Genetic Analysis and QTL Mapping of Large Flag Leaf Angle Trait in Japonica Rice

Genetic segregation analysis for flag leaf angle was conducted using six generations of P1, P2, F1, B1, B2 and F2 derived from a cross of 863B （a maintainer line of japonica rice） and A7444 （a germplasm with large flag leaf angle）. Genotypes and phenotypes of flag leaf angle were investigated in 863B （P1）, A7444 （P2） and 141 plants in BC^F~ （863BIA744411863B） population. An SSR genetic linkage map was constructed and QTLs for flag leaf angle were detected. The genetic map containing 79 information loci was constructed, which covers a total distance of 441.6 cM, averaging 5.6 cM between two neighboring loci. Results showed that the trait was controlled by two major genes plus polygene and the major genes were more important. Fifteen markers showed highly significant correlations with flag leaf angle based on single marker regression analysis. Two QTLs （qFLA2 and qFLA8） for flag leaf angle were detected by both composite interval method in software WinQTLCart 2.5 and composite interval method based on mixed linear model in QTL Network 2.0. The qFLA2 explained 10.50% and 13.28% of phenotypic variation, respectively, and was located at the interval of RM300 and RM145 on the short arm of chromosome 2. The qFLA8 explained 9.59% and 7.64% of phenotypic variation, respectively, and was located at the interval flanking RM6215 and RM8265 on the long arm of chromosome 8. The positive alleles at the two QTLs were both contributed from A7444.

Relationship Between Allelopathic Effects and Functional Traits of Different Allelopathic Potential Rice Accessions at Different Growth Stages

In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperature>leaf stage>light,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.

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.

农药液滴在水稻叶面的动态润湿铺展行为

【目的】探究表面张力、液滴粒径和叶片倾角对农药液滴在水稻叶片近轴面、远轴面动态润湿铺展行为的影响,为通过调控农药液滴在水稻叶面的动态润湿铺展行为实现水稻施药的“减施增效”提供依据。【方法】通过调节Silwet-408的浓度配制出表面张力为21.4、33.2、43.7 mN·m^(-1)的Silwet-408溶液代替农药药液,利用液滴发生器生成532、627、746、830、957μm的单液滴,对其在倾角为40°、65°、85°水稻叶片近轴面、远轴面的动态润湿铺展行为进行全因子试验。【结果】表面张力、液滴粒径、叶片倾角均显著影响(P<0.05)水稻叶面的液滴接触角变化率,且近轴面、远轴面所受影响的整体趋势基本相同,增大叶片倾角或减小液滴粒径或降低表面张力均能增大接触角变化率,促进液滴润湿铺展。其中,以降低表面张力的效果最显著,当表面张力从33.2 mN·m^(-1)降至与水稻叶面临界表面张力接近的21.4 mN·m^(-1)时,叶片近轴面的接触角(前进角和后退角)变化率分别增大7.49、6.22倍,远轴面的分别增大11.13、7.61倍,液滴的润湿性在75 s内从较差或差(80°≤接触角<100°或接触角≥100°)转变成中等或好(60°≤接触角<80°或接触角<60°);当表面张力比水稻叶面临界表面张力大得多时,接触角变化率随叶片倾角的增大而增大,随液滴粒径的减小而增大,但叶片倾角的影响小于液滴粒径的影响,经过75 s后,几乎所有粒径的液滴仍保持较差或差的润湿性(80°≤接触角<100°或接触角≥100°)。液滴润湿滞后现象分析表明,水稻叶面的粗糙度相对较小,液滴润湿滞后现象并不严重。表面张力与水稻叶面临界表面张力接近的液滴在固-液-气三相体系动态表面张力的驱使下在叶面润湿铺展,接触角随时间的动态变化可使用模型θ=θe+Aexp(-Kt)进行拟合;表面张力比水稻叶面临界表面张力大得多的液滴虽能稳定地黏附在叶面上,没有出现滚落现象,但始终未突破叶面的钉扎效应和滞留阻力,无法实现润湿铺展。【结论】表面张力、液滴粒径、叶片倾角3个因素均显著影响农药液滴在水稻叶面的动态润湿铺展行为,在实际施药场景中,由于叶片倾角无法人为调节,因此可根据施药的目的调节药液的表面张力和液滴粒径进而调控液滴的动态润湿铺展行为。研究结果有助于理解农药液滴在水稻叶面动态润湿铺展的机理,并可为水稻施药场景中合理选择药液表面张力、液滴粒径提供理论支持与指导。

基于Android手机的水稻剑叶角测量系统

为了快速、无损地测量水稻剑叶角,设计了基于Android智能手机的便携式水稻剑叶角无损测量系统。采用智能手机后置摄像头获取水稻剑叶基部图像,经过图像预处理、直线检测、K-means聚类和向量方法等处理过程,得到水稻剑叶角。基于Android编程技术对系统软件进行设计,实现了在Android平台下利用JNI和Android NDK调用基于Open CV库的剑叶角提取图像处理算法,实现了新建试验、材料信息输入、摄像头获取剑叶基部图像、计算输出剑叶角及保存数据等界面操作流程。利用该测量系统在田间对4个品种的80株水稻进行剑叶角测量试验,以验证系统性能。试验结果表明,和人工用量角器测量结果相比,该系统测量的平均绝对误差为1.34°,相对误差为2.7%,测量值和真实值相关系数为0.997,能有效测量剑叶角。

遗传、气象和栽培因素对烤烟茎叶夹角的影响

【目的】为明确不同因素对烤烟茎叶夹角的影响。【方法】2019—2021年,在不同烟区设置不同试验,研究不同品种、气象、密度、施氮量等因素变化对烤烟茎叶夹角的影响,并分析不同因素的影响程度。【结果】(1)不同烤烟品种茎叶夹角差异显著,根据聚类分析将其分为茎叶夹角小、中、大三种类型,夹角小代表品种为红花大金元,夹角中代表品种包括中烟100、K326、云烟87等,夹角大代表品种为CB-1;(2)随移栽期推迟,茎叶夹角表现出减小的趋势,气温升高及累积光照辐射减少是影响夹角变化的主要气象因素,降水对夹角的影响不显著;(3)随株距增大、密度减小,茎叶夹角呈现出增大的趋势;部分试验随施氮量增加,茎叶夹角呈现增大趋势;(4)不同因素处理条件下茎叶夹角与农艺性状相关性不一致,品种因素下茎叶夹角与茎围正相关性较高,密度因素下茎叶夹角与叶片干重存在显著正相关性,而移栽期、施氮量条件下茎叶夹角与农艺性状无明显相关性;(5)不同因素对茎叶夹角的影响程度顺序为品种>密度>移栽期>施氮量。【结论】烤烟茎叶夹角受品种自身遗传因素的影响最大,其后依次为种植密度、气象条件,施氮量影响最小。

Biomimetic fabrication and characterization of an artificial rice leaf surface with anisotropic wetting

In nature,rice leaves exhibit special anisotropic sliding capabilities.Although researchers have succeeded in fabricating artificial rice leaf structures and realizing the wettability function of the leaf surface,these methods used to date are complex and do not allow the fabrication of surfaces with large area.Herein,we adopted a simple technology—two steps soft transfer to fabricate biomimetic rice leaf.The fabricated surface well reproduced the structures of the rice leaf surface and exhibited a static superhydrophobic property similar to that of the real rice leaf surface.In terms of its dynamic wettability,it clearly exhibited an anisotropic sliding property.Systematic measurements showed that the sliding angles parallel and perpendicular with the vein direction were 25° and 40°,respectively.The method was simple and reliable,without the need for expensive instruments and complex technologies,which could be used for the rapid fabrication of large-area artificial rice leaf surfaces.We believe that the artificial rice leaf surface fabricated by this method has great potential applications in biomimetic functional surfaces,microfluidics,and so on.

水稻根系分布与叶角关系的研究初报

1983—1984年,通过群体水培、土培试验,在控制水稻根系不同分布空间形状情况下,研究了叶角与根系分布的关系,其结果主要表现如下:1.根系分布较深且多纵向时,叶角较小,叶片趋向于直立;根系分布较浅且少纵向时,叶角较大,叶片趋向于披垂。2.叶角的大小同时受叶片大小的影响,根系分布较浅且少纵向时,较大的叶片更易披垂,叶角更大,根系分布较深且多纵向时较大的叶片仍可保持直立,较小的叶片更易直立,叶角更小。试验指出:叶角的大小在很大程度上受根系分布的调控。在群体叶面积指数较大的情况下,培育分布深而多纵向的根系,有利于改善群体通风透光,增加群体光合作用和提高产量。

Rl_((t))卷叶基因对杂交稻经济性状的影响

以两对卷叶等基因系杂交组合为研究对象 ,设置两种施肥水平 ,研究Rl(t) 卷叶基因对杂交稻产量及产量构成因素的影响。结果表明 ,正常肥力水平下 ,卷叶组合秧苗期的叶龄、茎蘖数、假茎粗、苗高等指标均低于对应组合 ,本田前期茎蘖数上升较缓 ,高峰苗较少 ,而最终有效穗数显著或极显著多于对应组合 ,平均穗粒数和千粒重稍低于对应组合 ,最终结实率和单株产量显著或极显著高于对应组合。增施穗肥处理中 ,各组合倒数 3张叶片均显著或极显著拉长 ,平展叶组合的叶基角和披垂度有较明显的增加 ;各组合穗粒数显著或极显著增加 ,千粒重降低或显著降低 ,平展叶组合结实率显著或极显著降低而卷叶组合结实率变化不明显 ,卷叶组合极显著增产而平展叶组合增产不显著。说明Rl(t) 基因在高肥水平下更有利于其丰产潜力的发挥。

Rl_((t))卷叶基因在杂交水稻中的遗传表达及效应研究

以 Rl(t) 卷叶基因的一对近等基因系卷叶珍汕 97B、珍汕 97B为母本 ,分别与明恢 6 3、盐恢 5 5 9杂交 ,研究 Rl(t)卷叶基因在杂交稻中的遗传表达及效应。结果表明 :(1)开花期 ,相同叶位间 ,Rl(t) 卷叶组合的叶片卷曲度极显著大于其对应组合 ;不同叶位间 ,卷曲度均以倒 1叶最大 ,倒 2叶次之 ,倒 3叶最小。相同叶位的叶基角 ,卷叶组合小于对应组合 ,卷叶汕优 5 5 9与汕优 5 99相对应的倒 1、倒 2叶叶基角差异不显著 ,其余组合对应叶位之间叶基角存在显著或极显著差异。相同叶位的披垂角 ,卷叶组合小于其对应组合 ,卷叶汕优 6 3与汕优 6 3对应叶位之间差异显著 ,卷叶汕优5 5 9与汕优 5 5 9间差异不显著。卷曲度与叶基角及披垂角之间存在极显著的负相关关系 (r=- 0 .35 84* * ,r=-0 .2 996 * * )。 (2 )开花后 2 0天 ,各组合的叶基角均增大 ,卷叶组合增大幅度大于对应组合 ;各组合叶片披垂角均增大 ,卷叶组合增大幅度小于对应组合。 (3)开花后 2 0天 ,各组合的消光系数均大于开花期 ,卷叶组合消光系数在不同时期均显著小于对应组合。 (4 )开花期组合间叶绿素含量差异不明显 ,开花后 2 0天 ,卷叶组合叶绿素含量极显著高于对应组合。就 Rl(t)

栽插密度与施氮量对双季稻上部三叶叶长和叶角的影响

于2007和2008年,采用裂区设计,以双季早稻中早22和双季晚稻天优华占为材料,研究了栽插密度与施氮量对上部三叶的叶长和叶角的影响及其与产量的关系。结果表明,在低氮情况下,增加栽插密度可提高产量,而在中高氮条件下,适当降低栽插密度有利于获得高产。倒一至倒三叶叶长随施氮量增加而增长,随栽插密度下降而增长。中早22的倒一至倒三叶的基角、开张角和叶长与稻谷产量呈抛物线关系;天优华占的倒一至倒三叶的基角和开张角与稻谷产量呈抛物线关系,而倒一至倒三叶叶长与稻谷产量呈直线关系。产量最高时中早22倒一叶基角、开张角和叶长的适宜值分别为11.37°、7.81°、29.74cm;倒二叶基角、开张角和叶长的适宜值分别为17.27°、16.06°、36.08cm;倒三叶基角、开张角和叶长的适宜值分别为21.76°、24.70°、39.02cm;天优华占倒一叶基角和开张角的适宜值分别为11.62°、12.30°;倒二叶基角和开张角的适宜值分别为32.61°、30.08°;倒三叶基角和开张角的适宜值分别为23.55°、31.21°。

水稻剑叶角度的QTL分析

以剑叶角度差异显著的籼稻窄叶青 8号和粳稻京系 17以及由它们构建的加倍单倍体群体为材料 ,在抽穗期测量其剑叶角度 ,并利用该群体构建的分子图谱进行数量性状座位分析。分别在第 1、2、3和 12染色体上检测到 4个QTL(qFLA 1、qFLA 2、qFLA 3和qFLA 12 ) ,贡献率分别为 10 .6 %、11.8%、9.8%和 8.1%,其中qFLA 1、qFLA 2的加性效应来自京系 17,qFLA 3和qFLA 12的加性效应来自窄叶青 8号。多个增效等位基因的聚合明显提高剑叶角度。讨论了这些控制剑叶张开性状的QTL在常规稻和杂交稻育种上的应用前景。

糖蜜和米糠对香蕉茎叶青贮饲料品质的影响

【目的】考察单独或联合添加糖蜜和米糠对香蕉茎叶青贮饲料品质的影响,为寻找出便于推广应用的青贮发酵方法提供参考依据。【方法】在对香蕉茎叶进行青贮发酵时,分别设添加4%乳酸菌(LAB组)、4%乳酸菌+4%糖蜜(糖蜜组)、4%乳酸菌+4%米糠(米糠组)、4%乳酸菌+4%糖蜜+4%米糠(混合组)4个处理组及不添加任何辅料的对照组,青贮30 d后对各青贮饲料品质指标进行测定分析。【结果】与对照组相比,4个处理组青贮饲料的发酵品质明显提高,其感官评分均高于51分,达到良好或优等青贮饲料的标准。其中,添加米糠(米糠组、混合组)可降低青贮饲料的水分含量,提高粗蛋白含量;添加糖蜜(糖蜜组、混合组)可明显改善青贮饲料的感官品质,提高蛋白质含量,降低pH、氨态氮和单宁含量;联合添加糖蜜与米糠(混合组)不仅显著提高了青贮饲料的干物质和粗蛋白含量,还有效降低了氨态氮、粗纤维和单宁含量,呈协同作用。【结论】复合添加乳酸菌、糖蜜和米糠能改善香蕉茎叶青贮饲料品质,显著提高青贮饲料的消化利用率和营养价值。

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。

不同叶片卷曲度杂交水稻的光合特性比较

在田间条件下研究了叶片卷曲度不同的 6个代表性杂交水稻组合在开花期和花后 2 0天上部 3张叶片的卷曲度和剑叶叶片近轴面 (上表面 )、远轴面 (下表面 )光合强度、叶片角度、挺直度、群体消光系数的关系。结果表明 ,剑叶卷曲度高的组合叶片卷曲度达 4 4 %～ 4 7% ,中等的组合为 15%～ 16% ,低的组合为 10 %～ 11%。高叶片卷曲度组合的剑叶上表面 ,由于受自身叶片遮光的影响而使光合强度低于下表面 ,下表面与上表面光合强度比为 1.19～ 1.32 ,中等叶片卷曲度组合为 0 .90～ 1.0 2 ,低叶片卷曲度组合为 0 .82～ 0 .85。与叶片卷曲度低的组合相比 ,叶片卷曲度高和中等的组合具有较小的叶片角度、较高的叶片挺直度和较低的消光系数。

不同成熟度烤烟叶片主脉叶绿体的差异

以烤烟品种K326和G80中部叶为材料,分别在打顶前、欠熟、适熟、过熟阶段取样,用丙酮浸提法测定叶片主脉叶绿素含量;用石蜡切片法制片观察和测定叶片主脉基本组织细胞中的叶绿体数量,并动态记录茎叶夹角的变化.结果表明,叶片主脉叶绿素含量和叶绿体数量随着成熟度的提高而降低,叶绿体解体加快.K326和G80在茎叶夹角为50°左右时,处于适熟阶段.

水稻茎、叶的营养含量及留茬高度对稻草营养品质的影响

随着我国畜牧业的快速发展,稻草的利用也大幅度增加。稻草通常被列为低质粗饲料,品种不同,其营养价值变化较大。本研究对泰优99、渝香203、丰优22、Ⅱ优368和培杂泰丰5个水稻品种的农艺性状、茎叶营养含量和消化率进行了测定,并探讨了留茬高度对5个品种稻草营养含量的影响。结果表明,丰优22在农艺性状、粗蛋白含量、茎叶消化率等方面表现较好,相对于其他4个品种具有更高的饲用价值;水稻叶的粗蛋白质和粗灰分含量比茎高,无氮浸出物含量和干物质消化率比茎低;留茬高度对稻草营养含量影响不大,水稻收割应留茬3～5cm,以便增加稻草产量。

两系杂交稻结实期茎鞘物质转运特性及其对籽粒灌浆影响的初步研究

选用３个不同类型两系杂交稻组合，结实期研究茎鞘物质转运特性及其与籽粒灌浆的关系，结果表明：各组合以下部茎鞘物质积累多、转运率高；两优培特和汕优１０号茎鞘物质转运启动时间早、转运强度大，其转运率高，结实率较高，表明早期转运对籽粒灌浆充实的重要性；茎鞘物质转运高峰较籽粒灌浆高峰滞后１～２ｄ，表明茎鞘物质转运与籽粒灌浆活力有关。

向日葵叶片在空间分布特性的初步研究

对向日葵叶片叶茎夹角、叶面积、株高、茎粗等形态指标的研究表明 :在生育期中叶茎夹角在孕蕾期达到最大 ,不同品种之间差异较大 :“白 971”最大为 5 7 9° ,“参ck”最小为 49 2° ,品种间的变异系数为 5 8%～10 4% ;叶面积呈单峰曲线 ,最高峰在末花期 ,品种之间差异较大 ,ck最大为 5 75 0 7cm2 ,“白 95 2”最小为44 4 79cm2 ,品种间的变异系数为 5 5 %～ 6 5 % ;株高呈单峰曲线 ,最高峰位于乳熟期 ,品种之间有差异 ,“白 971”最高为 2 6 3 9cm ,“白 95 1”最低为 2 34 6cm ,品种间的变异系数为 4 5 %～ 5 3 % ;茎粗也呈单峰曲线变化 ,最高峰位于末花期 ,品种之间有差异 ,ck最粗为 3 14cm ,“参ck”最细为 2 88cm ,变异系数在 2 3 %～3

施液量、雾滴大小、叶片倾角及助剂对农药在稻叶上沉积的影响

固定农药剂量条件下,综合分析施液量、雾滴大小、叶片倾角及助剂对农药在水稻片上沉积的影响,为稻田的农药高效施用提供科学依据。以生物染料丽春红-G为示踪剂,采用自动行走式喷雾塔,配置3种TEEJET喷嘴TP80050、TP8002、TP8005进行细雾滴、中等雾滴及粗雾滴喷雾,分析农药在倾角为0°、15°、30°、45°、60°、75°、90°水稻叶片上的沉积量随施液量变化的规律。研究结果表明：施液量、雾滴大小、叶片倾角和助剂四个因素对农药的沉积都有显著影响,且影响效应叶片倾角〉施液量〉雾滴大小〉助剂。丽春红-G在稻叶上的最大沉积量随叶片倾角值θ的增大,呈减少趋势。对于细雾滴喷嘴TP80050,丽春红-G的沉积量先随施液量的增加而增加,达到最大值后继续增加施液量,沉积量减少。对中等雾滴喷嘴TP8002和粗雾滴喷嘴TP8005,施液量20~40 L时,丽春红-G沉积量即达到最大值,加大施液量则减少沉积量。不添加助剂,低施液量时丽春红-G沉积量TP8002〉TP8005〉TP80050;高施液量且叶片倾角θ〈45°时,TP80050沉积量最高;θ≥45°时,雾滴大小间无显著差异。添加助剂,低施液量时TP8002沉积量高,高施液量时TP80050沉积量高。施液量、雾滴大小、叶片倾角及助剂4个因素均能影响水稻叶片上的丽春红-G沉积,且存在互作效应。建议田间喷雾时,根据叶片形态、药液表面性质及喷嘴特性科学确定施液量及是否添加助剂。