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1.
Fourteen varieties of rice from Taiwan, including five Indica, five Japonica, and four waxy cultivars, were used in this study for the examination of fine structure and physicochemical properties of amylopectin. The results indicated that the amylopectin of Indica rice had lower molecular weight, lower average degree of polymerization (DP), and lower average chain number when compared to Japonica and waxy varieties. The shortest average DP was 6 glucose units for all 14 rice varieties. The average chain lengths (CL) of amylopectin were 18–22, 15–18, and 17–20 for Indica, Japonica, and waxy rice, respectively. Indica varieties with high amylose content had amylopectin that comprised a few extra long chains (DP >100). The CL distribution profiles of amylopectins for these 14 varieties could be divided into two factions: CL 10–15 and CL 40–44. Amylopectin of the Indica rice had a relatively high blue value and λmax, implying that a high proportion existed as long branches. The amylopectin of three Indica varieties with lower DP exhibited higher intrinsic viscosity, which might be attributed to the more elongated rod conformation of the few extra long chain amylopectins. The proportion of short chains with DP 6–9 glucose units seemed to influence the rate of the retrogradation of amylopectins. 相似文献
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水稻土镉污染与水稻镉含量相关性研究 总被引：1，自引：0，他引：1
采用盆栽试验的方法,考察了水稻土中重金属镉（Cd）的浓度对水稻生长及Cd富集的影响以及Cd在水稻植株的分布情况,并进一步研究了糙米（可食部位）对Cd的富集量与土壤中Cd总量的关系。结果表明,在各个浓度Cd胁迫下,根、茎叶、稻壳、糙米相比,2个品种水稻都是根累积的Cd含量要高于茎叶和稻壳、糙米,即根〉茎叶〉稻壳〉糙米;在水稻的茎叶细胞中,Cd主要分布在细胞壁,细胞可溶性成分,细胞器Cd的分布量较少,即细胞壁〉可溶性部分〉细胞器及膜部分;随Cd浓度增加,茎叶中的Cd积累量极显著增加,各细胞组分中的Cd含量均显著增加;根据国标GB 2762—2005对大米中Cd的限量标准（≤0.2 mg.kg^-1）,水稻土土壤总Cd临界值分别为2.0 mg.kg^-（1博优225）、3.1 mg.kg^-（1矮糯）。因此,在污染土壤上宜选种食用部位重金属积累低的水稻品种,以减少人类吸收重金属的风险。 相似文献
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亚优2号高产的温光生态特性及其应用 总被引：1，自引：1，他引：1
亚优2号属中熟中稻类型的籼粳亚种间杂交组合,感温性明显强于感光性.生育期对氮素的反应仅次于温度,日长因子影响最小,它们的直接通径系数依次为0.5209、-0.5756、0.3067.它在减数分裂期与抽穗开花期对低温较敏感,要求适宜温度比耐寒性较差的籼稻还显著偏高,而抗高温的能力却明显超过较耐高温的籼稻.抽穗开花期如光强减弱,则严重影响颖花育性,结实率显著下降.因此,该组合抽穗开花期高温强光有利灌浆结实. 相似文献
5.
不同生产条件下留茬高度对水稻秸秆可收集量的影响 总被引：9，自引：0，他引：9
研究水稻不同留茬高度下秸秆资源可收集量与还田量是开展水稻秸秆资源合理开发利用的基础。本文通过对江苏省境内推广的主栽水稻品种进行调查研究, 将秸秆从基部向上依次截成长度为5 cm、10 cm、5 cm、5 cm 和剩余部分5 段, 对穗部单独脱粒处理, 分别进行烘干称重, 在此基础上分析了品种类型、种植方式和产量水平对水稻秸秆资源产生量及不同留茬高度下的秸秆可收集量的影响。结果表明: 水稻秸秆量多少表现为粳型稻>籼型稻, 机插秧>人工栽插>直播>抛秧, 高产水平>低产水平的特征; 相同留茬高度下, 水稻秸秆可收集量占秸秆总量的比例在不同产量水平之间和不同品种类型之间差异不显著, 而在不同种植方式之间存在较大差异, 以抛秧稻的秸秆可收集比例最低。不同生产条件下, 水稻秸秆可收集比例随留茬高度改变而改变, 在低留茬条件下, 其变化幅度较小, 高留茬条件下, 变化幅度相应增大。在留茬5 cm 时, 其变幅为0.815~0.868; 在留茬15 cm 时, 变幅为0.668~0.732; 在留茬20 cm 时, 变幅为0.600~0.669; 在留茬25 cm 时,变幅为0.533~0.618。水稻秸秆产生量分别受品种类型、种植方式及产量水平的影响, 在留茬高度一致的条件下, 水稻秸秆可收集比例受种植方式的影响最大, 而产量水平与品种类型对其影响不显著。 相似文献
6.
不同类型水稻品种对稻田土壤基础供氮量的响应 总被引：3，自引：0，他引：3
选用常规粳稻、杂交粳稻、常规籼稻、杂交籼稻及两系杂交稻5种类型共7个水稻品种,在大田中不施氮条件下,研究了供试水稻材料对土壤基础供氮量利用的差异。结果表明:①籼稻的土壤基础供氮量平均比粳稻高25.6%;杂交籼稻比常规籼稻高19.5%,杂交粳稻比常规粳稻高32.5%。②土壤基础供氮量在植株器官中的分配比例以叶、茎鞘的变异幅度较大,而穗的变异幅度则较小;叶中氮的分配比例以粳稻最高,而杂交粳稻与常规粳稻间及杂交籼稻与常规籼稻之间无明显差异。③土壤氮素利用效率(NUEs)随着土壤基础肥力上升而提高,粳稻的NUEs提高幅度大于籼稻。土壤氮籽粒利用效率(Ng/Ns)以两系杂交籼稻最高,籼稻的Ng/Ns大于粳稻,杂交籼稻与常规籼稻及杂交粳稻与常规粳稻间Ng/Ns无明显差异。④100kg籽粒需氮量增加幅度也是粳稻高于籼稻。 相似文献
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Singh V Okadome H Toyoshima H Isobe S Ohtsubo K 《Journal of agricultural and food chemistry》2000,48(7):2639-2647
Three types of rices, namely, Thailand rice (Indica), Nipponbare (Japonica), and Himenomochi (Japonica waxy), in grain, flour, and starch forms have been studied for their thermal and physicochemical properties. In grain form, Indica was slender and Japonica rices were bold and thick. Indica had the highest protein and amylose equivalent. Protein contents in isolated starches varied from 0.2 to 0.9%. Cooked Indica grain was hardest and waxy rice was softest; stickiness was highest in Japonica rice. Glass transition temperature (T(g)) was highest in Indica rice flour (approximately 222 degrees C) and almost the same in Japonica rice flours. Melting point was highest for Japonica (approximately 264 degrees C) and almost the same for Japonica waxy and Indica rice flours. T(g) values of starches were almost the same in Indica and Japonica waxy (approximately 237 degrees C); defatting caused reduction in this property in all of the starches. Highest melting point was shown by Indica starch (approximately 276 degrees C) and was almost the same for the other two starches. Protein and fats play a critical role in glass transition and melting points of rice flours and their respective starches. Viscosities of the cooked pastes of flour and starch during cooking in an RVA instrument and their gel and other properties have been discussed. 相似文献
9.
Satoru Ishikawa 《Soil Science and Plant Nutrition》2020,66(1):28-33
ABSTRACT Cadmium (Cd) has an important impact on agriculture, as the excessive consumption of this element from contaminated food crops leads to toxicity in humans. Rice is the greatest source of dietary Cd intake in populations consuming rice as a staple food. Therefore, reducing the Cd concentration of rice grains for diminishing the potential risk of Cd for human health is a major challenge. This review summarizes the main achievements on Cd accumulation in rice by our research group. Using a positron-emitting tracer imaging system, we succeeded to visualize differences in real-time Cd dynamics from roots to panicles in rice varieties with different Cd accumulation abilities. Several loci or genes responsible for Cd accumulation in rice were found through quantitative trait loci (QTLs) analysis. Using the QTL qCdp7 responsible for efficiently extracting Cd from paddy soils, practical rice varieties for Cd-phytoextraction were developed by DNA marker-assisted breeding. A rice variety named ‘Koshihikari Kan No.1? carrying a mutant allele of OsNramp5 for reducing Cd concentration in rice grains was produced by mutant breeding with ion-beams, and breeding programs have been implemented to transfer this allele into many Japanese rice varieties by DNA marker-assisted breeding. Growing low-Cd varieties aerobically would be a feasible way to simultaneously reduce inorganic arsenic and Cd concentrations in rice grains. These results provide basis for reducing Cd concentration in rice through breeding new varieties. 相似文献
10.
杂交稻及其恢复系的强弱势粒对光合物质摄取能力的比较 总被引：6，自引：0，他引：6
本研究选用杂交稻三组合及相应恢复系作为供试材料 ,分田间试验及盆栽试验两部分。结果表明 ,杂交组合及其相应恢复系的籽粒对标记储藏物质及标记光合物质的吸收分别达到 50 %和 80 % ,杂交组合籽粒的吸收量高于相应的恢复系 ,但差异不大 ,说明在储藏物质与光合产物的运输方面 ,杂交组合比相应的恢复系之间无明显差别。但是 ,杂交组合与相应恢复系的强弱势粒对标记储藏物质与光合物质的摄取量之间存在明显差异 ,强势粒是弱势粒吸收量的数倍乃至数十倍 ,尤其是杂交组合的强势粒对标记光合产物的摄取能力远高于弱势粒。杂交稻及其恢复系在物质分配方面表现出强势粒对弱势粒的粒间顶端优势 ,杂交组合比相应恢复系的粒间顶端优势表现更为明显。强势粒对弱势粒物质摄取能力的优势 ,可能是杂交稻籽粒结实率低下的重要原因之一。 相似文献
11.
五氯酚钠（PCP-Na）作为典型的氯代有机污染物,结构稳定难以降解且具有生物积累性,因而对环境生态系统及人体健康具有潜在风险。然而目前典型农作物对PCP-Na的吸收迁移及代谢特征的研究还不足。本研究采用温室水培实验,研究了15种水稻品种对PCP-Na的吸收差异,进而明确水稻对其体内PCP-Na的代谢能力。结果表明,水培浓度显著影响水稻对PCP-Na的吸收行为,且在胁迫的1-2天内水稻根部的PCP-Na累积浓度达到最大值。粳稻、籼稻、杂交稻品种的根部累积浓度分别为399-603、199-315、186-271 mg/kg;茎叶累积浓度分别为6.3-10.8、2.1-8.3、2.5-3.2 mg/kg。扬粳687号（粳稻）、农香24号（籼稻）、泰两优217号（杂交稻）是PCP-Na耐受性最强的三大水稻品种。研究还发现,水稻本体对PCP-Na具有较强的降解能力,水稻根部的PCP-Na在14天内从355下降至2.6mg/kg,茎叶内的PCP-Na在11天内从14.6下降至0.1 mg/kg。本研究有助于理解水稻对PCP-Na的吸收累积特征和降解能力,同时对水稻的安全生产和耐性育种提供一定的依据。 相似文献
12.
Lianhe Zhang Weiming Shi Xiaochang Wang Xinbin Zhou 《Journal of plant nutrition》2013,36(9):1601-1618
The paper deals with the selenium (Se) accumulation of different genotypes of rice (Oryza sativa Japonica) seedlings at early growth stage and its correlation with the Se content in grains in 151 rice varieties. A field trial showed the Se content in brown rice to range from 29 μg/kg to 103 μg/kg. The results from hydroponic culture with representative varieties of high-, moderate- and low-Se content showed that total Se values for the high-Se genotypes were markedly higher than those of the low-Se varieties. This was true of Se content of the whole plant, Se content of shoots, biomass of shoots, and rate of Se accumulation in shoots. There were, however, no significant differences in values for total Se in roots, rate of accumulation in roots, and biomass of roots between high- and low-Se groups. Selenium content in brown rice was positively correlated with the total Se of the whole plant, shoot, and biomass of shoots. We concluded that the total Se transported from roots to shoots was more important than other factors in Se accumulation and content in brown rice. 相似文献
13.
The eight vitamin E isomers [α-, β-, γ-, and δ-tocopherols (T) and α-, β-, γ-, and δ-tocotrienols (T3)] and γ-oryzanol are known to possess diverse biological activities. This study examined the contents of these compounds and their distribution in 16 commercial rice varieties in Taiwan. Results showed that the order of vitamin E, total T, total T3, and γ-oryzanol contents was rice bran > brown rice > rice husk > polished rice. γ-T3 was the highest vitamin E isomer present in all rice samples, while β-T, β-T3, δ-T, and δ-T3 were present in trace amounts. The Japonica varieties contained a higher total T, total T3, and γ-oryzanol than the Indica varieties. They also have a higher level of α-T and α-T3 but a lower level of γ-T and γ-T3 than the Indica varieties. However, no obvious difference in total T, total T3, and γ-oryzanol content was noted between black- and red-colored rice varieties. 相似文献
14.
增硝营养对不同基因型水稻苗期氮素吸收同化的影响 总被引：21，自引：7，他引：21
利用控制条件下的溶液培养方法,研究了增硝营养(NH4+∶NO3-比例为100∶0和50∶50)对4种不同的基因型水稻(常规籼稻、常规粳稻、杂交籼稻、杂交粳稻)苗期生长和氮素吸收同化的影响。结果表明,增NO3-营养可以增加水稻叶片的光合速率,促进水稻对氮素的吸收,提高氮素利用率,进而促进水稻生长;不同基因型水稻在增NO3-营养下氮积累量增幅不同主要是由于其生物量增幅不同,而整株氮素含量增幅差异不大;NO3-的存在可增强谷氨酰胺合成酶和硝酸还原酶的活力,促进水稻对NH4+和NO3-的同化利用,从而增加了氮素在植株地上部的积累同化;籼稻与粳稻相比,杂交粳稻与杂交籼稻相比,前者在氮素吸收利用上均表现出更为明显的优势。 相似文献
15.
随着水稻节水栽培技术越来越得到广泛的应用与推广以及水稻在淹水条件下根际氧化圈的存在,水稻的硝酸盐营养作用受到更大的关注。利用水培方法研究了4种具代表性的水稻基因型(常规籼稻、常规粳稻、杂交籼稻、杂交粳稻)在苗期(2 8d)的铵(NH 4 )吸收动力学特性以及硝(NO-3 )对NH 4 吸收动力学特征和叶片谷氨酰胺合成酶活性(GSA)的影响。结果表明:增NO-3 营养可以增加水稻对氮素的吸收,提高氮素利用率,进而促进水稻生长;不同基因型之间NH 4 吸收速率的差异为:杂交籼稻>常规籼稻>杂交粳稻>常规粳稻;NO-3 的存在促进了水稻对NH 4 的吸收,增加水稻吸收NH 4 的Vmax值(4个品种平均增加31 5 % ) ,而对其Km 值影响不大(4个品种平均增加4 2 6 % ) ,说明NO-3 对NH 4 吸收的影响主要在于影响NH 4 载体的运转速率而非吸收位点与NH 4 之间的亲和性;增NO-3 营养可以增加叶片谷氨酰胺合成酶(GS)的活性,提高水稻同化NH 4 的能力 相似文献
16.
Masako Okoshi Tomotaro Nishikawa Hiromori Akagi Tatsuhito Fujimura 《Genetic Resources and Crop Evolution》2018,65(3):713-726
Asian rice (Oryza sativa L.) is widely cultivated in Asia, where it has been classified into Indica and Japonica Group, the latter is further classified into Tropical and Temperate Japonica Subgroup. O. rufipogon is believed to be the closest ancestor to O. sativa, but it remains unclear whether the two groups arose from a single ancestor or different ancestors. Therefore, here, we investigated the matrilineal ancestors of O. sativa using markers for organelle (chloroplast and mitochondrial) genomes, and 119 O. sativa landraces, 10 O. glaberrima Steud., 115 O. rufipogon Griff. from Asia, and 39 accessions from other wild rice species with AA genomes. We screened 18 organelle markers developed based on polymorphic loci in the organelle genomes. In addition, we used the open reading frame 100 of a chloroplast marker. The results indicated that O. rufipogon first differentiated into two lineages and then further differentiated into Indica and Japonica Group, respectively. Accessions of O. rufipogon (R-1f and R-2d types) from Myanmar appear to be the closest ancestors of Tropical Japonica Subgroup and Indica Group, respectively. Therefore, these wild strains may have made a strong contribution to the domestication of rice landraces in Myanmar. 相似文献
17.
Genetic diversity and origin of Japonica- and Indica-like rice biotypes of weedy rice in the Guangdong and Liaoning provinces of China 总被引：1，自引：0，他引：1
Lianju Zhang Weimin Dai Chuan Wu Xiaoling Song Sheng Qiang 《Genetic Resources and Crop Evolution》2012,59(3):399-410
Weedy rice has been becoming a notorious weed in the paddy field of China in recent decades due to its increasing damage to
rice yield and rice quality. In this study, a microsatellite technique with 21 pairs of SSR markers was utilized to estimate
the genetic structure of two biotypes of weedy rice with Japonica and Indica rice characteristics, collected from Liaoning
and Guangdong provinces, respectively. The genetic diversity of the weedy rice in the two provinces was relatively low (Liaoning
h = 0.086; Guangdong h = 0.160), and distinctly large genetic differences existed between these two provinces (Gcs = 0.623). The genetic diversity was found primarily within populations, and genetic differentiation was relatively low within
the same province. Both cluster analysis (UPGMA) and principle component analysis (PCA) showed that weedy rice had a closer
relationship with the cultivated rice collected from the sample field than with other cultivated rice and common wild rice
varieties in China. Thus, the results of this study on samples from the Liaoning and Guangdong provinces in China support
the de-domestication hypothesis that weedy rice most probably originated from local cultivated rice. 相似文献
18.
辐照改良水稻淀粉特性的研究 总被引：8，自引：0，他引：8
以相似AAC的不同类型水稻 (籼稻、粳稻和杂交稻 )和不同AAC早籼稻品种为材料 ,研究了辐照对淀粉粘滞性、理化品质和淀粉颗粒的影响。研究表明 ,最高粘度 (PKV)、热浆粘度 (HPV)、冷胶粘度 (CPV)、消减值 (SBV)和回复值 (CSV)等 5个RVA谱特征参数随剂量增加均显著下降。辐照明显降低了低AAC品种、糯稻和中等AAC品种的AAC ,但对高AAC品种的AAC影响不显著。辐照对碱消值 (ASV)无影响 ,但最高粘度时间 (PKT)随剂量增加而下降。胶稠度尤其是高AAC的胶稠度 (GC)随剂量增加明显提高。胚乳内淀粉颗粒经辐照处理也有所变形。结果表明 ,辐照可提高稻米食用和蒸煮品质。 相似文献
19.
Stanislav Kuzel Václav Nýdl Ladislav Kolár Richard Tichý 《Water, air, and soil pollution》1994,78(1-2):51-59
Distribution of cadmium, pH KCl , and organic carbon content in the soil over a 29-ha field was evaluated. Cadmium concentrations were found mostly within the interval 0.17–1.27 ppm, with increasing trend towards one edge of the field. Cadmium concentrations were correlated with pH and organic carbon content. A one-hectare section of the original area was selected to analyze spatial variability of cadmium, pH and organic carbon content using geostatistical techniques. Cadmium concentrations were found to be spatially dependent and anisotropic, whereas pH levels did not reveal space dependence. Similar spatial behaviour of cadmium and organic carbon was observed. Linear correlation analysis at the one-hectare section revealed strong correlation between organic carbon and Cd, whereas no coincidence between Cd and pH was found. Extensive application of a cadmium-contaminated sludge in the past is suggested as a possible cause of this phenomenon. 相似文献
20.
Kishine M Suzuki K Nakamura S Ohtsubo K 《Journal of agricultural and food chemistry》2008,56(12):4605-4610
NERICA are interspecific rice varieties from crossing between the high-yielding Asian rice ( Oryza sativa spp. Japonica) with locally adapted African rice ( Oryza glaberrima). In this study, we analyzed grain qualities of 7 NERICA varieties (NERICA 1 to 7) and genetic derivation of quality-related genes. Quality analyses of NERICA grains showed that 7 NERICA varieties were clearly classified into two groups based on the difference of amylose content, and the difference influenced the pasting and physical properties of grains. Genetic analysis of the gene encoding granule-bound starch synthase I (GBSSI), which is known as a key enzyme on amylose synthesis in rice grain, revealed that varieties with higher amylose content ( approximately 29%) have the gene derived from O. glaberrima parent, and group 2 with lower amylose content ( approximately 22%) have the gene from O. sativa parent. These results indicated that the difference in amylose content as well as grain properties among 7 NERICA varieties is mainly determined by the genetic derivation of GBSSI. Further genetic analysis of starch synthesis-related genes suggested that the genetic derivation of SSIIa also influences the chain length of amylopectin in 7 NERICA varieties. 相似文献