水稻株型因子对冠层结构和光分布的影响与模拟

 以3个具有代表性株型的杂交稻为材料,并结合上位2叶伸长期施用氮肥以调节上部叶片的形态,于齐穗期、齐穗后10 d、齐穗后25 d平行测定了株型元素 分层叶面积 冠层光分布。用试验数据验证了由水稻株型因子计算分层叶面积的解析模型,并用该模型分析了3个材料株型因子对冠层结构的影响。进一步根据作物群体光分布模型,验证了分层叶面积与冠层内光分布的数值关系,并用该模型分析了3个材料株型因子对冠层内辐射分布的影响。实现了由水稻株型因子估算冠层结构和冠层内光分布的方法。     

卷叶水稻的光分布模拟及适宜叶面卷曲度分析

 以叶面高度卷曲的水稻组合两优E32、中等卷曲组合两优培九和不卷曲组合汕优63为材料,引入叶面卷曲度因子,用有效叶面积指数代替传统的叶面积指数（LAI）,模拟水稻冠层内的辐射传输,比较了不同叶面卷曲度因子材料的光合有效辐射截获率、转化率和利用率,探讨了不同材料的最适叶面卷曲度及最佳群体密度。结果表明,有效叶面积指数比传统的叶面积指数能更准确地预测冠层内光合有效辐射的分布。两优E32叶片过度卷曲,有效叶面积指数偏小,光合有效辐射利用率不高;而汕优63叶片平展且披散,下层叶片长期受光条件不良,光合能力弱,光合有效辐射利用率也不高。相比之下,两优培九的光合有效辐射截获率、转换率分布较为合理,光合有效辐射的利用率也较高,最适LAI为7.6,与常规栽培条件下的群体密度（LAI=7.9）接近。两优E32和汕优63的最适LAI分别为9.8和6.2,而常规栽培条件下的群体密度过小或过大,导致光合有效辐射利用率不高。利用孕穗期至齐穗期有效辐射利用率的实测值,通过输入不同的叶面卷曲度因子,得到两优E32、两优培九和汕优63的最佳叶面卷曲度因子分别为0.12、0.11和0.08,均非常接近两优培九的实际叶面卷曲度因子（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.     

超高产杂交稻两优培九齐穗期株型的区域差异及对冠层结构的影响

 以超高产杂交稻两优培九为材料,于2006年和2007年在江苏扬州、福建尤溪、湖北武汉、云南涛源、四川江油、广东广州、海南海口、广西南宁共8个生态试验点进行齐穗期株型观测,分析了各个生态点株型特征,并根据相应气象资料建立了两优培九齐穗期株型的环境模型。依据1951-2005年的气候资料模拟,比较了华南双季稻区、长江中下游稻区、四川盆地稻区和云南河谷单季籼稻区齐穗期两优培九株型的特征与差异,分析了4个稻区叶片形态差异对植冠层结构的影响。提出植冠层有效厚度和叶面积密度可以作为水稻“株型产量”载体的2个群体结构指标。     

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).     

水稻叶龄与叶面积指数动态的模拟研究

 依据不同类型品种的播期试验和氮肥试验结果,建立了水稻叶龄与叶面积指数(LAI)的模拟模型。叶龄模型采用幂函数描述叶片出生与播后累积热时间(TTS)的关系,TTS的计算定量了温度与出叶速率之间的非线性关系。叶面积指数模拟包括两个阶段:在指数生长阶段,LAI随播后累积生长度日(GDD)呈指数式增长,同时受到氮素营养水平调节;当LAI≥1.6时进入非指数生长阶段,采用比叶面积法模拟,LAI是比叶面积与绿叶干物质量的乘积。绿叶干物质量是绿叶分配指数与地上部干物质量的乘积,比叶面积(SLA)为GDD的函数,同时考虑植株氮素营养因子对SLA的影响。利用生态条件和栽培条件差异较大的试验资料对模型进行了验证。结果表明,模型能较好地模拟不同条件下叶片的出生动态和LAI变化动态,表现出较强的适用性,具有参数少、易确定、简便实用的特点。     

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。     

北方杂交粳稻株型与稻米品质性状的关系

 为明确株型与稻米品质的关系,将株型育种与优质育种有机结合,运用典型相关分析及典型冗余分析等方法,以10个不育系与10个恢复系配组的100个杂交粳稻为材料,研究了株型与稻米品质间的关系。结果表明株型与部分米质性状之间关系密切;倒2叶基角、单穗重在株型性状体系中起重要作用;直链淀粉含量及粒长在米质性状体系中起重要作用。倒2叶基角、株高和单穗重对米质性状影响较大;直链淀粉含量、糙米率和透明度受株型性状影响较大。选择指数模型表明米质较优的北方杂交粳稻的株型为：剑叶、倒2叶较宽,倒3叶较短且窄,株高偏矮,秆长较短,穗子较长,穗数较多且单穗重较轻。     

籼型杂交稻恢复系动态株型与光能利用率评价

[目的]理想株型是水稻高产稳产的前提.本研究拟对不同年代育成的籼型三系杂交稻恢复系动态株型与光能利用效率进行综合评价,探讨恢复系光能高效利用的理想动态株型特征,为提高光能高效利用的高产稳产杂交稻育种效率提供理论依据.[方法]以明恢63、明恢82、蜀恢527、广恢998、广恢122、广恢128、广恢308和桂99等8个大...     

水稻不同叶位层物理结构与冠层反射光谱的定量研究

 研究了不同土壤水分、施氮条件下水稻冠层反射光谱与冠层生长特征（叶面积指数、叶片干质量和鲜质量）的量化关系。结果表明，不同层次叶面积指数、叶片鲜质量和叶片干质量与冠层光谱的相关性大小均为：L12345>L1234>L123>L12>L1，而顶部5张叶片的面积和生物量（干、鲜质量）对冠层特征反射光谱的贡献大小顺序为：L2>L1>L3>L4>L5，顶部2张叶片对冠层光谱作用最大。发现比值指数R(760,710) 与水稻叶面积指数呈极显著线性相关；而比值指数R(1650,1100) 与水稻地上部鲜质量和干质量均呈极显著幂函数相关关系。因此，比值指数R(760,710) 和R(1650,1100) 可分别用来定量反演水稻叶面积信息和地上部生物量信息。     

不同株型粳稻品种的冠层特征和物质生产关系的研究

 对不同株型粳稻品种的冠层特征与群体物质生产和产量的关系进行了研究。结果表明，品种的株型不同，对肥力的反应不同，冠层发展动态和干物质生产速度亦有明显差异．表现为随着肥力水平的提高，不同株型品种同抽穗前叶面积增长速度的差异减小，抽穗后叶面积衰减速度的差异增大。抽穗期的LAI与抽穗后群体干物质生产速度和产量之间呈二次曲线回归关系，获得最高产量的最适LAI与获得最大干物质生产速度的最适LAI基本上是一致的，抽穗后群体干物质生产速度与产量之间亦呈现出极显著的正相关。     

水稻冠层光分布模拟与应用

 综合已有作物模型的优点,构建了水稻冠层光分布模型,并进一步与原有光合作用和干物质生产模型相耦合,构建了水稻光合生产模型。新模型将水稻冠层按叶面积指数划分为5层,各层次水平面上的太阳辐射强度按Monsi和Saeki的指数模型进行分布;模型利用日照百分率资料推算直接辐射与散射辐射,并考虑了光合有效辐射的日变化、冠层结构和太阳位置对直接辐射消光系数的影响。利用独立的水稻田间试验资料,对主要生育期冠层内的光分布进行了初步验证,结果表明模拟值与观测值之间具有较好的一致性。最后,将基于冠层光分布模型与原有光合生产模型进行了比较,预测水稻干物质积累量的根均方差分别为0.74 t/hm2和1.26 t/hm2,建立的基于冠层光分布模型的预测性较好。研究结果将为水稻生长模型的改进完善以及生产管理调控与品种数字化设计奠定基础。     

水稻株型相关基因的定位与克隆研究进展

水稻株型相关性状包括分蘖数、分蘖夹角、株高及穗部性状。株型相关性状都是重要的农艺性状,是水稻产量因素的重要组成部分。株型形成涉及到一系列基因的表达和表达产物行使功能,因此对这些基因的挖掘和功能分析具有重要意义。目前,虽尚未完全了解控制株型相关性状的基因及其功能,但也已取得了日新月异的进展。本文针对各个株型相关性状,综述了已鉴定的基因及其功能特点,以为分子育种运用及进一步遗传生理研究作理论基础。     

水稻理想株型育种研究进展

理想株型与杂种优势利用相结合是实现水稻单产突破的重要途径之一。综述了理想株型的概念、株型构成因子及其相互关系、国内外株型育种的主要理论及存在的问题。提出了动态理想型的株型观点和水稻动态理想型的主要塑造途径,对水稻动态理想型育种进行了展望。     

早籼稻品种遗传改良进程中株型的演变特征

 以不同年代育成的28个代表性早籼稻品种为材料,在同一生态条件下种植,系统研究了叶型、茎型、穗型若干株型性状的演变特征。结果表明,早籼稻品种改良进程中,上部3片功能叶均变短、变厚、变直、变挺;各节间变短、变粗,节间密度变大,尤以基部节间和穗下节间最为显著,而单位鞘重变化不显著;每穗粒数、二次枝梗数、着粒密度均变大。据此认为,早籼稻叶型改良应在保持现有叶片曲率的前提下增加叶长;茎型改良应增加基部节间的粗度和穗下节间的长度;穗型改良应增加每穗粒数和枝梗数。     

温敏核不育水稻植株温度的变化规律及与环境关系的模型

以温敏核不育水稻培矮64S为材料,采用10～15 cm水层灌溉处理和无水层对照,对植株温度及其与植株冠层小气候和灌溉水因子的关系作了分析。水稻植株温度与150 cm大气温度在数值和相位上均存在一定差异。8:00～20:00植株温度均明显低于大气温度,21:00～次日7:00植株温度与大气温度基本相同;日最高植株温度出现在13:00,比最高大气温度提前1 h,但日最低植株温度和最低大气温度均出现在6:00;植株温度的平均日较差比气温小。在同一高度上相比,晴天6:00～13:00植株温度比空气温度高,而且提前1 h升温,18:00～次日6:00则两者逐渐趋同或植株温度稍低;而在阴天,植株温度则全天一直高于空气温度,最高温度出现的时间也相同。植株温度白天的变化主要受太阳辐射的影响,天空状况（云量或日照时数）和风速都通过对辐射强度的调节和热量的交换而产生作用。植株温度夜间的变化主要受灌溉水的影响。在本试验条件下,日平均气温（Ta）29.6℃是灌溉水提高或降低植株温度的临界温度值,当Ta＞29.6℃时,灌溉水具有降低植株温度的作用,反之,灌溉水具有提高植株温度的作用。植株温度与水 气温差符合二次曲线关系。植株冠层在白天吸收或反射太阳辐射,夜间则阻挡热量散失,对调节植株温度具有明显的缓冲效应。通过相关分析和回归拟合,建立了两个可供实用的水稻植株温度的环境模型。     

Studies on Plant Population and Stand Establishment Techniques for Increasing Productivity of Rice in Dera Ismail Khan, Pakistan

Rice production in Pakistan is constraint by many factors pertaining to prevalent planting techniques. A research on the feasibility of new planting techniques (direct seeding on flat, transplanting on flat, direct seeding on ridges, transplanting on ridges and parachute planting) in transplanted and direct wet-seeded rice was undertaken at Dera Ismail Khan region of Pakistan’s North West Frontier Province during 2002 and 2003. Among the planting techniques, the best performance for the yield formation and economic evaluation was noted for transplanting on flat during both years. Chinese parachute planting technology also showed very promising results in most of the parameters. Direct seeding on ridges could not excel transplanting on flat and parachute planting during both cropping seasons. The findings concluded the feasibility of parachute planting technology along with traditional rice transplanting on flat over all other planting techniques being practiced in the area.     

Relationship Between Plant Type and Grain Quality of Japonica Hybrid Rice in Northern China

Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was studied with 100 crosses derived from 10 sterile lines × 10 restorer lines. There was a complex relationship between parts of the traits of the two aspects. The angle of the 2nd leaf from the top and single panicle weight played important roles in plant type system and amylose content and grain length in grain quality system. The angle of the 2nd leaf from the top, plant height and single panicle weight had a great effect on grain quality traits, and amylose content, brown rice rate and translucency were easily influenced by plant type traits. Selection index model indicated that japonica hybrid rice in Northern China with good quality was characterized by broad flag leaf and 2nd leaf from the top, narrow and short 3rd leaf from the top, low plant height, short culm, long and more panicles and low single panicle weight.     

叶型特性与产量构成因素的相关分析

 于1996和1998年对国内外9份高产水稻品种灌浆结实期的叶型特性与产量构成因素进行了相关分析，结果表明：(1)在叶片角度(叶片与茎秆之间的夹角)较小时（<20°），结实率和理论产量都随着功能叶（剑叶、倒2叶和倒3叶）的叶片角度增加而增加，相关性达到极显著水平；(2)千粒重与剑叶长度呈显著的正相关（r＝0.9119**），而与倒2叶、倒3叶的长度呈负相关（r=-0.7029*、-0.8277*），表明剑叶是决定千粒重大小的因素之一，而其余功能叶的影响较小；(3)在叶片曲率较小(<0.015)时，剑叶的曲率与穗粒数呈显著负相关(r=-0.9057**)，表明叶片曲率越大，其相应的籽粒数越少，即披散型叶片不可能提供充足的灌浆物质。     

Plant Temperature and Its Simulation Model of Thermo-Sensitive Genic Male Sterile Rice

Plant temperature (Tp) and its relations to the microclimate of rice colony and irrigation water were studied using a thermo-sensitive genic male sterile (TGMS) rice line, Pei'ai 64S. Significant differences in the daily change of temperature were detected between Tp and air temperature at the height of 150 cm (TA). From 8:00 to 20:00, Tp was lower than TA, but they were similar during 21:00 to next 7:00. The maximum Tp occurred one hour earlier than the maximum TA, though they both reached the minimum at 6:00. Tp fluctuated less than TA. At the same height, during 6:00-13:00, Tp was higher than air temperature (Ta), and Tp reached the maximum one hour earlier than Ta. During the rest time on sunny day, Tp was close to or even a little lower than Ta. On overcast day, Tp was higher than Ta in the whole day, and both maximized at the same time. In addition, Tp was regulated by solar radiation, cloudage and wind speed in daytime, and by irrigation water at night. The present study indicated that a TA of 29.6℃ was the critical point, at which Tp was increased or decreased by irrigation water.Tp and the difference between water and air temperatures showed a conic relation. Tp fluctuation was also regulated by the absorption or reflection of solar radiation by leaves during daytime and release of heat energy during nighttime. By analysis on correlation and regression simulation, two models of Tp were established.