电感耦合等离子体原子发射光谱法直接进样测定花生油中的锌

采用电感耦合等离子体原子发射光谱法(ICP- AES)测定花生油中锌的含量.使用甲基异丁基酮(MIBK)作稀释剂,优化全谱型ICP-AES分析条件测定花生油中锌的含量,检出限为0.030 mg/L.用此方法测定花生油中0.30 mg/kg～100 mg/kg的锌含量,测定结果准确、可靠,连续测定6个平行样,检测结果的相对标准偏差均小于2.0％.     

液相色谱-串联质谱法分析噻虫嗪在菜薹上的残留行为

为了明确噻虫嗪在菜薹上使用后的残留行为，在6个省市开展了噻虫嗪在菜薹上的最终残留试验，在其中2个省份开展了消解动态试验。样品采用固相萃取柱净化，高效液相色谱-串联质谱法(HPLC-MS/MS)测定，外标法定量。结果表明：添加水平在0.01～1.0 mg/kg下，噻虫嗪及其代谢物噻虫胺在菜薹中的添加回收率为89%～102%和93%～100%，相对标准偏差为5.8%～8.5%和4.0%～9.5%，定量限(LOQ)为0.01 mg/kg。消解动态试验结果表明，山东和安徽两地噻虫嗪在菜薹上的降解半衰期分别为1.8 d和1.2 d;6个省市的最终残留试验结果显示，用药量56.25～84.375g a.i./hm²，施药2～3次，药后10 d，收获的菜薹中噻虫嗪的残留量为2，最多施药2次，推荐安全间隔期为7 d。     

3%阿维菌素ME在梨和土壤中残留动态研究

研究3%阿维菌素ME在梨和土壤中的残留动态情况,为其在梨上安全合理使用提供科学依据。笔者采用柱前衍生高效液相色谱法,测定阿维菌素在梨和土壤中的残留消解动态和最终残留量。结果表明,方法的灵敏度、准确度和精密度符合残留检测要求;阿维菌素在梨和土壤中降解半衰期分别为1.1~2.6天和2.1~5.7天;梨中阿维菌素的最终残留量最高为0.0090 mg/kg、土壤中最高为0.0157 mg/kg。中国规定梨中阿维菌素的最大残留限量值(MRL)0.02 mg/kg,以此依据,3%阿维菌素微乳剂用于防治梨木虱,于梨木虱若虫发生期田间喷雾,施药剂量不超过18 mg a.i./kg,施药3~4次,安全间隔期为7天。     

百菌清在不同季节设施蔬菜上的残留降解规律研究

研究了山东省不同季节设施黄瓜和番茄上百菌清的残留状况与残留降解规律,评价百菌清的安全性。结果表明：残留消解动态符合方程Ct=C0e-kt,在春秋两季黄瓜中的半衰期为2.1~5.2天,番茄中的半衰期为3.1~6.0天。300~600倍液施药水平下,施药2~3次,施药间隔为7天,末次施药7天后,百菌清在黄瓜上的残留量为3.101~0.912 mg/kg,在番茄上的残留量为4.093~1.071 mg/kg,残留量低于联合国食品法典委员会(CAC)规定的最大残留限量值(MRL)5.0 mg/kg。百菌清的降解具有明显的季节性差异,按照推荐剂量用药,春季的安全间隔期应在7~10天,秋季应在10~14天。     

清水江河谷柑橘园树体与土壤养分状况分析

试验对贵州清水江河谷地区柑橘果园不同品种叶片中N、P、K、Ca、Mg、Fe、Mn、Cu、Zn含量和土壤养分进行了分析测定和评价。结果表明:该地区柑橘叶片中N、P、K、Ca、Mg元素含量范围分别为3.05～3.86g/100g.DW、0.144～0.238g/100g.DW、0.71～1.80g/100g.DW、2.09～4.54g/100g.DW、0.06～0.17g/100g.DW,叶片中Fe、Mn、Cu、Zn元素含量范围分别为127.88～211.80mg/kg.DW、34.24～78.58mg/kg.DW、8.65～15.14mg/kg.DW、7.45～11.32mg/kg.DW。树体中Mg、Zn元素含量较低,处于缺乏状态;N、P元素含量普遍偏高。柑橘园土壤全N含量范围为0.106～0.117g/100g,土壤速效P、K含量范围分别为5.95～43.81mg/kg、29.91～149.77mg/kg。土壤有效Fe、Mn、Cu、Zn含量范围分别为11.79～54.54mg/kg、8.60～49.49mg/kg、0.08～0.78mg/kg、0.46～1.54mg/kg,土壤有效Fe、Mn、Cu、Zn含量严重缺乏。     

螺虫乙酯在黄瓜及其土壤中残留量检测方法及残留规律研究

[目的]本文旨在研究黄瓜和土壤中螺虫乙酯残留量的高效液相色谱测定方法,并于2014年用该方法测定湖南、浙江和广东三地螺虫乙酯在黄瓜及其土壤上的消解动态和残留规律试验研究的样品。[方法]样品用乙腈提取,高效液相色谱紫外检测器测定。[结果]结果表明：当添加螺虫乙酯在黄瓜及其土壤中的浓度为0.05mg/kg～1.0mg/kg时,平均添加回收率分别为95.75%～98.91%、89.37%～99.78%;变异系数分别为1.26%～2.89%、1.62%～1.99%,该方法对黄瓜和土壤中螺虫乙酯的最低检出浓度为 0.025mg/kg;在自然环境条件下,螺虫乙酯在湖南、浙江和广州三地的黄瓜和土壤中的半衰期分别为2.67～8.82d,1.95～6.19d。[结论]按推荐使用剂量对黄瓜施药,末次施药后第5天螺虫乙酯在三地的黄瓜和土壤中的残留量均未检出,黄瓜中螺虫乙酯残留量均低于瓜果类的MRL值(0.2mg/kg)。     

10%烯酰吗啉水乳剂在葡萄和土壤上的残留及消解动态研究

本文通过对10%烯酰吗啉水乳剂在葡萄和土壤中残留消解动态和最终残留量的研究。结果表明,以375 mg/L剂量施药4次,距离最后1次施药后21 d,烯酰吗啉最终在葡萄中的残留量均<0.5 mg/kg,在土壤中均<0.7 mg/kg,烯酰吗啉在葡萄和土壤中消解较快,其残留消解动态曲线符合化学反应一级动力学方程。半衰期在葡萄上为9.3～14.8 d,在土壤中为11.2～15.8 d。     

芽菜型荞麦新品种酉荞3号的选育

酉荞3号是按系谱法育成的荞麦芽菜专用新品种.在2013年重庆市荞麦品种春播区试平均单产为120.1 kg/667m2,比对照九江苦养增产3.90％,2013年重庆市荞麦品种秋播区试平均单产112.3 kg/667 m2,减产1.90％,2013年重庆市秋播苦荞麦生产试验平均单产为110.1 kg/667 m2,增产7.94％.全生育期82d,平均株高120 cm,主茎平均分枝4～8个,主茎节数12～16节,单株粒重3.7g,千粒重22.1 g;硒含量为158 μg/kg,粗蛋白含量为11.2％,总黄酮含量为2.5 mg/kg.在荞麦芽菜品种试验中,每100 g酉荞3号种子平均可生产出芽菜224.7 g,较对照品种九江苦荞增产72.7 g,增幅47.8％,芽苗高12.8 cm,脱壳率为92％,收获期、芽苗高、脱壳率等指标均优于对照.芽菜6-苄基腺嘌呤含量＜0.02mg/kg,硒含量为18.6 μg/kg,蛋白质含量为2.4％,脂肪含量为0.4％,总黄酮含量为9.52 mg/kg,纤维素含量为4.15％.适合在重庆市作为荞麦芽菜专用品种进行推广.     

DON净化柱——高效液相色谱法检测粮谷中呕吐毒素

通过自制DON净化柱和高效液相色谱仪,建立了检测谷物中呕吐毒素的方法.样品经乙腈—水溶剂提取后,通过自制的DON净化柱净化,采用C18分离柱和紫外检测器测定.结果表明:样品通过乙腈—水(体积比V/V,84∶16)混合溶剂和超声20 min的提取,可大幅度提高方法回收率;呕吐毒素在0.5 mg/kg～8.0mg/kg内线性关系好,相关系数为0.999;在0.5、2.0和8.0mg/kg的加标水平下,回收率为95.1％～102.3％,相对标准偏差为1.8％～6.4％,检出限(信噪比)为50μg/kg.     

苹果汁中多菌灵的高效液相色谱法分析

建立了苹果汁中多菌灵残留量的高效液相色谱（HPLC）分析方法,样品经乙酸乙酯提取,旋转蒸发仪浓缩,氮气吹干甲醇定容后,采用配有二极管阵列检测器（DAD）的HPLC测定,外标法定量。在添加水平为0．5,1,1．5,3mg/kg时,多菌灵的添加回收率为93．2％～102．7％。该方法对苹果汁中多菌灵的检出限为0．02mg／kg,可以满足苹果汁中多菌灵的残留限量检测要求,并利用该方法对农贸市场上苹果汁中的多菌灵残留量进行了分析。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Variation in forage grasses as hosts of the root-knot nematode Meloidogyne naasi (Franklin) and selection for resistance in ryegrass

Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.     

Current and future strategies in breeding lentil for resistance to biotic and abiotic stresses

Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...