朱展望　佟汉文　刘易科　陈泠　邹娟　张宇庆　高春保　焦春海

摘要：通过播期和密度两因素试验，对小麦主栽品种郑麦9023不同播期和密度条件下的叶片发育进程进行了比较，对小麦主茎叶龄指数与有效积温的关系进行了研究，并对影响叶热间距的因素进行了分析。结果表明，播期对郑麦9023叶片发育进程影响极显著，密度对郑麦9023前期叶龄指数无显著影响，但在中后期对叶龄指数有显著的影响，播期和密度之间无显著互作。不同播期前期主茎叶龄指数与有效积温呈明显的线性关系，R2为0.991 9～0.996 3，均高于0.990 0，直线斜率为0.009 3～0.010 9。在2月23日后，不同播期的郑麦9023叶龄指数增速明显放缓，显著偏离原来的直线。所有处理郑麦9023叶热间距的平均值为99.5 ℃/叶，叶热间距随播期推迟而降低，随密度增加而增加，但相对于播期而言，密度对叶热间距的影响相对较小。播种后的平均气温、冬季田间总分蘖数AUNTC与叶热间距均呈显著正相关。早播小麦经历的前期高温可能是造成其叶热间距较大的原因；茎蘖数过多引起的光合效率下降，分蘖与主茎的养分竞争可能是引起主茎叶热间距增加的因素。基因型对秋播春性小麦叶热间距的影响有待下一步研究。

关键词：秋播春性小麦；叶片发育；叶龄指数；积温；叶热间距

中图分类号：S512.1 文献标识码：A 文章编号：0439-8114（2015）24-6181-07

DOI：10.14088/j.cnki.issn0439-8114.2015.24.020

Abstract：An experiment with 4 different sowing dates and 3 plant densities for a dominant wheat variety Zhengmai 9023 was conducted. The development process of the main stem leaves of Zhengmai 9023 in different treatments were compared and the relationships between the main stem leaf age indexes of Zhengmai 9023 and the effective accumulated temperature was analyzed. The phyllochron intervals were obtained and their influencing factors were also discussed. The results showed that， the development process of the main stem leaves of Zhengmai 9023 was highly significantly influenced by the sowing date. By contrast， the plant density had no significant effect on that before January 22nd. The interaction between sowing date and plant density either had no significant effect on the development process of the main stem leaves of Zhengmai 9023. Linear regressions were always observed between the main stem leaf age indexes and the effective accumulated temperature under different sowing dates during earlier and middle period of plant growth. The scope ranged from 0.009 3 to 0.010 9 and R2 ranged from 0.991 9 to 0.996 3， with no less than 0.990 0. The increase rate of the main stem leaf indexes of Zhengmai 9023 significantly decreased after February 23rd， with a significant deviation from original straight line. The average phyllochron interval across different treatments was calculated as 99.5℃ per leaf. Phyllochron interval decreased as sowing time of Zhengmai 9023 delayed， while it became higher as plant density increased. The effect of plant density on phyllochron interval was relatively smaller than sowing date. The average air temperature after sowing and the number of tillers during leaves growth were significantly positively correlated with the phyllochron interval. The higher air temperature in the following day after sowing for the earlier sown Zhengmai 9023 could be increased the phyllochron interval of main stem leaves. The decrease of the photosynthetic efficiency caused by redundant tillers and the competition between the tillers and the main stem for the nutrients might increase the phyllochron interval of main stem leaves. The effect of genotypes on the phyllochron interval of autumn-sown spring wheat should be focused on the future study.

Key words：autumn-sown spring wheat； leaf growth； leaf age index； accumulated temperature； phyllochron

叶片是小麦进行光合、呼吸和蒸腾作用的主要器官，其数量和面积决定了干物质的积累和经济产量的形成。小麦叶片的生长速度、大小及颜色的变化等是衡量小麦生长发育状况和长势的主要标志[1，2]。……