From
these calculations it is clear that in the case
of the pepper test, vaccination does reduce
the yield by approximately 15% when
compared with healthy plants. However,
when one compares the yield from unprotected challenged plants (D) with the protected and challenged plants (S/D), the
yield of the protected plants is 23 to 58%
higher, depending on the virus strain used
for the challenge infection. The yield from
preinoculated melon, on the other hand,
was exactly the same as that of the healthy
plants, while the unprotected infected
plants yielded only 47% that of the protected plants. This comparison is also visually evident when the fruit from each
treatment is piled at the end of the row
from which it was picked (Fig. 2E and F).