Abstract
The writers studied the effects of tobacco mosaic virus on the yield and quality of tobacco through the different stages of plant growth during the years of 1949, 1950 and 1952. As observed in the different plot of inoculation effected on the day of transplanting, on the 15-th day after transplanting, on the 30th day after transplanting, and the plot of non-inoculation with the virus, the virus registered a reduction of 42%, 38%, 32%, and 10% on the yield and reduction of 61%, 62%, 37% and 15 % in quality when expressed as damage for unit, this reduction represent 77%, 76%, 57%, and 22%, respectively. The difference in the severity of damage between the plot of inoculation on the day of transplanting and that of 15 days after, the yield and quality of tobacco were found to be very adversely affected by the disease, especially when the infection took place soon after transplanting. The virus affects can, therefore, be roughly measured by the plant growth stage at the time of virus infection.
