Dry matter accumulation and nutrient uptake in flue-cured tobacco (Nicotiana tabacum L.)

In a two-year field experiment using flue-cured tobacco, carried out in Agrinio (western Greece), dry matter accumulation (DMA) was studied in addition to the uptake of the nutrients nitrogen (N), potassium (K), phosphorous (P), calcium (Ca), and magnesium (Mg) on a weekly basis during the period from transplant to harvest over two cultivation seasons. Whole plants were sampled and divided into leaves, stalks and roots. These were dried, weighed and DMA and the nutrient uptake determined. Both DMA and nutrient uptake in plant parts as well as in whole plants follows a sigmoidal curve, accurately described by a logistic equation. During growth there is a period when DMA and nutrient uptake in plant parts occurs at an intense rate. The time of onset of this period and its duration varies with different plant parts. Maximum daily DMA occurs when 50% of the maximum plant DMA has been achieved. Maximum daily nutrient uptake in aerial parts of the plant occurs approximately 1 week prior to the maximum daily DMA. The period of rapid DMA and nutrient uptake in flue-cured tobacco coincides with the knee-high and budding (rapid qrowth and elongation) stage (41-75 DAT). Consequently during this period, the soil must have sufficient nutrients available to supply the needs of the plant.