THE EFFECT OF SOIL MOISTURE ON NICOTINE ACCUMULATION DYNAMICS IN DIFFERENT PARTS OF A TOBACCO PLANT (NICOTIANA TABACUM L.)
This paper outlines the ways to increase the yield of nicotine from a tobacco plant and its waste to produce non-smoking products and products. The changes in the nicotine content in the roots and the aerial part with the stem depending on the soil moisture were studied during the cultivation of a tobacco plant in old-irrigated typical sierozems of Kyrgyzstan. It was found that as the soil moisture increases (from 25 to 80 percent of the least moisture holding capacity) the growth of tobacco plants continuously increases. Throughout the experiment, this increase is most clearly expressed by the growth of the aerial part which determines the course of change in the weight of the whole plant. By the end of the first period (on the 50th day after planting), the total content of nicotine (in mg) in plants with lower soil moisture is higher. There is a tendency for a slightly higher content of nicotine in the aerial part of the plants cultivated in the variants with 25 and 40% soil moisture. Most of nicotine is found in the aerial part. In subsequent periods (50 days after planting), the accumulation of nicotine in the plants of the “dry” variant begins to overtake strongly both in the whole plant and in 100 g of fresh herbage in comparison with the “wetter” variant. In the roots, this trend is not detected; the nicotine content in the roots by the end of the first 50 days is almost the same in all variants. Also, regardless of the soil moisture, the constancy of the ratio between the value of root mass increase and the amount of newly formed nicotine remains constant. A completely different ratio occurs during the second period. The increase of the raw mass of the roots at 25 and 40% soil moisture is 1.6-3.4 times greater than that with increased soil moisture (60 and 80%).