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914.
对EPOR、MYPN 2个候选基因进行SNPs检测,并与肉质性状的关联分析,以期为分子育种提供依据。采用PCR-SSCP及PCR-RFLP方法对目的基因片段进行SNPs检测,结果显示,在研究群体内,EPOR基因不存在SNP,而MYPN基因存在2个SNP。用SAS软件对MYPN基因的2个SNP位点与部分肉质、胴体性状进行关联分析,结果表明,在本试验群体中,SNP1对背膘厚、导电性、眼肌面积和肌内脂肪的影响都达到了显著水平(P<0.05);SNP2对其中的背膘厚和肌内脂肪含量影响达到了显著水平(P<0.05);另外性别、品种对部分性状也有较大影响(P<0.05)。结合本研究结果和其它相关研究结果,可以推断MYPN基因可能是影响肉质、胴体性状的主效基因或与控制这些性状的主效基因连锁,可以作为肉质、胴体性状的候选基因。 相似文献
915.
基于SRTM-DEM和TM的流动沙丘提取方法研究 总被引:1,自引:0,他引:1
以塔克拉玛干沙漠的流动沙丘地貌为例,进行数字地貌形态提取方法研究。首先,利用高精度Srtm-DEM数据派生出坡度和起伏度两个地形因子数据,并参考坡度和起伏度的分类指标,实现沙地和沙丘边界线的自动提取,将风成地貌按照形态特征区分出沙地和沙丘两种地貌类型。其次,利用数学分析方法,根据斑块指数值的大小初步确定复合流动沙丘的类型。最后,基于高空间分辨率的遥感影像的色调、纹理、结构等特征,建立典型流动沙丘地貌特征的遥感影像特征图谱,依据遥感图谱进一步确定复合流动沙丘的类型,实现典型复合流动沙丘地貌形态和成因特征的计算机智能化提取方法。研究结果表明:该方法目前可以实现流动沙丘中的复合型链垄状沙丘、复合型沙垄、穹状沙丘和蜂窝状沙丘的智能化提取。 相似文献
916.
水稻杂种后代籽粒直链淀粉含量选择与品质和产量性状的关系 总被引:3,自引:0,他引:3
选用4个稻米直链淀粉含量有显著差异的粳稻品种配制两个杂交组合(系选1号×通769和东农423×藤系180),研究其杂交后代籽粒直链淀粉含量选择对品质和产量性状的影响。结果表明,籽粒直链淀粉含量选择对杂种后代蒸煮食味品质和产量相关性状有不同程度的影响,其影响程度因杂交组合及性状不同而异;在蒸煮食味品质性状中,淀粉黏滞性谱的崩解值和消减值受直链淀粉含量选择的影响较大,而在产量相关性状中抽穗期、单株有效穗数、结实率、单株粒重等受直链淀粉含量选择的影响相对较大;通过直链淀粉含量的连续定向选择可以从杂种后代中分出直链淀粉含量不同的后代,粳稻杂种后代低直链淀粉含量的定向选择效果优于高直链淀粉含量的选择效果,更容易得到超低亲的变异类型;直链淀粉含量的选择对杂种后代产量性状的影响较复杂,存在有利或不利的影响,低直链淀粉含量的选择将会导致单株粒重的下降。 相似文献
917.
水稻苗期盐胁迫下叶绿素荧光参数的QTL分析 总被引:2,自引:0,他引:2
应用247个株系组成的珍汕97B/密阳46重组自交系群体及其相应的含250个分子标记的高密度分子遗传图谱,通过复合区间作图法,对苗期水培和盐胁迫条件下水稻叶片叶绿素荧光参数进行了数量性状座位(QTL)分析。检测到控制水稻叶片叶绿素荧光参数(Fo、Fm和ΦPSⅡ)的7个主效应QTL,分布在水稻的第1、4、5和11染色体上,贡献率为598%~10.74%。其中,控制水培条件下Fm的QTL与控制盐胁迫下Fo的QTL均位于第5染色体的CDO82-RG413标记区间,说明此区间的QTL具有多效性,可同时影响Fm、Fo两个叶绿素荧光参数。 相似文献
918.
In a 2‐year field experiment, morphological development and measures of the nutritive value of herbage for livestock during primary growth in Meadow foxtail, Tall oatgrass, Cocksfoot, Perennial ryegrass and Yorkshire fog were investigated. All measured variables were affected significantly by both species and sampling date, and their interaction (P < 0·001), in the period of primary growth. Changes with time in mean stage weight for Meadow foxtail and Cocksfoot were different from the other species due to their indeterminate growth habits. Mean stage weight of Tall oatgrass and Yorkshire fog increased more rapidly than that of Perennial ryegrass with time. Changes in mean stage weight with time were described by linear, parabolic and sigmoid relationships. Crude protein (CP) concentration of herbage was higher for Cocksfoot and Meadow foxtail than for Perennial ryegrass. A parabolic relationship of CP concentration with time was typical for all the species. Concentrations of neutral‐detergent fibre (NDF) and acid‐detergent fibre (ADF) in herbage of the species differed most during the mid‐period of primary growth. Their increases with time showed curvilinear (sigmoid and parabolic) relationships. Perennial ryegrass had lower concentrations of both NDF and ADF in herbage than the other species. Differences between the in vitro dry matter (DM) digestibility among the grasses increased in mid‐ and late periods of primary growth. Perennial ryegrass had higher values for in vitro DM digestibility but the difference from other species was small in the early period of primary growth and from cocksfoot in the late period of primary growth. In vitro DM digestibility showed, in most cases, a sigmoid and, in others, a linear decrease with time. Principal component analysis showed that perennial ryegrass and meadow foxtail were the most distinctive of the species in characteristics relating to morphological development and the nutritive value of herbage to livestock. 相似文献
919.
J.E. Cairns O.S. Namuco R.Torres F.A. Simborio B. Courtois G.A. Aquino D.E. Johnson 《Field Crops Research》2009,113(3):207-217
Early vigour is an important characteristic for direct-seeded rice systems. The genetic control of early vigour was studied using a population of 129 backcross lines derived from a cross between Vandana, an improved indica, and Moroberekan, a traditional japonica. Screening was conducted under controlled conditions in greenhouse and field conditions, and indicators of early vigour, including shoot length, shoot biomass, leaf area, number of roots, root biomass, partitioning coefficients, and growth rates, were measured. Phenotypic correlations suggested that traits that were related and combined could be used to define early vigour. Broad-sense heritability ranged from moderate to high. Many regions were identified containing more than one QTL, suggesting that these traits were controlled by pleiotropic and/or closely linked QTLs. Many QTLs were specific to one environment but G × E interaction analysis showed that the main effects of the environment were large. Differences in temperature between experiments resulted in large differences in seedling age when expressed in thermal time. Different genes (QTLs) may be expected to control growth at different time intervals and thus may partly explain the limited agreement between experiments. However, several regions showed co-location of QTLs from more than one experiment. Comparisons with published studies revealed that these regions were previously identified in different genetic backgrounds and could potentially be used as introgression targets in a marker-assisted breeding program to improve germplasm for direct-seeded environments. 相似文献
920.
In water-efficient rice production, grain yield is often constrained by panicle size. The objective of this study was to genetically dissect the response of panicle morphology to irrigation regimes in aerobic rice culture. We grew ‘Akihikari’ (a lowland japonica cultivar) × ‘IRAT109’ (an upland japonica cultivar) backcross inbred lines in aerobic soils with full or limited irrigation for 2 years, and examined 4 panicle traits—number of florets per panicle (FPP), number of primary branches per panicle (BPP), number of florets per primary branch (FPB), and frequency of pre-flowering floret abortion (%FA)—and grain yield. QTLs for BPP were detected in both the irrigation regimes but QTLs for FPB and %FA were detected mostly only in either of the irrigation regimes. The QTL for FPP on chromosome 2 (RM3421–RM213) coincided with that for yield under full irrigation, showing that this QTL is related to sink capacity and yield potential in aerobic rice culture. On the other hand, the QTL for FPB on chromosome 1 (RM3148–RM243) coincided with that for yield under limited irrigation, when water deficit was moderate. The QTL for root axis length at vegetative stage, previously identified in the same mapping population, was located near this region. This study unravelled the complicated genetic control on panicle morphology in aerobic rice culture, and suggested the positive roles of the dehydration avoidance mechanism by vigorous root growth on panicle size and yield under dry soil conditions. 相似文献