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1.
Decrease of Waxy (Wx) Protein in Two Common Wheat Cultivars with Low Amylose Content 总被引：17，自引：0，他引：17
Two cultivars with a low amylose content, Kanto107 (K107) and K79, were discovered in Japanese common wheat (Triticum aestivum L.). The amount of Wx protein, identified as a single major starch granule-bound protein of about 61 kD by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), was greatly decreased in those two cultivars. Analysis of their Wx protein with a modified SDS-PAGE and two dimensional-PAGE showed that two of the three Wx proteins, produced by Wx-A1 and Wx-B1 loci, were not detected. It was thus concluded that only one locus, Wx-D1, was active in the two low amylose cultivars. These mutants were termed “partial waxy mutants” and considered to be very useful material for breeding waxy wheat. 相似文献
2.
以小麦品种藁城8901为母本,糯麦1号为父本,用“单粒传”法构建了一个含有8种Wx基因突变类型的重组自交系群体 (RIL) 。应用改良的SDS-PAGE方法对RIL-7的Wx基因突变类型进行检测,发现在228个株系中,正常类型的株系有34个,Wx-A1突变体为26个,Wx-B1突变体为32个,Wx-D1突变体30个,Wx-A1和Wx-B1位点同时突变的有28个,Wx-A1和Wx-D1位点同时突变的有20个,Wx-B1和Wx-D1位点同时突变的为28个,3个Wx基因位点均突变的为16个。卡方测验证明,3个Wx基因位点的突变符合孟德尔遗传规律,属于质量性状遗传。田间试验表明,8种类型之间在初花期、株高和穗粒数上无显著差异,但在穗长、每穗小穗数和千粒重上Wx-A1突变型显著低于其他7种类型,而7种类型间无显著差异。淀粉特性研究表明,不同Wx蛋白缺失显著影响直链淀粉含量、淀粉糊化特性和淀粉凝胶的质构剖面分析 (TPA) 特性。正常类型的直链淀粉含量最高(20.8%),糯麦的最低(1.1%)。糯麦淀粉的峰值黏度和稀澥值较高,但其低谷黏度、最终黏度和反弹值较低,与其他缺失类型间差异达5%显著水平。凝胶的TPA测试表明,随着直链淀粉含量的降低,凝胶的硬度、黏着性、弹性、胶着性和咀嚼性显著降低,而黏聚性和回复性显著升高。直链淀粉含量与糊化特性的低谷黏度、最终黏度、反弹值、峰值时间和糊化温度之间正相关达1%显著水平(r=0.892~0.965),与峰值黏度、稀澥值呈1%水平负相关( r=－0.892, r=－0.945);直链淀粉含量与凝胶TPA参数的黏聚性、回复性呈极显著负相关(r=－0.928, r=－0.829),与凝胶的硬度、黏着性、弹性、胶着性和咀嚼性呈极显著正相关( r=0.869~0.979)。 相似文献
3.
Development of a kompetitive allele‐specific PCR marker for selection of the mutated Wx‐D1d allele in wheat breeding 
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下载免费PDF全文 Wenjing Hu Yun Zhao Tongde Bie Derong Gao Datong Liu Ronglin Wu Xiaoming Cheng Shunhe Cheng Yong Zhang 《Plant Breeding》2017,136(4):460-466
Waxy (Wx) protein is a key enzyme for synthesis of amylose in endosperm. Amylose content in wheat grain influences the quality of end‐use products. Seven alleles have been described at the Wx‐D1 locus, but only two of them (Wx‐D1b, Wx‐D1e) were genotyped with codominant markers. The waxy wheat line K107Wx1 developed by treating ‘Kanto 107’ seeds with ethyl methanesulphonate carries the Wx‐D1d allele. However, no molecular basis supports this nomenclature. In the present study, DNA sequence analysis confirmed that a single nucleotide polymorphism in the sixth exon of Wx‐D1 changed tryptophan at position 301 into a termination codon. Based on this sequence variation, a PCR‐based KASP marker was developed to detect this point mutation using 68 BC8F1 plants and 297 BC8F2 lines derived from the cross ‘Ningmai 14’*9/K107Wx1. Combined with codominant markers for the Wx‐A1 and Wx‐B1 alleles, waxy and non‐waxy near‐isogenic lines were distinguished. The KASP marker was efficient in identifying the mutant allele and can be used to transfer waxiness to elite lines. 相似文献
4.
The waxy (Wx) gene encodes a granule-bound starch synthase (also called Wx protein) that is involved in synthesizing amylose in the starch grains of cereals, including common wheat (Triticum aestivum L.). Because amylose content affects the quality of food products made from wheat flour, Wx alleles affecting amylose content are of interest. Five wheat Wx alleles (Wx-A1c, -A1d, -A1e, -A1i and -A1j) that produce polymorphic Wx proteins on electrophoretic gels were investigated in terms of amylose content in starch and DNA sequences. Measurement and electrophoresis of gelled starch showed that apparent amylose contents of the genotypes were as follows: Wx-A1e, 2.9 % (= waxy phenotype) < -A1i, 8.0 % < -A1c, 16.8 % < -A1j, 22.6 % = level of wild type allele -A1a. DNA sequencing of the five alleles identified single nucleotide polymorphisms (SNPs) and insertion/deletion variations compared to Wx-A1a. A particular SNP causing amino acid changes in Wx-A1e and -A1c was identified as the factor responsible for decreased amylose. A SNP in Wx-A1d should cause an amino acid change and be responsible for an altered Wx-A1d protein. A transposable-like element of 376 bp present in the 3′ untranslated region (UTR) of Wx-A1i most likely lowered the levels of Wx protein and amylose through aberrant mRNA. The fifth allele, Wx-A1j, possessed four SNPs, two of which altered amino acids in the Wx-A1j protein and should cause polymorphism in the Wx protein. Based on the DNA sequences, functional markers for Wx-A1c, -A1d, -A1e and -A1i were developed. 相似文献
5.
Development of near-isogenic lines of wheat carrying different null Wx alleles and their starch properties 总被引：3，自引：0，他引：3
The granule-bound starch synthase (GBSS I) encoded by the Wxgenes, is involved in amylose synthesis. For analyses of mechanisms of amylose synthesis and associated starch properties
in hexaploid wheat, eight possible genotypes having different combinations of the three null alleles at the Wx loci with a common genetic background are a prerequisite. A near-isogenic population of doubled haploid (DH) lines was produced
from Chinese Spring × waxy Chinese Spring F1 plants using the wheat × maize method. The Wx protein phenotypes of the DH progeny were examined by sodium dodecyl sulphate-polyacrylamide
gel electrophoresis and found that the null alleles at each of the three Wx loci segregated in a Mendelian fashion. A field trial demonstrated no differences between the eight types for ear emergence
time, plant height and grain yield traits. Amylose content in the endosperm starch was highest in the wild type while lowest
in the waxy type having no Wx proteins. Comparison between single null types and double null types indicated that the amylose
synthesis capacity of Wx-A1a allele is the lowest. Pasting properties of starch are the highest in the waxy type, followed by the double null types. Consequently,
both peak viscosity and breakdown were negatively correlated with amylose content. The chain-length distribution analysis
of amylopectin structure revealed no clear difference among the eight types,suggesting that the reduced GBSS I activity due
to introgression of the null Wx alleles does not affect either the chain length or the degree of branching of amylopectin.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
To clarify the genetic mechanism which controls the variation in amylose content among nonwaxy landraces of foxtail millet,
the inheritance of different starch types in endosperm was examined by I2-KI staining. The level of starch granule bound protein in foxtail millet endosperm was also analyzed using SDS-PAGE. The
segregation for starch types in F2 and F3 seeds determined by I2-KI staining showed that there are three different alleles at the waxy (wx) locus. A major protein bound to starch granules
was detected in nonwaxy endosperm but it was absent in most of the waxy endosperm, suggesting that the protein is the Wx gene
product which is responsible for the synthesis of amylose in endosperm. The level of Wx protein proportionally corresponded
to the amylose content among nonwaxy landraces. This implies that two different Wx alleles regulate quantitative levels of
Wx protein. Landraces with the allele for low amylose content are from Taiwan, the Philippines, Indonesia and Thailand.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
两个直链淀粉含量不同的小麦品种籽粒淀粉合成酶活性与淀粉积累特征的比较 总被引：12，自引：0，他引：12
以均含有3个Waxy蛋白亚基的普通小麦品种济麦20（低直链淀粉含量）和鲁麦21（高直链淀粉含量）为材料，对灌浆期籽粒淀粉合成相关酶活性的变化及淀粉积累特征进行了研究，并分析了两者之间的关系。结果表明，蔗糖合成酶(SS)、腺苷二磷酸葡萄糖焦磷酸化酶(AGPP)、束缚态淀粉合成酶(GBSS)、可溶性淀粉合成酶(SSS)和淀粉分支酶(SBE)活性均呈单峰曲线变化。鲁麦21的上述酶活性均高于济麦20。相关分析表明，支链淀粉积累速率与SS、AGPP、SSS和SBE呈显著或极显著正相关；直链淀粉积累速率与SS、AGPP和GBSS呈极显著正相关。Logistic方程拟合淀粉积累过程发现，支、直链淀粉最终积累量的高低取决于积累启动时间的早晚和积累速率的高低，而积累持续期的调节作用较小。直链淀粉的积累速率除受GBSS活性影响外，还受SS和AGPP活性的影响，其中，GBSS活性的变化与2品种籽粒直链淀粉积累量的变化情况基本吻合。籽粒灌浆后期的GBSS活性对直链淀粉最终积累量的调节作用大于灌浆前期，说明对同时具有3个Waxy蛋白亚基的不同品种，Waxy蛋白亚基表达量(GBSS活性)的差异可能是导致品种间籽粒直链淀粉含量较大差异的一个关键原因。 相似文献
8.
The entire USDA‐ARS maintained collection of 650 accessions of proso millet (Panicum miliaceum L.) was evaluated for the presence of accessions with waxy (amylose‐free) endosperm starch. Six accessions, five of which derived from mainland China, were identified. Segregation ratios for waxy endosperm were evaluated in F2 and F3 populations derived from crosses between two waxy accessions, PI 436625 (Lung Shu 16) and PI 436626 (Lung Shu 18), and several wild‐type accessions. The waxy trait was found to be under the control of duplicate recessive alleles at two loci, herein designated wx‐1 and wx‐2. Wild‐type alleles at these loci were designated Wx‐1 and Wx‐2. Iodine‐binding revealed a mean grain‐starch amylose concentration of 3.5% in waxy lines and 25.3% in wild‐type proso. Expression of the granule‐bound starch synthase (waxy protein) in waxy lines was reduced to approximately one‐tenth that of wild‐type accessions. The waxy accessions identified now are available for the introgression of this trait into breeding lines adapted to the Great Plains of North America. 相似文献
9.
Summary The starch-granule bound proteins of common wheat (Triticum aestivum L.) and six related species were examined by SDS-polyacrylamide gel electrophoresis. They showed almost the same molecular weight, 61 kD. The amount of the starch-granule bound protein varied among Japanese wheat cultivars although the variation was not as wide as that for rice. The amount of this protein of Kanto 107 and Kanto 79 was about 40% of that of Norin 98. In addition, wheats with lower starch-granule bound protein also possessed lower amylose content. 相似文献
10.
西南糯玉米地方品种waxy基因序列多态性分析 总被引：7，自引：2，他引：5
为了解我国西南地区糯玉米和硬粒玉米waxy基因核苷酸多态性, 对23份中国西南玉米地方品种(16份糯玉米和7份硬粒玉米)、2份美洲糯玉米种质的waxy基因第9外显子至第14外显子之间核苷酸序列进行测定, 将所得序列与GenBank中的16份同源序列(来自小颖大刍草、繁茂大刍草和美洲地方栽培品种)进行序列比对。结果表明, 西南糯玉米、西南硬粒玉米和小颖大刍草分别具有14、19和40个多态性位点, 西南糯玉米waxy位点核苷酸多态性为西南硬粒玉米的30%, 是小颖大刍草的14%, Tajima’D检验仅在糯玉米群体D值显著, HKA检验表明waxy位点未受选择作用; 序列比对发现12份西南糯玉米第10外显子同一位置缺失15个核苷酸, 该位点恰为糖基转移酶结构域的起始位置。可见我国糯玉米通过较为独特的突变机制而形成, 在进化过程中经历了驯化瓶颈, 奠基者效应使西南糯玉米waxy位点核苷酸多态性大大降低, 从近缘物种中引入等位变异是改良玉米淀粉质量和产量的关键。 相似文献
11.
The Wx locus controls amylose synthesis in the cereal endosperm. Hexaploid wheat (Triticum aestivum L.) has the three Wx loci on chromosomes 7A ( Wx-A1), 4A (Wx-B1) and 7D (Wx-D1). To verify the effects of null alleles on reducing amylose content and determine the amylose synthesis capacity of each
Wx gene independently and accurately, we produced eight possible types of recombinant lines carrying different null alleles
at the Wx loci under the ‘Chinese Spring’ genetic background. Amylose content varied from 0% of the waxy ‘Chinese Spring’ to 25% of
the ‘Chinese Spring’ normal type. The reducing effect of the single null alleles was the largest in Wx-B1b, and there was no significant difference between Wx-A1b and Wx-D1b. More than 3% reductions in amylose content were detected in the double null types. The results of the double null lines
further demonstrated that for the capacity of amylose synthesis, Wx-B1a predominates and produces 21–22% amylose, followed by Wx-D1a (20–21%) and Wx-A1a (15–18%). These significant differences were partly correlated with variation in the amounts of the Wx proteins produced by different Wx genes. However, comparisons of the double null lines with the single null or normal lines indicated that amylose content
was not linearly proportional to the number of the Wx genes, suggesting that the Wx genes act in an epistatic manner.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
鲜食糯玉米采后糖代谢变化 总被引：1，自引：0，他引：1
【研究目的】了解鲜食糯玉米采后的糖代谢变化以及温度变化对糖代谢的影响。【方法】测定鲜食糯玉米采后的蔗糖、还原糖、直链淀粉、支链淀粉的含量变化。【结果】鲜食糯玉米采后的蔗糖、还原糖含量都有较大下降;采后第1d直链淀粉、支链淀粉和总淀粉的含量都达到峰值,之后直链淀粉变化不大,支链淀粉的含量略有下降,总淀粉含量呈增加趋势;与20℃贮藏温度对比,贮藏温度为0℃时蔗糖、还原糖含量、直链淀粉含量高,支链淀粉、总淀粉含量低。【结论】鲜食糯玉米采后可溶性糖向淀粉转化的合成代谢仍然占据主导地位,贮藏温度为0℃时能够延缓可溶性糖向淀粉,以及直链淀粉向支链淀粉的转化。 相似文献
13.
小麦Wx基因近等基因系的创制及其对直链淀粉含量、面条感官品质的影响 总被引：2，自引：0，他引：2
为明确不同Wx基因对小麦直链淀粉含量的影响以及筛选面条品质优异的基因型,以糯小麦品系Caiwx (aabbdd)为3个Wx基因隐性突变供体亲本,以扬麦01-2 (AABBDD)为轮回亲本,利用连续回交结合花粉碘染、STS标记和同工酶标记检测方法,创制了8种Wx基因纯合基因型的近等基因系,其基因型分别为AABBDD、AABBdd、AAbbDD、AAbbdd、aaBBDD、aaBBdd、aabbDD和aabbdd。利用这些基因型探讨了不同Wx基因对直链淀粉含量及面条感官品质的影响。结果表明,各系的直链淀粉含量为0.9%~24.8%,系间差异显著;糯小麦型(aabbdd)直链淀粉含量最低,双缺失型和单缺失型其次,双缺失型中aaBBdd型含量最高,单缺失型中AAbbDD型含量最低,表明Wx-B1对直链淀粉的合成作用最大。糯小麦型面条的色泽、表观、软硬度、黏性、韧性得分以及总分显著低于其他类型及轮回亲本扬麦01-2;单缺失型面条的色泽、表观得分、总分显著高于轮回亲本扬麦01-2,其中aaBBDD型面条品质表现突出,与市售优质面条粉“雪花粉”制作的面条得分相当,而其他7种基因型及轮回亲本扬麦01-2的面条评分均显著低于雪花粉。说明可以通过遗传操作Wx基因培育优质面条小麦品种。 相似文献
14.
旱作和灌溉条件下小麦籽粒淀粉粒粒度的分布特征 总被引：6，自引：0，他引：6
在灌溉和旱作2种栽培条件下, 以籽粒淀粉含量不同的小麦品种鲁麦21和德99-3为试验材料, 研究了籽粒淀粉粒的分布特征及基因型差异。结果表明, 与灌溉栽培相比, 旱作栽培条件下2个小麦品种籽粒B型淀粉粒(2.0~9.8 mm和<9.8 mm)的体积、表面积百分比显著增加, 而粒径>18.8 mm的A型淀粉粒的体积、表面积百分比明显减少。水分亏缺降低了2个品种的籽粒直链淀粉和总淀粉含量, 而增加了籽粒蛋白质含量、峰值黏度和最终黏度, 这表明旱作栽培有利于小麦籽粒品质的改善。相关分析表明, 2个品种籽粒的直链淀粉和总淀粉含量均与2.0~9.8 μm和<9.8 mm的淀粉粒体积百分比呈负相关, 与9.8~18.8 mm的淀粉粒体积百分比呈正相关, 籽粒蛋白质含量与2.0~9.8 mm和<9.8 mm的淀粉粒呈显著和极显著正相关, 而与9.8~18.8 mm的淀粉粒呈负相关。表明小淀粉粒(2.0~9.8 mm和<9.8 mm)的直链淀粉和总淀粉含量较低、蛋白质含量较高, 而大淀粉粒(9.8~18.8 mm和>9.8 mm)具有较高的直链淀粉和总淀粉含量。 相似文献
15.
为研究大麦籽粒支链淀粉、直链淀粉和β-葡聚糖积累特性,及淀粉各组分与β-葡聚糖的关系,以2个皮大麦、1个裸大麦和1个糯裸大麦为试验材料,测定花后7、14、21、28d淀粉各组分及β-葡聚糖含量。结果表明,甘啤6号淀粉各组分含量随灌浆推进均逐渐升高,在成熟期达到最大值;甘垦啤7号和甘垦6号均呈先升高后降低趋势,在花后21d有1个峰值。糯大麦C 2-1直链淀粉含量显著低于非糯大麦;支链淀粉含量显著高于非糯大麦,整个灌浆期呈先升高后降低趋势。β-葡聚糖含量均随灌浆时间延长逐渐升高,成熟期含量最高;整个灌浆期糯大麦C 2-1含量显著高于非糯大麦。相关分析表明,直链淀粉/支链淀粉比值与β-葡聚糖含量呈极显著负相关,可以将直链淀粉/支链淀粉比值作为高β-葡聚糖品种选育的一个指标。Logistic方程拟合发现,直链淀粉、β-葡聚糖最终积累量与积累起势与有效积累时间有关,支链淀粉最终积累量取决于最高积累速率和平均积累速率。 相似文献
16.
从由化学诱变剂甲基磺酸乙酯(ethylmethane sulfonate,EMS)处理的粳稻品种中花11突变体库中,筛选到一个可稳定遗传的胚胎和胚乳发育缺陷的突变体,命名为embryo and endosperm defective 1 (eed1)。eed1籽粒千粒重、颖果的粒长、粒宽、粒厚、萌发率、总淀粉、直链淀粉和贮藏蛋白系列指标较野生型均显著降低。eed1颖果严重皱缩,且胚乳呈粉质。利用扫描电镜观察发现,与中花11相比, eed1胚乳中淀粉粒排列疏松,多以单一、分散的淀粉粒存在,且呈近似球形。eed1胚胎结构异常,部分颖果未见有胚胎分化的痕迹。qRT-PCR发现, eed1胚乳中参与淀粉和贮藏蛋白合成的大部分基因表达下调。利用eed1与籼稻南京6号杂交得到的F2分离群体进行基因定位分析,将EED1定位于9号染色体长臂672kb的范围内,包含114个开放读码框。本研究为进一步解析EED1基因调控水稻胚胎和胚乳发育的机制奠定了基础。 相似文献
17.
无抗性选择标记转基因软米和糯稻新品系的选育及中间试验 总被引：1，自引：0，他引：1
直链淀粉含量是影响稻米品质的最重要因素之一。为培育直链淀粉含量较低的软米和糯稻新品系,在经共转化法获得的转反义Wx基因水稻自交后代中筛选获得国不含抗性选择标记基因的纯合体.对这些纯合转基因水稻的分析表明,其未成熟种子胚乳中Wx基因表达水平和成熟种子中Wx蛋白量较未转化对照有不同程度的降低。转基因水稻成熟种子中直链淀粉含量较未转化对照有不同程度的下降,2个转基因系降低至10%左右,相当于软米的直链淀粉含量,1个转基因系降到了2%以下,形成了糯稻新品系。转基因稻米中直链淀粉含量降低后,其胶稠度相应变软,而糊化温度未发生明显改变。田间试验结果表明,转基因水稻的大部分农艺性状与受体品种武香粳9号无显著差异。因此,本研究成功培育了无抗性选择标记且淀粉品质改良的转反义Wx基因水稻新品系。 相似文献
18.
Genetic variation for waxy proteins and starch properties in Italian wheat germplasm 总被引：15，自引：0，他引：15
Granule-bound starch synthase (GBSS) is the primary enzymeresponsible for the synthesis of amylose in amyloplasts of cereal endospermcells. In bread wheat there are three structural genes (Wx-A1, Wx-B1,and Wx-D1) encoding for isoforms of GBSS. The loss of one or moreGBSS isoforms results in the reduction (partial-waxy) or absence (waxy) of amylose in the starch. Waxy wheats may find application inthe production of modified food starch and their flour may be used toextend the shelf life of baked products. In order to breed high qualitywheats able to produce bread with delayed staling, the genetic variabilityfor the waxy trait in our germplasm has been investigated. Weanalysed 288 cultivars of bread wheat, 139 cultivars of durum wheat andabout 200 accessions from other Triticum species. Gel electrophoresisshowed 63 bread wheats deficient in the Wx-B1, one in the Wx-A1 and one in the Wx-D1 protein isoforms, as well as one Triticum dicoccum lacking the Wx-A1 isoform. None of the analysedTriticum monococcum, Triticum durum, Triticum speltaand Triticum timopheevi accessions showed mutations at the Wxloci. The wheat accessions with Wx mutations were evaluated with aRapid Visco Analyser (RVA) to investigate starch properties. All theanalysed cultivars showed Peak Viscosity and Final Viscosity different fromthe normal wheat. Other analyses to evaluate the rheological characteristicsof the partial-waxy genotypes are under way and a breedingprogramme to select new waxy wheat varieties is in progress 相似文献
19.
The non-transgenic manipulation of starch properties in common wheat (Triticum aestivum L.) generally implies combining mutant alleles of the particular gene copies in all three subgenomes (A, B and D). The redundancy
of the hexaploid wheat chromosome set substantially complicates the identification of recessive mutations and breeding. Nevertheless,
naturally occurring or induced genetic polymorphism has already been successfully exploited for the production of waxy (GBSSI-deficient)
and elevated amylose (SSIIa-deficient) wheats. However, in order to achieve the amylose content above 50% of wheat endosperm
starch, it may be necessary to inactivate the starch branching enzyme (SBEIIa) isoforms, as the RNAi repression results and
gene expression data strongly suggest. The identification of null SBEIIa alleles and their combination in a single genotype is therefore a promising approach to the production of non-transgenic
high-amylose wheat; however, wheat SBEIIa polymorphism has not been characterized as of yet. In order to develop an approach to SBEIIa mutation screening, we sequenced the SBEIIa central region (exons 9–12) from the three subgenomes of common wheat cv. Chinese Spring and the A genome of diploid einkorn
T. monococcum. The genome-specific primers were developed that amplify the exons downstream from intron 11 selectively from each homeologous
gene. Using a single-stranded DNA conformation polymorphism (SSCP) approach, we screened 60 wheat cultivars, landraces, and
rare species for naturally occurring SNPs in exons 12, 13 and 14 of the three SBEIIa homeologs. In total, 13 SNPs were discovered in the A and B wheat genomes. Two of these SNPs affect the amino acid sequences
of SBEIIa isoforms and may change the enzyme functional properties. The presence of restriction site polymorphism at SNP positions
enables their easy genotyping with CAPS assays. Our results indicate that the mining for naturally occurring sequence polymorphism
in starch biosynthesis genes of wheat can be successfully performed at the DNA level, providing the starting point for a search
for SBEIIa mutants at a larger scale. 相似文献
20.
为分析太湖地区地方特色糯稻品种稻米品质性状,为后续特色糯稻种质的开发和利用提供依据,以鸭血糯和苏御糯及对照品种红壳糯和白壳糯为材料,分析了稻米的基本理化品质和淀粉结构特性。结果表明,鸭血糯和苏御糯具有较高的蛋白质含量和表观直链淀粉含量;鸭血糯和苏御糯米粉和淀粉均表现出较低的黏滞性,通过淀粉粒扫描电镜分析发现较小的淀粉粒可能是导致鸭血糯和苏御糯米粉和淀粉黏滞性较低的重要原因;热力学特性分析结果表明,鸭血糯淀粉具有最高的糊化温度和热焓值并且较易发生回生,其次是苏御糯淀粉;晶体结构分析表明,4个糯稻淀粉均表现为典型的A类型晶体结构,但鸭血糯淀粉的长程有序程度和短程有序程度均最高,其次是苏御糯淀粉。 相似文献