Studies on Tobacco Culture in the Subtropical Conditions : IV. Effects of wind on rooting and growth of tobacco in its early stage

[摘要] In order to investigate the effects of wind on rooting and growth of tobacco in its early stage, potted seedlings of flue-cured tobacco (variety; Coker 319) were grown under the condition of the constant wind (3 m/s). The results were obtained as follows; 1. The soil of the wind plot lost moisture from its surface faster than that of control plot under ventilating air current only, especially near the surface of soil. The.soil temperature became lowered by the wind slightly in daytime, while scarcely in nighttime. 2. The rate of leaf emergence of tobacco was apparently depressed by the wind. Its stem length, leaf area and dry leaf weight were distinctly less than those of control tobacco (grown under ventilating air current only), and dry root weight of the wind-treated tobacco was slightly inferior to that of control tobacco. 3. Because of the poor growth of top caused by the wind, the smaller T/R ratio was resulted in the wind-treated tobacco as compared with that in control tobacco. The roots of the former grew longer and reached deepcr in soil than of the latter. 4. When the influence of soil moisture loss on the growth of tobacco in the wind plot was excluded by adjusting the soil moisture tension of the both plots at the same level ( l2 mmHg at 7-9 cm in depth), the growth of top of tobacco in the wind plot was still kept poor as mentioned above, even though it was only slightly improved by the treatment. It was concluded that the windy weather in Okinawa can possibly be the major cause of the poor rooting and growth of tobacco in its early stage in the field there which had been considered to be a typical tendency of tobacco growing in the district of Okinawa.

[学科分类] 农业科学（综合）