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1.
This study determined the indirect selection index of doubled haploid(DH) rice using a multivariate analysis approach to select lines adaptive to salinity stress, comprising three experiments. The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor, Indonesia. The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl, conducted at a greenhouse in Bogor. The third experiment involved the validation of the indirect adaptability selection index(IASI) through a field experiment in Sukra(saline area). Field experiments followed a randomized complete block design(RCBD), whereas an RCBD nested factorial design was used for the greenhouse experiment. The first and second experiments used 56 DH lines and four check varieties with three replications. In the second experiment, Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity, respectively. The third experiment used 28 selected DH lines, Inpari 29 and one sensitive DH line. The good agronomic index(GAI) was 0.465 yield + 0.433 number of productive tillers + 0.31 number of filled grains. This generated 24 DH rice lines with good agronomic traits. The salinity tolerance index(SaTI) was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis. This generated 34 DH rice lines with good salinity stress tolerance. The IASI(IASI = GAI – Sa TI) selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation.  相似文献   
2.
以云南滇红玫瑰(ZY)与墨红玫瑰(DH)两种云南主要的食用花卉品种为研究对象,采用超高效液相色谱-串联质谱(UPLC-MS/MS)方法比较两种玫瑰花次生代谢产物的差异性。结果表明,两种花瓣中共检测到82种代谢产物,包括55种氨基酸及其衍生物(67.07%)、16种生物碱(19.51%)、7种酚胺(8.54%)、4种吲哚类生物碱(4.88%),其中滇红玫瑰中谷胱甘肽含量是墨红玫瑰的26.35倍,具有较强的抗氧化能力;而L-天冬酰胺和S-(5'-腺苷)-L-高半胱氨酸却是墨红玫瑰中特有的物质,具有显著的降血压作用。与墨红玫瑰相比,滇红玫瑰15种差异代谢物显著下调,表明墨红玫瑰较滇红玫瑰有较高的营养保健功能,而滇红玫瑰高表达成分使其具有更强的抗氧化能力。  相似文献   
3.
【Objective】The aim of this study was to identify the typical indices of fruit quality and high quality materials of ‘Yangjiaocui’ melons to provide reference and basis for melon quality evaluation and breeding. 【Method】Eighteen indices, including economic trait and flesh quality of fruits from 6 cultivars and 26 high-generation inbred lines of ‘Yangjiaocui’ melons were determined. Based on factor analysis, stepwise regression, correlation analysis and two-dimension ordination map, the typical indices of fruit quality and high quality materials were identified. 【Result】 Among the 18 indices, single fruit mass, hardness, vitamin C (VC) content, titratable acid content, sugar-acid ratio and solid acid ratio showed greater variability, and the variation coefficients were more than 20%. However, the variability of fruit transverse diameter, flesh thickness rate and pH were relatively lower and the variation coefficients were less than 10%. Three common factors were extracted from economic trait indices with 87.71% cumulative variance contribution rate and the explanatory indices were fruit longitudinal diameter, fruit transverse diameter, fruit shape index, fruit cavity longitudinal diameter, fruit cavity transverse diameter and flesh thickness rate. From quality indices, 4 common factors were extracted with 90.03% cumulative variance contribution rate and the explanatory indices were VC content, hardness, total soluble solids content, total sugar content, titratable acid content, sugar-acid ratio and solid-acid ratio. Based on the comprehensive analysis of these selected 6 economic trait indices and 7 flesh quality indices, 5 common factors were extracted with 87.35% cumulative variance contribution rate. According to the correlation among the indices and the principle of simplicity and ease of use and avoidance of overlapping information, 5 indices, including fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content, could be used as typical indices to evaluate the fruit quality of ‘Yangjiaocui’ melons. The comprehensive quality score of all materials were ranked depended on scores and variance contribution rate of the above 5 common factor and two-dimension ordination map. Finally, 10 materials were selected as high quality materials. 【Conclusion】 Fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content could be used as typical indices to evaluate fruit quality of ‘Yangjiaocui’ melons. Inbred lines 25, 24, 22, 21, 8, 1, 17, 18, 20 and 23 were high quality materials.  相似文献   
4.
为了筛选耐镉性较好的水稻品种,本研究利用气相色谱质谱联用仪,对24份不同耐镉程度的水稻品种进行了代谢物的定性与定量分析,通过主成分分析(PCA)和偏最小二乘判别分析(PLS-DA)等多元统计分析方法筛选出水稻耐镉差异性代谢物。结果表明:24份水稻种子共检测出59种主要代谢产物,有机酸类物质可将不同耐镉水平的水稻区分开;同时结合PLS-DA与T检验筛选后得出4种差异代谢物(VIP>1,p<0.05),其中9,12-亚油酸主要存在于低耐品种,而丙二酸、扁桃酸和D-甘露醇主要存在于高耐品种中。说明有机酸类物质与水稻耐镉性相关,可作为区分水稻种子耐镉差异的标志代谢物。  相似文献   
5.
[目的/意义]开展面向数字人文的古籍触发动词识别及分类研究,对于古籍文本的深层次挖掘和内容揭示具有重大的意义。本文利用深度学习分类算法,探索依据古籍触发词进行事件句文本多元分类的自动化方法。[方法/过程]在构建了典籍事件触发词分类体系和触发词典的基础上,选取4个不同类别的事件句文本作为实验数据,利用Onehot和Tokenizer对类别标签和句子文本进行分别编码后,输入Bi-LSTM模型中训练分类器,并通过调整参数设置了对比实验,采取通用的评价指标分析了分类器的性能。[结果/结论]经过多次训练和调整之后得到的分类器,在测试集的评估中精确度达到了0.95,证明基于深度学习的实验方法和构建的触发词数据集能够有效的帮助我们实现古籍事件句文本的自动化多元分类。  相似文献   
6.
A whole life‐cycle bioenergetic model based on the dynamic energy budget (DEB) theory was proposed for the three‐spined stickleback (Gasterosteus aculeatus). To develop this model, experiments on growth and reproduction were performed: adult and juvenile growth, size at first reproduction and amount of eggs spawned by females were monitored under different feeding levels and temperatures. The DEB parameters were estimated, using Bayesian statistics, based on the data produced during these experiments and on other data found in the literature. The model fitted accurately the different data used for the calibration process and, in addition, predicted accurately the data sets used to assess its predictability. Our bioenergetic model of the whole life cycle of the three‐spined stickleback accounting for environmental variations could contribute in many ways to improved ecological assessment: supporting change of scale from individual to populations; developing new biomarkers of exposure and effect; analysing ecotoxicity tests with biology‐based models.  相似文献   
7.
目前我国土地资源面临着严重的盐碱退化问题。以上海市崇明岛东滩盐碱土为研究对象,基于野外实地调查土壤盐分数据以及Landsat遥感影像数据计算获取的各波段反射率、盐分指数(salinity index,SI)、盐分指数1(salinity index 1,SI1)、归一化差分植被指数(normalized difference vegetation index,NDVI)、冠层盐分响应指数(canopy response salinity index,CRSI)和陆地表面水分指数(land surface water index,LSWI),采用多元样条自回归模型(multivariate adaptive regression splines,MARS)与偏最小二乘回归方法(partial least squares regression,PLSR)分别建立土壤盐分的回归模型,并对区域盐碱土的空间格局进行探究。结果表明:(1)滨海土壤盐分在近红外波段有明显的吸收作用,与近红外波段、短波红外波段和NDVI相关系数较高;(2)MARS模型较PLSR模型对于样点土壤盐分反演有更好的效果(R2分别为0.74和0.70);(3)崇明东滩滨海土壤盐分在空间上具有较高的异质性,水体附近和滩涂土壤盐分较高,林地和农田土壤盐分较低。该结果为滨海地区区域尺度上的土壤盐碱化监测提供范例,为滨海土壤盐渍化的治理及岛屿的生态建设提供参考依据。  相似文献   
8.
南岭泡金山矿产集采区土壤重金属空间分布及风险评价   总被引:5,自引:2,他引:3  
为探究典型多金属矿产集中开采区土壤重金属分布情况及其潜在风险,以南岭泡金山地区即湘南桥条江小流域矿采区为研究区,采集352个表层土壤样品,对Cr、Cd、Pb、Zn、Cu、Ni和As这7种重金属元素进行测试分析,综合运用数统和地统方法分析研究区整体及不同影响因素下土壤重金属的空间分布特征,并对其进行风险评价。结果表明,研究区表层土壤重金属均受到了不同程度的污染,矿区及其下游沿河地区污染严重,空间变异程度略高,复合污染、点源污染情况突出。土壤重金属含量基本随pH及有机质含量升高而升高;不同土地利用方式下土壤Cr、Ni、Cd含量变化不明显,草地、林地中Pb、Zn、Cu、As含量较高;不同地质背景条件下土壤重金属含量在成矿母岩(花岗岩体)、含矿围岩(D_2s+h)及矿区中下游干流一级阶地(Qx~Ⅰ)含量较高。研究区Cd、Pb、As单元素潜在生态风险水平较高,整体处于低-中等潜在生态风险水平,但矿区及其周边、下游沿河地区潜在生态风险为高或极高等级,可能会对北江流域产生一定影响,应该引起警惕予以重视。  相似文献   
9.
冷春晖  张露  易敏  孙世武  蒋祥英  赖猛 《核农学报》2020,34(7):1598-1605
为研究湿地松生长及树冠性状与产脂量之间的遗传相关关系及其对产脂量的控制途径,以赣北、赣中和赣南等多种典型立地条件下的28年生湿地松家系试验林为研究对象,对112个湿地松家系进行产脂量、生长及树冠性状全林调查,并对测定数据进行分析。结果表明,除枝下高外,产脂量与生长及树冠性状均呈显著或极显著遗传正相关关系,遗传相关系数排名前四的性状分别为胸径(R=0.93)、树冠表面积(R=0.83)、冠长(R=0.78)和冠幅(R=0.73);通径分析中,胸径、树高、树冠表面积和冠幅通过直接和间接作用成为影响产脂量的主导因素,其决定系数贡献率分别为0.557、0.507、0.424和0.240;产脂量与生长、树冠性状的线性回归方程为:y=-0.255+0.040x(DBH)+0.004x(HGT)+0.006x(CSA)+0.036x(CW)(F=955.907**, R2=0.559),模型的预估精度为99.64%。本试验结果明确了湿地松生长及树冠性状与产脂量之间的关系,其中,树高、胸径、冠幅和树冠表面积对产脂量影响较大;建立的产脂量多元回归模型具有一定的现实意义,实现了对树高、胸径和树冠表面积等性状的快速测定预估产脂量,为湿地松产脂量的科学、准确与高效预测提供了依据。  相似文献   
10.
Phyllostachys praecox is a bamboo species cultivated for edible shoots under intensive management. However, the potential pollution risk of heavy metals in bamboo soils is not clear under the intensive management for a long term. The objective of this study was to evaluate the effect of cultivation time on soil heavy metal accumulation and bioavailability in bamboo stands subjected to intensive management. Soil samples were collected from a chronosequence of bamboo stands which had been cultivated for 0, 1, 2, 4, 8, and 10 years in Lin''an, Zhejiang Province of China. Eight heavy metals (Cu, Zn, Pb, Ni, Cr, Cd, As, and Hg) present in the soil were selected, and their potential pollution risk was evaluated by chemical speciation analysis. Possible heavy metal sources were explored using multivariate and cluster analysis. Our results showed that Zn, Cu, Hg, and Cd contents in the soil increased with the cultivation time, while Ni, Cr, Pb, and As levels were similar among all stands. Furthermore, the bioavailabilities of all analyzed heavy metals increased with the cultivation time. Multivariate and cluster analysis showed that sources of Ni, Cr, Pb, and As were likely lithogenic in origin, whereas input of Zn, Cu, Hg, and Cd was mainly due to cultivation practices. Current bamboo management strategies raised the potential risks of heavy metal pollution in bamboo shoots in the long term. Soil acidification in P. praecox stands induced by intensive cultivation should be controlled since it stimulated and improved the bioavailability of heavy metals. Appropriate management strategies should thus be adopted to ensure safe and sustainable production of bamboo shoots.  相似文献   
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