Study on canopy structure and physiological characteristics of shenbao No.3 in different densities | 沈爆3号在不同密度下的冠层结构和生理特征研究

Китайский. 摘　　要：在6个密度下研究沈爆3号的冠层结构、生理特征、产量和产量构成因素。结果表明，沈爆3号适合高密度种植且适应密度范围较大，密度在8．25万株／hm. 时产量最高，分别比5．25万、6．00万、6．75万、7．50万、9．00万株／hm. 增产21．96％、22．75％、11．50％、10．64％、7．92％，达到显著或极显著水平。在高密度下穗长、穗粗、行粒数、穗粒数、粒重、秃尖变化较小，单株产量维持较高水平。在9．00万株／hm. 时达到最大叶面积指数（6．55），保持较大的叶面积指数和较长的持续时间。生育后期叶面积指数随密度增加而下降的速度较快，但密度在6．75万～9．00万株／hm. 差异不大，高密度下仍可维持较高水平。不同密度之间穗位叶叶绿素含量存在微小差异，较低密度下最高叶绿素含量的出现时间较迟，而高密度下较早。增加密度使净光合速率下降，但较低密度下增密时下降幅度较大，3个高密度问下降幅度较小。

Английский. Canopy structure, physiological characteristics, yield and yield construction factors were studied under six planting densities. The result showed that Shenhao No.3 was a variety that was suitably planted in high density, and adapted to larger density limits, the highest yield was earned in 82 500 plants/ha, increased by 21.96% and 22.75% respectively than 52 500 plants/ha and 60 000 plants/ha, it was ultra-significant, and increased by 11.50%, 10.64% and 7.92% respectively than 67 500 plants/ha, 75 000 plants/ha and 90 000 plants/ha, it was significant. Second, under the high planting density pressure, there was a little change in ear length, ear diameter, kernel number per row, grain number per spike, grain weight and rare top, the yield of one plant remained high level. Third, the max LAI（leaf area index） reached 6.55 in 90 000 plants/ha, and LAI lasted long time under high density. In the post-growth stage, LAI decreased sharply with the increasing of density, but there was little difference from 67 500 plants/ha to 90 000 plants/ha, namely it still remained high level under high density. Forth, the content of the chlorophyll in ear leaves has a little differences among the different planting densities, unlike lower density in which the time of the highest content of the chlorophyll appeared latter, the higher density was earlier. Last, increasing planting density made photosynthesis rate（Pn） decline, but the rate of decreasing was big when increased density within low density,in contrast, within the three high densities it was small, remaining stronger photosynthetic capacity was the one of the important reasons that Shenbao No.3 was a close-enduring planting variety.