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1.
水分胁迫对水稻籽粒灌浆及淀粉合成有关酶活性的影响 总被引：7，自引：1，他引：6
【目的】探索不同水稻抗旱品种在水分胁迫条件下籽粒灌浆特性及有关淀粉酶活性的变化规律。【方法】选用抗旱性不同的3个杂交水稻品种,分别在正常供水和水分胁迫条件下,研究水稻茎鞘物质运转、籽粒灌浆和淀粉合成有关酶活性。【结果】水分胁迫下,抽穗期和成熟期茎鞘干物重以及抽穗后茎鞘物质输出量、输出率、转化率均下降;籽粒生长潜势、最大灌浆速率和平均灌浆速率降低,籽粒生长活跃期缩短,各品种达最大灌浆速率的时间提前;籽粒灌浆过程中可溶性淀粉合成酶（SSS）、Q酶和ADPG焦磷酸化酶3种酶活性都不同程度的被抑制。各性状抗旱性强的品种均比抗旱性弱的品种减少的幅度小。抽穗期茎鞘干物重、抽穗后茎鞘干物质输出量、输出率和转化率均与籽粒产量呈显著或极显著正相关。【结论】在水分胁迫下抗旱性强的品种具有较高的茎鞘物质输出率和转化率、籽粒灌浆速率及淀粉合成有关酶活性,是产量降低较少的生理基础。 相似文献
2.
花后轻干-湿交替灌溉提高水稻籽粒淀粉合成相关基因的表达 总被引：10，自引：0，他引：10
【目的】水稻籽粒灌浆是光合同化产物向籽粒运输并合成淀粉的生理过程,决定水稻结实率、粒重高低及品质优劣。籽粒灌浆过程不仅受遗传因素的影响,而且受到温度和水分等环境因子的调节。灌溉是水稻生产上一项重要的技术,对水稻产量的形成有重要调控作用。但有关花后灌溉方式对水稻籽粒淀粉合成相关基因表达的影响,缺乏研究。本研究旨在探讨花后干湿交替灌溉对水稻籽粒灌浆的影响并阐明其分子机理。【方法】2012-2013年以两优培九（两系杂交籼稻）和扬粳4038（杂交粳稻）为材料种植于土培池,自抽穗（50%穗伸出剑叶叶鞘）至成熟设置3种灌溉方式处理：（1）常规灌溉（conventional irrigation,CI）,保持浅水层,收获前一周断水;（2）轻干-湿交替灌溉（alternate wetting and moderate soil drying,WMD）,自浅水层自然落干至土壤水势达-20 kPa时,灌水1-2 cm,再自然落干至土壤水势为-20 kPa,再上浅层水,如此循环;（3）重干-湿交替灌溉（alternate wetting and severe soil drying,WSD）,自浅水层自然落干至土壤水势达-40 kPa时,灌水1-2 cm,再自然落干至土壤水势为-40 kPa,再上浅层水,如此循环。观察花后干湿交替灌溉对水稻强、弱势粒灌浆速率、粒重和淀粉合成相关酶活性的影响,并应用实时荧光定量PCR技术测定编码这些酶基因的相对表达量。【结果】强势粒的平均灌浆速率、粒重、淀粉合成有关的蔗糖合酶（SuS）、腺苷二磷酸葡萄糖焦磷酸化酶（AGP）、淀粉合酶（StS）和淀粉分支酶（SBE）等相关酶活性以及蔗糖合酶基因SuS2、SuS4,腺苷二磷酸葡萄糖焦磷酸化酶基因AGPL1、AGPL2、AGPL3、AGPS2,淀粉合酶基因SSI、SSIIa、SSIIc、SSIIIa和淀粉分支酶基因SBEI、SBEIIb的相对表达量在3种灌溉方式处理间没有显著差异。与常规灌溉相比,轻干-湿交替灌溉处理显著增加了弱势粒的平均灌浆速率、粒重、4种籽粒淀粉合成相关酶活性和除AGPL1外各基因的相对表达量,重干-湿交替灌溉处理则显著降低弱势粒的平均灌浆速率、粒重、各淀粉合成相关酶活性和基因的相对表达量。两供试品种试验结果趋势一致。相关分析表明,弱势粒的平均灌浆速率、粒重与SuS、AGP、StS、SBE活性以及SuS2、SuS4、AGPL2、AGPL3、AGPS2、SSI、SSIIa、SSIIc、SSIIIa、SBEI、SBEIIb基因的相对表达量呈极显著正相关关系。【结论】在轻干-湿交替灌溉处理下,水稻弱势粒淀粉合成相关酶活性及其基因表达的增强促进了弱势粒中淀粉的合成与积累,提高灌浆速率和增加粒重;而在重干-湿交替灌溉处理下,弱势粒中上述淀粉合成相关酶活性和基因表达的下降使其灌浆速率和粒重显著降低。 相似文献
3.
4.
Causes of Poor Grain Plumpness of Two-Line Hybrids and Their Relationships to the Contents of Hormones in the Rice Grain 总被引：1，自引：0，他引：1
ZHAO Bu-hong ZHANG Hong-xi ZHU Qing-sen YANG Jian-chang 《中国农业科学(英文版)》2007,6(8):930-940
This study was designed to elucidate the grain filling characteristics and the causes of poor grain plumpness of some two-line hybrid rice combinations and their hormonal mechanism. Six varieties, including three two-line hybrid rice combinations,that show differences in seed-setting and grain filling, were used. And the contents of starch, sucrose, zeatin (Z) + zeatin riboside (ZR), indole-3-acetic acid (IAA), and abscisic acid (ABA), the ethylene evolution rate, activities of sucrose synthase (SuSase) and starch synthase (StSase) in grains, the seed-setting and grain filling rate were investigated. The correlations amongst these were analyzed. The results showed that the poor grain filling of two-line hybrids was mainly attributed to the higher unfilled grain rate and the lower filling degree of inferior grains. During the early and mid grain filling periods, the sucrose content in inferior grains was greater than that in superior grains for the combinations with poor grain filling, indicating that the substrate concentration was not the principal factor for their slow grain filling and poor grain plumpness of the inferior grains of two-line hybrids. Z + ZR, IAA, and ABA in superior grains were obviously greater than those in inferior grains at early grain filling stage. The maximum and mean contents of Z + ZR, IAA, and ABA were positively very significantly correlated with the maximum and mean grain-filling rate, filling degree, and gram weight.The evolution rate of ethylene was greater in inferior grains than in superior grains and greater for the combinations with poor grain plumpness than those with good grain plumpness at the early or mid filling stages. The evolution rate of ethylene was negatively and significantly correlated with the grain filling rate, the grain filling degree, and the grain weight.Spraying ethephon (ethylene-releasing agent) at the early grain filling stage increased the evolution rate of ethylene,reduced the ABA content and activities of SuSase and StSase, and decreased the grain filling degree and the grain weight.The results were reversed when cobatous nitrate (an inhibitor of ethylene synthesis) was applied. The results suggested that the hormones and their balance play a role in the regulation of grain filling and enzymatic activities, and the poor grain filling is attributed to the low contents of Z + ZR, IAA, and ABA, and the high evolution rate of ethylene in the inferior grains of some two-line hybrid rice combinations. The results suggested that hormones play important roles in the grain filling of some two-line hybrid rice combinations, and their filling degree can be improved by regulating the hormonal contents. 相似文献
5.
为明确高产氮高效型籼稻品种的籽粒灌浆特性及其与产量和氮素利用的关系，选用高产氮高效型（HYHNE）、高产氮中效型（HYMNE）和低产氮低效型（LYLNE）杂交籼稻品种，在相应最适氮肥水平下，研究3种类型水稻品种籽粒灌浆特性差异及其与产量和氮利用效率的关系。结果表明，籽粒灌浆特性在不同类型品种间和不同粒位间均存在较大差异。强势粒的最大灌浆速率(GRmax)、达到最大灌浆速率时的米粒重(Wmax)和平均灌浆速率(GRmean)均表现为HYHNE>HYMNE>LYLNE，起始生长势(R0)、活跃灌浆期(D)和有效灌浆时间(T99)均表现为HYHNELYLNE>HYMNE， R0、D和T99均表现为HYHNE相似文献
6.
为明确高产氮高效型籼稻品种的籽粒灌浆特性及其与产量和氮素利用的关系，选用高产氮高效型（HYHNE）、高产氮中效型（HYMNE）和低产氮低效型（LYLNE）杂交籼稻品种，在相应最适氮肥水平下，研究3种类型水稻品种籽粒灌浆特性差异及其与产量和氮利用效率的关系。结果表明，籽粒灌浆特性在不同类型品种间和不同粒位间均存在较大差异。强势粒的最大灌浆速率(GRmax)、达到最大灌浆速率时的米粒重(Wmax)和平均灌浆速率(GRmean)均表现为HYHNE>HYMNE>LYLNE，起始生长势(R0)、活跃灌浆期(D)和有效灌浆时间(T99)均表现为HYHNELYLNE>HYMNE， R0、D和T99均表现为HYHNE相似文献
7.
Kai Liu Yuxiu Ye Cheng Tang Zhiqin Wang Jianchang Yang 《Frontiers of Agriculture in China》2008,2(2):172-180
The objectives of this study were to investigate ethylene and 1-aminocylopropane-1-carboxylic acid (ACC) in rice grains and
root bleeding sap during the grain filling period and their relationship to the grain filling rate. Two high lodging-resistant
rice (Oryza sativa L.) cultivars were grown in pots or tanks. Three treatments, including well watered (WW), moderate soil-drying (MD) and severe
soil-drying (SD), were conducted from 9 days of post-anthesis until maturity. The effects of chemical regulators on the concentrations
of ethylene and ACC in the grains were also studied. The results show that MD significantly increased the grainfilling rate
and grain weight, whereas SD significantly reduced the grain-filling rate and grain weight. Concentrations of ethylene and
ACC in the grains were very high at the early grain filling stage and then sharply decreased during the linear period of grain
growth. MD reduced the ACC concentrations and ethylene evolution rate, whereas SD remarkably increased the ACC concentrations
and ethylene evolution rate. Both the ethylene evolution rate in rice grains and the ACC concentrations in the root-bleeding
sap were significantly and positively correlated with the ACC concentrations in rice grains. The ethylene evolution rate was
significantly and negatively correlated with the grain-filling rate. The application of amino-ethoxyvinylglycine (AVG), an
inhibitor of ethylene synthesis, at 9–13 days of postanthesis significantly reduced the ACC concentrations and ethylene evolution
rate of grains, but significantly enhanced the activities of sucrose synthase, ADP glucose pyrophosphorylase and soluble starch
synthase. The results were reversed when ethephon, an ethylenereleasing agent, was applied. The results suggest that moderate
soil drying during the grain-filling period in rice could inhibit the production of ethylene and ACC and therefore accelerate
grain filling and increase grain weight.
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Translated from Acta Agronomica Sinica, 2007, 33(4): 539–546 [译自: 作物学报] 相似文献
8.
两系杂交稻籽粒充实不良的成因及其与激素含量的关系 总被引：10，自引：0，他引：10
【目的】阐明两系杂交稻籽粒充实特征及籽粒充实不良的成因与激素机理。【方法】采用结实特性差异明显的两系杂交稻为材料，测定籽粒中蔗糖和淀粉含量、玉米素+玉米素核苷（Z+ZR）、吲哚-3-乙酸（IAA）和脱落酸（ABA）含量、乙烯释放速率、蔗糖合成酶（SuSase）和淀粉合成酶（StSase）活性以及籽粒灌浆充实指标，并进行相关分析。【结果】表明两系杂交稻结实率低，主要归咎于弱势粒的秕粒率高、充实度差。籽粒充实度差的组合，灌浆前、中期弱势粒中蔗糖含量高于强势粒，表明基质浓度不是两系杂交稻弱势粒灌浆速率慢和籽粒充实度差的主要限制因子。灌浆前期强势粒中的Z+ZR、IAA和ABA含量明显高于弱势粒，Z+ZR、IAA和ABA的最高含量和平均含量与籽粒最大灌浆速率、平均灌浆速率、谷粒充实度和粒重均呈极显著的正相关。灌浆前、中期弱势粒中的乙烯释放速率明显高于强势粒，籽粒充实度差的组合高于籽粒充实度好的组合，乙烯的释放速率与灌浆速率、谷粒充实度和粒重均呈极显著的负相关。在灌浆初期喷施乙烯合成促进剂（乙烯利），弱势粒的乙烯释放速率增加，ABA含量减少，SuSase和StSase活性降低，谷粒充实度和粒重下降；喷施乙烯合成的抑制剂（硝酸钴），结果则相反。表明籽粒中激素含量及其平衡对籽粒灌浆和酶的活性起调控作用，部分两系杂交稻籽粒充实不良与其弱势粒中Z+ZR、IAA和ABA含量低、乙烯浓度高有密切关系。【结论】激素对两系杂交稻籽粒充实起重要作用，通过调控激素含量，可以提高籽粒充实。 相似文献
9.
杂交水稻籽粒灌浆特性研究 总被引：2，自引：0，他引：2
对1979年杂交水稻汕优3号、四优2号和1985年威优64分期播种的有关数据,采用相关,非线性回归和通径分析杂交水稻的籽粒灌浆特性及其与气候条件的关系。结果表明:1、杂交水稻的弱势粒率较常规稻高,群体籽粒具有明显的二次灌浆高峰。汕优3号的两次高峰分别于开花后第12天和30天。2、杂交水稻自开花至完熟可分为5个时期。其中汕优3号开花后0～5天灌浆缓慢,需要足光和高温。在19～30℃内,灌浆速度与温度成正相关。6～15天以日均温27.28℃、每天日照6.5小时、相对湿度75％为最适。16天至完熟期以日均温22.32℃、相对湿度70～80％为最适。开花后6～10天或16～20天最高温>35℃,对灌浆不利,秕谷率高,减产。3、环境不适或后期叶片早衰,杂交水稻只有一次灌浆高峰,且结实率和粒重均低,减产。故后期田间管理很重要。 相似文献
10.
淀粉合成相关酶活性变化及其与籽粒灌浆和稻米品质的关系 总被引：1，自引：0，他引：1
以弯穗型水稻品种辽138、北方大穗型新株形水稻辽263和杂交稻9158为材料,研究灌浆勰间强弱势粒的灌浆动态、ADP葡萄糖焦磷酸化酶、可溶性淀粉合成酶和Q酶的活性变化及其与籽粒灌浆及与稻米品质之间的关系。结果表明：三种酶的活性达到峰值的时间不同,活性也不同：在各品种强势粒间,酶的活性差异不明显,而在弱势粒间则差异显著：三种酶的活性与籽粒最大灌浆速率和籽粒平均褪浆速率均呈极显著正相关。在整个籽粒发育期间,酶活性对整米率影响最大,其次是胶稠度和直链淀粉,对糙米率和精米率影响最小,没有达到显著相关水平。 相似文献
11.
以扬稻6号和武育粳3号为供试材料,研究了结实期-40kPa低土壤水势对水稻强、弱势粒灌浆特征和主要米质性状的影响,并分析了强弱势粒灌浆特征与稻米垩白之间的关系。结果表明:结实期低土水势对强弱势粒米质主要性状、米粉RVA谱、籽粒灌浆特征和物质的积累有着显著的影响,而且强弱势粒间存在明显的差异。低土水势下,强势粒的起始灌浆势R0增加,而弱势粒R0减小;强弱势粒达到最大灌浆速率的时间Tmax提前,活跃生长期缩短。水分胁迫下弱势粒中蔗糖、可溶性糖含量明显偏高,而淀粉积累明显缓慢。这表明低土水势下强势粒灌浆过快,弱势粒又易丧失对灌浆基质的转化能力,这种籽粒灌浆进程的异常和灌浆物质的分配变化,易形成垩白。低土水势下,强弱势粒米粒的整精米率降低,粗蛋白含量显著增加,米粉的RVA谱特征值发生明显的变化,米饭的食味变差,导致米质变劣。 相似文献
12.
成都平原两熟区籼粳稻品种籽粒灌浆特性 总被引：5，自引：1，他引：4
【目的】研究成都平原两熟区籼、粳稻品种籽粒灌浆特性及产量形成的差异,为成都平原种植粳稻提供依据。【方法】以籼稻品种辐优838、泸优578及粳稻品种辽星15、辽星19为材料进行田间试验,利用Richards方程对不同品种强、弱势粒的灌浆过程进行比较,进而分析不同品种灌浆特性与抽穗后物质积累和转运及产量形成的关系。【结果】粳稻品种中辽星19不仅库容量大,结实率也高,其产量显著高于辽星15,且与籼稻品种辐优838、泸优578相当。籼、粳稻稻品种籽粒灌浆类型分别为强、弱势粒同步灌浆型和异步灌浆型,并且穗型大小对籼、粳稻灌浆结实的影响也存在差异。辽星19抽穗后干物质转运能力更接近当地的籼稻品种,有利于籽粒灌浆的启动;其每穗粒数虽显著高于辽星15,但弱势粒的灌浆速度并未降低,且达到灌浆峰值后下降减缓,灌浆时间也有所延长,最终结实率得到显著提高。【结论】粳稻品种辽星19每穗粒数虽多,但其抽穗后干物质转运能力得到加强,籽粒灌浆得到改善,仍能实现较高的结实率,因此在成都平原仍表现出较好的产量潜力。 相似文献
13.
灌浆期低温对离体培养玉米强弱势粒发育的影响 总被引：1，自引：0，他引：1
【目的】通过对玉米灌浆过程中籽粒干物质、淀粉的积累,籽粒内源激素含量及淀粉积累相关酶活性的研究,揭示低温对灌浆过程中玉米强、弱势籽粒灌浆生理过程的影响规律,为生产上抗御低温冷害提供理论参考。【方法】选用郑单958为试验品种,采用玉米籽粒离体培养的方式,将大田人工授粉后3 d的玉米果穗按照弱势粒和强势粒进行取样,无菌环境接种到人工培养基培养,低温处理和对照分别设置培养平均温度为16℃及25℃。自授粉后每10 d取样一次,分别测定灌浆过程中玉米强、弱势粒干物质积累量、内源激素、籽粒淀粉含量及淀粉积累相关酶活性。【结果】低温胁迫下强、弱势粒灌浆后期粒重分别比对照低47.58%、50.95%,强、弱势粒灌浆高峰期的平均灌浆速率较对照分别显著降低55.39%、54.72%。低温胁迫下玉米籽粒灌浆速率前期提升和后期减小的速度明显减缓,活跃灌浆时间延长5-7 d。授粉后10 d低温处理显著降低玉米强、弱势粒生长素（IAA）、玉米素（ZR）和脱落酸（ABA）含量,显著提高玉米籽粒赤霉素（GA3）的含量。授粉后30 d低温处理显著降低了弱势粒的IAA、ZR含量,增加了强势粒的ABA含量。低温胁迫显著减弱了灌浆前期和灌浆中期的可溶性酸性转化酶（SAI）、蔗糖合酶（SS）、淀粉合酶（SSS）及ADPG焦磷酸化酶（APGase）的活性,低温下弱势粒SAI活性降幅大于强势粒,对SS、SSS及APGase活性的降低幅度表现为强势粒大于弱势粒,导致玉米籽粒淀粉含量降低。【结论】受低温胁迫影响,灌浆前期玉米籽粒的IAA、ZR、ABA含量减少,GA3含量增加,SAI活性降低,导致籽粒库容量减少,库活性不足。在灌浆中期,低温降低SS活性,造成淀粉合成底物供应不足,影响淀粉的合成,降低籽粒淀粉含量。低温处理降低玉米强、弱势粒的灌浆速率,导致籽粒干物质积累减少。低温对玉米强弱、势粒的灌浆过程都造成较大的影响,且对弱势粒的影响大于强势粒。 相似文献
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[目的]为了明确温度对两系杂交早稻灌浆成熟期籽粒淀粉合成代谢的影响。[方法]以两系杂交早稻株两优611和陆两优996为材料,研究了温度对两系杂交早稻株两优611和陆两优996灌浆期籽粒中直链淀粉积累、ADPG焦磷酸化酶（ADPG-PPase）和可溶性淀粉合成酶（SSS）活性的影响。[结果]高温条件下株两优611和株两优996灌浆前期籽粒中ADPG-PPase和SSS活性高,直链淀粉积累快,粒重增长快,持续时间短,抽穗10 d后ADPG-PPase和SSS活性迅速下降,抽穗16 d后淀粉积累趋于停止。适温条件下籽粒中AD-PG-PPase和SSS活性变化缓慢,抽穗13 d后达到其活性高峰值,直链淀粉积累慢,持续时间长,抽穗19 d后籽粒中仍有少量淀粉积累,粒重较高温条件下高。[结论]2个不同类型品种中适合作米粉原料的陆两优996在高温条件下籽粒中直链淀粉含量较适温条件下高,高温有助于高直链淀粉含量品种陆两优996籽粒直链淀粉的积累。 相似文献
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Response of grain-filling rate and grain quality of mid-season indica rice to nitrogen application 
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下载免费PDF全文 Jing ZHANG Yan-yan ZHANG Ning-yuan SONG Qiu-li CHEN Hong-zheng SUN Ting PENG Song HUANG Quan-zhi ZHAO 《农业科学学报》2021,20(6):1465-1473
Nitrogen is one of the important factors for high yield of rice. Apart from high yield, high quality has become the current urgent demand for rice production. Grain-filling stage is crucial for rice yield and quality formation. However, the effect of nitrogen on grain-filling characteristics and the relationship of grain-filling characteristics and rice quality of mid-season indica rice were still unclear. A field experiment was carried out to ascertain the critical grain-filling characteristics that contribute to rice milling quality, appearance quality and cooking and eating quality under nitrogen applications. The results showed that nitrogen applications prolonged the duration of superior and inferior grain filling. The mean grainfilling rate(G_(mean)) and the maximum grain-filling rate(G_(max)) of the inferior grains were positively correlated with chalky kernel rate, chalkiness, and amylose content. The time reaching the maximum grain-filling rate(T_(max) G) of the inferior grains was positively correlated with brown rice rate, milled rice rate, and head milled rice rate. Chalky kernel rate and chalkiness were negatively correlated with peak paste viscosity and breakdown viscosity. Less amylose content and more crude protein content were detected in nitrogen application of Liangyoupei 9 and Y Liangyou 2 both in 2016 and 2017. According to the correlation analysis, better cooking and eating quality of Y Liangyou 2 which had less amylose content might result from its higher G_(max) and G_(mean) of inferior grain than that of Liangyoupei 9 in the treatments of nitrogen application. These results indicated that the prolonging grain-filling duration and increasing grain weight at the maximum grain-filling rate of inferior grains contributed to the improvement of milling quality, appearance quality, and cooking and eating quality of mid-season indica rice under appropriate nitrogen applications. 相似文献
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水稻结实期不同粒位籽粒相关内源激素含量和关键酶活性的差异及其与品质的关系 总被引：6，自引：2，他引：4
【目的】研究灌浆期水稻穗上不同粒位籽粒内源激素含量和关键酶活性的差异及其与籽粒品质形成的关系。【方法】以中熟籼稻扬稻6号和中熟粳稻扬粳9538为材料,按照一次枝梗数将稻穗分为上、中、下三个部位,以穗中部一、二次枝梗不同粒位籽粒为研究对象。【结果】灌浆前期开花较早的籽粒中玉米素（Z）+玉米素核苷（ZR）、吲哚乙酸（IAA）、脱落酸(ABA)含量以及淀粉合成酶（SSase）、淀粉分支酶（Q酶）活性明显高于同枝梗上开花较迟的籽粒,灌浆后期则相反;籽粒开花越早,其内源激素含量以及酶活性到达最大值的时间越早,峰值也越高。灌浆前期ABA、Z+ZR、IAA含量、ABA/（Z+ZR+IAA）比值以及SSase酶和Q-酶活性与千粒重、直链淀粉累积速率、直链淀粉含量呈显著或极显著正相关,与垩白度呈显著或极显著负相关,灌浆后期则相反;灌浆前期SSase和Q-酶活性与胶稠度呈负相关,中、后期则相反;与粗蛋白含量的相关两品种存在差异,与整精米率相关不显著。【结论】灌浆期水稻穗上不同粒位籽粒内源激素含量与关键酶活性存在差异;不同粒位间籽粒米质差异的形成与籽粒内源激素含量与关键酶活性密切相关。 相似文献
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18.
The changes in grain-filling, starch accumulation and activity of enzymes associated with starch synthesis in two different hybrid rice varieties were analyzed at different N supplying dates (earlier-date-emphasized, mean-date-emphasized and later-date-emphasized). The results showed that the N application of later-date-emphasized could promote grain-filling rate, increase grain weight and amylopectin content. The peak of activity in three enzymes of ADPglusoce pyriphosphorylase (ADPG), starch synthesis enzyme (SSS) and starch branching enzyme (SBE) in grains of two different rice varieties was not changed obviously, but the mean and maximum activity of these three enzymes changed, and the changes of SSS and ADPG were bigger than that of SBE as N supplying date changed. The N application of earlier-date-emphasized increased SSS activity and the N application of later-date-emphasized increased ADPG and SBE activities. The mean SSS activity during whole grain-filling period, and ADPG and SBE activities at middle and late period of grain-filling were significantly or very significantly correlated with grain-filling rate and accumulating rate of amylose and amylopectin. Both of ADPG and SBE played an equal important role in the changes of amylose and amylopectin content. The N application of later-date-emphasized increased amylose and amylopectin accumulating rate. 相似文献
19.
两系杂交稻茎鞘物质运转与籽粒充实特性研究 总被引：3，自引：0，他引：3
选用不同类型的两系杂交稻品种,研究了结实期茎鞘物质运转与籽粒灌浆结实的关系。结果表明,两系杂交稻在抽穗后的净光合速率和干物质积累量明显高于三系杂交稻;茎鞘物质的输出率与结实率、充实率、最大灌浆速率和平均灌浆速率呈显著的正相关;各品种以下部茎鞘物质积累多、转运率高;茎鞘物质转运启动时间早、运转强度大,其转运率高、结实率高、充实度好,表明早期转运对籽粒灌浆充实的重要性;抽穗期提高糖花比,同时在灌浆始期促进茎鞘非结构性碳水化合物向籽粒库运转,有利于激发库的活性,启动和促进更多的籽粒灌浆,减少空秕粒的产生,增加籽粒充实率。 相似文献
20.
为探究高温条件下水稻垩白形成的生理机制,以高垩白性状湘早籼24号(X24)及其来源亲本湘早籼11号(X11,高垩白性状)和湘早籼7号(X7,低垩白性状)为材料进行盆栽试验,在抽穗后第6天移入温室,进行为期15 d的高温处理(27～42℃),以常温处理(23～37℃)作为对照,研究灌浆期高温条件下剑叶净光合速率、籽粒灌浆速率、籽粒直链淀粉含量及淀粉合成相关基因的相对表达量等的变化。结果表明：高温条件下X7、X11和X24的稻米垩白度比常温对照处理的分别增加了2.53、4.82、6.66个百分点;高温造成X11和X24的叶片净光合速率在抽穗后第8、12、16天显著低于常温对照的,而X7的叶片净光合速率在抽穗后第16天反而高于常温对照的;高温条件下水稻在抽穗后第8天灌浆速率加快,并在抽穗后第12天达到最大值,较常温处理的提前了4～8 d;基因相对表达量差异分析表明,X11和X24籽粒淀粉合成相关基因Os SSIIIa、Os AGPSL2和GBSSI在抽穗后第12、16天的表达显著下调,导致籽粒直链淀粉含量降低及垩白度增加。 相似文献