TOMATO LEAF-MOLD 



11 



Table 5. Comparative Merits of Fungicides in Preventing Infection of 

 Potted Tomato Plants. Both Leaf Surfaces Treated. 



Fungicide 



Check 



Grape Dust 



Schloesing's Sulfur 



Vaporized Sulfur 



Solbar 1% 



Copper-Lime Dust 20-80 

 Uspulun .5% 



Spores Applied in Water 



Leaflets 

 Counted 



9S 

 117 

 123 

 105 



76 

 82 



Leaflets 

 Diseased 



per cent 



25 .5 

 5.1 



26 S 

 1-9 



S2.S 

 8.5 



Spores Applied Drt 



Leaflets 

 Counted 



117 

 90 

 82 

 60 



110 

 123 



Leaflets 

 Diseased 



per cent 

 67.6 

 23. S 

 17.0 

 1.6 



42.7 

 5S.6 



In another test Bordeaux 4-4-50, Solbar 1 per cent and Uspulun .5 per 

 cent offered a high degree of control when the treated plants were inocu- 

 lated with spores in water (Table 6). When spores were applied dry, only 

 Solbar offered effective control. 



Table 6. Comparative Merits of Fungicides in Preventing Infection of 

 Potted Tomato Plants. 



Fungicide 



Check 



Potassium Sulfide .4^ 



Solbar 1% .' 



Copper Sulfate .05% 



Bordeaux 4-4-50 



Uspulun .5% 



Spores Applied in Water 



Leaflets 

 Counted 



122 

 123 

 126 



129 

 151 



Leaflets 

 Diseased 



per cent 



55.7 



21 .1 



6.6 



0.7 

 7.7 



Spores Applied Dry 



Leaflets 

 Counted 



211 

 108 

 129 

 188 

 146 

 197 



Leaflets 

 Diseased 



per cent 



9.3 

 78.1 

 19.8 

 17.7 



The materials which controlled infection on as much as 85 per cent of the 

 foliage in these experiments are listed in Table 7. When water was used as 

 a carrier for the inoculum, consistent favorable controls were obtained with 

 Bordeaux, copper-lime dust, vaporized sulfur, and Uspulun; while copper 

 sulfate. Slug Shot and lime-sulfur gave favorable control in the single test 

 made. Solbar and Grape Dust were effective in one test and not in another, 

 while Semesan permitted 16.8 per cent of the foliage to become infected 

 against 4.7 per cent with Uspulun. All other fungicides tested were not 

 effective. When spores were applied dry, only vaporized sulfur gave con- 

 sistent control. Solbar gave favorable control in the single test in which it 

 was tried, and Grape Dust was effective in one test and not in another. All 

 other materials failed to offer satisfactory control. The poor control indi- 

 cated by Semesan as compared with Uspulun and by Grape Dust (spores 

 applied dry) were in reality significant controls although less than 85 per 

 cent, the percentage on which Table 7 is based. 



It is significant that when both leaf surfaces were covered with vaporized 



