不同移栽期对烤烟生长发育及质量风格的影响

通过田间试验和化学分析等方法,对福建翠碧1号进行了试验研究。结果表明,随移栽期的推迟,烟株生长速度加快,烟株株型明显增大,烤烟伸根期明显缩短;推迟移栽期至2月15日,烤后烟叶产量、产值显著上升;但推迟到3月份移栽出现下降,对上等烟比例和均价影响不显著。随移栽期的推迟,烤后烟叶相同等级的烟碱和总氮呈下降的趋势,还原糖/烟碱比值和总氮/烟碱比值呈上升的趋势,对烤后烟叶总糖、还原糖、钾含量和两糖比的影响没有规律性变化。随移栽期推迟,烟叶风格特征由清香转变为浓香,评吸质量变差。适当早栽可以显著改善烟叶评吸品质,但应改进栽培技术保证烟叶的产量和产值。     

移栽期对烤烟成熟期间几个生理生化指标和经济性状的影响

为探讨移栽期对烟叶品质形成的影响,采用田间试验方法,研究了不同移栽期下烤烟成熟期的质体色素含量、碳氮代谢关键酶活性的变化。结果表明,移栽期显著影响烤烟品质和产量的形成。提前移栽烟叶成熟前期质体色素含量、硝酸还原酶(NR)活性和淀粉酶活性提高,NR活性峰值出现的时间较晚,有利于延长烟叶的功能期,但过度提前移栽的烟叶成熟后期叶绿素含量和硝酸还原酶活性较高,碳氮代谢转化不协调,不利于烟叶的成熟落黄,烤后烟叶产量和产值均较低,推迟移栽有利于提高烤后烟叶产量,但酶活性和质体色素含量较低,导致烟叶早衰,降低烤后烟叶产值、中上等烟比例和均价。不同移栽期试验表明,粤北烟区的适宜移栽期为2月19日-2月24日。      

烤烟品种G-80的最佳播栽期探讨

播栽期的适宜与否,对不同品种烟株的生长发育、烟叶成熟与产质量的关系相当密切.我省烤烟优质适产栽培技术规范的播种期在"寒露"后"立冬"前播完,移栽期闽西烟区在"冬至"至"大寒".G-80品种如按这一播栽期进行,此品种因对低温特别敏感常导致不同程度的早花,品种的优良性状没得到充分发挥,在大田表现烟株矮小老化、叶片窄长、叶数减少、腋芽丛生.其结果是产量、质量、产值均不甚理想.为探讨G-80品种的最佳播栽期,现将有关试验与调查结果分析如下:     

不同移栽期对秦烟96产量和品质的影响

为了确定烤烟最佳移栽时间,以秦烟96为供试材料,采用田间小区试验调查了移栽期对烤烟产量和品质的影响。结果表明,移栽期向后推迟,烤烟产量、均价、产值和中上等烟比例均表现出先升高后降低的趋势。移栽期改变对烤烟化学成分影响显著,且不同叶位存在一定差异。与对照相比,化学成分适宜程度因叶位而不同,移栽期延后,4个叶位,烟叶化学品质均先升高后降低;同时,腰叶、下二棚叶化学品质优于顶叶、上二棚叶。秦烟96在洛南烟区的适宜移栽时间为5月10日,适宜的移栽期有利于烤烟生长发育,进而提高烟叶产量和品质。     

施钼对烟草叶绿素含量、光合速率、产量及品质的影响

在大田条件下,对K326、云烟85、CB-1、红花大金元4个烟草品种进行叶面喷施钼肥,研究施钼对烟草叶片叶绿素含量、光合速率、产量和品质的影响.结果表明,施钼能提高4个品种烟草生育前期叶片叶绿素的含量和光合速率,提高烤后烟叶中上等烟的比例,显著降低杂色烟的比例,增加烟叶产量和产值,提高烟叶含钾量和含钼量.     

闽西烟区红花大金元适宜移栽期研究

为明确清香型烤烟品种红花大金元在闽西烟区的适宜移栽时期,采用田间小区试验方法,研究了移栽期对烤烟生长、产量和品质的影响。结果表明,1月12日移栽,大田生育期149 d,能满足大田生长的需要,地上部鲜重、干重最大,单叶重、产量、产值、均价和上中等烟比例均明显优于其他处理,烟叶主要化学成分较为协调;在烟叶感官评吸质量方面,适当提早移栽有利于清香风格特色的彰显,甜感更强,香气量更足,香气质更好。     

不同苗龄移栽对烤烟生长发育及其产值和品质的影响

本试验主要研究不同移栽苗龄对烤烟植物学性状、产值和内在品质的影响。研究表明,移栽苗龄以四叶一心为佳,随移栽苗龄的增大,烟株的生育期缩短,烟株抗病能力降低,烟株的生长发育速度加快,株高、节距和叶面积日平均增长量显著升高。同时随移栽苗龄的增大,烤后烟叶质量变差,烟叶还原糖和烟碱含量降低,亩产量、产值和上中等烟比例降低,经济效益明显下降。     

不同移栽期对陕南烤烟氮钾含量、光合特性及经济性状的影响

为了探明陕南烟区主栽品种K326的适宜移栽期,在陕南旬阳县开展了烤烟移栽期试验研究。结果表明,随移栽期推后,各主要生育期均向后推迟,大田生育期缩短;旺长期、平顶期和成熟期烟叶氮钾、叶绿素和碳水化合物含量及净光合速率均先升高后降低,产量、均价、产值和中上等烟比率均表现出同一趋势。综合分析,依据当地气候条件特点,以旬阳试验点为代表的相同海拔区域,烤烟K326最适宜移栽期为5月10日;确定适宜移栽期可改善烟叶氮钾营养,提高光合性能,有利于干物质累积,从而提高烟叶的产量和品质。     

不同移栽期对恩施烤烟产量和质量的影响

为了明确移栽期对恩施烤烟产量和质量的影响,在湖北恩施的宣恩、利川和巴东3个县(市)开展了烤烟移栽期试验研究。结果表明,依据当年气候条件特点,以宣恩试验点为代表的相同海拔区域,移栽期较常规移栽期适当提前可以提高烟叶的产量和品质,4月29日移栽的处理烟株田间长势、烤后烟叶产量、化学成分协调性等均优于5月6日,5月13日和20日的处理,建议宣恩试验点烟苗在4月底5月初移栽;以利川试验点为代表的相同海拔区域,各处理烟叶化学成分差异显著,5月13日和20日移栽的烟株在各方面表现较好,建议在5月中旬移栽以获得优质烟叶;以巴东试验点为代表的相同海拔区域,5月9日移栽的烟株比提前或推迟移栽的经济效益高,烟叶内在化学成分协调性比较好,成熟期雨量较少,建议在5月中上旬移栽以保证当地气候资源的有效利用,提高烟叶产质量。     

不同光叶紫花苕子翻压量对烤烟产量和品质的影响

采用田间小区试验的方法探讨了施用70％化肥条件下不同光叶紫花苕子翻压量对烤烟生长发育以及烟叶产量、产值和化学成分含量的影响.结果表明,翻压适量的绿肥能够促进烟株的生长,尤其是叶片的开片;增加烟叶的SPAD值;提高烟株干物质积累量及烤后烟叶的产量,改善烟叶的化学品质.当翻压22 500 kg/hm2绿肥时,烟叶的产量、产...     

Mineral contents of some southern Italian wines. II. Determination of Li, Na, Mg, K, Ca, Co, As, Rb, Sr, Ag, Sb, Ba

Following our study of the mineral contents of some Southern Italian wines, this work reports on the detection of 12 elemental components. The elements were determined using ICP-AES, flame atomic emission or absorption spectroscopy. The values determined for Li, Na, Mg, K, Ca, Rb, Sr and Ba were within the usual ranges for wines (average values for these elements were: 0.010, 26.2; 94.4; 888; 94.0; 3.30, 0.82 and 0.11 mg/l respectively). All the wines contained low levels of As, the concentrations of which were always under 0.20 mg/l, the maximum level permitted by E.E.C. standards. The measuring of Co, Ag, and Sb led us to ascertain, in all the wines, concentrations lower than 0.01 mg/l for Co and Ag and below the instrumental detection level for Sb (0.06 mg/l). In a previous study wines from D.O.C. areas of Southern Italy were analysed by the technique of inductively coupled plasma atomic emission spectroscopy (ICP-AES), for 14 minerals. This paper deals with further investigation of the mineral composition of the same wines for different metal constituents, analysed by ICP-AES, flame atomic emission, or atomic-absorption spectroscopy (two techniques). The first technique was applied to the detection of Co, As, Sr, Ag, Sb, and Ba. The alkaline metals Li, Na, K, and Rb were determined by flame atomic emission, a technique which possesses better detection limits for these elements. For Mg and Ca the atomic absorption methods were applied.     

Isolation,Composition, Structure,Properties, Modifications,and Uses of Yam Starch

Starch is the major carbohydrate in yam tubers and can amount up to 80% of the dry matter. The starch quality determines the quality of food and industrial products made from yam tubers. This review summarizes the present knowledge of the isolation, composition, structure, property, modifications, and uses of starches from diverse yam species. Compared with other tuber and root starches, there is a lack of systematic information on the yam starches. This hinders the further development of yams as sustainable crops as well as the value‐added processing of the starches. Therefore, suggestions on how to better understand and utilize these starches are provided.     

卷烟中锂、铬、镍、铜、砷、硒、钼、镉、铊和铅含量分析

采用微波消解-电感耦合等离子体质谱法测定了41个牌号烤烟型卷烟和雪茄烟样品烟丝中的锂、铬、镍、铜、砷、硒、钼、镉、铊和铅含量,并按照类型和价位对卷烟中这10种有害元素含量进行了统计分析。结果发现:①卷烟中锂和铜的含量较高,铊的含量很低,铬、镍、镉、铅、砷、硒和钼7种元素的平均含量为0.55～4.42μg/g;②雪茄烟中铬、镍、砷、钼、镉、铊和铅的含量一般高于烤烟型卷烟,而硒元素的含量则相反,但差别较小;烤烟型卷烟中锂和铜的含量与雪茄烟没有显著差异;③高档卷烟中的锂、镍、镉、铊和铬含量较低,而砷、铅的含量较高;不同价位卷烟的铜、硒和钼含量差异不显著。     

Survey of trace elements (Al,As, Cd,Cr, Co,Hg, Mn,Ni, Pb,Se, and Si) in retail samples of flavoured and bottled waters

Concentrations of eleven trace elements (Al, As, Cd, Cr, Co, Hg, Mn, Ni, Pb, Se, and Si) were measured in 39 (natural and flavoured) water samples. Determinations were performed using graphite furnace electrothermetry for almost all elements (Al, As, Cd, Cr, Co, Mn, Ni, Pb, and Si). For Se determination hydride generation was used, and cold vapour generation for Hg. These techniques were coupled to atomic absorption spectrophotometry. The trace element content of still or sparkling natural waters changed from brand to brand. Significant differences between natural still and natural sparkling waters (p < 0.001) were only apparent for Mn. The Mann–Whitney U-test was used to search for significant differences between flavoured and natural waters. The concentration of each element was compared with the presence of flavours, preservatives, acidifying agents, fruit juice and/or sweeteners, according to the labelled composition. It was shown that flavoured waters generally increase the trace element content. The addition of preservatives and acidifying regulators had a significant influence on Mn, Co, As and Si contents (p < 0.05). Fruit juice can also be correlated to the increase of Co and As. Sweeteners did not provide any significant difference in Mn, Co, Se and Si content.     

The effect of storage of canned juices on content of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd, Sb and Ni

The increase in concentration of iron, copper, zinc, lead, antimony, aluminium, cadmium, tin and nickel over a 2 year's time of juices of peach (prunus persica), pear (pyrus communis), apricot (prunus vulgaris) and apple (malus pumila) was determined. The results show a considerable increase in Fe, Cu, Pb, Zn and Sn with time, while the change in Al, Cd, Ni and Sb is negligible.     

Analysis of cheese for histamine, tyramine, tryptamine, histidine, tyrosine, and tryptophane

A method is described for determining the content of selected biologically active amines (histamine, tyramine, tryptamine) and amino acids (histidine, tyrosine, tryptophane) in cheeses by high performance liquid chromatography. The amines and amino acids were quantified by employing a counter ion-containing mobile phase and by comparing peak areas of high performance liquid chromatography charts for sample cheeses versus standard cheeses containing known amounts of added amines based on dual injections of samples and standards. Recovery of amines and amino acids varied from 87.5 to 111%. Histamine, which has been associated with food poisoning in concentrations of 185 mg/100 g in Swiss cheese and 180 to 500 mg/100 g in fish, was found in concentrations above 500 mg/100 g in Swiss cheese. The high performance liquid chromatography analytical method should be useful for screening to detect cheese samples containing toxic amounts of histamine and for research studies designed to determine the cause and effect relationships for histamine production in cheese.     

In Vitro Digestion of Raw,Roasted, and Pressure-Flaked Corn, ,

We compared raw, roasted, and pressure-flaked com in dry matter and starch digestion studies in vitro. For dry matter digestion, incubations were 1, 4, 8, 16, 24 and 48 h. Dry matter digestion was increased in hours 1 through 24 by processing. Digestion in the 48-h period was decreased by processing which suggests that processing may increase the ease of utilization but not total utilization. Roasting decreased 48-h dry matter digestion more than pressure flaking. Starch digestion with incubations 1, 4, 24, and 48 h favored processed corn at all hours except 4. The 48-h observations from both studies indicate that while processing enhances starch utilization, it impairs utilization of other components in the grain. Prediction equations for dry matter and starch digestion for each corn treatment from length of incubation period and squared length of incubation period had multiple correlations of .96 or greater.     

Mineral contents of some southern Italian wines I. Determination of B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb by inductively coupled plasma atomic emission spectrometry (ICP-AES)

Summary Using a new analytical technique, the inductively coupled plasma atomic emission spectroscopy (ICP-AES), 51 red and rose wines from D.O.C. areas of Southern Italy were measured for the following 14 elements: B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb.Among these elements the most abundant were Si with an average value of 19.60 mg/l, Fe 5.87 mg/l, B 5.19 mg/l, Al 2.13 mg/l and Mn 1.40 mg/l; Cu, Zn and Sn were present in average quantities between 0.10 and 1.00 mg/l; the remaining elements had average concentrations below 0.10 mg/l.

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Gehalt an Spurenelementen in einigen D.O.C.-Weinen aus Süditalien I. Quantitative Bestimmung von B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb durch ICP Atomemissions-Spektrometrie

Zusammeufassung Unter Anwendung emer neuen analytischen Methode, ICP Atomemissions-Spektrometrie, wurden in 51 Rot- und Rosé-D.O.C.-Weinen aus Süditalien, die folgenden 14 Elemente bestimmt: B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb.Unter diesen Elementen sind Si mit einem Mittelwert von 19,60 mg/l, Fe mit 5,87 mg/l, B mit 5,19 mg/l, Al mit 2,13 mg/l und Mn mit 1,40 mg/1 die häufigsten. Die mittleren Konzentrationswerte für Cu, Zn und Sn liegen zwischen 0,10 und 1,00 mg/l; während die der restlichen Elemente unter 0,10 mg/l sind.

     

Varied Composition of Tocochromanols in Different Types of Bran: Rye,Wheat, Oat,Spelt, Buckwheat,Corn, and Rice

The profiles of tocopherol (T) and tocotrienol (T3) homologues in 37 samples of seven different types of bran (rye, wheat, oat, spelt, buckwheat, rice, and corn), available on the Polish market, were studied. Tocochromanols were identified and quantified by reverse phase-high-performance liquid chromatograph/fluorescence detector and reverse phase-ultra performance liquid chromatography-electrospray ionization/mass spectrometry. Only rice bran contained all eight tocochromanol types. Corn bran lacked β-T3; rye, wheat, oat, and spelt bran lacked γ-T3 and δ-T3; and buckwheat bran lacked β-T3, γ-T3, and δ-T3. In buckwheat and corn bran tocopherols predominated (98 and 78%, respectively); whereas rye, wheat, oat, spelt, and rice bran were rich in tocotrienols (78, 76, 66, 87, and 66%, respectively). The average total tocochromanol contents in the oat, corn, spelt, buckwheat, wheat, rye, and rice bran were 5.5, 16.2, 15.8, 14.7, 12.8, 10.7, and 9.1 mg/100 g of dry weight, respectively. Tocochromanol concentrations in samples of the same type bran from different sources varied considerably. Better labeling of bran products to reflect this variation would assist with control of vitamin E daily dietary requirements.