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1.
de Boishebert V Urruty L Giraudel JL Montury M 《Journal of agricultural and food chemistry》2004,52(9):2472-2478
In a previous work, the SPME-GC-MS method (chemical analysis) coupled with KSOM-ANN treatment of the results (statistical algorithm) has proved to be efficient to classify 70 strawberry samples harvested in the same year, through the 17 varieties to which they belonged, in a two-dimensional map. As an extension, the present study confirms that these results were not dependent on the year of strawberry production and discusses what effects were observed between results obtained in different years. Samples of different strawberry varieties were harvested during the three campaigns of 2000, 2001, and 2002 and analyzed independently. The chemical data matrix obtained in each case allowed the verification of the proposal that the same discriminative effect could be obtained independently of the year of production by using maps of different sizes. Therefore, 30 measures obtained from samples of 9 varieties in 2000, 54 measures from 13 varieties in 2001, and 80 measures from 20 varieties in 2002 were correctly classified by using 20, 35, and 56 hexagon maps, respectively. In a second analysis based on the 2002 production, the chemical differences between variety aromatic features were noted through the increasing size of the map used. Finally, results relative to 7 varieties cultivated in 2001 and 2002 and stored under exactly the same conditions were computed together for elaborating a single map. An interesting effect of double classification according to the year and the varieties was observed. 相似文献
2.
针对目前玉米品种抗倒伏鉴定方法费时、费力，玉米抗倒伏品种选育周期长的问题，该研究采用高光谱成像技术结合统计学习方法在玉米营养生长期开展品种抗倒伏预测。于2018年和2019年开展田间试验采集不同抗倒伏的8个玉米品种的高光谱成像数据，基于区域识别方法提取感兴趣区域（Region of Interest，ROI）的光谱曲线，分析抗倒样本和不抗倒样本的数据特性；然后分别采用过滤式特征选择算法ReliefF（Relevant Features）和主成分分析（Principal Component Analysis，PCA）结合ReliefF算法的方式，挖掘抗倒品种和不抗倒品种的光谱分类特征；最后使用交叉验证的方式，对ReliefF方法选择的原始光谱数据特征数量和PCAReliefF方法选择的主成分特征数量进行优化，分别建立ReliefF-SVM和PCAReliefF-SVM支持向量机（Support Vector Machines，SVM）分类模型，并对SVM模型的惩罚参数和核参数进行优化，以获得更好的模型预测效果。结果表明：经过特征优化，2018年试验和2019年试验分别选择了40和50个特征参与建模，且使用PCAReliefF方法选择的主成分特征与使用ReliefF方法选择的原始光谱数据特征相比，几乎不含有冗余特征；通过对支持向量机模型的惩罚参数和核参数进行优化，2018年试验ReliefF-SVM和PCAReliefF-SVM模型对预测集样本的抗倒伏分类预测正确率分别为84.17%和85 %，2019年试验模型分类预测正确率分别为84.17%和85.83%。可见，采用高光谱成像数据和统计学习方法可以实现对玉米品种抗倒伏的早期预测，使用PCAReliefF-SVM模型比ReliefF-SVM分类模型综合性能更优，试验为玉米抗倒伏品种的高效筛选提供了方法和借鉴。 相似文献
3.
Zheng Q Song J Doncaster K Rowland E Byers DM 《Journal of agricultural and food chemistry》2007,55(5):1663-1673
A modified phenol-based protocol and a phenol-free protocol that involves hot SDS extraction followed by TCA precipitation in acetone were qualitatively and quantitatively compared and evaluated on apple peel and strawberry fruit. The phenol protocol resulted in significantly higher protein yields of 2.35 +/- 0.1 and 0.46 +/- 0.06 mg/g of FW from apple and strawberry fruit, respectively, compared to the SDS protocol, which produced 0.74 +/- 0.1 and 0.27 +/- 0.02 mg/g of FW, respectively. 2-DE analysis of apple protein extracts revealed 1422 protein spots associated with the phenol protocol and 849 spots associated with the SDS protocol. Of these, 761 were present only in phenol gels, whereas 23 were exclusive to SDS samples. For strawberry, SDS extraction produced poor-quality spots with a high degree of streaking, indicating possible contamination. The application of a cleanup procedure resulted in a purified protein extract with high-quality spots. 2-DE analysis of strawberry protein extracts revealed 1368 spots for the phenol protocol and 956 spots for the SDS protocol accompanied by the cleanup procedure. Of these, 599 spots were present only in phenol gels, whereas 109 were present only in SDS samples. Spots from each fruit tissue and extraction procedure were selected, and a total of 26 were identified by LC-MS/MS. Overall, this study demonstrates the complexity of protein extraction of fruit tissues and suggests that a phenol-based protein extraction protocol should be used as a standard procedure for recalcitrant fruit tissues, whereas a SDS protocol with or without a cleanup procedure may be used as an alternative protocol. 相似文献
4.
M D Gomes Da Silva H J Chaves Das Neves 《Journal of agricultural and food chemistry》1999,47(11):4568-4573
The aroma compositions of Fragaria ananassa varieties are assessed by purge-and-trap high-resolution gas chromatography. Gas chromatography/mass spectrometry and gas chromatography/Fourier transform infrared spectroscopy allow the identification of 93 components from which 21 are for the first time described as constituents of strawberry aroma. Despite the complexity of the aroma, sensory properties are assigned to 40 components as perceived by three independent testers by application of a sniffing technique to the chromatographic effluent. The data are used for comparative sensory characterization of strawberry varieties by means of principal component analysis. 相似文献
5.
6.
基于稀疏表示的大米品种识别 总被引：4，自引：3，他引：1
为了实现机器视觉准确判别大米品种,提出了一种基于稀疏表示的大米品种识别方法。以长江米、圆江米、粳米、泰国香米、红香米和黑米等6种大米籽粒图像作为研究对象,采用颜色和形态结构参数表示单个籽粒。每种大米随机选取50粒作为训练样本,200粒作为测试样本。所有训练样本组成稀疏表示方法的数据词典,对每一个测试样本,计算其在数据词典上的投影,将具有最小投影误差的类作为测试样本所属的品种。最后将提出的方法与BP网络和SVM的识别结果做了对比和分析。试验结果表明,提出的方法对于6个大米品种的综合识别准确率为99.6%,获得了最好的分类效果。为大米品种的识别提供了一种新的有效方案。 相似文献
7.
玉米品种抗顶腐病遗传多样性分析及其应用 总被引：4，自引：0，他引：4
经鉴定和调查, 从25个玉米品种中选择抗病性较稳定的14个品种为材料, 其中6个品种包括病、健株, 共20个样品, 进行抗病遗传多样性的RAPD分析.结果表明, 不同品种的抗性遗传背景丰富, 20个样品经PCR扩增聚类后, 以遗传距离15划分, 可分为7个类群, 同一类群内的品种在抗病性方面有较强的相似性;同一品种的健株与病株间能产生特异性条带, 且存在一定的遗传距离, 说明植株感病后, 其遗传特性会发生改变.田间试验表明, 遗传特性差异大的感病品种与抗病品种轮作对顶腐病有较高的防效, 可一定程度缓解生产中倒茬难而造成病害流行的难题. 相似文献
8.
Hernanz D Recamales AF Meléndez-Martínez AJ González-Miret ML Heredia FJ 《Journal of agricultural and food chemistry》2008,56(8):2735-2741
Apart from the need to assess the color of foods due to its preponderant role in their acceptability, there is currently a new trend consisting in the study of the relationships between the color and the pigments accounting for it. The color of five strawberry varieties cultivated in two different soilless systems has been studied, and an array of multivariate statistical methods have been performed to single out the color parameters that best discriminate among the different samples surveyed and to correlate them with the pigment content. It is concluded that there is not a direct relationship between the external and flesh colorations of the berries. Additionally, after discriminant methods were applied, it was noticed that, taking into account the strawberry varieties, >90% of the cases could be correctly classified, a noticeably lower percentage of correct classification (around 60%) being obtained when the type of cultivation system was selected as the criterion for discrimination. The best correlations of pigment-color coordinates were found between pelargonidin-3-rutinoside and the external a* (r= -0.87) followed by pelargonidin-3-glucoside and the internal L* (r= -0.72). 相似文献
9.
Casal S Oliveira MB Alves MR Ferreira MA 《Journal of agricultural and food chemistry》2000,48(8):3420-3424
Arabica and robusta roasted coffees from several geographical origins, in a total of 29 samples, were characterized for their contents in caffeine, trigonelline, and nicotinic acid by a recently developed HPLC/diode-array detector method. All samples were subjected to the same roasting procedure in order to eliminate the variations due to this process. Characterization was achieved by applying multivariate and nonparametric analysis to the chromatographic results. The two coffee varieties were clearly separated by their trigonelline and caffeine contents. Nicotinic acid could not be used as a variety discriminate factor. There was no association with the geographical origin of the samples. 相似文献
10.
基于深度卷积神经网络的田间麦穗密度估计及计数 总被引：8，自引：8，他引：0
小麦的最终产量可由单位面积的小麦麦穗数侧面反映,为了快速准确统计小麦麦穗数,该研究给出一种在单幅图像上利用深度卷积神经网络估计田间麦穗密度图并进行麦穗计数的方法。首先对采集的田间小麦图像进行直方图均衡化及阈值分割预处理,以减少图像中光照及一些复杂背景对计数的影响;然后根据灌浆期田间小麦图像麦穗密集的特点,引入拥挤场景识别网络（Congested Scene Recognition Network,CSRNet）构建麦穗密度图估计模型,并采用迁移学习方法,利用小麦图像公开数据集对模型进行预训练,再用所采集的小麦图像数据集进行模型参数调整和优化;利用得到的模型生成单幅小麦图像的麦穗密度图,根据密度图中所有密度值的总和对图像进行麦穗计数。最后根据对单幅麦穗图像的试验数据,构建田间麦穗计数函数模型,实现田间小麦麦穗数估计。通过对所采集的安农170、苏麦188、乐麦608和宁麦24这4个品种共296幅小麦图像进行试验,平均绝对误差（Mean Absolute Error,MAE）和均方根误差（Root Mean Squared Error,RMSE）分别为16.44和17.89,4个品种小麦的麦穗计数值与真实值的决定系数R2均在0.9左右,表明该方法对单幅图像小麦麦穗计数精度较高。此外,通过对田间小麦麦穗数进行估计试验,结果表明,随面积的增大麦穗估计的误差越小,研究结果可以为小麦的产量自动估计提供参考。 相似文献
11.
Del Campo G Santos JI Iturriza N Berregi I Munduate A 《Journal of agricultural and food chemistry》2006,54(8):3095-3100
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
12.
Saucedo-Hernández Y Lerma-García MJ Herrero-Martínez JM Ramis-Ramos G Jorge-Rodríguez E Simí-Alfonso EF 《Journal of agricultural and food chemistry》2011,59(8):4125-4129
Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), followed by multivariate treatment of the spectral data, was used to classify seed oils of the genus Cucurbita (pumpkins) according to their species as C. maxima, C. pepo, and C. moschata. Also, C. moschata seed oils were classified according to their genetic variety as RG, Inivit C-88, and Inivit C-2000. Up to 23 wavelength regions were selected on the spectra, each region corresponding to a peak or shoulder. The normalized absorbance peak areas within these regions were used as predictors. Using linear discriminant analysis (LDA), an excellent resolution among all categories concerning both Cucurbita species and C. moschata varieties was achieved. The proposed method was straightforward and quick and can be easily implemented. Quality control of pumpkin seed oils is important because Cucurbita species and genetic variety are both related to the pharmaceutical properties of the oils. 相似文献
13.
Volatile compounds were isolated from strawberry guava fruit by simultaneous steam distillation-solvent extraction according to Likens-Nickerson. Compounds were identified by capillary GC-MS and sensorially characterized by sniffing GC. Two hundred and four compounds were identified in the aroma concentrate, of which ethanol, alpha-pinene, (Z)-3-hexenol, (E)-beta-caryophyllene, and hexadecanoic acid were found to be the major constituents. The presence of many aliphatic esters and terpenic compounds is thought to contribute to the unique flavor of the strawberry guava fruit. 相似文献
14.
The flowers of strawberry plants grow on very variable branched structures called inflorescences, in which each branch gives
rise to 0, 1, or 2 offspring branches. We extend previous modeling of the number of strawberry flowers at each individual
level in the inflorescence structure conditional on the number of strawberry flowers at the previous level. We consider a
range of logistic regression models, including models that incorporate inflorescence effects and random effects. The models
can be used to summarize the overall structure of any particular variety and to indicate the main differences between varieties.
For the data of the article, we show that models based on convolutions of correlated Bernoulli random variables outperform
binomial regression models. 相似文献
15.
基于BP神经网络的脱绒棉种品种识别 总被引：2，自引：1，他引：1
摘要：为了提高脱绒棉种品种识别的准确率,提出了基于BP神经网络的非线性识别方法。该文以新路早36、中棉50、惠远710等3个品种为研究对象,基于图像处理技术提取了脱绒棉种的颜色和形状特征参数,后又通过对特征参数进行单因素分析选取了差别较明显的9个特征参数参与网络的训练,提高了训练速度。经训练比较得出,当训练目标为0.02,训练次数为3 000,隐含层的结点数为12时,模型的训练误差最小。经过对测试集进行测试,得出综合测试准确率为90%,证明了该方法是可行的,提高了脱绒棉种的识别准确率。该研究可为其他粒状种子品种识别提供参考。 相似文献
16.
A model based on neural networks has been designed to detect lampante virgin olive oils, a category of olive oil that cannot be consumed without a previous refining process according to the current regulation of the European Communities. The response of 7 metal oxide sensors analyzing 114 olive oil samples has been used in the design, training, and internal validation of the neural network with only 4.5% error in validation. The designed mathematical model, the equations of which are fully described, has been validated also with an external set of 13 samples of diverse varieties and geographical origins with 100% correct classification. 相似文献
17.
种质资源鉴定是研究与利用冬瓜种质资源的基础。为了明确冬瓜种质资源遗传多样性,本研究基于表达序列标签-简单重复序列(EST-SSR)分子标记的人工绘制品种鉴别示意图(MCID)法鉴定40份冬瓜种质资源。利用筛选出的7对引物对冬瓜种质资源进行PCR扩增,应用MCID法构建冬瓜品种鉴定图。结果表明,利用7对引物扩增的特征性谱带能够将冬瓜品种在分子水平上区分开,同时能够构建40份冬瓜种质资源的品种鉴定图。利用Ntsys2.10e软件进行聚类分析,在遗传相似系数0.77处,将冬瓜资源分为3个类群。品种鉴定图能够快速地找到区分品种的引物,比聚类图更加直观。基于EST-SSR标记的MCID法是一种有效的冬瓜资源鉴定方法。本研究对冬瓜资源鉴定具有重要意义。 相似文献
18.
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
19.
基于机器视觉的多个玉米籽粒胚部特征检测 总被引：6，自引：4，他引：2
为了利用机器视觉进行多个玉米种子品种的自动识别,该文提出了一种针对多个玉米籽粒进行胚部检测的方法。该方法基于阈值分割和形态学,在RGB空间,采用自动屏蔽0值像素的大津法（Otsu法）,根据B分量值对多粒玉米籽粒扫描图像进行分割,并采用改进的开闭运算对分割后的图像进行修整,最终得到多个玉米籽粒胚部区域。以4个黄玉米品种各45个籽粒为实验对象,以此方法进行胚部检测,为了验证所得胚部区域有效,提取胚部区域面积、周长分别与手工测量的面积、周长进行线性回归分析,R2的均值分别达到0.9834、0.9578;进一步提取所得胚部区域的形状参数,进行聚类识别,不同品种间的差距值反映了不同品种胚部视觉效果上的差异大小,4个品种中1种识别率为97.8%,其余3种均为100%;多个玉米胚部检测较每个籽粒单独处理的效率提高了29.59%。试验结果表明本文提出的多个玉米籽粒胚部检测方法可行。此研究结果为进一步研究玉米籽粒的胚部特征提供了有利条件,也为实现玉米品种的快速准确分类提供了参考。 相似文献
20.
Gavrilova V Kajdzanoska M Gjamovski V Stefova M 《Journal of agricultural and food chemistry》2011,59(8):4009-4018
The phenolic profile of four blueberry varieties (Vaccinium corymbosum L., cv. Toro, Legacy, Duke and Bluecrop) and two varieties (Rosenthal and Rovada) of red currants (Ribes rubrum L.) and black currants (Ribes nigrum L.) cultivated in Macedonia have been analyzed using HPLC coupled to diode-array detection and tandem mass spectrometry with electrospray ionization. A complex profile of anthocyanins, flavonols, flavan-3-ols and hydroxycinnamic acid derivatives has been assayed in acetone-acetic acid (99:1, v/v) extracts. Anthocyanins comprised the highest content of total phenolic compounds in currants (>85%) and lower and variety dependent in blueberries (35-74%). Hydroxycinnamic acid derivatives comprised 23-56% of total phenolics in blueberries and 1-6% in currants. Chlorogenic acid was the major hydroxycinnamic acid in blueberries, only in the Legacy variety, two malonyl-caffeoylquinic acid isomers were major components. Flavonols, mainly quercetin and myricetin glycosides, were a minor group, but glucosides of laricitrin and syringetin were also detected in the blueberry varieties counting for 10-34% of total flavonols. From flavan-3-ols, catechin was detected in most samples; the dimer B2 was specific for blueberries whereas epigallocatechin was detected in currants. 相似文献