钾肥用量及基追肥比例对烤烟干物质累积和钾素吸收动态的影响

Effects of potassium application rate and its supplemental proportion on dry matter accumulation and potassium absorption of flue-cured tobacco.

采用田间小区试验研究了钾肥用量及基追肥比例对种植于红壤性水稻土上的烤烟干物质积累和钾素吸收动态的影响．结果表明，烤烟干物质累积高峰出现在烟株移栽后50～60d，栽后30d内以及80d后累积较少．烤烟干物质累积总量随钾肥用量增加和追肥比例提高而增加．烟株含钾量在移栽后30～50d最高，随后迅速降低，至成熟期仅为最高含钾量的一半．315kg·hm^-2施钾处理在各生育期烟株平均含钾量均显著高于225kg·hm^-2施钾处理．烟叶成熟时，225kg·hm^-2施钾处理出现干物质累积负增长和钾素损失现象，而315kg·hm^-2处理干物质累积和吸钾总量均呈持续增加趋势．成熟时基追肥比例为3：7处理的烟株含钾量明显高于基追肥比例为5：5和7：3的处理．

A fidd trial with flue-cured tobacco conducted on a red paddy soil showed that the dry matter accumulation in the tobacco reached a peak in 50- 60 days after transplanting, but was lower within 30 days or over 80 days after transplanting. The dry matter accumulation was increased with increasing K application rate and its supplemental proportion. The K content in the tobacco got its peak in 30- 50 days after transplanting, and then went down, with the K content at maturing stage being as half as that in the peak period. The K content of the tobacco in each growth stage was obviously higher with 315 kg·hm^-2 K application than with 225 kg·hm^-2 K application. At maturing stage, the dry matter and K contents in the tobacco decreased with 225 kg·hm^-2K application, but increased with 315 kg·hm^-2 K application, and the K content was higher with 70 % K supplemental proportion than with 50 % and 30 % K supplemental proportion.