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1.
To provide an efficient and running analytical tool to strawberry plant breeders who have to characterize and compare the aromatic properties of new cultivars to those already known, a HS-SPME/GC-MS analysis method has been coupled with a statistical treatment method issued from the current development of artificial neuron networks (ANN), and more specifically, the unsupervised learning systems called Kohonen self-organizing maps (SOMs). So, 70 strawberry samples harvested at CIREF from 17 known varieties have been extracted by using a DVB/Carboxen/PDMS SPME fiber according to the headspace procedure, and then chromatographed. A panel of 23 characteristic aromatic constituents has been selected according to published results relative to strawberry aroma. The complex resulting matrix, collecting the relative abundance of the 23 selected constituents for each sample, has been input into the SOM software adapted and optimized from the Kohonen approach described by one of the authors. After a period of training, the self-organized system affords a map of virtual strawberries to which real samples are compared and plotted in the best matching unit (BMU) of the map. The efficiency for discriminating the real samples according to their variety is dependent on the number of units selected to define the map. In this case, a 24-unit map allowed the complete discrimination of the 17 selected varieties. Moreover, to test the validity of this approach, two additional samples were blind-analyzed and the results were computed according to the same procedure. At the end of this treatment, both samples were plotted into the same unit as those of the same variety used for training the map.  相似文献   

2.
在大田条件下,探讨了不同降水年型不同水分处理条件下大穗型小麦品种籽粒灌浆及产量的变化。结果表明:通过用不同方程对籽粒生长动态进行拟合,Cubic方程最精确。2000~2001干早年型W和Ws与两个灌浆持续期参数(Se、S)相关性显著.2001~2002丰雨年型W和Ws与3个灌浆速率参数(V、Vs、Vmax)间相关性达显著水平。两年度相比,2000~2001年度籽粒灌浆持续期短,灌浆速率小,导致粒重降低。灌水对灌浆参数的效应年际间存在差异,2000~2001年度随灌水次数增多,S和Se延长,灌浆速率降低;而2001~2002年度随灌水次数增多,S和Se缩短,灌浆速率以灌—水处理最小.灌两水处理最高。灌水对产量的影响,2000~2001年度显著增产,2001~2002年度处理间无显著差异,灌三水处理较灌两水处理反而减产。  相似文献   

3.
The low field region (5.8-9.0 ppm) corresponding to aromatic protons and the region 1.8-3.0 ppm of the (1)H NMR spectra were used for characterization and chemometric differentiation of 52 apple juices obtained from six cider apple varieties. The data set consisted of 14 integrated areas corresponding to resonances from acids and phenolic compounds. Multivariate procedures based on hierarchical cluster and discriminant analysis were performed on selected signals of the spectra to determine whether it was possible to distinguish the different juices. Cluster analysis was able to satisfactorily classify the six apple varieties. Discriminant analysis, by means of stepwise procedure for variables selection and leave-one-out for cross-validation, was applied to 40 samples from the year 2001, obtaining recognition and prediction abilities of 100%. The most discriminant variables corresponded to poliphenols, (-)-epicatechin, phloridzin-phloretin, and p-coumaric, chlorogenic, and malic acids. The classification model was applied to 12 samples from apples harvested in the years 2002 and 2003, and the prediction ability was 91.7%.  相似文献   

4.
In the period from 2000 to 2002, studies on peppermint (Mentha x piperita) herb and essential oil (EO) production have been conducted at Planteforsk, Apelsvoll Research Centre Div. Kise in Norway. The trials were aimed at finding the optimal harvest date and suitable drying methods to maximize EO yield and to obtain a desirable oil quality. Peppermint plants from the first production year (2000 and 2001) and the second production year (2002) were harvested during flowering at three developmental stages (early, full, and late bloom). Biomass and leaf production were recorded, and the water content of the plant material was detected after the application of different drying methods: instantaneous drying at 30, 50, and 70 degrees C and prewilting (ground drying) for 1 or 5 days followed by final drying at 30 degrees C. Finally, plant samples were transferred to The Plant Biocentre at NTNU, Trondheim, Norway, for hydrodistillation and gas chromatography-mass spectrometry (GC-MS) analyses of the EOs. Peppermint oil yield increased from early to full bloom and late bloom (average of all years and drying methods except for 50 and 70 degrees C: 2.95, 4.13 and 4.20 L/daa, respectively) as an effect of biomass production and leaf growth. The flavor-impact compounds, menthol and menthone, reached their optimum at full bloom (43-54 and 12-30%, respectively). Prewilting led to slight decreased EO levels after 1 day (7.7%) and 5 days of ground drying (1.5%) and no EO quality changes, compared to direct drying at 30 degrees C. The plant weight (H2O content) was drastically decreased to the average under 80 and 45% in all years, thus reducing the energy supply and costs for the necessary final drying step.  相似文献   

5.
To determine their influence on leaf tipburn incidence and yields six nutrient solutions with different proportions of potassium (K), calcium (Ca), and magnesium (Mg) were tested in ‘Camarosa’ strawberry plants. Response models were made to predict tipburn incidence, yields and fruit weight. A high Ca proportion in the nutrient solution was determinant for high yields in the first season, while a high Mg content was fundamental for high marketable yields during the two last seasons. In 2001 and 2002, the average fruit weight was higher with high Mg levels, and in 2000 the lowest fruit weights coincided with low levels of Ca in the nutrient solution. The models for tipburn incidence in 2000 and 2002 indicated that solutions with intermediate to high levels of Mg and intermediate to low levels of Ca resulted in a more frequent incidence of tipburn. Conversely, in 2001, the highest tipburn incidence appeared with high K contents.  相似文献   

6.
安徽省冬小麦品种生态气候适宜性分析和精细化区划   总被引:5,自引:0,他引:5  
利用安徽省78个气象站1971-2000年冬小麦生长阶段气象资料和地理信息,选取影响冬小麦品种分布和生长的主要气象因子建立区划指标,采用多元回归模型和GIS空间内插技术对指标要素栅格化,并通过温度和水分两级指标,形成千米网格的安徽省冬小麦品种生态气候适宜性精细化区划图,用安徽省耕地数据掩膜(mask)得到相应耕地意义的区划分布图,并进行分区评述。结果表明,以气温和降水为指标,可将安徽省冬小麦品种的生态气候适宜性划分为5大区11个亚区,分区结果能反映气候变暖背景下安徽省冬小麦生态气候适宜性的分布特点以及各区域温度适宜性和水分适宜性的差异。因冬季气温的南北差异,安徽省适宜种植的冬小麦品种自北向南冬性程度降低。冬小麦生产中的主要问题是水分失衡,北部水分不足,南部过多,制约了稳产高产。根据区划结果,应增强北部冬小麦主产区的抗旱能力,适当扩大沿淮和江淮丘陵北部地区半冬性品种种植面积,尽量压缩南部地区冬小麦种植面积,以全面提高安徽省冬小麦生产水平。  相似文献   

7.
余莉  底艳  王军  曹淑娟 《农业工程学报》2005,21(13):119-122
土地整理在促进土地合理利用,实现耕地总量动态平衡方面具有重要作用。中国的土地整理于20世纪90年代后期正式提出和运作,预计国家每年将有近20亿元资金用于土地整理项目,如何合理使用这笔专项资金,编制科学合理的土地整理项目预算显得尤为重要。该文以2000年、2001年和2002年三批近200个中央承担土地整理项目为基础,深入剖析了这些项目预算编制中存在的问题及其产生原因,并提出了进一步完善预算编制的建议与措施,以期为资金使用的合理性和规范性提供科学依据。  相似文献   

8.
红壤地区草-牛-沼生态系统中养分循环利用的研究   总被引:4,自引:0,他引:4  
在中度熟化的红壤岗地上采取种植黑麦草和玉米饲喂肉牛,牛粪尿沼气发酵后的沼肥与化肥配施养草的方式,并以单施化肥养草喂牛的方式为对照,进行2年试验研究草-牛-沼生态系统中的养分循环。结果表明,沼肥与化肥配施处理玉米植株的产量和养分积累量都高于单施化肥处理,而黑麦草产量和养分积累量都稍低于单施化肥处理,但由于配施沼肥可节省一半的化肥投入,其效益都很显著。牛对不同施肥处理同种饲草中养分的消化率差异不显著,牛粪尿对养分的回收率也差异不明显,但不同种或同种而收获期不同的饲草消化率和回收率都差异明显。牛粪尿经沼气发酵后回收的养分量可节约饲草生产中近一半的化肥投入。且沼肥施用后土壤肥力得以保护和改善,为后续的饲草生产提供了较好的土壤条件,从而有利于养分循环利用。  相似文献   

9.
土地整理项目预算编制中有关问题的探讨   总被引:2,自引:0,他引:2  
余莉  底艳  王军  曹淑娟 《农业工程学报》2005,21(Z1):119-122
土地整理在促进土地合理利用,实现耕地总量动态平衡方面具有重要作用.中国的土地整理于20世纪90年代后期正式提出和运作,预计国家每年将有近20亿元资金用于土地整理项目,如何合理使用这笔专项资金,编制科学合理的土地整理项目预算显得尤为重要.该文以2000年、2001年和2002年三批近200个中央承担土地整理项目为基础,深入剖析了这些项目预算编制中存在的问题及其产生原因,并提出了进一步完善预算编制的建议与措施,以期为资金使用的合理性和规范性提供科学依据.  相似文献   

10.
Fruits from seven different varieties of Olea europaea L., grown in the same environmental conditions, were harvested in two succeeding years at the same ripening degree and immediately processed. The oils obtained were submitted to gas chromatographic determination of the volatile compounds extracted by dynamic headspace technique. The results demonstrated that the accumulation of the different metabolites in the oils obtained from the various cultivars were strictly connected with the varietal parameter because of the enzyme differences genetically determined. This feature made possible the differentiation of the examined cultivars on the basis of the percent of each metabolite from the enzymatic transformation of 13-hydroperoxides of linolenic acid. Oils from Picual and Koroneiki varieties cultivated in Spain and Greece, respectively, showed contents of volatiles very similar to those detected in the oils of the same varieties cultivated in Italy, proving that they were not significantly influenced by the environmental conditions.  相似文献   

11.
Glyphosate-tolerant alfalfa (GTA) was developed to withstand over-the-top applications of glyphosate, the active ingredient in Roundup agricultural herbicides. As a part of the safety assessment, GTA (designated J101 x J163) was grown under controlled field conditions at geographically diverse locations within the United States during the 2001 and 2003 field seasons along with control and other conventional alfalfa varieties for compositional assessment. Field trials were conducted using a randomized complete block design with four replication blocks at each site. Alfalfa forage was harvested at the late bud to early bloom stage from each plot at five field sites in 2001 (establishment year) and from four field sites in 2003 (third year of stand). The concentration of proximate constituents, fibers, amino acids, coumestrol, and minerals in the forage was measured. The results showed that the forage from GTA J101 x J163 is compositionally equivalent to forage from the control and conventional alfalfa varieties.  相似文献   

12.
Polygonum tinctorium Ait. is a herbaceous subtropical annual plant, belonging to the family Polygonaceae. Within the cells of its leaves P. tinctorium accumulates large amounts of a colorless glycoside, indican (indoxyl beta-d-glucoside), from which the blue dye indigo is synthesized. P. tinctorium is well-known in Japan, where it had been cultivated to produce natural indigo for textile dyeing, whereas it represents a potentially interesting new crop in Europe. To better understand the effects of environmental parameters on P. tinctorium crop production and indigo yield, field experiments were carried out in central Italy under temperate climate. Three lines were tested during the 2001 and 2002 growing seasons, and plant/leaf yields as well as indican contents were evaluated. The results showed that P. tinctorium grown in temperate climate conditions can be harvested three times a year. Yields of 82 and 120 t ha(-1) of fresh plant yield were obtained in 2001 and 2002, respectively. The contrasting weather conditions between the two years significantly affected biomass production, which was higher in the 2002 season, characterized by wet weather conditions. The cycle length from sowing to the last harvest was accomplished in 229-238 days when plants had accumulated 2017-2018 degrees C. Green leaves accounted for 40-45% by weight of fresh plant tissue and contained 11-20 g kg(-1) indican. The three lines did not significantly differ in the main productive parameters or in fresh leaf indican content (14.1 g kg(-1) mean value). Photosynthetic active radiation influences indican leaf production according to the model y = 0.0004x + 8.566 (P < 0.01, correlation coefficient = 0.818). Indican content ranged from 12 to 25 g kg(-1) of fresh leaves with PAR daily values from 10000 to 40000 mEinstein m(-2) (recorded in May and at the end of July-beginning of August, respectively). The results indicate that in nonlimiting rainfall conditions a very high indican content and a potentially high indigo yield can be obtained by cultivating P. tinctorium in this pioneer geographical area.  相似文献   

13.
Tansy (Tanacetum vulgare L.) was cultivated at the Norwegian Crop Research Institute at the Apelsvoll Research Centre, Division Kise, in the period from 2000 to 2001. The study focused on different harvesting regimens for high biomass production and essential oil (EO) yield and quality. Two tansy genotypes from Canada (Richters and Goldsticks) and three Norwegian genotypes (Steinvikholmen, Alvdal, and Brumunddal) were studied. The Canadian genotypes reached a height of 130-145 cm and showed a higher dry weight of aerial plant parts compared to the Norwegian plants in 2000. Similar oil yields could be observed for the Canadian types and genotype Steinvikholmen in the range of 30.8-34.6 L/ha when the plants were harvested twice during budding and before flowering after regrowth (year 2001). In contrast, single harvesting at the full bloom stage resulted in higher oil yields, between 42.1 and 44.5 L/ha (Canadian genotypes), whereas 21.0-38.4 L/ha was obtained from the Norwegian types. Tansy genotypes could be grouped into the following chemotypes: the mixed chemotypes Steinvikholmen (thujone-camphor), Alvdal (thujone-camphor-borneol), Goldsticks (thujone-camphor-chrysanthenyl type), and Brumunddal (thujone-camphor-1,8-cineole-bornyl acetate/borneol-alpha-terpineol) and the distinct chemotype Richters, with average concentrations of (E)-chrysanthenyl acetate >40% in both leaf and flower EO.  相似文献   

14.
Six strawberry (Fragaria x ananassa Duch.) varieties, Senga Sengana, Jonsok, Polka, Korona, Bounty, and Honeoye, were studied in relation to composition of their volatile headspace compounds collected by dynamic purge-and-trap concentration. Also, the influence of cultivation technique on the volatile compounds was tested by comparing conventionally and organically cultivated strawberry varieties. In addition, the effect of geographical origin on strawberry volatiles was investigated. The emphasis of this study was lay in the industrial utilization of strawberry. A total of 52 different volatile compounds were determined from frozen strawberries grown in 1997 and 1998. In addition to individual compounds, total areas of chromatogram profiles were compared. The major esters were found to be methyl butanoate, ethyl butanoate, methyl hexanoate, and ethyl hexanoate. With the application of principal component analysis and analysis of variance to the data matrix, the varieties were classified into three groups. Var. Honeoye was most different from the others. Organic cultivation had no effect on strawberry volatiles.  相似文献   

15.
甘蓝型油菜硼高效基因等位性检测   总被引:1,自引:1,他引:1  
甘蓝型油菜 8Z05和青油 10号为硼高效品种 ;Bakow 为硼低效品种。 2000~2001年度 ,硼高效品种 8Z05青油 10号F2代 588个单株种植在缺硼土壤上。花期调查缺硼症状 ,表现硼高效的单株数与硼低效的单株数之比为 574∶14 ;结实期分离规律与花期相似。这说明甘蓝型油菜硼高效品种 8Z05和青油 10号硼营养高效主效基因是等位的 ,同时可能存在微效基因的修饰作用 ,但微效基因的QTL可能不完全相同。 2个年度的试验结果一致。  相似文献   

16.
气候变化和品种更替对东北地区春玉米产量潜力的影响   总被引:11,自引:4,他引:7  
东北地区是中国重要的粮食生产基地。近50 a中国东北地区正经历着一次显著的增温过程,年平均气温每10a增加0.38℃。明确气候变化对东北春玉米产量的影响以及新品种对产量的贡献对实际生产有重要的指导意义。该文利用通过参数调试与验证后的APSIM-Maize模型,对吉林梨树县春玉米的产量潜力进行模拟分析,解析了不同年代育成的玉米品种的产量潜力,明确了气候变化对春玉米产量潜力的影响以及品种对增产的贡献。结果表明,假设1961-2010年种植的玉米品种不改变,种植20世纪60年代的农家种50 a平均产量潜力为7 879 kg/hm2,种植70年代育成品种50 a平均产量潜力为11 482 kg/hm2,种植80年代育成品种50 a平均产量潜力为12 148 kg/hm2,种植90年代育成品种50 a平均产量潜力为13 400 kg/hm2,种植2000年以后育成的玉米品种50 a平均产量潜力为14 139 kg/hm2,随玉米品种育成年代的后移而增大;1961-2010年随着新品种的育成而不断更替品种时,产量潜力50 a平均值为11 537 kg/hm2。在栽培管理措施不改变的条件下,1961-2010年种植同一品种,产量潜力呈下降的趋势,气候变化对玉米产量潜力的影响表现出负效应,减产率在22%~26%,生育阶段内日照时数的下降是产量潜力下降的主要气候因素;当品种不断更替时,玉米的产量潜力呈上升的趋势,新品种的增产贡献率为46.1%~79.0%,品种的改良对气候变化的负效应有一定的补偿作用;新玉米品种从开花到成熟生育阶段天数延长,成熟期生物量和收获指数增大有利于产量的提高。  相似文献   

17.
不同比例尺农用地分等图件数据自动汇总技术研究   总被引:4,自引:4,他引:0  
基于GIS手段,在农用地分等成果省级汇总过程中,从迅速实现半自动制图综合、部分关键参数和系数的获取,快速自动实现图层间图斑上下级关系索引、保持各农用地图层数据之间的等别不缺失等几个关键过程的技术层面对不同比例尺农用地分等成果汇总的快速自动实现方法进行研究。着重对最近邻法的原理与方法进行了阐述,并应用其对农用地图件进行了处理,实现只有少量人为参与的不同比例尺农用地分等图件图斑的计算机自动匹配过程。结果表明,研究成果可以在提高农用地图件自动综合处理能力、快速建立不同图层间图斑对应关系、各级别图件的等别序列一致性调整等方面工作朝着自动化流程处理、精确化表达的方向更进一步。  相似文献   

18.
Abstract

The main objective of this study was to develop a Geographic Information Systems-based model for land suitability assessment for guava, olive and date palm in the North-western coast of Egypt. Soil, climatic and landscape database as well as satellite image have been integrated through Geographic Information Systems (GIS). A Landsat ETM+ image dated 2001, was classified using maximum likelihood classifier to produce land use/land cover map. Physical and chemical analyses of 57 soil profiles were interpolated to produce continuous land characteristic maps that are relevant to the requirement of the considered crops. These maps with climate and land cover map were integrated using GIS to produce land suitability maps for guava, olive and date palm. Two types of land suitability maps were produced in this study namely: Continuous land suitability maps and conventional land suitability classified maps. For each of them six land suitability maps were produced for the three crops in which three are for actual land suitability and the other three for potential land suitability. It was found that the suitability was higher for date palm followed by olive and the lowest suitability was assigned for guava.  相似文献   

19.
Previous studies have shown that the composition of glyphosate-tolerant soybeans (GTS) and selected processed fractions was substantially equivalent to that of conventional soybeans over a wide range of analytes. This study was designed to determine if the composition of GTS remains substantially equivalent to conventional soybeans over the course of several years and when introduced into multiple genetic backgrounds. Soybean seed samples of both GTS and conventional varieties were harvested during 2000, 2001, and 2002 and analyzed for the levels of proximates, lectin, trypsin inhibitor, and isoflavones. The measured analytes are representative of the basic nutritional and biologically active components in soybeans. Results show a similar range of natural variability for the GTS soybeans as well as conventional soybeans. It was concluded that the composition of commercial GTS over the three years of breeding into multiple varieties remains equivalent to that of conventional soybeans.  相似文献   

20.
The substrate specificity of alcohol acyltransferase (AAT) enzymes from different strawberry varieties was studied. Proteins with AAT activity from fruits of Fragaria x ananassa Duch. cv. Oso Grande were purified to apparent homogeneity and used for kinetic studies with different straight-chain alcohols and acyl-CoAs. K(m) values obtained for Oso Grande enzyme with six different alcohols, using acetyl-CoA as cosubstrate, decreased with increasing length of the alcohol chain. In similar experiments the increase in the acyl-CoA carbon chain was also found to be correlated with a higher substrate specificity. Heptanol (K(m) = 0.73 mM) and hexanoyl-CoA (K(m) = 0.41 mM) were the best substrates for Oso Grande AAT. Comparative catalytic studies were carried out with AAT partially purified extracts from the wild type Fragaria vesca and five commercial strawberry varieties: Tudnew, Carisma, Camarosa, Sweet Charlie, and Eris. The specificities of these enzymes toward five selected alcohols and acyl-CoAs reflected interesting cultivar differences.  相似文献   

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