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Characterization of waxy grain sorghum lines in relation to granule-bound starch synthase 总被引:4,自引:0,他引:4
The waxy phenotype, associated with endosperm containing little or no amylose, has been recognized in sorghum (Sorghum bicolor L. Moench) since 1933. Although variants of the waxy gene are well characterized in other cereals, the waxy trait has been
assumed to be controlled by a single allele, wx, in sorghum. Recent improvements in technologies encourage re-examination of the waxy sorghums. The objectives of this research
were therefore to identify and characterize sorghum lines with differing waxy alleles and to describe the actions of those
alleles in crosses. Grain of eight waxy sorghum lines (BTxARG1, BTx630, Tx2907, B.9307, 94C274, 94C278, 94C289, 94C369), three
wild-type checks (BWheatland, RTx430, BN122), and F2 families from crosses among a subset of these lines were evaluated for presence or absence of granule-bound starch synthase
(GBSS), the gene product of the wx locus, and wild-type vs. waxy endosperm. The F2 segregation ratios were tested for fit to a 3:1 ratio using Chi-square analyses. Two distinctly different naturally occurring
waxy alleles were identified: One with no GBSS (GBSS−), and one with apparently inactive GBSS present (GBSS+). We propose
that the waxy allele with no GBSS be designated wxa, and that waxy allele with apparently inactive GBSS present be designated wxb. These two alleles are located in close proximity on the waxy locus. The wxb allele is dominant to the wxa allele in terms of GBSS production, and both are recessive to the wild-type Wx in terms of amylose content.
The U.S. Government's right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
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本试验旨在研究饲粮直链/支链淀粉和淀粉酶对肉鸡生长性能和营养物质表观消化率的影响。试验采用4×3双因子设计,选用1日龄爱拔益加(AA)肉仔鸡960只,随机分为12个组,每组5个重复,每个重复16羽肉鸡,饲粮直链/支链淀粉分别为0.11、0.23、0.35、0.47,淀粉酶的添加量分别为0、3000、6000U/kg。试验期为21d。试验测定了肉鸡生长性能和营养物质表观消化率。结果表明:1)直链/支链淀粉为0.23的饲粮组肉鸡的平均日增重显著提高(P<0.05),料重比以直链/支链淀粉为0.47的饲粮组最高(P<0.05),其他组间差异不显著(P>0.05);饲粮中添加6000U/kg淀粉酶显著降低肉鸡平均日增重(P<0.05),但对料重比影响不显著(P>0.05);二者的互作效应不显著(P>0.05)。2)能量、粗蛋白质、干物质、粗脂肪以及钙表观消化率以直链/支链淀粉为0.11的饲粮组最高(P<0.05),直链/支链淀粉为0.47的饲粮组最低(P<0.05);饲粮中添加淀粉酶对营养物质表观消化率影响不显著(P>0.05);二者的互作效应对营养物质表观消化率影响显著(P<0.05)。综上所述,饲喂直链/支链淀粉为0.23和淀粉酶添加量为3 000 U/kg的饲粮可提高肉鸡的生长性能。 相似文献
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Can Yang Jun He Bing Yu Daiwen Chen XiangBing Mao Jie Yu Yulong Yin 《Journal of animal physiology and animal nutrition》2019,103(2):644-652
Amylose plays important role in body health. It is controversial whether changing dietary amylose/amylopectin ratio (DAR) will improve meat quality in growing‐finishing pigs. A total of 48 Duroc × Landrace × Large White castrated male pigs (initial body weight 49.8 ± 2.8 kg) were randomly allotted to two treatments, and fed ad libitum either with a low DAR diet (LR, amylose/amylopectin: 12/88) or a high DAR diet (HR, amylose/amylopectin: 30/70) for 68 days. Feed intake was recorded every day, body weight was weighed at 46th and 68th day to calculate average daily gain (ADG), average daily feed intake (ADFI) and Feed:gain ratio. Blood was collected at ?30 min (fasting 12 hr), 60, 90, 120, 180 min postprandial at 64th day and then serum was obtained by centrifugation of blood at 1,500× g at 4°C. After pigs were slaughtered, samples such as longissimus dorsi, iliopsoas and semitendinosus were collected. Density, diameter and types of muscle fibres were analysed. Results showed that ADG, ADFI, Feed:Gain ratio, cross‐sectional area of longissimus dorsi muscle, backfat thickness, colour scores were not affected by DAR. Ingestion of LR diet increased the fasting glucose (p < 0.05) and insulin (p < 0.05) concentrations in serum. The drip loss and firmness were decreased significantly in LR vs. HR animals (p < 0.05). Densities of muscle fibre in longissimus dorsi, iliopsoas and semitendinosus were greater in LR pigs (p < 0.05). Moreover, ingestion of LR diet significantly increased myosin heavy chain (MyHC) IIa mRNA level and decreased MyHC IIb gene expression in longissimus dorsi muscle (LM) (p < 0.05). Therefore, intake of diet low in amylose/amylopectin ratio induces a better meat quality (lower drip loss and lower firmness), which could attribute to smaller myofibres, a shift to slower and/or more oxidative fibres. 相似文献
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为建立一种同时测定糜子中直链和支链淀粉含量的简便方法,充实糜子理化性质的相关研究,首先应用双波长比色法,结合糜子直链淀粉/支链淀粉—碘复合物的吸收光谱图,确定其测定波长与参比波长。并利用标准工作曲线,求出样品中直链/支链淀粉的含量。由全波长扫描图谱确定了糜子中直链淀粉测定波长与参比波长分别为613 nm与520 nm,支链淀粉的测定波长和参比波长分别为538 nm与700 nm。结果表明,直链淀粉与支链淀粉的浓度分别在0~0.15 mg/mL和0~0.125 mg/mL呈线性相关。实验室用此法对15份糜子种质中直链与支链淀粉的含量进行测定。通过精密度与回收率实验,测得直链与支链淀粉的6次的标准偏差分别为0.145与0.022,回收率范围85.3%~97.9%。试验结果均满足分析要求,所建立的方法具有简便、快速、准确等特点,可用于测定糜子中直链和支链淀粉的含量。可对糜子口感及品质进行评价,从而筛选出优良种质。 相似文献
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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
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高抗性淀粉粳稻新品系稻米淀粉链长分布与主要品质特征差异 总被引:5,自引:1,他引:4
【目的】通过对水稻抗性淀粉性状的遗传研究,为高抗性淀粉水稻资源创新与育种提供理论和实践依据。【方法】以抗性淀粉含量有显著差异的粳稻品系为材料,比较分析高低抗性淀粉粳稻品系类型间的支链淀粉链长分布、稻米RVA谱特性值、膳食纤维和直链淀粉含量等主要品质特性的差异及其相关性。【结果】高低抗性淀粉水稻品系间支链淀粉链长分布差异显著,高抗性淀粉水稻品系的支链淀粉中短链部分即聚合度为5~12所占的相对百分比率显著低于低抗性淀粉类型品系,而长链尤其是聚合度为13以上的长链比率明显高于低抗性淀粉类型品系。膳食纤维和直链淀粉含量,高抗性淀粉品系显著高于低抗性淀粉品系,最高黏度值、最终黏度值、热浆黏度值和崩解值等,高抗性淀粉品系均显著或极显著低于低抗性淀粉类型品系。抗性淀粉含量与支链淀粉短链聚合度(DP≤12)呈极显著负相关,但与支链淀粉的中长链聚合度(12<DP≤36)呈极显著正相关,与直链淀粉含量和膳食纤维含量呈极显著正相关。【结论】水稻中支链淀粉的链长分布、直链淀粉含量和稻米RVA谱特性值与稻米抗性淀粉含量关系密切,在育种实践中可作为育种选择指标之一。 相似文献
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