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1.
为了解中国不同麦区小麦种质资源籽粒脂肪氧化酶(lipoxygenase,LOX)活性相关基因TaLox-B1的差异和分布,利用小麦4B染色体上的功能标记LOX16LOX18对7个麦区的436份种质资源进行分子检测。结果表明:在供试材料中共检测到3种TaLox-B1基因等位变异类型,分别为TaLox-B1a(与高LOX活性相关)、TaLox-B1b(与低LOX活性相关)和杂合型,其频率分别为19.0%、70.4%和10.6%。小麦LOX活性基因不同变异类型在各生态区的分布存在明显差异:基因型TaLox-B1a在黄淮冬麦区、北部冬麦区和长江中下游冬麦区分布较多,其比例分别为21.1%、19.8%和17.6%;基因型TaLox-B1b在西南冬麦区和长江中下游冬麦区分布较多,比例分别为87.9%、72.5%;杂合型仅存在于北部冬麦区、黄淮冬麦区与长江中下游冬麦区,比例分别为14.2%、12.4%和9.8%。利用标记LOX16LOX18对53个自选高代品系进行分子检测,发现自选品系仅有TaLox-B1b与杂合型两种基因型,其中基因型TaLox-B1ab有32个,比例为60.4%。采用分子标记辅助选择,有利于快速鉴定小麦籽粒LOX活性,加速LOX的遗传改良和新品种选育。  相似文献   
2.
In an effort to extract additional data from farinograph experiments a model was developed to simulate the measurements and correlate the parameters of the model with results from baking tests. This additional information can be used in bakeries to predict the baking properties of the flours and adjust the recipes to maintain a constant product quality. For this eight different flours were characterized with a farinograph and 13 different results from baking experiments. An approach with five nonlinear differential equations was able to model the farinograph measurements very well (average R2 = 0.995 ± 0.005). While a stepwise multilinear regression only showed weak correlations in cross validation between a single parameter of the model and the baking volume (R2 = 0.745) and the volume yield (R2 = 0.796) respectively, the artificial neuronal network was more successful. For the baking weight (R2 = 0.926), the dough yield gross (R2 = 0.909) and net (R2 = 0.913) strong correlations were found. A good correlation for the baking volume (R2 = 0.853) was also determined, while the volume yield showed comparable results to the linear regression (R2 = 0.792).  相似文献   
3.
The saddle panels, directly in contact with the horse's back, are likely an important element to optimize the fitting of the saddle, the comfort of the horse, and subsequently, the pain management in dorsalgic horses. The aim of this study was to better understand the effect of the saddle panels on the horse's back, by evaluating a prototype saddle (comfort panels: CP) compared to a standard saddle (STD). The horse's back movements were measured using inertial measurement units (IMUs) fixed at the levels of thoracic vertebrae T6, T12, T16 (under the saddle) and lumbar vertebrae L2 and L5. The centers of mass (COMs) of the horse and the rider and limb's protraction-retraction angles, pressure between saddle and horse's back, and force on the stirrups were measured using respectively 2D motion capture, pressure mat and force sensors in the stirrup leather. Three horses were trotted at the rising trot (sitting: left diagonal-rider seated; standing: right diagonal-rider standing) by the same rider. To compare saddles, linear mixed-effects regression models were used. The estimated means (SE) were calculated. During sitting phase, pressure in the cranial and middle areas of the saddle significantly increased for CP compared to STD (+0.9 (0.2) kPa and +1.0 (0.1) kPa, respectively) whereas caudal pressure decreased (−1.8 (0.4) kPa). Concurrently, the range of motion of angles T12-T16 and T16-L2 under the saddle significantly increased (+1.8 (0.2)° and +2.3 (0.3)°, respectively). The results showed that modifications of the panels' shape not only affect the pressure distribution but also the kinematics of the thoracic and lumbar regions of the equine back.  相似文献   
4.
Phenolic acids are major components of cell walls in wheat and have important implications on human health as antioxidants with anti-tumor activity. Our objectives were to identify phenolic acid genes in wheat by single nucleotide polymorphisms (SNPs) detected within the coding sequences of candidate genes, and to identify chromosomal regions associated with single phenolic acids and total soluble phenolic compounds. A set of candidate genes involved in the biosynthesis of hydroxycinnamic acid derivatives were identified by comparative genomics. SNPs found in the coding sequences of six genes (PAL1, PAL2, C4H, C3H, COMT1 and COMT2) were used to determine their chromosomal location and accurate map position on two reference consensus linkage maps. The genome-wide association study (GWAS), based on genotyping a tetraploid wheat collection with 81,587 gene-associated SNPs, detected 22 quantitative trait loci (QTL) distributed on almost all durum wheat chromosomes. Two QTL for p-coumaric acid were coincident with the phenylalanine ammonia-lyase (PAL2) and p-coumarate 3-hydroxylase (C3H) genes on chromosome arms 2AL and 1AL, respectively. The availability of candidate gene-based markers can allow elucidating the mechanism of phenolic acids accumulation in wheat kernels and exploiting the genetic variability of phenolic acids content for the nutritional improvement of wheat end-products.  相似文献   
5.
Differences in gas exchange parameters i.e. carbon exchange rate (CER), transpiration (Tr), water vapor conductance (g) were investigated, under a controlled environment, in a semi-dwarf (SD) Triticum aestivum line, its tall (TL) near isoline and the Payne (PA) variety characterized by small leaves. The plants were maintained in: (a) optimal substrate moisture condition (CTR); (b) salinized by watering with a 0.12 m NaCl solution (SLT); (c) water stressed by withholding waterings during a period of six days (STR); (d) stressed and salinized during the same period and with the same saline solution (S + S). CER and Tr were negatively affected by the stresses; SLT and S + S treatments had a higher WUE compared to their respective controls CTR and STR.
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO2 concentration curves contributed to explaining the SD performance.  相似文献   
6.
采用质量—数量性状遗传的极大似然分析方法,对长穗小麦品系93(220)的主茎穗长进行了质量—数量遗传模型测验和主、微基因效应与变异估计。结果表明:长穗小麦新品系93(220)的主茎穗长为一典型的质量—数量性状,由一个主基因和若干微基因共同控制;一对隐性主基因控制穗长,附合加性——显性遗传模型,F1代表现为部分显性,隐性主基因增加主茎穗长的效应平均为1.47,微基因遗传效应为2.83cm,隐性主基因个体主茎穗长表现为长穗。  相似文献   
7.
胡萝卜黄色突变体的遗传及表现研究   总被引:1,自引:0,他引:1  
 从胡萝卜‘新黑田五寸’品种的高世代自交系中发现了能稳定遗传的黄色突变体。遗传分析证明该黄色突变性状为单基因隐性遗传, 绿色对黄色为完全显性。黄色突变体叶片中叶绿素含量仅为正常株的29.3% ~50.1% , 且黄色不受温度光照等环境的影响。黄色突变体( yelyel) 地上部和地下部的生长量明显少于正常株系( YELYEL ) , 但在等位基因杂合时( YELyel) 与正常株系的生长量、产量和营养品质无显著差异。  相似文献   
8.
人工接种试验结果表明,雪腐格氏霉(Gerlachia nivalis)引起的小麦成株期叶枯、鞘枯和穗腐,鞘枯使小麦穗粒重减少2.1%~27.1%,千粒重降低9.5%~16.9%;穗腐使小麦穗粒重减少9.6~33.9%,千粒重降低7.8%~17.9%;鞘枯—穗腐复合症状使穗粒重减少10.2%~55.2%,千粒重下降9.5%~14.8%;叶斑—鞘枯—穗腐使穗粒重减少11.7%~47.1%,千粒重下降12.1%~18.3%。  相似文献   
9.
加入世贸组织总体上对我国的反腐败斗争是有利的。但由于西方国家对我国进行外部渗透和影响的机会增多;我国经济、政治等体制改革的不彻底;入世初期的接轨工作难以到位;高智化、国际化、团伙化的犯罪特点;新一轮资产重组等原因,存在着腐败滋生蔓延的必然条件,新的腐败犯罪的高发期还可能出现。为此,我们要坚持依法治国,加强法律、法规建设,加快政治体制改革,强化办案职能,严肃查处各种腐败犯罪,加大对国有资产监管的力度,依法治权,依法行政,完善党内各项运行机制,从源头上预防和治理腐败;加强思想教育,提高党员干部素质,增强拒腐防变的能力,自觉抑制腐败;密切国际间的相互协调与合作,共同打击腐败。  相似文献   
10.
不同生态条件下小麦子粒中戊聚糖含量的研究   总被引:8,自引:0,他引:8  
采用统一供种,统一试验方案,对河南省有代表性的生态地点的8个小麦品种的戊聚糖含量、蛋白质含量,吉粒重和产量进行了分析,初步认为生态因素是影响小麦子粒戊聚糖含量,蛋白质含是,千粒重和产量的重要因素,品种遗传因素对小麦品种的影响有着不可忽视的作用。综合戊聚糖含量、蛋白质含量产量来看,以豫麦34号为最好。  相似文献   
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