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。     

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）。     

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。     

新疆多秆、多穗、多叶型玉米产量生理研究

多秆多穗多叶型玉米是近年来在新疆开始推广的一种青贮玉米,由于该杂交种带有多秆多穗多叶基因,比普通的生育期相同的玉米杂交种每株要多出2～3个有效茎、3～5个果穗、30～50片的叶片,而显得尤为特别。目前,多秆多穗多叶型玉米在新疆推广面积约2万hm2。近年来,我们对这种特殊基因型玉米的植物学性状、产量特征、光合产物生产等方面进行了一定的研究和探索。1　多秆多穗多叶型玉米植物学性状及产量特征研究表明,多秆多穗多叶型玉米品种,与普通品种相比,每株要多出2～3个有效茎、植株茎秆较高;每株多出3～5个果穗,果穗略小且在植株茎的中…     

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。     

不同生物有机肥对水稻产量及其构成因子的影响

在折合每667 m2一次性基施纯氮4 kg条件下,尿素处理产量为436.41 kg/667 m2,几种生物有机肥处理的产量在457.10～495.87 kg/667 m2之间,均高于尿素处理,其中以双友生物有机肥处理的产量最高。与尿素处理相比,施用有机肥能够促进水稻分蘖的发生,增加有效分蘖数,提高成穗率、结实率、千粒重,增加水稻产量。     

水稻苗情动态计算机模拟：Ⅰ.水稻发育速度统计模式的比较及应用

本文应用5种水稻发育速度模式估算了8个不同熟期类型品种的发育速度,并应用其模式中的参数,对不同地点和不同年分的生育期进行了逐日模拟,模拟结果与实际观察值相吻合。     

小麦叶面积指数变化的模拟

分段模拟了潜在生产条件下小麦叶面积指数变化,并建立了模拟模型,模型可作为进一步模拟小麦群体生长的基础。     

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.     

小麦叶面积指数的模拟模型研究

小麦叶面积指数计算为群体绿叶与比叶面积的乘积，而绿叶重为其分配指数的地上部干重的乘积。建立了绿叶分配指数与生理发育时间之间的曲线关系。结果表明，模型能较好地模拟叶面积指数的变化动态，其平均相对误差小于10％。     

Spatial Distribution of Leaf Area Index and Leaf N Content In Relation To Grain Yield and Nitrogen Uptake in Rice

Abstract

Exploring Approaches To Optimizing Spatial Distributions of Leaf Area index (Lai) and Leaf Nitrogen Content (Lnc) Should Be Useful For increasing Grain Yield in Rice (Oryza Sativa). THe Primary Objective of This Study Was ToCharacterize The Variation of Lai and Lnc Distributions Within The Canopy in Relation To Grain Yield and N Uptake in Rice.Two Experiments With Different N Fertilization Rates Under Conventional and intermittent Irrigation (Ci and Ii, Respectively) Were Conducted in 2002 and 2003, Using Japonica Rice Cultivar Wuyujing9. The Results Showed That Grain Yield and N Uptake Were Significantly Different Among Application Rates of N (N Rates), But Did Not Differ Between Ci and Ii. Lai Distribution At Full Heading Was Affected Significantly By N Rate But Hardly By The Irrigation Method. individual Lai increased With The N Rate. To Achieve A High Yield, The Proper Distribution of Lai in The Canopy Can Be Designed As The Largest in The 2^Nd Leaf From The Top, Followed By The 3^Rd and 4^Th Leaves, and The Smallest in The Top Leaf. Lnc On The Base of Both Area and Dry Matter At 15 Days After Full Heading Decreased From The Top To Lower Leaves in The Canopy, and Significantly increased With The N Rate. Grain Yield Was Enhanced Linearly With The increasing N Content of The Upper Two Leaves, But Hindered By The High N Content of Lower Leaves. These Results indicate That The Spatial Distributions of Both Lnc and Lai Could Be Optimized To Achieve Maximum Canopy Photosynthesis and Grain Yield in Rice.     

肥料与密度对寒地水稻源库关系的影响

以龙粳14为试验材料,研究了氮磷钾肥用量与密度对源库关系及产量的影响。结果表明:蘖肥氮用量、密度因素与叶面积指数间存在着显著的正相关关系;基肥氮用量、蘖肥氮用量显著影响颖花量,所以适当增加基肥氮用量、蘖肥氮用量、密度都会提高源库质量;源库质量对产量影响显著,叶面积指数、颖花数增大会有效的提高产量。     

穗部和叶部性状对水稻产量的影响

以34个水稻品种或品系为试材,对产量、产量构成因素、穗部性状、叶部性状等进行了研究。结果表明:品种间产量差异极显著,辽盐188、龙盘5号、沈稻9号、辽盐158、沈稻9810等产量较高。产量与成粒率呈显著的正相关,与每穗秕粒数呈显著的负相关,与倒2叶长、倒3叶长也呈显著的负相关。     

Regression-Based Models to Predict Rice Leaf Area Index Using Biennial Fixed Point Continuous Observations of Near Infrared Digital Images

Abstract

A weatherproof digital imaging system for the near infrared band (NIR, 820–900 nm) was positioned 12 m above a 600-m² rice field. During the 2008 and 2009 paddy rice seasons, the system automatically logged images at 10-min intervals throughout the day. Radiometric corrections for the NIR images utilized a solar irradiance sensor and prior calibrations to calculate 0900–1500 JST daily-averaged reflectance factors (DARF). Prior to heading, empirically derived equations for predicting leaf area index (LAI) using the 2008 DARF values in NIR, the cosines of angles between the view and the planting row directions, and between the view and the meridian directions were verified with the 2009 data set. Transformation of a model variable by arcsine square root function improved the performance of the LAI prediction by reducing the errors and bias at low LAI values. Adding variables to incorporate lateral angular components to the horizontal viewing angular parameters hardly affected the overall performance of the models and did not reduce variation. This was probably because the height and position of the camera system were the same in successive years. In-plot means of two or four predicted values in each plot reduced the root-mean square error 30%. These results indicate that radiometric NIR images derived using a fixed-point observation system can accurately predict LAI and the simple multiple linear regression equations developed for a given year can be used the following year without in-situ recalibration.     

抗水稻细条病和水稻白叶枯病转基因水稻植株的获得

抗水稻细条病和水稻白叶枯病转基因水稻植株的获得ＲｅｇｅｎｅｒａｔｉｏｎｏｆＴｒａｎｓｇｅｎｉｃＲｉｃｅＰｌａｎｔｓＲｅｓｉｓｔａｎｔｔｏＢａｃｔｅｒｉａｌＬｅａｆＳｔｒｅａｋａｎｄＢａｃｔｅｒｌａｌＢｌｉｇｈｔｏｆＲｉｃｅ￥中国水稻研究所生物工程系和...     

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).