【作者】 殷春渊；

【导师】 赵全志；

【作者基本信息】 河南农业大学 ， 作物栽培学与耕作学， 2007， 硕士

【摘要】 本试验于2004～2006年连续三年在河南农业大学科教园区水稻试验田进行。采用大田和盆栽相结合的试验方法,以黄淮海流域大面积推广的粳稻--豫粳六号和超高产两系杂交籼稻--两优培九为试验材料。在基肥和分蘖肥相同施用量为67.5kg.hm^-2的基础上,设置三种氮素穗肥施用量处理,分别为0 kg.hm^-2（以NO表示）、90kg.hm^-2（以N90表示）、180kg.hm^-2（以N180表示）。针对水稻弱势籽粒充实问题进行研究,分别从物质生产和积累,同化产物运输通道——输导组织,植株体内液流动态,籽粒库容等方面着手,系统地研究了氮素调控下水稻弱势粒充实的作用机理。研究结果如下:1.三个氮素穗肥水平对水稻产量及其构成因素的影响,结果表明,结实率、千粒重、弱势粒充实度处理间差异达显著水平。对于粳稻,后期减少穗肥的施用量可以明显提高强、弱势粒的千粒重,弱势粒充实度增加。穗肥处理对籼稻产量构成因子的影响较小,后期增加穗肥的施用量,强、弱势粒千粒重降低,实际产量增加,这可能是由于穗数、穗粒数的增加弥补了籽粒千粒重、弱势粒充实度的降低。对稻米品质有显著的影响,特别对弱势粒的外观品质影响较大,处理间差异达极显著水平。对于豫粳六号,强势粒的碾磨品质各指标不同氮素穗肥处理间差异均不显著,而外观品质的垩白粒率、垩白度各处理间差异达极显著,垩白面积达显著水平,均以N90处理外观品质较差。弱势粒的稻米碾磨品质各指标不同氮素穗肥处理间的差异较大,NO处理的糙米率分别较N90、N180处理高7.22%和9.36%,差异达极显著水平;精米率分别提高28.05%、31.29%,差异达显著水平;NO处理的不完善粒率较N90、N180处理分别降低72.26%、73.74%,达极显著水平。从外观品质看,垩白粒率,NO处理分别比N90、N180降低了47.96%、34.61%;垩白度分别降低了44.77%、35.68%,差异达极显著水平。对于两优培九,不完善粒率、垩白粒率、垩白面积、垩白度NO明显低于N90、N180处理,其中不完善粒率、垩白粒率、垩白度NO分别比N90、N180处理降低5.6%、37.05%,16.85%、25.2%,18.36%、32.76%。对稻米食味品质的影响与对外观品质的影响基本相同。即随着氮素穗肥用量的增加稻米品质有变劣的趋势。2.籽粒灌浆期,不同氮素穗肥处理对两品种剑叶光合速率及叶绿素影响不同。高穗肥N180处理,叶片叶绿素SPAD值及光合速率明显高于NO和N90处理。粳稻品种处理间的差异高于籼稻。相关分析表明,剑叶光合速率与水稻产量呈正相关关系,但未达显著水平（R=0.399,0.543＜0.666）。3.氮素调控对水稻花后非结构性碳水化合物、氮素的积累与输出的研究,结果表明。籽粒灌浆期,茎鞘中可溶性糖含量的动态变化曲线与淀粉变化趋势大致相同。不同节位茎鞘中可溶性糖含量的变化基本表现为顶二茎鞘〉顶三茎鞘〉顶四茎鞘〉顶一茎鞘。淀粉变化为顶四茎鞘〉顶三茎鞘〉项二茎鞘〉顶一茎鞘,即顶一茎、鞘含量最低。不同处理间,可溶性糖、淀粉含量在灌浆前期变化趋势相同,中后期,N0处理明显高于其他两处理,即N0处理茎鞘物质在后期有回升现象。成熟时茎鞘中糖、淀粉含量均低于开花初期,即茎鞘中的糖、淀粉在籽粒灌浆期内不断向外输出。茎鞘氮素含量的动态变化与之相类似。茎鞘可溶性糖、淀粉输出率随着施氮量的增加而增加,且与产量呈正相关关系。抽穗期的糖花比则正好与之相反,即随着施氮量的增加而降低。从不同处理来看,不论是叶、茎和鞘基本上是N0处理的糖花比较大,N180最小。不同处理间叶、茎、鞘糖花比总和,也表现为相同的规律。相关分析表明,抽穗期的糖花比与弱势粒充实度呈显著或极显著正相关关系,即灌浆初期,茎鞘中贮藏的碳水化合物的量越多,弱势粒充实度越高。茎鞘氮素输出率随着施氮量的增加而降低,且与弱势粒充实度呈极显著正相关关系,与强势粒关系不显著。不同处理间植株叶、茎、鞘的C/N比差异明显,基本表现为N0〉N90〉N180,灌浆各时期植株C/N比与灌浆前期强势粒和灌浆中后期弱势粒的充实度关系达到显著或极显著的正相关水平,这说明,提高植株的C/N比可以提高强、弱势粒的充实度。4.籽粒灌浆期,穗颈节间维管束面积处于动态变化之中,粳稻在花后10天达最大值,籼稻在花后15天达最大值,成熟时面积有所降低,粳稻、籼稻分别比最大值减小4.94%、11.94%。不同氮素处理穗颈节间大维管束面积有差异,基本表现为随着施氮量的增加而增加,N180处理穗大粒多,N0处理穗粒数少。这说明,穗颈节间大维管束面积的大小是形成大穗的基础。强、弱势一次枝梗维管组织面积和维管组织的颖花负荷量结果表明,弱势一次枝梗上下部位维管组织各性状总面积在籽粒灌浆各时期内均大于强势一次枝梗所对应部位的维管组织各性状总面积;二次枝梗上单个籽粒所在小枝梗的维管组织面积,下部弱势籽粒上的小枝梗维管组织面积均大于上部强势籽粒小枝梗维管组织面积。上、下单个一次枝梗维管组织颖花负荷和一次枝梗总颖花负荷,上部大于下部,即单位维管组织面积所负载的籽粒数上部多于下部。整穗同一部位相同维管组织性状的面积基本表现为下部大于上部,同一部位相同维管组织性状的颖花负荷量表现为上部大于下部。对于下部一次枝梗来说,不论是维管组织面积还是颖花负荷量,均优于上部籽粒。即下部一次枝梗不但维管组织发达,而且单个籽粒所分配的维管组织通道也较多。然而,对于上部强势枝梗,尽管维管组织通道不如下部,单位维管束面积颖花负荷量也较大,但充实度却远高于下部籽粒,这表明,对于强、弱势粒灌浆充实差异的研究,维管组织通道可能不是籽粒充实差异的限制因子,单位维管束或单位韧皮部面积上通过的同化产物的量可能是其影响因子。源库调节进一步表明,弱势粒充实度与正常源库结构下的弱势粒充实度差异较大,成熟时剪上三枝处理弱势粒充实度大幅度提高,粳稻、籼稻平均分别比正常穗提高了18.4%、12.86%;剪半叶处理弱势粒充实度有所下降,粳稻、籼稻平均分别比正常穗降低2.06%、12.15%。5.籽粒灌浆期,穗颈节间伤流强度较基部节间波动大,总体上伤流强度呈下降趋势。花后5天,基、穗部伤流强度达最高值,之后基部伤流呈下降趋势,穗颈节间于花后11天下降到最低,之后又上升,达一个高峰后又降低。即,当基部节间伤流下降的同时,穗颈节间的物流运输仍处于旺盛的代谢状态与籽粒灌浆相一致。比较不同氮素处理,基本表现为随着施氮量的增加伤流强度呈下降趋势,穗颈节间表现明显。基、穗部伤流液中可溶性糖的变化规律基本相一致,前期上升后期下降,不同处理差异明显。穗颈节间伤流,无论强度和成分均与弱势粒充实关系密切。相关分析表明,基、穗部伤流强度与籽粒充实度基本上呈正相关关系,其中穗颈节间伤流强度与弱势粒充实度和相对充实度关系最为密切,在籽粒灌浆各时期内基本上达显著或极显著水平,即穗颈节间伤流强度越大,灌浆盛期强、弱势粒灌浆差异较小,弱势粒充实度较高。在籼稻中,伤流强度和充实度关系不如粳稻密切。但两品种穗颈节间伤流液中可溶性糖含量与弱势粒充实度均呈极显著正相关关系。6.籽粒灌浆期,穗、基部液流强度日变化规律基本一致,呈抛物线型变化趋势,但昼夜间存在量上的差异。粳稻基部节间液流强度,白天基本表现为N180〉N90〉N0,夜晚三处理的液流强度几乎均为零。不同处理间穗颈节间的液流强度差异明显,尤其夜间的液流强度处理间差异较大。弱势粒充实较好的NO处理夜晚液流强度远大于N90和N180。相关分析表明,粳稻夜晚穗颈节间液流强度与弱势粒充实度关系达显著正相关水平。但籼稻品种关系不显著。7.籽粒灌浆期,不同粒位籽粒充实度与粒重增长趋于同步。强、弱势粒灌浆速率在初期差异明显,在开始灌浆的5～10d,强势粒的灌浆速率明显高于弱势粒,粳稻平均比弱势粒高137.6%,籼稻强势粒比弱势粒高137.35%。籽粒相对充实度与产量构成因素基本上呈正相关关系,与加工品质呈正相关关系,与外观品质基本呈负相关关系。这说明,通过提高弱势粒的灌浆速率,缩小与强势粒的灌浆差距,提高籽粒相对充实度。有利于改善籽粒（特别是弱势粒）的外观品质和碾磨品质。8.强、弱势粒中可溶性糖和淀粉含量研究结果表明,可溶性糖含量,籽粒灌浆前期呈迅速下降趋势,灌浆后期变化幅度较小,基本趋于稳定状态;淀粉含量的变化趋势与可溶性糖含量基本相反。NO处理强、弱势粒中可溶性糖含量低于N180,而淀粉含量高于N180。说明,随着氮素穗肥的减少,籽粒合成淀粉的能力增强。不同处理间弱势粒的差异表现明显。更多还原

【Abstract】 Widely used as rice cultivar in the Yellow and Huai River and two line hybridize rice,yujing6 and liangyoupei9 had been made experiments.Three treatments of N0,N90 and N180 were designed for studying grain plumpness respectively from dry matter accumulation,the assimilation products transportation channels-transfusion tissue,the dynamic change of sap flow,grain sink and so on at the base of the same quantity of basal fertilizer and tiller fertilizer.By field and pot experiments,the study on mechanism of inferior grain plumpness under panicle nitrogen regulation was carried out on experiments farm of Henan Agricultural university from 2004 to 2006.The results were as follow:1.The effection of nitrogen fertilizer on the yield components was studied.The results showed that seeding setting percentage,1000-grain weight and inferior grain plumpness were rather significantly among treatments.For yujing6,1000-grain weight and inferior grain plumpness were increased by spike nitrogen fertilizer application decreasing in the later grain filling.The number of spike and spike grain of NO were decreased.But the differences of treatments were not significant.For liangyoupei9,the effection of nitrogen fertilizer on the yield components was little. 1000-grain and actual yield increased because of more spikes and spike grain per mu.Three spike nitrogen fertilizer levels had effection on inferior grain rice quality significantly.The differences of treatments were rather significantly.For yujing6, milled quality of superior grain among treatments was not significant.Appearance quality such as chalky percentage,chalkiness and chalky area were significant.Brown rice percentage and milled rice percentage of NO comparing to N90 and N180 respectively increased by 7.22%,9.36%,28.05%,31.29%,and the differences of which were significant or rather significantly.Imperfect rice percentage,chalky percentage and chalkiness of NO comparing to N90 and N180 respectively decreased by 72.26%,73.74%,47.96%,34.61%,44.77%,35.68%,and the differences of which were significant or rather significantly.For liangyoupei9,Imperfect rice percentage, chalky percentage,chalky area and chalkiness of NO were lower than that of N90 and N180,amonge which Imperfect rice percentage,chalky percentage and chalkiness of NO comparing to N90 and N180 respectively decreased by 25.2%,18.36%,32.76%. The effection of nitrogen fertilizer on eating quality was the same as appearance quality.That is to say rice quality will get worse with spike nitrogen fertilizer application rising.2.Photosynthesis of flag leaf and chlorophyll in two varieties were different under nitrogen regulation during grain filling.The chlorophyll SPAD and Photosynthesis of N180 were higher evidently than NO and N90.The difference of yujing6 was greater than liangyouopei9.The yield of N90 and N180 were greater than NO because of higher photosynthesis of flag leaf.The correlation analysis revealed that the relationship between photosynthesis of flag leaf and yield was positive.3.The output and accumulation of stem and sheath after anthesis under nitrogen regulation were studied.The results showed that the change trend of soluble sugar and starch in the stem and sheath was the same.The soluble sugar and starch contents of different nodes displayed basically that contents decreased with the node rising approximately.Among treatments,NO was higher than the others in the middle-later stage.The soluble sugar and starch contents of stem and sheath in the ripe stage all decreased over that of the early anthesis stage.That is to say sugar and starch of plant were output gradually during grain filling stage.The dynamic change of nitrogen content of plant was the same as sugar and starch.Export percentage of soluble sugar and starch of stem and sheath increased with nitrogen fertilizer application rising,which was positive relationship with yield.But the NSC/panicle is opposition with it.From surveying treatments,NSC/panicle or total NSC/panicle of leaf,stem and sheath of NO were higher than the others.The relationship between inferior grain plumpness and NSC/panicle in the heading was positive significantly.That is to say the more accumulation substance in the early grain filling,the higher inferior grain plumpness.The inferior grain plumpness of NO was high probably because NSC/panicle of NO was high and accumulation substance of per panicle was more and the grain filling startup potential was strong.On the contrary,grain plumpness was low.The nitrogen output percentage deceased with spike nitrogen fertilizer application rising,and was positive significantly relationship with inferior grain plumpness.The C/N of leaf,stem and sheath of treatments was different evidently,which decreased with spike nitrogen fertilizer application rising approximately.The relationship between C/N of plant and superior grain plumpness in the prior grain filling stage and inferior grain plumpness in the middle-later grain filling stage was significant or rather significant.So grain plumpness might be proved by raising C/N of plant.4.Vascular bundle area in the neck internode was changed during grain filling and decreased in the ripe stage.Yujing6 and liangyoupei9 decreased respectively by 4.94%,11.94%,comparing to the maximum.Vascular bundle area was increased basically with spike nitrogen fertilizer application rising.Spike grain number of N180 was more,but inferior grain plumpness of it was low.So the big vascular bundle of neck internode was the base of forming big spike probably.The area and load of vascular bundle tissue in the first branch were studied. Vascular bundle tissue characteristics areas of the top and bottom of the inferior first branch and small branch of per grain in the second branch were greater than that of superior first and second branch.However,the load of vascular bundle tissue was on the contrary.The number of grain unit vascular bundle area on the top branch was greater than that of the bottom.So surveying of rice spike vascular bundle tissue structure,vascular bundle tissue characteristics areas of the same position manifested that the bottom was greater than the top.However,the load of vascular bundle tissue of the same position manifested that the top was greater than the bottom.Whether area or load of vascular bundle tissue,the first branch in the bottom was superior to that of the top.Vascular bundle tissue of the bottom was more abundant,and distributing more channels to per grain. Superior grain plumpness was greater than inferior grain although vascular bundle channels of the top was inferior to the bottom and the load of vascular bundle of the top was greater than the bottom.Accordingly,it was indicated that the restrictive factor of the grain filling difference between superior and inferior grain was not the vascular bundle channels,but the assimilation products of flowing through unit vascular bundle tissue.Under source and sink adjustment,inferior grain plumpness varied remarkably compared to inferior grain plumpness under normal source and sink structure condition.Inferior grain plumpness of top three branches removed was improved on the large scale.Japonica rice was improved by 18.4%and indica rice was improved by 12.86%.Inferior grain plumpness of half leaf removed of stem descended on the small scale.Japonica rice was reduced by 2.06%and indica rice was reduced by 12.15%.5.The fluctuating of bleeding intensity of neck internode was greater than that of the basal internode.The change trend of bleeding intensity was descent.The bleeding intensity achieved the maximum 5 days after anthesis.The bleeding intensity of neck internode descended the low level 11 days after anthesis.After it reached the second peak,it decended again.That was to say the bleeding intensity of neck internode was still actively metabolic situation.Comparing to treatments,the bleeding intensity of two positions descended with spike nitrogen fertilizer application rising,of which the neck internode manifested distinctly.The change regularity of soluble sugar was the same as the bleeding.The correlation analysis revealed that the relationship between grain plumpness and the bleeding intensity of two positions was positive.The relationship between the bleeding intensity of the neck intemode during grain filling and inferior grain plumpness and relative plumpness was significant or rather significant level.The greater bleeding intensity of the neck intemode,the smaller difference between superior and inferior grain filling.But for liangyoupei9,the relationship was not distinct with yujingr.The relationship of soluble sugar in bleeding of neck internode and inferior grain plumpness was positive rather significant level.6.The daily change trend of sap flow of neck and basal intemode was parabolic and the intensity between day and night was different during grain filling.The sap flow of basal internode increased with spike nitrogen fertilizer application rising in the day.At night,the sap flow of basal internode of three treatments was almost zero, which was consistent with plant transpiration.The differences of sap flow of neck intemode at night among treatments was great.The sap flow of neck internode at night of NO was greater than N90 and N180,which indicated probably that the sap flow of neck internode at night might be close relationship with grain filling at night. The correlation analysis revealed that the relationship between sap flow of neck internode at night and inferior grain plumpness was positive rather significant level.7.During grain filling stage,grain plumpness of different positions was rising along with weight of grains.The difference between superior and inferior grain filling was evident.The super-grain filling rate were 137.6%and 137.35%more than that Of inferior-grain at early grain-filling stage(5-10 days after heading)respectively in Japonica and indica rice.Grain relative plumpness was being connected to yield components factor and was related to rice quality closely.It was positive relationship with rice milled quality and was being connected reversely to appearance quality.It indicated that improving the grain filling rate of inferior grain,reducing the difference between inferior grain and superior grain,improving grain relative plumpness can improve the appearance quality and milled quality of rice grain,especially inferior grain.8.The research about soluble sugar and amylum content in superior grain and inferior grain indicated that soluble sugar content descended quickly in the early of grain filling and varied slowly in the later of grain filling,which was steadily on the whole;amylum content varied reversely.Soluble sugar content in superior grain and inferior grain of NO was smaller than N180.But amylum content in superior grain and inferior grain of NO was larger than N180.It indicated that the difference of inferior grain in treatments was big along with spike nitrogen fertilization reduced and the faculty of composing amylum improved.更多还原