【作者】 陈书强；

【导师】 徐正进；

【作者基本信息】 沈阳农业大学 ， 作物生物技术， 2008， 博士

【摘要】 直立穗型是水稻理想株型的重要内容,它与水稻的群体结构、产量潜力和品质关系密切,是继矮秆和理想株型后粳稻适应高产要求的重要形态改良。但是直立穗型基因遗传近年来研究进展较慢。直立穗型基因除使穗型直立外,其它功能尚不完全清楚。直立穗型增加产量潜力同时,也引起了穗内不同粒位间籽粒的粒重和品质的变化。穗型和粒位对穗内品质整齐度影响有多大,目前相关研究较少。本文利用辽粳5号与丰锦杂交高世代(F₁₃)构建的近等基因系为材料,用分子标记方法对所构建的直立穗型近等基因系遗传背景进行检测,结果表明直立穗型近等基因系的遗传背景相似率达到了99.69%,在分子水平上是一对较理想的近等基因系。用直立穗型近等基因系研究了粳稻直立穗型基因对农艺性状的影响。并选用典型的直立穗型和弯曲穗型粳稻品种,研究了穗上不同粒位籽粒的品质性状差异及其分布特点。结果如下:1直立穗型基因除了使穗型直立外,还具有使植株矮化、穗长变短、叶型直立、叶片变短变宽等作用。带有直立穗型显性基因的品种,在抽穗期和成熟期拥有较大的叶面积指数和较高的叶绿素含量及生物量。直立穗型基因能增加穗颈大、小维管束数和倒2节间大、小维管束数,并能使直立穗型品种具有较大的库源比和较高的茎鞘物质输出率和转换率。2不同基因型品种的抗倒伏能力是不同的。直立穗型品种的第3、4节间倒伏指数明显小于弯曲穗型品种。直立穗型品种的株高较低,各节间的粗度、横切面积和茎壁厚度都较大,各节间茎秆干重、叶鞘干重、单位节间干重和单位茎壁干重也均较大。3直立穗型基因能使一次枝梗上的二次枝梗数增加,从而增加了二次枝梗上的颖花数和受精颖花数,使整穗的总颖花量、受精颖花量、着粒密度和库容量增加,从而达到增加产量的目的。但是直立穗型基因也使整穗的成粒率、受精颖花率、千粒重和谷粒充实率降低。尤其直立穗型基因在杂合遗传背景下,与产量有关的各项指标表现都较高,表明直立穗型基因能使粳稻F₁代杂种显著提高产量。直立穗型基因增加了穗中部和下部的二次枝梗数及其粒数,使直立穗型品种穗型指数变小,穗型变得紧密,下部着粒密度显著增加。4不同基因型品种在下部二次枝梗上第2、3粒位籽粒增重过程的差异较大。直立穗型品种下部二次枝梗上第2、3粒位籽粒增重过程缓慢,时间较长,增重过程表现出“慢—快—慢—快—慢”的特点,而弯曲穗型品种下部二次枝梗上第2、3粒位的增重表现比较匀速,直到达到最大粒重。从而导致了直立穗型品种整穗的灌浆速度和进程要比弯曲穗型品种慢,这可能是由于直立穗型基因使直立穗型品种下部产生较多的二次枝梗粒数（劣势粒）所致。5直立穗基因可能从幼苗开始生长阶段就有所表达,使得幼苗在株高、叶形态和干物质重上表现出差异。内源赤霉素、脱落酸、生长素和细胞分裂素含量在各生育时期的差异是使近等基因系在形态性状上表现出差异的内在生理原因。近等基因系在园秆拔节期喷施不同浓度外源GA₃和多效唑(PP₃₃₃)后,株高改变较大,但穗型变化幅度较小,ZF₁₃和WF₁₃的矮秆基因和直立穗型基因对这两种激素的反应不同。6穗型特征与品种的粒重和结实率没有多大联系,粒重和结实率通常为:一次枝梗上籽粒＞二次枝梗上籽粒,上部枝梗籽粒＞中部枝梗籽粒＞下部枝梗籽粒。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对粒重有显著的影响。一次枝梗上6个粒位籽粒的粒重和结实率基本以第6、5、4粒位较高,第2粒位最低,二次枝梗上3个粒位以第1粒位最高,第2粒位最低。直立穗型品种穗内不同粒位间粒重和结实率的变异大于弯曲穗型品种。7穗型特征与蛋白质含量、直链淀粉含量和食味值高低无直接必然的联系,但是对穗不同部位间这些指标及其粒位顺序有较大影响。对3个直立穗型品种而言,蛋白质含量、直链淀粉含量表现为穗下部＞中部＞上部,食味值则相反,而对3个弯曲穗型品种而言,蛋白质含量、直链淀粉含量的表现规律不明显,食味值表现为穗上部＞中部＞下部。同一稻穗不同枝梗间相比,着生在二次枝梗上的稻米蛋白质含量相对较高、直链淀粉含量、胶稠度和食味值相对较低,而着生在一次枝梗上的籽粒则相反。同一枝梗间的不同着粒部位相比,下部二次枝梗第2、3粒位的蛋白质含量较高、食味值较低,中上部一次枝梗1～6粒位的蛋白质含量较低、食味值较高,而直链淀粉含量在粒位间规律不明显。直立穗型品种单一稻穗不同粒位间的差异大于弯曲穗型品种,其主要原因可能是直立穗型品种着粒密度过大。8粳稻的穗型特征与籽粒的碾米品质有直接的联系,弯曲穗型品种的碾米品质好于直立穗型品种。一次枝梗上籽粒的碾米品质好于二次枝梗上籽粒,一次枝梗上籽粒的碾米品质是下部好于上部,而二次枝梗上籽粒的碾米品质是上部好于下部。碾米品质的好坏与其颖花在穗上的开花顺序有密切联系,早开花的籽粒碾米品质较差,而晚开花的籽粒碾米品质相对较好。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对出糙率、精米率和整精米率有显著影响。糙米率的粒位变异是弯曲穗型品种大于直立穗型品种,精米率的粒位变异大小因品种而异,而整精米率的粒位变异是直立穗型品种大于弯曲穗型品种。9粳稻的穗型特征与品种的粒形有着直接的联系,弯曲穗型品种的粒形要好于直立穗型品种。一次枝梗上籽粒的粒形优于二次枝梗上籽粒,一次枝梗上籽粒的粒形是上部好于下部,而二次枝梗上籽粒的粒形是下部好于上部。稻穗上早开花籽粒的粒形优于晚开花籽粒。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对长宽比和长厚比的影响不显著。直立穗型品种穗内籽粒长宽比的粒位变异大于弯曲穗型品种,而长厚比的粒位变异大小因品种而异。10粳稻品种的穗型特征与品种间的垩白粒率、垩白度和透明度高低无直接必然的联系。二次枝梗上籽粒的垩白粒率和垩白度高于一次枝梗上籽粒,透明度则相反。同一稻穗不同部位间籽粒相比,垩白粒率、垩白度基本都表现为下部＞中部＞上部,透明度则基本相反。一次枝梗上6个粒位的垩白粒率和垩白度第1、5、6粒位较低,第2、3粒位较高,二次枝梗上3个粒位的垩白粒率和垩白度第1粒位最低,第2粒位最高,透明度则相反。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对垩白粒率、垩白度和透明度有显著影响。6个品种穗内籽粒的垩白粒率、垩白度和透明度的粒位变异大小因品种而异。11穗型特征与品种间的脂肪酸含量、清蛋白含量、球蛋白含量、醇溶蛋白含量和谷蛋白含量高低无直接必然的联系。一次枝梗上籽粒的清蛋白含量、醇溶蛋白含量和谷蛋白含量低于二次枝梗上籽粒,脂肪酸含量和球蛋白含量则相反。同一稻穗不同部位间籽粒比较,脂肪酸含量、球蛋白含量、醇溶蛋白含量和谷蛋白含量大致表现为下部＞中部＞上部,而清蛋白含量则相反。籽粒的可溶性蛋白含量和脂肪酸含量高低与颖花在穗上的开花顺序有密切联系,不同粒位上籽粒的蛋白质含量高低因可溶性蛋白质的种类而异。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对脂肪酸含量和可溶性蛋白含量有显著影响。6个品种穗内籽粒的脂肪酸含量和可溶性蛋白含量的粒位变异大小因品种而异。12粳稻的穗型特征与品种的淀粉RVA谱特征值无直接必然的联系。一次枝梗上籽粒的淀粉粘滞特性优于二次枝梗上籽粒,穗上部籽粒的淀粉粘滞特性好于穗中部和下部籽粒,淀粉粘滞特性好坏与其颖花在穗上的开花顺序有密切联系,早开花籽粒（第1、6、5粒位）的淀粉粘滞特性强于晚开花籽粒（第2粒位）。一次和二次枝梗与上部、中部和下部枝梗这两类粒位之间的互作对峰值黏度、热浆黏度、崩解值、冷浆黏度、消减值、回复值、起浆温度和峰值时间有显著影响。6个品种穗内籽粒的淀粉RVA谱特征值的粒位变异大小因品种而异。13简单相关分析表明穗内不同粒位上籽粒的食味值与粒重、糙米率、精米率、整精米率、粒长、粒宽、长厚比、透明度、球蛋白含量、胶稠度、峰值黏度、热浆黏度、崩解值、冷胶黏度和回复值呈显著正相关,与垩白率、垩白度、清蛋白含量、醇溶蛋白含量、谷蛋白含量、总蛋白含量和脂肪酸含量、消减值、起浆温度和峰值时间呈显著负相关,而与长宽比、直链淀粉含量相关性不大。通过典型相关分析得出穗内不同粒位间籽粒的蒸煮食味品质与淀粉RVA谱特征和碾米品质间的相关性最高,其次与垩白性状的相关度较高,与营养品质和粒形性状的相关性相对较低一些。更多还原

【Abstract】 Erect panicle type of Japonica rice is an important component of ideal rice plant type, which is closely related to population structure,yield potential and grain quality.Erect panicle type,which followed dwarf type and ideal plant type,is important morphological character development that Japonica rice adapts to high-yield requirement.But advance on genetic effects of erect panicle type rice has progressed slowly in recent years.It is still unclear whether erect panicle gene（EP） has other functions except that EP makes panicle shape erect.Erect panicle type can increase yield potential and meanwhile it can result in the change of grain weight and quality in the grains between different grain positions of panicle. Few studies have determined that how much are the effect of panicle type and grain position on the regularity degree of quality within a panicle.Genetic background of the near isogenic Lines（NILs） derived from Fengjin high generation of cross(F₁₃) and Liaogeng 5 analyzed by molecular marker method.Results showed the similarity of genetic background of NILs containing EP was 99.69%.It was a pair of rather ideal NILs.The effects of EP on agronomic traits of Japonica rice were studied by NILs.With typical japonica cultivars with erect panicle and curved panicle as the materials,the difference of rice grain quality and their position distributions within a panicle between two types panicle of japonica rice were researched.The main results were shown as follows:1 The erect panicle gene of rice also made plant height dwarf,panicle length short,leaf posture erect,leaves wide and short except that made panicle type erect.The varieties carrying dominant erect panicle gene had more leaf area index,higher chlorophyll content and rice biomass at 50%-heading and maturity stage.EP increased the number of large or small vascular bundles in panicle neck and the second internode from the top,which made grain-leaf ratio and translocation ratio of matter in stems and sheaths of erect particle varieties increase.2 Lodging resistance in different genotype rice cultivars were difference.Index of lodging at the 3^rd and 4^th internode in erect panicle cultivars carrying EP was significantly decreased,which resulted from its related traits such as lower plant height,larger internode thickness,larger area of cross section and wall thickness,higher dry weight of culm,leaf sheath,the dry weight of culm wall and internode per unit.3 EP increased the number of secondary branch on primary branch,consequently EP increased total number of spikelets and fertilized spikelet number on secondary branch.EP could raise yield by increasing total number of spikelets,total amount of fertilized spikelets, grain density and sink size within whole panicle.EP could decrease filled grain rate,spikelet fertilization rate,1000-grain weight and grain filling rate within whole panicle.EP increased especially yield from F₁ hybrids of japonica rice in the heterozygous genetic background.EP increased secondary branch number and grains on the secondary branches at the middle and base parts of a panicle.In erect panicle cultivars,panicle trait index was reduced,ear shape compacted and grain density at the base part of a panicle increased.4 Difference of grain weight-increasing process between two different genotype cultivars mainly presented difference of the 2^nd and 3^rd grain positions of secondary branch at lower part of rice.The grains positions of erect panicle cultivars had longer filling time and slower grain weight-increasing process which presented the characteristic of slow-fast-slow-fast-slow.The grains positions of curve panicle cultivars had relatively stable filling rate and the grain weight of these positions was at its most.Grain filling speed and process of erect panicle cultivars was slower than that of curve panicle cultivars,which resulted from a large amount of grains,especially inferior grains,on the secondary branches at lower part of erect panicle cultivars.5 The expression of EP began from seedling’s establishment.The difference mainly presented plant height,leaf morphology and plant dry weight.The physiological mechanism which NILs differenced in morphological traits were that the contents of endogenous gibberellic acid（GA₃）,abscisic acid（ABA）,auxin（IAA）and cytokinins（ZR） differenced in each growth stage.Change of plant height exceeded change of panicle type after NILs in the shooting stage were separately treated with various concentration of exogenous GA₃ and paclobutrazol(PP₃₃₃).The effects of ZF₁₃ carrying dwarf gene and WF₁₃ carrying erect panicle gene on the two kinds of hormones were difference.6 Panicle type had little correlation with grain weight and seed setting rate of cultivars. The order of grain weight and seed setting rate among different grain positions was as follows: primary rachis>secondary;rachis top >middle>bottom rachis.The significant difference was found in grain weight among grains located on different rachises（primary and secondary rachises） and panicle position,i.e.top,middle,and bottom.The fourth to sixth grain of primary branch showed the highest grain weight and seed setting rate,the second grain the lowest.The first grain of secondary branch showed the least grain weight and seed setting rate,the second grain the greatest.The difference of grain weight and seed setting rate at different grain positions in erect panicle was higher than that in curved panicle.7 Panicle type had considerable influence on PC,AC,TQ at the different parts of panicle, for erect panicle cultivars,PC and AC increased with the grain position from the upper to the lower parts,while TQ showed reverse trend;for curved panicle ones,PC and AC showed no regular trend,but TQ was the same as that of erect panicle culfivars.In the same panicle,the PC of secondary branches was higher than that of primary branches,while AC and TQ behaved reversely.In the same rachis branches,the 2^nd and 3^rd grain of secondary branch at lower part had higher PC and lower TQ,the 1^st to 6^th grains of primary branch at mid and upper part had lower PC and higher TQ,no rule was found for AC at different grain positions of panicle.The difference of referred quality traits at different grain positions in erect panicle was higher than that in curved panicle,resulting from higher grain density in erect panicle. Results from this study will facilitate erect panicle cultivars in rice breeding for quality in Northeast China.8 Panicle type of Japonica rice had direct relation with milling quality of the grain. Milling quality of the grains for curved panicle cultivars was better than those of erect panicle ones.The indexes of milling quality of the grains on a primary branch were better than those on a secondary.The indexes of milling quality of the grains on a primary branch at bottom part were better than those at top part,but the grains on a second branch showed reverse trend. The milling quality of the spikelets that flowered earlier was superior to those flowered late. The change in milling quality was very identical with the following sequence.The significant difference was found in blown rice percentage,milled dee percentage and head rice percentage among grains located on different rachises（primary and secondary rachises） and panicle position,i.e.top,middle,and bottom.Positional variations in blown rice percentage for curved panicle cultivars was greater than that of erect panicle ones.While positional variations head rice percentage showed reverse trend.Positional variations in milled rice percentage varied with cultivars.9 Panicle type of Japonica rice had direct relation with brown rice shape.Brown rice shape for curved panicle cultivars was better than that of erect panicle ones.The indexes of brown rice shape on a primary branch were better than those on a secondary.The indexes of brown rice shape on a primary branch at top part were better than those at bottom part,while the grains on a second branch showed reverse trend.The brown rice shape of the spikelets that flowered earlier was superior to those flowered late.The significant difference was not found in length-width ratio and length-thickness ratio among grains located on different rachises（primary and secondary rachises） and panicle position,i.e.top,middle,and bottom. Positional variations in length-width ratio for erect panicle cultivars was greater than that of curved panicle ones,while positional variations in length-thickness ratio varied with cultivars.10 Particle types of japonica rice had no direct correlation with chalky grain percentage （CGP）,chalkiness degree（CD） and transparence degree（TD） in the grains between the six japonica cultivars tested.All primary branches on a panicle were evenly divided into three parts of the upper,middle and basal.The grains were numbered as 1 to 6 on a primary branch and 1 to 3 on a secondary branch from the top to base.Generally,CGP and CD on the branches at the basal part of a panicle exhibited the greatest,at the middle part the middle, and at the upper part the least.CGP and CD for the grains on a secondary branch were greater than those on a primary branch at the same part of a panicle.TD was just the opposite.CGP and CD for the grain 1,5 and 6 on the primary branch showed the lowest,the grain 2 and 3 the highest.CGP and CD were the least for the grain 1 and the greatest for the grain 2 on a secondary branch within a panicle.Type panicle of japonica rice was not directly related to appearance quality of cultivar.The variation in appearance quality of different grains within a panicle was closely related to the flowering order of rice grains on the rachis branches.11 Panicle types of japonica rice had no direct correlation with fatty acid,albumin, globulin,prolamin,and glutelin content in the grains between the six japonica cultivars tested. Generally,fatty acid,globulin,prolamin,and glutelin content on the branches at the basal part of a panicle exhibited the greatest,at the middle part the middle,and at the upper part the least.Albumin content was just the opposite.The contents of albumin content,prolamin and glutelin for the grains on a secondary branch were greater than those on a primary branch at the same part of a panicle,while fatty acid and globulin content showed reverse trend.The variation in soluble protein and fatty acid content of different grains within a panicle’was closely related to the flowering order of rice grains on the rachis branches.The variation of protein content varied with soluble protein profile.The significant difference was found in fatty acid and soluble protein content among grains located on different rachises（primary and secondary rachises） and panicle position,i.e.top,middle,and bottom.Positional variations in fatty acid and soluble protein content of the grains between the six japonica cultivars tested varied with cultivars.12 Panicle types of japonica rice had no direct correlation with RVA profile parameters of rice cultivars tested.Starch viscosity characteristics for the grains on a primary branch were better than those on a secondary branch at the same part of a panicle.Starch viscosity characteristics for the grains at top part were better than those at middle and bottom parts. The variation in starch viscosity characteristics of different grains within a panicle was closely related to the flowering order of rice grains on the rachis branches.Starch viscosity characteristics for the grain 1,6 and 5 of the spikelets that flowered earlier were superior to those for the grain 2 of the spikelets that flowered late.The significant difference was found in RVA profile parameters including peak viscosity,hot paste viscosity,breakdown,cool paste viscosity,setback,consistence,gelatinization temperature and peak time among grains located on different rachises（primary and secondary rachises） and particle position,i.e.top, middle,and bottom.Positional variations in RVA profile parameters of rice varied with cultivars.13 The results of a single factor correlation analysis showed that TQ at different grain positions within a panicle had significant positive correlation with grain weight,blown rice percentage,milled rice percentage,head rice percentage,grain length,grain width,ratio of grain length to thickness,transparence degree,globulin content,gel consistence,peak viscosity,hot paste viscosity,breakdown,cool paste viscosity and consistence in the grains, and had significant negative correlation with chalky grain percentage,chalkiness degree, albumin,prolamin,glutelin,total protein,and fatty acid content,setback,gelatinization temperature,and peak time in the grains,and had little correlation with length-width ratio and amylose content in the grains.RVA profile parameters and milling quality of the grain showed most significant correlation than other traits with cooking and eating quality of rice at different grain positions within a panicle,while nutritional quality and grain shape showed lower correlation with cooking and eating quality of rice.更多还原