氮肥基追比例对烤烟钾积累和分配的影响

Effects of top-dressing to basal nitrogen ratio on potassium accumulation and distribution in tobacco

研究了氮肥不同基追比例对烤烟钾积累和分配的影响。结果表明,烤烟钾主要积累在叶片中,氮肥基追比例对烟叶钾含量的影响大于对烟根、茎钾含量的影响,不同基追比例烤烟钾素积累的差异主要是氮肥基追比对烤烟各器官干物质的差异所致。应避免在烟株移栽时施用较多的氮肥,影响根系生长发育和钾的吸收,降低钾的积累,同时也要注意烟株碳氮代谢的适时转换,增加光合产物和钾的积累。烤烟每茬带出的钾为98.09-104.57 kg·hm^-2,其中烟叶带出的钾为56.51-65.48 kg·hm^-2,茎带出的钾为19.30-22.22 kg·hm^-2,根带出的钾为14.31-22.28 kg·hm^-2。烤烟施入234.00 kg·hm^-2化学钾,仅有41.92%-44.68%由根、茎、叶带出（其中由烟叶带出24.15%-27.98%）,55.31%-58.08%流失或固定在土壤中。

The effects of different ratios of topdressing to basal nitrogen fertilizer on potassium accumulation and distribution in tobacco plant were investigated. The results showed that potassium mainly accumulated in leaves of flue-cured tobacco, in which the potassium contents were higher than those in the root and stem. Potassium accumulation was affected by the ratios of basal to topdressing nitrogen fertilizer due to the accumulation of dry matter in different tobacco organsunder difference nitrogen treatments. Reduction of nitrogen fertilizer at transplanting was beneficial to the growth of root, absorption and accumulation of potassium. In each crop, a total of 98.09-104.57kg·hm^-2 potassium accumulated in whole plants, and 56.51-65.48, 19.30-22.22 and 14.31-22.28 kg·hm^-2 accumulated in leaves, stems and roots, respectively. Thus, only 41.92%-44.68% of 234.00 kg·hm^-2 potassium fertilizer accumulated in tobacco plants（24.15%-27.98% in leaves）, and the rest was run way or fixed in the soil.