【作者】 郭江；

【导师】 肖凯； 张凤路； 赵春江；

【作者基本信息】 河北农业大学 ， 作物栽培学与耕作学， 2005， 硕士

【摘要】 采用平展型玉米品种高油115、中间型品种农大108和紧凑型品种郑单958三个不同株型类型的玉米为材料,通过田间试验,研究了灌浆期不同株型玉米品种的群体结构特征、群体光分布特征和不同叶位叶片光合作用及其相互关系,主要研究结果如下: 1 对株型结构特征参数茎叶夹角、叶向值、向茎性和叶面积指数研究表明,不同株型玉米品种相比,郑单958的茎叶夹角均最小,全株叶向值和穗位叶以上叶片的叶向值最大,而叶片的向茎性大于高油115和农大108;高油115的叶面积指数(LAI=6.7)在密度达到7.125万株/hm~2以后增加缓慢,郑单958和农大108达到最大LAI的密度大于高油115。随着种植密度的增加,不同株型玉米的茎叶夹角和叶向值减少、向茎性增强、LAI增大。 2 从玉米群体分组的LAI研究表明,穗叶组的LAI所占总LAI的比例大于粒叶组和茎叶组。其中,不同株型品种穗叶组的LAI大小表现为高油115>农大108>郑单958;粒叶组的LAI大小在不同株型品种间的差异较小;茎叶组的LAI表现为郑单958>农大108>高油115。表明紧凑型玉米可以增加种植密度,提高光合叶面积指数达到增加穗数,最终实现高产的目的。 3 不同株型品种灌浆期间群体上方和群体内部的光通量密度日变化呈早晚低、中午高的单峰曲线。郑单958群体中、下部的透光率和光通量密度高于农大108,后者又高于高油115。随着种植密度的增大,不同株型品种群体的光通量密度降低。但在高密度(7.125万株/hm~2)下,郑单958群体中、下部的光通量密度明显高于农大108和高油115。郑单958株型紧凑,在生育中后期群体中下部具有较高的透光率和光截获量,是其适宜于相对高密度种植的重要生理基础。 4 不同株型玉米的消光系数(K)一日内的变化均呈中午低,早晚高的向下单峰曲线;随着密度的增加K值增加。不同株型品种相比,群体上部上午时的K以高油115较高,农大108和郑单958较低;群体下部的K值则表现为高油115低于农大108和郑单958。群体下部早晚时的K在株型间的差异较小。 5 不同株型品种的光合速率日变化均呈单峰曲线变化,没有出现“午睡”现象。在高密度(7.125万株/hm~2)条件下,不同株型玉米的光合速率在不同群体水平表现为群体上部>群体中部>群体下部。不同株型品种相比,群体上、中、下不同部位的光合速率表现为郑单958>农大108>高油115。随光通量密度的增加,不同株型玉米品种群体各部位的光合速率随之增加。表明郑单958在高密度条件下,仍然能够将光能较为合理地分布在群体内。 6 不同株型玉米品种单叶的最大光合速率表现为农大108最高,郑单958次之,高油115最低。表观量子利用效率在植株下、中、上不同叶位均以郑单958最高,农大108次之,高油115最低。不同株型玉米品种的暗呼吸速率均表现出随叶位的升高而上升趋势。不同株型玉米品种穗位叶的蒸腾速率、叶表蒸汽压亏缺和气孔导更多还原

【Abstract】 Based on the field experiment, the population structure, population light reception and their effects on photosynthesis of different leaf positions during grain filling stage had been studied using maize hybridizations with different plant-types, including Gaoyou 115, Nongda 108 and Zhengdan 958 representing plant-type of flat, semi-flat and erectophile, respectively. The results were as follow:1 The parameters of population structure characteristics including angle between stem and leaf, leaf orientation value, leaf upward stem property and leaf area index (LAI) in the hybridizations with different plant-type were studied. Among different hybridizations, Zhengdan958 had the lowest values of the angle between leaf and stem, the highest leaf orientation values in the leaves above the ear leaf, and the leaf upward stem propertys of Zhengdan 958 was above Gaoyou 115 and Nongda 108;LAI of Gaoyou115 rised slowly when the planting density exceeded 71,250 plant/hm2. The densities of Zhengdan 958 and Nongda108 were above the Gaoyou115 when the LAI of Zhengdan 958 and Nongdal08 were the largest. With the rising of planting densities, leaf orientation values and angles between stem and leaf reduced, while leaf upward stem property and LAI increased in the hybridizations with different plant-type.2 The analysis of LAI in different population showed the proportion of LAI of the ear leaf group was above grain leaf group and stem leaf group. Among different hybridizations, Gaoyou 115 was the largest, Nongda108 was second, Zhengda 958 was the lowest at LAI of the ear leaf group; the difference of LAI at the grain leaf group was less among the hybridizations with different plant-type; LAI at the stem leaf group in Zhengdan958 was above Nongda108 and Gaoyou115 was the last. It indicated erectophile maize could increase the number of spikes by increasing the planting density and improving photosynthetic LAI, and realized high yield at last3 The PAR diurnal change over population and within population was low in the morning and evening, while it was high at noon during grain filling stage in the hybridizations with different plant-type. Comparing the penetration rate and PAR at middle part or underlayer of population among different hybridizations with different plant-type, zhengdan958 was the highest, the next wasNongda108 and Gaoyoul 15 was the last. PAR in the hybridizations with different plant-type reduced with the rising of planting densities. But under the high density (71,250 plant/hm2), PAR at middle part and underlayer of population in Zhengdan958 were higher than Nongda108 and Gaoyoul115 obviously. Because Zhengdan958 was erectophile, which had PAR with high penetration rate 、 light intercept and capture amount at middle part and underlayer of population during the metaphase and anaphase stage.This was a important physiological base to plant under high density.4 The extinction coefficient diurnal change presents single apex curve: high in the morning and evening, low at noon downward; the extinction coefficient increased with the rising of planting density. Different population had different extinction coefficient exhibition among the hybridizations with different plant-type. The extinction coefficient at the upside in Gaoyoul 15 was higher than Nongda108 and Zhengdan958 in the morning; the extinction coefficient at the underlayer in Gaoyoul 15 was lower than Nongdal08 and Zhengdan958 in the morning. The difference of extinction coefficient at the underlayer population was less in the morning and evening among the hybridizations with different plant-type.5 The Pn diurnal change was single apex curve among the hybridizations with different plant-type, it didn’t appear the "siesta" phenomenon. Under the high density (71,250 plant/hm2),Pn in different population increased from the upside part to the underlayer. Comparing Pn of hybridizations with different plant-type, it showed that Zhengdan958 was the highest and Nongda108 was higher than Gaoyoul 15. With the rising of planting density, Pn at the different part increased among the hybridizations with different plant-type. Under the high density, Zhengdan958 could still make the light distribute rationally in the population.6 The most Pn of the single leaf showed Nongda108 was the highest, secondly was Zhengdan958 and the lowest was Gaoyoul 15 among the hybridizations with different plant-type. The order of apparent quantum yield was Zhengdan95、 Nongda108、 Gaoyoul 15 with different leaf position. Following the rising of the leaf position, the dark respiration rate ascended within the hybridizations with different plant-type. The transpiration, vapor pressure deficiency on the leaf surface and gas stoma enhanced with the rising of PAR, while relative humidity had reverse tendency.7 The chlorophyll content in the different leaf position represented middle part>upside>underlayer among the hybridizations with different plant-type. The chlorophyll content fell ceaselessly with the rising of planting density among the hybridizations with different plant-type. The relativity analysis indicated, there was no correlation between Pn and chlorophyll content at the different leaf position under different density among the hybridizations with different plant-type.8 The specific leaf weight at different leaf position represented upside leaf>middle part leaf>underlayer leaf among the hybridizations with different plant-type. Along with the rising of planting density, the specific leaf weight at different leaf position was down. There was remarkable positive correlation between specific leaf weight and Pn among the hybridizations with different plant-type.9 Under the same density, the yield was increased according to Zhengdan958, Nongda108 and更多还原