The Effect of Water Supply on the Growth of lzmir, Palotina and Amarelinho Tobaccos

The Oriental tobacco variety Izmir has been grown in sand culture in a greenhouse under various degrees of water stress. Plants given 400 cm³ of water (or nutrient solution) twice a week produced leaves of approximately the same size as field-grown Izmir tobacco, but they were somewhat taller. Plants given 25 cm³ or less of water twice a week died, and those given more than 400 cm³ of water twice a week grew larger than field-grown Izmir tobacco. At 49 days after transplanting, the total leaf area per plant was approximately proportional to the amount of water supplied, at least in the range 100-1600 cm³. In a second water stress experiment, the growth patterns of the varieties Amarelinho and Palotina, which are not normally grown in conditions of water stress, were found to be different from that of Izmir. Izmir was more tolerant of water stress than the other two varieties, in that complete (but small) plants developed in a shorter time.