, Italy) in 2004 and 2005 to evaluate the effects of genotypes, different N forms and N rates on yield, safety and nutritional features of processing spinach. Experiment 1, as treatments, included spinach genotypes and N forms (CO(NH₂)₂; Agricote; NH₄NO₃); experiment 2 included three N forms (Ca(NO₃)₂; (NH₄)₂SO₄; NH₄NO₃) applied at rates of 0, 75, 150, 200 kg N ha⁻¹. This research work confirmed differences among spinach genotypes in terms of efficiency in N use and oxalate and nitrate accumulation. Spinach accumulated much more nitrate in petioles and much more oxalate in blades indicating that nitrate and oxalate might play a counterrole to each other. Fertilizers containing N under forms not readily available to the crop, i.e. Agricote, CO(NH₂)₂ and (NH₄)₂SO₄, increased nitrate and oxalate accumulations less than fast N-release fertilizers, but their effect on yield was limited. Highest yield with contents of nitrate and oxalate lower than the limits imposed to avoid health problems, were achieved with Ca(NO₃)₂, at rates of 130 and 150 kg N ha⁻¹ NH₄NO₃.     

天然沸石作为缓释肥材料在菠菜种植上的应用研究

采用盆栽试验研究了天然沸石作为缓释肥材料对菠菜生物量及相关品质的影响。结果表明：沸石粉吸附1/2氮钾肥（Z+1/2NK）处理的氮钾肥用量为常规施肥（CF）的一半,而生物量却增加了22.31 %;本试验条件下,常规施肥CF和Z+1/2NK处理的菠菜VC含量最高;常规施肥CF和施用沸石各处理的菠菜硝酸盐含量均比对照显著增加,其中Z+1/2NK处理的菠菜硝酸盐含量最高,为1 671 mg·kg^-1,但远远低于我国规定的硝酸盐安全限值（3 100 mg·kg^-1）,可以放心食用;Z+1/2NK处理的菠菜草酸总量、可溶态草酸和难溶态草酸含量较其他施用沸石处理均显著降低,同时降低了可溶态草酸占草酸总量的比例,增加了难溶态草酸占草酸总量的比例,从而在一定程度上降低了草酸对人体健康的危害。总之,在本试验条件下Z+1/2NK处理最适合菠菜生产。     

Effects of conventional and organic fertilization on spinach (Spinacea oleracea L.) growth,yield, vitamin C and nitrate concentration during two successive seasons

Current experiment was laid out in order to compare different kinds of organic manure and chemical fertilizer application in growing spinach under the open-field conditions in two successive seasons. Matador type spinach (Spinacea oleracea L.) was cultivated organically and conventionally and spinach growth, yield, vitamin C and nitrate concentrations were checked throughout two successive seasons (autumn and winter). Commercial chemical fertilizer was used as conventional application, and chicken manure (CM), farmyard manure (FM) and blood meal (BM) were used as organic manure applications as a single and as mixtures at different quantities by aiming to receive 150 kg N ha⁻¹ for each, totally 19 applications. In general, autumn season gave the better results in terms of spinach growth, yield and resulted in lower nitrate concentration, whereas the vitamin C concentration was found to be higher in winter season. Reasonable applications to be recommended should be as follows with regard to the seasons; 3.5 ton ha⁻¹ CM and 0.6 ton ha⁻¹ BM + 0.85 ton ha⁻¹ CM + 4.0 ton ha⁻¹ FM for spinach growth; 3.5 ton ha⁻¹ CM and 5.0 FM + 1.2 CM + 0.4 BM applications for spinach yield; 5.0 ton ha⁻¹ FM + 2.5 ton ha⁻¹ CM and 15.0 ton ha⁻¹ FM for vitamin C and nitrate concentration in the autumn and the winter season, respectively. In conclusion, FM and CM can be used effectively in growing organic spinach especially in the autumn season and can be transferred successfully into an asset.     

Postharvest physiology of Corchorus olitorius baby leaf growing with different nutrient solutions

The storage at 4°C in darkness of Corchorus olitorius L. baby leaf as a ready-to-eat (RTE) vegetable has been studied for the first time. C. olitorius was cultivated in a floating system with different nutrient solutions: standard (NS100%) or halved (NS50%). Several quality factors of this produce were evaluated during season (spring, summer, autumn) considering treatments and days of storage in order to understand the interactions. During storage, sucrose, total and reducing sugars, nitrate, phenolic compounds, anthocyanins, chlorophylls, and carotenoids were measured. Results showed that chlorophylls decreased by 20–30% for both treatments and the changes were statistically different during spring. Carotenoid content did not change until the end of the storage and values ranged from 0.60 g kg^?1 to 0.75 g kg^?1 fresh weight depending on the season. Phenols and anthocyanins decreased within 10 days: ?40% of phenols and ?50% of anthocyanins, respectively. No interaction between nutrient solutions and storage behaviour was reported. Thus, C. olitorius resulted to be a good source of nutraceutical compounds and it is able to maintain these components during storage. Moreover, the public interest in regards to nutritional and healthy food is rapidly increasing, promoting the discovery of new vegetables, like C. olitorius, for RTE commercialisation.     

宫内伊予柑果实发育期间色泽和色素的变化

 以宫内伊予柑为试材, 对果实发育期间色泽、色素种类及含量, 尤其是类胡萝卜素组分进行了研究。结果表明, 幼果中高含量的叶绿素使果实呈现青绿色, 采前8周起类胡萝卜素开始积累, 采前4周起随叶绿素含量下降黄色得以显现。果实类胡萝卜素主要存在于果皮中, 成熟果实果皮类胡萝卜素含量达囊瓣的16.62倍, 总量占整果的83.62%。用高效液相色谱—二极管阵列检测(HPLC - PDAD) 技术,对采前12周至采收期的果皮类胡萝卜素组成进行了分析, 共分离出类胡萝卜素组分23种, 其中7种得到鉴定。在采收期果皮中, 已鉴定的类胡萝卜素中以β - 隐黄质和玉米黄素较丰富, 占总类胡萝卜素的8.00%和6.78%; β - 胡萝卜素不足总类胡萝卜素的1% , 没有检测出α - 胡萝卜素和番茄红素。果实成熟过程中β - 隐黄质及玉米黄素含量上升, 并伴随α - 胡萝卜素、叶黄质和β - 胡萝卜素含量下降, 暗示类胡萝卜素的β主链合成能力和β环羟化活性急剧增强, 与此同时, 阿朴类胡萝卜素的出现则表明类胡萝卜素的裂解能力随果实成熟而上升。     

Quality changes in hydroponic lettuce grown under pre-harvest short-duration continuous light of different intensities

Summary

The effect of pre-harvest light intensity on the quality of hydroponically-grown lettuce (Lactuca sativa var. capitata L.) was studied by growing lettuce under 48 h of continuous illumination delivered by red- or blue-light-emitting diodes (LEDs) with a red:blue ratio of 4.0. Four light intensity treatments (50, 100, 150, or 200 µmol m^–2 s^–1) were applied. The results showed that the nitrate concentrations in lettuce shoots decreased significantly after treatment with 48 h of continuous light, while the contents of soluble sugars and vitamin C increased substantially. It was observed that the effect of pre-harvest short-duration continuous light (PSCL) on improving lettuce quality was significantly influenced by the intensity of the light. The decrease in nitrate concentration and the increases in soluble sugars and vitamin C contents were relatively low at a light intensity of 50 µmol m^–2 s^–1, but increased gradually as the light intensity increased from 50 µmol m^–2 s^–1 to 200 µmol m^–2 s^–1. However, the marginal benefit of increased light intensity in lowering nitrate concentration and increaseing vitamin C content declined rapidly when the light intensity increased beyond 100 µmol m^–2 s^–1. In conclusion, PSCL offers an effective method by which to improve the quality of lettuce, and a light intensity of between 100 µmol m^–2 s^–1 – 150 µmol m^–2 s^–1 is the economic optimum.     

菠菜有机生态型基质栽培施肥技术研究

利用农业有机废弃物作为无土栽培基质，以菠菜（Spinacia oleracea L.)为试验对象进行盆栽试验。结果表明，在菠菜无土栽培中，有机无机固体肥配合施用可以显著提高菠菜的品质和产量，其可食部位的维生素C含量明显高于其他肥料处理，而对人体有害的硝酸盐含量则显著低于其他肥料处理。     

金桂及其芽变花色表型及色素成分分析

以金桂及其芽变花为试验材料,利用英国皇家园艺学会比色卡(Royal Horticultural Society Color Chart,R.H.S.C.C.)和色差仪测量两种花的颜色表型,通过显色法和紫外—分光光度计初步确定了两种花的主要色素类型,并且利用高效液相色谱—光电二极管阵列(HPLC–DAD)测定花瓣中类胡萝卜素和总黄酮含量,利用高效液相色谱—大气压化学电离源—质谱联用技术(HPLC–APCI–MS)和标准品鉴定主要类胡萝卜素成分。结果发现,芽变枝条上的花色由母本的黄色(R.H.S.C.C.12B~13A)变为橙红色,且花瓣边缘和内部颜色不同(内侧R.H.S.C.C.23B,花瓣外缘R.H.S.C.C.N25A);两种花瓣中均含黄酮类化合物,不含花青素苷,且两者的类胡萝卜素含量存在一定差异;从两种花瓣中分离鉴定出主要的类胡萝卜素成分为α–胡萝卜素和β–胡萝卜素,这两种组分和类胡萝卜素总量在芽变花瓣中极显著高于母本,而两种花瓣的总黄酮含量无显著性差异。因此,最终可以确定引起芽变花色变化的主要色素成分为类胡萝卜素。     

Flowering and fruiting phenology,and physico-chemical characteristics of 2-year-old plants of six species of Opuntia from eight regions of Morocco

SUMMARY

We have described the flowering and fruiting phenology of 14 accessions of six Opuntia species grown in Morocco: O. ficus-indica, O. robusta, O. aequatorialis, O. dillenii, O. leucotricha, and O. stricta. We also determined the physicochemical characteristics of their cladodes. For each accession, we used four-to-20 plants. Two systems were used to measure phenology: the extended Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH)-scale and the National Phenology Monitoring System. Five principal stages were described: the development of vegetatively-propagated organs (vegetative buds), the development of flower buds, flowering, fruit development, and fruit maturity. The number of vegetative buds varied significantly among the 14 accessions, while only four accessions produced flower buds. After reaching their final size, fruit lengths varied from 3.40–6.40 cm, while fruit diameters varied from 1.93–3.90 cm. The average cladode number differed significantly among genotypes and varied from 1.75–7.75. There were also significant differences in cladode length (13.75–30.63 cm), width (6.25–17.33 cm), thickness (0.65–1.38 cm), fresh weight (FW; 67.50–766.00 g), and dry weight (DW; 8.75–67.15 g) between species. Water content and ash content, as well as total protein and total sugar concentrations, showed significant differences and were within the ranges of 86.67–92.04% (w/w), 12.97–22.08g 100 g^?1 DW, 4.64–11.56g 100 g^?1 DW, and 3.22–12.51 g 100 g^?1 DW, respectively. Our results will help in the development of agronomic management practices and improve the characterisation, valorisation, and use of cactus pear species grown in Morocco.     

紫叶生菜和绿叶生菜品质的综合比较

为评价紫叶生菜和绿叶生菜的营养价值,选取紫叶生菜和绿叶生菜品种各4个,分别测定、比较了其可溶性糖、可溶性蛋白、维生素C、硝酸盐和花青素含量。试验结果表明,绿叶生菜(GT)品种可溶性糖含量整体均高于紫叶(VT)品种,平均高112.9%;整体上VT与GT的硝酸盐含量差异不大,其中VT中深紫色的VT_1硝酸盐含量显著高于其他品种,GT中深绿色的GT₁硝酸盐含量高于其他品种;所有VT品种的可溶性蛋白、维生素C以及花青素含量均高于GT品种,其中VT品种的可溶性蛋白和维生素C含量分别比GT的高80.6%、33.4%。另外,只有紫叶生菜含有花青素,其中深紫色的VT₁花青素含量最高,随叶色变浅而逐渐降低。以上结果说明绿叶生菜品种可溶性糖含量显著高于紫叶品种,且较紫叶生菜口感好,但紫叶生菜的可溶性蛋白、维生素C以及花青素含量高于绿叶生菜。     

The carotenoid pigments of the date

The carotenoid pigments of the date (Phoenix dactylifera) were investigated in 2 soft cultivars, ‘Hayany’ and ‘Barhee’, and in the semi-dry ‘Deglet Noor’. The total carotenoid content in the ripe fruit was 10–12 μg/g fresh weight. The carotenoid pattern in all investigated fruits was that of the chloroplast type, with only slight differences between the cultivars. Changes in the carotenoid pattern during ripening were followed in ‘Hayany’ and ‘Deglet Noor’. The total carotenoid content decreased drastically from 36.3 to 21.2 μg/g dry weight in the soft dates, and from 23.2 to 12.0 μg/g dry weight in the semi-dry cultivar. The carotenoid degradation may be due primarily to the loss of moisture during maturation, and is probably unrelated to the gradual darkening of the ripening fruit. The pattern of the retained carotenoids remained essentially similar.The vitamin A values of the 3 cultivars, expressed as retinol equivalents, were calculated.     

Yield and quality of Corchorus olitorius baby leaf grown in a floating system

Corchorus olitorius is mainly cultivated in Africa and is used in the human diet for its nutraceutical proprieties. In this work, C. olitorius was grown in a floating system using a standard (NS100%) or halved (NS50%) nutrient solution. Yield was evaluated at harvest when plants reached the baby leaf stage. Quality of leaves was estimated by measuring sugars, nitrate, chlorophylls, carotenoids, polyphenols, and anthocyanins. Yield was similar to other common leafy vegetables cultivated in floating systems. Analytical determinations showed good levels of antioxidant compounds and sugars. Mineral contents were relevant for Ca, Mg and Fe in comparison with C. olitorius cultivated in soil and other common leafy vegetables. Results showed these plants had healthy characteristics for human nutrition, in particular for women and children. C. olitorius had a good performance in the floating system with yield ranging from 0.8 to 2.4 kg m^?2. Mineral nutrient levels were higher than in the major leafy vegetables. Nutrient solutions influenced anthocyanin accumulation (+37% in NS50% in spring and +48% in NS50% in summer). Leaf nitrate content was –50% in NS50% at spring cultivation. The overall quality parameters suggest that C. olitorius can be an optimal candidate for baby leaf production in the fresh cut leafy vegetable industry.     

‘中油桃9号’及其黄肉芽变的类胡萝卜素代谢和基因表达分析

以‘中油桃9号’（白肉）及其黄肉芽变的果肉为试材,采用HPLC法对类胡萝卜素的积累水平进行定性和定量分析,实时荧光定量PCR法对类胡萝卜素代谢关键基因的表达水平进行分析。结果表明：在幼果期,‘中油桃9号’与突变体的果肉颜色无明显差异,但在果实成熟时差别很大;幼果期时‘中油桃9号’与突变体的类胡萝卜素总量相近,以β–胡萝卜素、紫黄质和叶黄质为主;果实成熟期‘中油桃9号’的类胡萝卜素总量比突变体高很多,呈现出高含量的紫黄质、β–胡萝卜素和玉米黄质;实时定量表达分析表明,果实成熟期‘中油桃9号’的CCD4转录水平比突变体高得多。果实成熟时CCD4基因的表达差异可能是导致‘中油桃9号’与突变体类胡萝卜素积累差异的主要原因。     

芥蓝种质资源营养成分及商品性评价

对13份芥蓝种质资源的部分营养成分进行测定及评价,并进行相关性分析。结果表明:VC含量变化范围为0.80～1.41 mg·g^-1（FW）;类胡萝卜素最高含量为0.016 6 mg·g^-1（FW）;还原糖含量变化范围为2.85～8.17 mg·g^-1（DW）;可溶性糖含量变化范围为12.38～23.80 mg·g^-1（DW）;13份芥蓝的蛋白质含量较低,粗纤维含量中等,材料间差异不大。商品性评价结果表明：风味最好的是Ba17,质地最好的是Ba35,外观最好的是Ba25和Ba44。相关性分析表明：还原糖含量与可溶性糖含量呈极显著正相关,与甜味呈显著正相关,与蛋白质含量、类胡萝卜素含量、鲜味呈显著负相关;蛋白质含量与可溶性糖含量呈极显著负相关;鲜味与甜味、VC含量与可溶性糖含量呈显著负相关;脆度与纤维感呈显著正相关,且与其他性状没有显著相关关系;粗纤维含量与纤维感、脆度没有相关性。     

Antioxidant Capacity,Phenolic Compounds and Antioxidant Enzymes of Wild Grape Seeds from Different Accessions Grown in Iran

Grape seeds contain high levels of phytochemicals, that have been associated with a reduced risk of chronic diseases. In this study, the polyphenolic content, antioxidant capacity and antioxidant enzymes activity in the seeds of 20 wild grape accessions native to Iran were investigated. The antioxidant capacity of the wild grape seeds was evaluated by DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating. Total phenolic (TP), total flavanoid (TF) and total proanthocyanidin (TPA) content ranged from 44.86 to 155.1, 23.21 to 131.91, and 10.11 to 26.10?mg/g seed, respectively. All seed extracts showed remarkable DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating ranging from 27.34 to 78.57%, 198.83 to 590.86?µmol TE/g and 23.12 to 62.98%, respectively. Grape seed extracts had the greatest antioxidant enzymes activity guaiacol peroxidase (G-POD), superoxide dismutase (SOD), and catalase (CAT). Based on HPLC analyses, catechin was the most abundant compound identified (25.89?mg/g) for all accessions. Additionally, significant correlations among different antioxidant assays were found. With the high amount of total phenolic content, antioxidant capacity and antioxidant enzymes activity, seeds of P6, P7 and P8 accessions might be evaluated as a nutritional supplement.     

‘中油桃9号’及其黄肉突变体花和叶片中类胡萝卜素代谢及相关基因的时空表达

以‘中油桃9号’及其黄肉芽变的花和叶片为试材,采用HPLC法对类胡萝卜素的积累水平进行定性和定量分析,实时荧光定量PCR法对类胡萝卜素代谢关键基因的表达水平进行分析。结果表明:在花萼中,黄肉突变体的总类胡萝卜素水平为‘中油桃9号’的5.7倍,其中的β–胡萝卜素为‘中油桃9号’的19.6倍;除DXS和LCY-E外,突变体花萼中无论是合成类胡萝卜素的基因,还是降解类胡萝卜素基因的表达水平均显著高于‘中油桃9号’。在花瓣中,两个材料的类胡萝卜素总量无显著差异,但各类胡萝卜素成分含量存在显著差异;突变体DXS、HDR、PDS、LCY-E、CHY-B和CCD1的表达量显著高于‘中油桃9号’,ZDS、NCED1和CCD4的表达量显著低于‘中油桃9号’。在叶片中,‘中油桃9号’和黄肉突变体均以β–胡萝卜素、紫黄质、9–顺式–紫黄质和叶黄质为主,幼果期时两个材料的类胡萝卜素总量无显著差异,果实成熟后突变体的类胡萝卜素总量呈上升趋势,显著高于‘中油桃9号’;自花后55～80 d,仅CCD4的表达模式与类胡萝卜素的积累一致,因而认为CCD4的表达差异是两个材料后期叶片类胡萝卜素含量差异的主要原因。