烟草叶片生长的动态分析

A dynamic analysis of tobacco leaf growth

对烟草品种 K32 6叶片的发生和叶面积扩展规律进行了动态研究。结果表明 ,K32 6烟草叶片的出叶速度前期慢、后期快 ,前期(4～ 8叶 ) 5～ 6 d、中期 (9～ 18叶 ) 2～ 3d、后期 (19～ 34叶 ) 1～ 2 d出一片叶。叶片的长宽比在 1.4 5～ 2 .6 3之间 ,长宽比在低位叶处较小 ,随叶位的上升而增大 ,在高位叶又有所下降 ,打顶后的高位叶长宽比值下降较小。各叶位叶片长、宽和叶面积均有相似的扩展规律 ,用 Richards方程拟合有很高的拟合度。使用该方程 ,可以获得一些与烟叶生长、发育和烟叶生产相关的生长参数。平均而言 ,达到最终叶面积一半的时间约需 16 .4 d,生长速率达最大值约在出叶后 14 .77d。达到最终叶面积 99%的实际生长期约需 36 .8d。打顶后 ,叶片的实际生长期更长。各叶位的长、宽和叶面积随叶位的增加而增加 ,至 2 5叶后 ,增加的幅度变小 ,这种变化趋势也可用Richards方程较好的描述。

Research was made on growth and development of tobacco leaf by intensive observation in leaf growing period with variety K326. Result showed that the growing rate of leaf was slow at early and fast at late stages. 5~6 days were needed to have a new leaf for the early leaves (4~8), only 2~3 days or 1~2 days for middle leaves (5~18) and late leaves (19~34) respectively. The ratio of leaf length to width was between 1.45 to 2 63, lower for earlier and later leaves and higher for middle ones. All leaves follow the similar expansion rule. They were fitted well with Richards equation with high goodness of fit (R +2), so their growth could be described with the equation. On average, 16.4 days was needed to reach the half of the final leaf area. The maximal growth rate of leaf area was about 17.44 days after its appearing. The practical leaf growing period (reaching 99% of the potential leaf area) was about 36.8 days. Tobacco leaf maintained a long period of continuous growth after a fast growing stage, especially for those plants after topping. The leaf increased its area slowly, greatly, and slowly again with the increase of leaf position. This process could be fitted with Richards equation as well.