XL A g  
i * g 8 Thirty-winth Aamtal Report
I
c   I infection. The records were obtained late in the season. Two
l Q distinct types of mottled mosaic are common in the tobacco
    , fields of Kentucky. These remained very distinct thru fifteen
` °   generations of plants in the greenhouse and when inoculated into
‘ T   plants being set in the field, resulted in marked diEerences in
i ; . rates of growth and type of injury. A third type much like
i .~ Q   one of the former, but differing in that necrotic spots are com-
_ i 3 monly developed in inoculated plants in the greenhouse, was also `
    studied. A virus disease of tobacco characterized by chlorotic
V t   i*   spots in the growing point, rather than by mottling, and by ex-
I ·     tensive necrotic patterns on the older leaves has been studied in
· I     the greenhouse and field and appears distinct from tobacco
_ .   l mosaic as it is ordinarily recognized. The sa.1ne groups of virus
i · ‘ .   diseases found in tobacco have been obtained from tomatoes.
i 2     Ring-spot of tobacco in which no symptoms of mosaic are seen, r
;.i H A     has been found to be nearly as readily transmitted as tobacco
V . i     mosaic, altho infected plants may grow for long periods show-
» _ tl.   ing no symptoms of the disease. A row of burley tobacco
·»   plants in a field inoculated with a mosaic tomato plant de-
g g I .     V veloped a disease which caused the death of all the leaves
l ~ »_  ·—     . present on the plant at the time of inoculation. The midveins
_ “ `   { first became necrotic and long necrotic streaks developed on the
,   l A stalk. The subsequent growth showed mosaic and was very
i °   i_ , much stuntcil. One case of what appeared to be this disease
I       _ was observed in a field of tobacco, completely destroying a
, Y  g   gi g large portion of it.
L A   _   ’ Method of Application of Fertilizers for Tobacco. For the
,__       {ji _ past four years, at the Greenville, Mayfield and Campbellsville
      ’ ‘ soil experiment fields, certain plots ha.ve been divided and the
j       feiftilizers applied broadcast to one-half, and a part of the appli-
  in v_ Y.?  cation put in the hill on the other half. The total application
  _`f`f;   per acre, which was the same in both methods, ranged from 600
  g   ii   to 850 pounds. Nitrate of soda was used at the rate of 200
      pounds per acre in both methods on all the fields. In the hill
    fertilizations, 100 pounds of nitrate of soda was mixed with
igigg  100 pounds of acid phosphate and 50 pounds of potash salts,
  and used in the hill, the remainder of the fertilizers being used
  isn ii .