超级杂交稻两优培九剑叶叶鞘叶绿体光化学活性的初步研究

以超级杂交稻两优培九及其父本9311、母本培矮64S和三系杂交稻组合汕优63为研究材料,采用光合膜人工反应体系和32Pi同位素标记等技术,初步研究了超级杂交稻两优培九剑叶叶鞘的光化学活性。结果表明,两优培九剑叶叶鞘及其叶片光系统Ⅰ还原能力的均值分别比汕优63高6.35和15.31 μmol/(mg·h),光系统Ⅱ放氧活性的均值分别高出616和9.89 μmol/(mg·h),且大多数时期达显著或极显著水平;两优培九剑叶叶鞘及其叶片浸出液钙含量均显著或极显著高于汕优63;两优培九剑叶叶鞘及其叶片叶绿体膜上Mg2+ ATPase活性的均值均高于汕优63,大多数时期达显著或极显著水平;两优培九剑叶叶鞘及其叶片循环光合磷酸化活性的均值也均高于汕优63,近一半时期达显著或极显著水平;非循环光合磷酸化活性的均值分别比汕优63高0.25和0.31 μmol/(mg·h),也近一半时期达显著或极显著水平;两优培九剑叶叶鞘及其叶片的光化学活性大多数时期显著或极显著高于亲本,具有平均优势或超亲优势;与叶片相比,剑叶叶鞘完全具有同剑叶一样的光化学活性,两者没有质的区别;两优培九剑叶叶鞘具有较高的光化学活性可能是它具有超高产特性的重要原因之一。     

盛花期高温对两系杂交稻两优培九结实率的影响研究

对两优培九和汕优63在盛花期置于人工气候室36℃高温下处理不同时间的结果表明,在无库源关系限制下,两优培九结实率明显高于汕优63, 表明两优培九具有较强的耐高温能力.然而,当两优培九、汕优63和Ⅱ优7号种植于不同密肥构建的6种库源群体条件下时,两优培九结实率却明显低于汕优63和Ⅱ优7号.对空秕率构成的分析表明,两优培九结实率低主要是由于受精子房中途停止发育所致.     

高产杂交籼稻Ⅱ优129光合碳同化特性的研究

从光能利用率差异的角度探讨了高产杂交籼稻Ⅱ优129和对照汕优63的光合碳同化特性。结果表明：a)Ⅱ优129的光能利用率和产量显著高于汕优63，但其叶面积指数、消光系数及生育期无显著差异，说明光合效率及光合功能期是导致两组合光能利用率差异的主要原因；b)Ⅱ优129剑叶的CO2日同化量、叶源量及单茎CO2同化量均极显著高于汕优63，说明前者的碳同化能力较后者强；c) 提高一个耐光抑制等级即可减少约3％的CO2日同化量的损失，提高品种的耐光抑制等级可进一步提高光能利用率；d)用光合速率高值指数作为衡量叶片一生中光合机构高效运行状态的一个生理指标，有助于揭示光合功能衰退对产量影响的生理机制，提高光合速率高值指数是提高光合效率的一个重要途径。     

不同株型水稻叶倾角群体分布的模拟

 以株型因子为参数,建立了不同株型品种水稻叶倾角分布模型。对该模型进行验证,模拟值与实测值的1∶1回归直线的R2和RMSE分别为0.9472和3.93%。用本模型对3种株型、6个冠层高度和7个生长期的水稻冠层叶倾角分布的模拟结果表明,3种株型水稻叶倾角分布不同,紧凑株型的两优培九叶倾角较大,叶片挺立;松散株型的汕优63叶倾角最小,叶片披垂;中间型两优Y06介于两者中间,与实际观察结果一致。同一品种7个生长期叶倾角分布不同,从分蘖期到孕穗期,冠层叶倾角逐渐变大,叶片逐渐挺立;从孕穗期到成熟期,两优培九叶倾角变化不明显,汕优63和两优Y06则逐渐变小,叶片逐渐披散,其中,汕优63尤为明显。同一品种相同生长期的 6个冠层高度叶倾角分布不同,随着冠层高度增加,3个品种的分层LAI均减小,两优培九叶倾角变化不大,汕优63逐渐增大,两优Y06逐渐减小。试验证明该模型具有良好实用性。     

两系杂交稻组合两优培九和65396的光合形态特征研究

采用分期播种和平行比较方法 ,对两系杂交稻组合两优培九和 65 3 96的光合形态性状进行了研究。与汕优 63相比 ,两优培九和 65 3 96在单株绿叶数达到最大值之前的增长速率基本一致 ,但其后的衰减速率却明显要慢 ,且功能叶较厚、叶角小、叶凹度大 ,光合优势明显。若以叶面积×叶重系数为综合光合特性 ,则 3个组合中 ,65 3 96功能叶的光合优势最佳。     

春玉米超高产群体冠层结构的研究

以紧凑型玉米新品种内单314为材料,通过超高产栽培和普通高产栽培的比较,对超高产玉米的冠层结构和叶片光合特点进行了研究。结果表明:①超高产栽培条件下,内单314最大LAI(叶面积指数)达6.95,其全生育期内LAI维持在6以上的时间在40d以上;全生育期总LAD(光合势)比普通高产群体高74.85万m2/(d·hm2)。②与普通高产玉米相比,超高产玉米群体内个体空间分布更加合理,叶片功能期延长,株型更加紧凑。超高产群体冠层截获的PAR(光合有效辐射)比普通高产群体高25μmol/(m2·s),且超高产群体中散射PAR占入射PAR的比例高于普通高产群体,群体内光分布较为合理,提高了光能利用率。③与普通高产群体相比,超高产栽培条件下玉米叶片的Pn(光合速率)和WUE(水分利用效率)高,而Tr(蒸腾速率)较低,植株穗位及穗位上部叶片的Pn和WUE高于普通高产栽培,而穗位下部叶片无明显差异。     

稻田水分管理方式对水稻光合速率和水分利用效率的影响

以超级杂交稻两优培九和中优6号为材料, 设3个不同水分管理措施,在穗分化期、开花期和花后20 d分别测定叶片光合速率和水分利用率。结果表明:不同水分管理方式影响水稻地上部干物重、叶面积指数、光合速率、蒸腾速率和水分利用效率。水分好气灌溉管理地上部干物重和水分利用效率明显增加;水分低水位管理蒸腾速率、地上部干物重和叶片水分利用效率下降。淹水灌溉地上部干物重、叶面积指数、叶片光合速率和水分利用率较低。因此,水稻好气灌溉有利于光合物质积累,显著增产和提高水分利用效率。试验还表明这3种水分管理对稻米蛋白质含量的影响不显著。     

强化栽培下水稻穗分化期叶片光合速率与水分利用率的研究

 用超级杂交稻两优培九、Ⅱ优7954和国稻1号作为研究材料，比较SRI水稻穗分化期不同移栽密度叶片光合速率和水分利用率。结果表明，SRI水稻稀植后能保持一定的叶面积指数，随着移栽密度从1.95×105丛/hm2下降到0.75×105丛/hm2，群体透光率增加，各叶位(第9叶至第13叶)叶片的光合速率和水分利用率明显提高，蒸腾速率降低，抽穗整齐度下降，第9叶和第10叶的光合速率和水分利用率提高的幅度较大。在试验条件下，水稻强化栽培的产量在移栽密度为165×105丛/hm2 时最高。     

超高产杂交水稻培矮64S/E32和两优培九剑叶对高温的响应

 以汕优63为对照，研究了新育成的两个超级杂交水稻组合培矮64S/E32和两优培九的高温耐受特性。结果表明高温引起了光合效率降低，加重了光合光抑制。光化学、光合电子传递最适温度在28℃左右，光合碳同化的最适温度在35～40℃。高温下通过PSⅡ线性电子传递的能力几乎丧失（下降96.7%～100%），而PSⅡ光化学效率下降较少（8.8%～210%）,暗示PSⅡ光合线性电子传递过程比光化学能转化对高温更敏感。超级杂交稻比对照汕优63更耐高温，其机理可能如下：一是因为超级稻在高温时有更迅速的类胡萝卜素积累，增加其抗氧化能力，减少了因过剩激发能积累引起活性氧产生、积累并伤害光合细胞；二是因为超级稻高温下有高效的叶黄素循环热耗散途径可以耗散过量的激发能； 三是因为超级稻在高温下有稳定的光合功能和较强的光合效率，较高的热稳定蛋白含量。     

两个水稻亚种间新组合高产形态机理研究

以培矮64S/R 292,Y 58S/R 292为材料,以丰源优299为对照,研究了水稻倒3叶叶长、叶宽、叶片披垂度、叶片卷曲程度等主要形态指标及其与产量的相关性。结果表明：培矮64S/R 292,Y 58S/R 292叶片所处空间层高,叶片卷曲程度大,叶片挺直,不遮阴下部叶片,有效光合面积大,光合态势好。与产量相关性分析表明,倒3叶叶长、叶宽、叶片卷曲度与产量显著正相关,叶片披垂度与产量显著负相关。     

Simulation on Distribution of Photosynthetically Active Radiation in Canopy and Optimum Leaf Rolling Index in Rice with Rolling Leaves

By replacing leaf area index (LAI) with effective leaf area index (ELAI) through introduction of leaf rolling index (LRI), the distributions of photosynthetically active radiation (PAR) in the canopies of three hybrid rice combinations, Liangyou E32 with high LRI, Liangyoupeijiu with moderate LRI and Shanyou 63 with non-rolling leaves (normal), were simulated. The model based on ELAI could predict more accurately than that based on LAI. The PAR interception, conversion and utilization efficiency in the three combinations were studied to evaluate their optimal LRI and LAI. The PAR utilization efficiency of Liangyou E32 was lower due to excessive rolling leaves and less ELAI, and that of Shanyou 63 was also lower because of the faulty PAR interception and lower photosynthetic rate and saturation point at lower layer in canopy. Compared with the above two combinations, Liangyoupeijiu showed more appropriate distribution of PAR interception and conversion efficiency in canopy, and higher PAR utilization efficiency. The optimal LRI and LAI for Liangyoupeijiu were 0.11 and 7.6, respectively, which were close to the observed value, 0.11 and 7.9, respectively. However, the optimum LAI was 9.8 for Liangyou E32 and 6.2 for Shanyou 63, larger or smaller than those under the current plant density, which led to lower efficiency of PAR utilization. Besides, the optimum LRI for Liangyou E32 and Shanyou 63 were 0.12 and 0.08, respectively, which were close to the actual LRI for Liangyoupeijiu (0.11).     

Simulation of Canopy Leaf Inclination Angle in Rice

A leaf inclination angle distribution model, which is applicable to simulate leaf inclination angle distribution in six heights of layered canopy at different growth stages, was established by component factors affecting plant type in rice. The accuracy of the simulation results was validated by measured values from a field experiment. The coefficient of determination （R2） and the root mean square error （RMSE） between the simulated and measured values were 0.9472 and 3.93%, respectively. The simulation results showed that the distribution of leaf inclination angles differed among the three plant types. The leaf inclination angles were larger in the compact variety Liangyoupeijiu with erect leaves than in the loose variety Shanyou 63 with droopy leaves and the intermediate variety Liangyou Y06. The leaf inclination angles were distributed in the lower range in Shanyou 63, which matched up with field measurements. The distribution of leaf inclination angles in the same variety changed throughout the seven growth stages. The leaf inclination angles enlarged gradually from transplanting to booting. During the post-booting period, the leaf inclination angle increased in Shanyou 63 and Liangyou Y06, but changed little in Liangyoupeijiu. At every growth stage of each variety, canopy leaf inclination angle distribution on the six heights of canopy layers was variable. As canopy height increased, the layered leaf area index （LAI） decreased in all the three plant types. However, while the leaf inclination angles showed little change in Liangyoupeijiu, they became larger in Shanyou 63 but smaller in Liangyou Y06. The simulation results used in the constructed model were very similar to the actual measurement values. The model provides a method for estimating canopy leaf inclination angle distribution in rice production.     

两系杂交稻组合两优培九和65396的光合形态特征研究

采用分期播种和平行比较方法，对两系杂交稻组合两优培九和 ６５３９６ 的光合形态性状进行了研究。与汕优 ６３ 相比，两优培九和 ６５３９６ 在单株绿叶数达到最大值之前的增长速率基本一致，但其后的衰减速率却明显要慢，且功能叶较厚、叶角小、叶凹度大，光合优势明显。若以叶面积×叶重系数为综合光合特性，则 ３ 个组合中，６５３９６ 功能叶的光合优势最佳。     

三个C两优杂交稻组合的株型及干物质生产特性

 以汕优63为对照,对3个C两优杂交稻组合的株型及干物质生产特性进行了研究。与汕优63相比,C两优杂交稻组合上3叶叶型较狭长,叶片着生角度小,总叶面积较大;齐穗期上3叶净光合速率和叶绿素含量较高,根系活力较强;基部节间较粗、较短,茎秆的抗倒性强, 中部节间较长,穗下节间占总秆长的42.77%;抽穗后干物质积累速率快,增量大,且茎鞘叶中的干物质向籽粒运转量多,对籽粒的贡献率高。C两优杂交稻抽穗后茎叶干物质输出量和干物质积累量与稻谷产量分别呈显著和极显著正相关。C两优杂交稻组合较理想的株型和中后期强大的干物质生产和转运优势是其高产的重要原因。     

两系杂交稻扬两优6号源库特征与结实特性的分析

以两系杂交稻扬两优6号和两优培九及三系杂交稻汕优63为材料,研究了源、库、流特征及其与籽粒充实的关系。 扬两优6号和汕优63的结实率、籽粒充实度和产量明显高于两优培九;扬两优6号和汕优63茎鞘物质输出率和转换率显著高于两优培九;扬两优6号和汕优63籽粒中蔗糖合成酶、腺苷二磷酸葡萄糖焦磷酸化酶、淀粉合成酶和淀粉分支酶的活性显著高于两优培九,且上述各酶的活性与籽粒最大灌浆速率、平均灌浆速率、谷粒充实度和粒重呈极显著的正相关;扬两优6号和汕优63的单位维管束和韧皮部的颖花负荷、现实产量负荷、总库容负荷显著小于两优培九,且负荷越大的组合结实率就越低,充实度也就越差。扬两优6号单位面积韧皮部的物质转运速率显著高于两优培九和汕优63。表明扬两优6号具有源足、库强、流畅的特点,这是它结实率高和籽粒充实度好的生理基础。     

籼粳亚种组合干物质累积效率与光合特性的关系

从光合特性研究表明：亚种间杂交稻的高干物质累积效率，不是由于单叶光合速率的提高，而是因为叶面积指数增大所致．光合系统发达，利用弱光能力较强，是其叶面积指数增大的生理基础。亚种杂交稻每粒谷子所占叶而积同汕优６３十分接近，但每朵颖花占有的叶面积则比汕优６３低１４．８％。     

Physiological and Biochemical Characteristics in Flag Leaves of the C Liangyou Series of Hybrid Rice Combinations at Late Growth Stages

The contents of chlorophyll,soluble sugars,soluble proteins and thiobarbituric acid reaction substance(TBARS),chlorophyll fluorescence parameters,net photosynthetic rate as well as the activities of superoxide dismutase(SOD)and peroxidase(POD)of flag leaves at the late growth stages were studied by using C Liangyou series of hybrid rice combinitions as material and Shanyou 63 as control.The C Liangyou series of hybrid rice combinations used in the experiment included C Liangyou 396,C Liangyou 87,C Liangyou 755 and C Liangyou 34,which all used C815S as male sterile line.The contents of chlorophyll,soluble sugars and soluble proteins in flag leaves of the C Liangyou series combinations at the late growth stages were higher than those of the control,whereas the TBARS content was lower than that of the control.The activities of SOD and POD were significantly higher than those of the control on the 7th day after heading,and then decreased slowly.ΦPSIIvalue and qP value of flag leaves decreased at the late growth stages,and these two parameters in flag leaves of the C Liangyou series combinations were higher than those of the control,while the qN value increased at the late growth stages and was lower than that of the control.The net photosynthetic rate of flag leaves at the late growth stage was higher compared with the control.These results suggest that slow senescence and strong photosynthetic capability in flag leaves at the late growth stages are the physiological basis of the C Liangyou series combinations.