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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LOX16和LOX18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LOX16和LOX18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.
Utilizing a DUALEM‐421 and inversion modelling to map baseline soil salinity along toposequences in the Hunter Valley Wine district
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In the oldest commercial wine district of Australia, the Hunter Valley, there is the threat of soil salinization because marine sediments underlie the area. To understand the risk requires information about the spatial distribution of soil properties. Electromagnetic (EM) induction instruments have been used to identify and map the spatial variation of average soil salinity to a certain depth. However, soils vary with depth dependent on soil forming factors. We collected data from a single‐frequency and multiple‐coil DUALEM‐421 along a toposequence. We inverted this data using EM4Soil software and evaluated the resultant 2‐dimensional model of true electrical conductivity (σ – mS/m) with depth against electrical conductivity of saturated soil pastes (ECp – dS/m). Using a fitted linear regression (LR) model calibration approach and by varying the forward model (cumulative function‐CF and full solution‐FS), inversion algorithm (S1 and S2), damping factor (λ) and number of arrays, we determined a suitable electromagnetic conductivity image (EMCI), which was optimal (R2 = 0.82) when using the full solution, S2, λ = 3.6 and all six coil arrays. We conducted an uncertainty analysis of the LR model used to estimate the electrical conductivity of the saturated soil‐paste extract (ECe – dS/m). Our interpretation based on estimates of ECe suggests the approach can identify differences in salinity, how these vary with parent material and how topography influences salt distribution. The results provide information leading to insights into how soil forming factors and agricultural practices influence salinity down a toposequence and how this can guide soil management practices. 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
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO
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7.
地膜覆盖对棉枯萎病发生的影响 总被引:1,自引:0,他引:1
地膜覆盖显著降低了棉花枯萎病的发病率与病情指数,极显著地提高了棉花的产量。 相似文献
8.
电导法测定林木种子活力的研究 总被引:4,自引:0,他引:4
本文研究了林木种子电导法测定条件和测定电导率或相对电导率,通过回归分析建立电导率或相对电导率与种子活力指数的相关方程,找出了电导法测定林木种子活力的方法。 相似文献
9.
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
10.