水稻亚(品)种间淀粉粘滞特性杂交转移的初步研究

以早籼稻品种浙辐504为母本,分别与中籼IR64、爪哇稻Lemont和粳稻秀水11三类代表性优质品种杂交,探讨通过亚(品)种间淀粉粘滞特性转移来培育优质早籼稻的可行性。结果表明,3种供体衍生的低AAC品系间淀粉粘滞性相似,但中等AAC品系间差异显著。浙辐504/IR64籼籼杂交后代,RVA谱变异丰富,易筛选到与IR64淀粉粘滞性相同的新品系;浙辐504/Lemont籼爪杂交后代,只选择到个别与Lemont淀粉粘滞性相似的新品系;浙辐504/秀水11籼粳杂交后代,未发现与粳稻秀水11淀粉粘滞性相似的新品系。     

利用RVA谱快速鉴别不同表观直链淀粉含量早籼稻的淀粉粘滞特性

采用粘度速测仪分析了浙江省新近培育的早籼稻新品种（系）的淀粉粘滞特性,结果表明不同品种（系）具有特征性RVA谱。依消减值可有效区分出品种（系）表观直链淀粉含量（AAC）的高低。低AAC品种（系）的消减值一般为负值,中等或高AAC品种（系）的消减值为正值。中等AAC品种（系）间食用品质的优劣,可根据消减值和崩解值判断。RVA谱的崩解值与胶稠度和米饭口感相关,消减值与米饭质地关联。上述结果表明, RVA谱特性可望作为理化标记在优质稻米育种中发挥重要作用。     

稻米淀粉粘滞性谱特征的表现及其遗传

通过对水稻F[sub]2[/sub]无性系群体及大量品种（系）的RVA谱的测定,研究了稻米淀粉RVA谱的类型及遗传。结果表明：（1）RVA谱可分为A~F六种类型,糯稻的特征图谱为A型,籼稻的特征图谱有B、C、D、E、F五种类型,粳稻有D、E、F三种类型。（2）稻米的表观直链淀粉含量（AAC）不同,RVA谱则不同。稻米的AAC相同,RVA谱也可不同,在低、中AAC类型中,RVA谱的差异能反映品种食味品质的差异。（3）4个杂交稻组合的RVA谱表现出相同的特点,除最高粘度和起浆温度外,其他特征值均介于双亲之间,表明杂交稻米品质改良要求不育系与恢复系的改良同步进行。（4）在F[sub]2[/sub]无性系群体中,RVA谱各特征均呈连续分布,最高粘度是典型的数量性状遗传,热浆粘度、冷胶粘度、崩解值、消减值、回复值都可能是由一对主效基因和若干微效基因共同控制的遗传。     

转Bt基因杂种后代的稻米直链淀粉含量与粘滞性淀粉谱分析

以克螟稻TS5为亲本与5个感虫亲本作正反杂交配组．分析了各组合后代抗虫株系和非抗虫株系及其双亲的直链淀粉含量（AAC）和粘滞性淀粉谱（RVA谱）。结果表明．杂种后代的AAC基本介于双亲之间，且偏向于高值亲本。AAC与最粘时间（PT）呈极显著正相关（0．7929）．与消减值（SBV）、最高粘度（PKV）、热浆粘度（HPV）、冷胶粘度（CPV）呈显著或极显著正相关，与崩解值呈负相关；杂种后代的RVA谱特征值与其双亲相比．无明显变化．但部分性状有所改善。这为抗虫杂交水稻的育种提供了参考依据。     

利用RVA谱快速鉴别不同表现直链淀粉含量早籼稻的淀粉粘滞特性

采用粘度速测仪分析了浙江省新近培育的早籼稻新品种（系）的淀粉粘滞特性，结果表明不同品种（系）具有特征性RVA谱。依消减值可有效区分出品种（系）表观直链淀粉含量（AAC）的高低。低AAC品种（系）的消减一般为负值，中等或高AAC品种（系）的消减值为正值。中等AAC品种（系）间食用品质的优劣，可根据消减值和崩解值判断。RVA谱的崩解值与胶稠度和米饭口感相关，消减值与米饭质地关联。上述结果表明，RVA谱特性可望作为理化标记在优质稻米育种中发挥重要作用。     

水稻糯性突变对淀粉理化特性的影响

比较了籼、粳两个糯性突变品种与原亲本品种淀粉的理化特性。糯性突变后除了直链淀粉含量显著降低外,淀粉的糊化温度变高、胶稠度增大、RVA谱(rapid viscosity analyzer)参数下降。RVA谱参数降低的幅度从高到低依次是消减值>回复值>冷胶粘度>热浆粘度>最高粘度>崩解值,表明控制直链淀粉含量的Wx位点对淀粉糊化特性和粘滞性是有影响的,存在多效性。同时,两个糯稻品种之间的RVA谱差异较大,其中崩解值和最高粘度差值均大于糯性突变对它们的影响,说明除直链淀粉外,支链淀粉也影响淀粉的理化特性。对Wx位点鉴定的结果显示扬辐糯4号wx基因第一内含子剪切位点＋1位的碱基由原品种的G突变成了T,扬糯2号与其原品种相同(均为T);两个糯稻突变品种wx基因前导区的(CT)n微卫星重复序列与原品种相比都发生了变化。     

稻米淀粉RVA谱特征与品质性状的相关性

 通过对106份水稻材料稻米外观品质、蒸煮品质和RVA谱特征值的测定,研究了淀粉黏滞性（RVA谱）特征值与各项品质指标的相关关系。RVA谱特征值与外观品质中的垩白率关系最为密切,其中垩白率与崩解值(BDV)和消减值(SBV)的相关系数分别为-0.43**和0.40**;RVA谱特征值与低直链淀粉含量(AC)品种和糯稻品种的蒸煮品质指标呈显著或极显著相关,与中高直链淀粉含量品种的指标相关性不显著,特别是高直链淀粉含量品种的AC与RVA谱特征值相关性均不显著,而糯稻品种的AC与RVA谱特征值（BDV和 SBV除外）的相关系数均在0.85以上。由此认为,水稻品种的AC越低,AC与RVA谱特征值的关系越密切。     

弱光胁迫对不同基因型水稻稻米淀粉RVA谱特征值及直链淀粉含量的影响

以Ⅱ优498、冈优188、冈优527、川香9838、冈优906为材料,研究了弱光胁迫对稻米淀粉RVA谱特征值及直链淀粉含量的影响。结果表明,返青分蘖期和孕穗期遮荫均影响了淀粉RVA谱特征值及直链淀粉含量,孕穗期遮荫影响程度高于返青分蘖期。随着光照强度的减弱,最高黏度、最终黏度、崩解值降低,而消减值增加,直链淀粉含量在弱光下表现为返青分蘖期增加,孕穗期减少的趋势。不同基因型稻米淀粉RVA谱特征值对弱光的反应不同,Ⅱ优498、冈优906经遮荫处理后RVA谱特征值与对照差异不显著,而其余3个品种遮荫处理的RVA谱特征值与对照差异显著。冈优527、冈优188和川香9838的直链淀粉含量对弱光较敏感。综合淀粉RVA谱特征值和直链淀粉含量,Ⅱ优498和冈优906受弱光影响较小,较适应四川弱光寡照环境条件。     

水稻胚乳外观云雾性状形成基础及其快速识别条件分析

以早籼稻新品种(系)、杂交水稻不育系、恢复系及其衍生的部分杂交组合为材料进行研究,发现云雾性状是低表观直链淀粉含量品种（系）特有的胚乳外观,其形成的原因和胚乳内淀粉的形态和结构有关。种子老化试验表明,种子水分和老化是快速识别云雾性状的两个重要条件。育种实践中可采用高温烘干和高温保湿预处理两种方法来快速识别胚乳云雾性状,并以此作为标记,早期特异性剔除低表观直链淀粉材料。     

水稻胚乳外观云雾性状形态基础及其快速识别条件分析

以早籼稻新品种（系）、杂交水稻不育系、恢复系及其衍生的部分杂交组合为材料进行研究，发现云雾性状是低表观直链淀粉含量品种（系）特有的胚乳外观，其形成的原因和胚乳内淀粉的形态和结构有关。种子老化试验表明，种子水分和老化是快速识别云雾性状的两个重要条件。育种实践中可采用高温烘干和高温保湿预处理两种方法来快速识别胚乳云雾性状，并以此作为标记，早期特异性剔除低表观直链淀粉材料。     

Performance and Inheritance of Rice Starch RVA Profile Characteristics

The classification and inheritance of rice starch RVA profiles were studied by testing RVA profiles of F2 clonally propagated population and some varieties, including japonica, indica, and glutinous types. All the RVA profiles of accessions could be divided into six kinds based on the cluster analysis, that is A, B, C, D, E and F. Feature profile of sticky variety was type A. The profiles of indica varieties could be presented as B, C, D, E and F types and that of japonica varieties fell into D, E and F types.RVA profiles of the rice were mainly affected by apparent amylose content (AAC), but the difference of RVA profiles could also be detected in the varieties with similar AAC. The close relationship between RVA profile indices and sensory of low or middle AAC varieties suggested that the RVA profiles can be used as indirect index to evaluate eating and cooking quality. In four hybrid combinations, the component indices of RVA profiles of F1 were between those of its parents except peak viscosity and pasting temperature. Also, in F2 clonally propagated population, all the components of the RVA profiles showed continuous segregation,suggesting that all of them were controlled by a series of minor genes, although Wx gene may play an important role in determining the RVA profiles. These results may provide some new information useful for rice quality breeding program.     

施氮量对机插稻主要米质性状的影响

以粳型超级稻宁粳3号和常规粳稻镇稻11号为材料,在机械插秧条件下,研究施氮量(0、90、180、270、360 kg/hm2)对粳型超级稻主要米质性状及淀粉粘滞谱(RVA谱)特征的影响。结果表明:施氮量对两个品种的稻米加工品质、营养品质、蒸煮食味品质及淀粉RVA谱3个曲线峰值的影响达到显著或极显著水平,对淀粉RVA谱其他特征参数的影响因不同品种而异;增加施氮量使两品种外观品质变差。随施氮量的增加,两个品种的糙米率、精米率、整精米、精米蛋白质含量呈增加趋势,而稻米的直链淀粉含量、食味值和淀粉RVA谱曲线峰值(峰值黏度、热浆黏度和冷胶黏度)呈现下降趋势。表明增施氮肥在提高粳型超级稻和常规粳稻加工和营养品质的同时,降低了稻米食味品质,并使稻米淀粉粘性变劣。     

结实期籽粒乙烯释放速率和1-氨基环丙烷-1-羧酸浓度与稻米外观品质的关系

 为阐明水稻籽粒乙烯与稻米外观品质的关系，试验采用10个不同基因型的水稻材料，测定了结实期籽粒乙烯释放速率、1 氨基环丙烷 1 羧酸（ACC）浓度和稻米的外观品质，分析了它们之间的关系并用化学调控等方法进行验证。结果表明，灌浆中后期籽粒乙烯释放速率和ACC浓度与稻米的垩白粒率和垩白度均呈极显著的正相关。籽粒中ACC浓度低的品种，胚乳淀粉体排列紧密，间隙较小；而籽粒中ACC浓度高的品种，淀粉体排列疏松，间隙大。在灌浆中后期分别用1 μmol/L ACC 处理稻穗，稻米的淀粉体排列变疏松，垩白粒率、垩白大小和垩白度均显著增加，用1 μmol/L氨基 乙氧基乙烯基甘氨酸（ACC合成酶抑制剂）处理稻穗，结果则相反。结实期进行轻干 湿交替灌溉，降低了籽粒乙烯释放速率、ACC浓度和垩白度。说明籽粒中乙烯和ACC对稻米胚乳淀粉结构和外观品质起重要的调控作用，通过品种选育、化学调控和灌溉等措施降低籽粒乙烯释放速率和ACC浓度，可以改善稻米的外观品质。     

Relationships of Ethylene Evolution Rate and 1-Aminocylopropane-1-Carboxylic Acid Concentration in Grains during Filling Period with Appearance Quality of Rice

To elucidate the relationship between ethylene evolution from the grains and the appearance quality of rice,ten different rice genotypes were used to determine the ethylene evolution rate,1-aminocylopropane-1-carboxylic acid(ACC)concentration in grains during grain filling and the appearance quality of rice,and the effects of chemical regulators on concentrations of ethylene and ACC in the grains during grain filling were also investigated to verify the roles of ethylene in the rice quality formation.The ethylene evolution rates and ACC concentrations in grains during the mid and late grain filling stages were very significantly and positively correlated with chalky kernel percentage and chalkiness.The cultivars with a low ACC concentration in grains exhibited a close amyloplast arrangement and small space between starch granules,whereas those with a high ACC concentration in grains showed a loose arrangement and wide space between the granules.Application of 1μmol/L ACC to panicles at mid and late grain filling stages significantly loosened amyloplast arrangement and increased chalky kernel percentage,chalky area and chalkiness,and the results were reversed when 1μmol/L amino-ethoxyvinylglycine,an inhibitor of ACC synthesis enzyme,was applied to panicles.A practice of moderate dry-wet alternate irrigation reduced ethylene evolution and ACC concentration in grains and thereby reduced chalkiness. The results suggested that ethylene and ACC in grains play an important role in the endosperm structure and appearance quality of rice,and the appearance quality would be improved by reducing ethylene evolution and ACC in grains through either variety breeding and selection,or chemical regulations or cultivation techniques.     

优质水稻品种越光(Koshihikari)中控制稻米淀粉RVA谱特征值的QTL分析

利用南京11×Koshihikari RIL群体在南京两年的种植结果,检测与稻米淀粉RVA谱特征值峰值黏度、最低黏度、最终黏度、崩解值、消减值、峰值时间和糊化温度相关加性和上位性效应QTL,并分析其表达稳定性。结果表明,7个稻米淀粉RVA谱特征值在两年中均呈连续分布,且存在超亲遗传现象。共检测到8个具有加性效应的QTL与稻米6项淀粉RVA谱特征值有关,两年中能重复出现的QTL有6个,即qTPV-6、qFPV-6、qBDV-6、qSBV-6、qPKT-6和qPT-6,分别控制最低黏度、最终黏度、崩解值、消减值、峰值时间和糊化温度,两年的平均贡献率分别为46.4%、60.3%、31.1%、71.9%、38.5%和12.4%,而qSBV-8和qPT-5仅在1年中被检测到,环境稳定性差。此外,还检测到5对影响稻米淀粉RVA谱特征值的QTL具有上位性效应,互作既发生在相同染色体上也发生在不同染色体之间,但贡献率较小,且受环境的影响较小。控制稻米淀粉RVA谱特征值的稳定、主效QTL,可为Koshihikari中稻米优良蒸煮食味品质相关基因的育种利用提供基础。     

Relationship between the Starch Properties of White-Core Tissue and Polishing Characteristics in Brewers’ Rice Kernels

References

The kernels of Hattan-nishiki No. 1 and Kairyo-omachi have larger air spaces in the white-core tissue and are broken easily during the process of polishing when compared with those of Senbon-nishiki and Yamada-nishiki. The polishing characteristics of brewers’ rice kernels are closely related with the structure of the white-core tissue of kernels. In this study, the varietal differences in the starch properties of white-core tissue of brewers’ rice kernels on polishing characteristics were studied. The starch properties were studied by rapid visco analysis (RVA) and differential scanning calorimetry (DSC); the amylose content of the rice flour of each variety was also analysed. No significant differences were observed in the amylose content among the four varieties. The two RVA parameters, peak viscosity and breakdown, were higher in Hattan-nishiki No. 1 and no significant differences were observed in them among Senbon-nishiki, Yamada-nishiki and Kairyo-omachi. The DSC parameters, gelatinization onset and peak and conclusion temperatures, were higher in Hattan-nishiki No. 1, lower in Senbon-nishiki and Yamada-nishiki, and intermediate between them in Kairyo-omachi. These results suggest that the polishing characteristics of brewers’ rice kernels are related with not only the endosperm structure but also the starch property of white-core tissue, except for Kairyo-omachi.