【作者】 吴正锋；

【导师】 王空军； 董树亭； 胡昌浩；

【作者基本信息】 山东农业大学 ， 作物栽培学与耕作学， 2004， 硕士

【摘要】 高油玉米是一种籽粒含油量高、品质优的高附加值玉米新型品种,由于其产量偏低,难以在生产中大面积推广应用,影响到其优质特性的发挥。本研究为探明高油玉米籽粒产量的限制因素,以大田放任生长的种植密度在开花期减源和半量不饱和授粉(疏库)处理,比较研究了高油玉米的源、库生理特性。在此基础上研究了氮肥、密度对高油玉米产量、品质和源-库生理特性的影响,探讨了高油玉米高产优质的可行性途径。试验主要结果如下。1 高油玉米产量表现 放任生长条件下,高油玉米的单株籽粒产量显著低于普通玉米,只有普通玉米的 90.6%。产量构成中,高油玉米的穗粒数和普通玉米相当,千粒重显著低于普通玉米,只有普通玉米的 85.5%,较高密度下(45000～62500 株/hm2),高油玉米的产量是普通玉米的 92.54%,产量构成中,千粒重比普通玉米低 5.08%,说明千粒重低是高油玉米产量低的主要因素。2 高油玉米的产量受叶源相对不足的限制 疏库时,高油玉米单粒重显著增加,平均增重 9.69%;普通玉米平均增重 1.65%,但未达显著水平。减源 1/2,高油玉米单粒重显著减少,平均减重 7.74%;普通玉米平均减重 5.73%,未达显著水平。两类型玉米相比,高油玉米单粒重对叶源相对减少(减源)或相对增多(疏库)的反应更为敏感。证实了高油玉米的产量(单粒重)受叶源相对不足的限制。3 高油玉米的叶源特性 从授粉至成熟期高油玉米的叶面积、叶面积持续期及果穗叶光合速 1<WP=9>吴正锋:高油玉米源-库生理特性及产量潜力研究率、光合色素含量、叶片含氮量均低于普通玉米,尽管授粉后其叶面积、叶片含氮量和光合速率下降慢,但难以弥补因叶面积和光合速率小而对产量的影响,表明了高油玉米的产量受源数量少和活力偏低的双重限制。 高油玉米果穗叶的 SOD、POD、PEP 羧化酶等酶活性及可溶性蛋白质含量,随源/库比的减小而降低,叶片的光合速率、光合色素含量等随源/库比的减小而显著增加,且增幅大于普通玉米。 高油玉米的叶面积系数、光合势随施氮量和密度的增加而增加,增幅小于普通玉米。而叶片的光合速率、净同化率、光合色素含量、含氮量、PEP 羧化酶活性等均随施氮量的增加呈上升趋势,随密度的升高而下降,降幅小于普通玉米。说明高油玉米源活性随施氮量的增加而升高,而对密度调控的反应不敏感。4 高油玉米的籽粒库特性 高油玉米和普通玉米的单株库容量相当,但高油玉米的最大籽粒灌浆速率小,籽粒充实度低。 玉米籽粒灌浆速率随生育进程的推进而降低,随源/库比的增加而增加,高油玉米的增幅较大。高油玉米的单籽粒干重随施氮量增加而增加,随密度的上升而降低,两类型玉米相比,氮肥处理对高油玉米籽粒干重的影响较大,密度处理影响较小。高油玉米籽粒的氮、磷、钾含量随施氮量的增加而升高,与普通玉米相比,高油玉米籽粒氮增幅较小,磷、钾含量增幅较大。5 源-库改变及氮肥与密度对高油玉米籽粒品质的影响 高油玉米籽粒粗蛋白质、粗脂肪含量均显著高于普通玉米,淀粉含量和普通玉米相当。 高油玉米的粗脂肪含量随叶源的增大而降低,高油玉米的降幅较大;高油玉米粗蛋白含量随源/库比的增加而显著增加,与普通玉米相比,高油玉米的增幅较大;源-库改变对淀粉含量的影响较小。 高油玉米粗蛋白质、粗脂肪及淀粉含量随施氮量的增加而升高,随密度上升降低。与普通玉米相比,氮肥和密度对高油玉米籽粒粗蛋白、淀粉含量的影响较小,而对粗脂肪含量的影响较大。 2<WP=10>山东农业大学硕士研究生毕业论文更多还原

【Abstract】 High oil corn(HOC) is a value-added corn cultivar’s type,which containsmore oil and higher quality protein than that of normal corn (NC). HOC hasnot been widely planted by growers because its grain yield is lower than NC.The experiment was conducted to document the limited factor of High OilCorn (HOC) grain yield which is the assimilate supply (source strength) or theinherent potential of the kernel (sink capacity). The physiologicalcharacteristics of source and sink were studied on HOC by defoliation and halfpollination of the topmost ear at flowering in field under freely growingconditions. Then the effects of different nitrogen and density treatments on thephysiological characteristics of source and sink, the grain yield and grainquality of HOC was studied compared with NC. The feasible methods forhigher grain yield and better grain quality were put up. The major results asfollowing:1 The components of grain yield of HOC Compared with NC, the grain yield of HOC was 90.6 percentage of thatof NC. As to the components of yield, the different of 1000-kernel weightdistinct between both HOC and NC under freely growing conditions,1000-kernel weight of HOC was 5.08 percent lower than that of NC underother density. But no significant difference was found between kernel numberper ear.2 The limited factor of HOC grain yield 4<WP=12>山东农业大学硕士研究生毕业论文 The effect of altered source-sink ratio on dry weight per kernel wassignificant. Half pollination of topmost ear, the dry weight per kernel of HOCincreased distinctly, about 9.69 percent higher than that of control plant. Thatof NC increased 1.65 percent. When half leaves were clipped, the dry weightper kernel of HOC decreased 7.74%, which of NC only decreased 5.73 percent.Compared with NC, the effects of altered source-sink ratio on dry weight perkernel of HOC is more sensitive, which indicated that a predominant sourcelimitation for grain yield in HOC.3 The Physiological characteristics of leaf source During the period from pollination to physiological maturity, a decreasein leaf area, net photosynthesis rate, photosynthesis pigment, content andnitrogen concentration in ear leaf of HOC was found with development ofstage in maize. The grain yield of HOC is lower than that of NC for its smallerleaf, lower nitrogen concentration in leaf and net photosynthesis rate , thoughthose of HOC decreased slowly after pollination .In conclusion,the grain yieldof HOC was limited by both of the quantity and activity in leaf source. A decrease of source-sink ratio prompted a decrease in SOD activity,POD activity and soluble protein content in ear leaf, the reason of which maybe defoliation caused leaf hurt. Whereas there was a significant increase in netphotosynthesis rate, photosynthetic pigment content, PEP case activity in earleaf and soluble sugar concentration in leaf as the source-sink ratio decreased.In addition, the amplitude of HOC was bigger than that of NC. Both the leaf area index and duration on leaf area of HOC increased witha increase of nitrogen and density treatments. But the amplitude of HOC issmaller than that of NC. An increase was found in net photosynthesis rate,photosynthetic pigment content, Nitrogen concentration in leaf and PEP caseactivity all increased with increase of nitrogen level and decrease of densitybut the degradation lower than NC. That’s to say the source activity of HOCwas better when the nitrogen fertilizer level was high,but the effect ofdifferent density level on it was more sensitive for NC than HOC. 5<WP=13>吴正锋:高油玉米源-库生理特性及产量潜力研究4 The Physiological characteristics of sink HOC has similar potential of sink capacity per ear with NC, but lowergrain filling rate and grain filling index. The grain filling rate of HOCdecreased with development of stage in maize,but increased with a increase ofthe ratio of sourc更多还原