19
Potato Scab and Rhizoctonia Control
The 1937 scab control trials were not continued during the 1938 season
for the reason that no scab infested land was available for such trials.
However, some seed treatment trials for the control of both potato scab and
rhizoctonia were set out on the experimental tract obtained from the Bureau of
Reclamation.
A supply of scabby and rhizoc infested Netted Gem potatoes were obtained and subjected to the following treatments:
°
A. Dry heat for two hours at 55° C. (131 F.)
1. Heat only
2. Hot formaldehyde
3. Corrosive Sublimate
4. Semesan Bel
B. Dry heat for one and one half hours at 60
°
C. (140
°
F.)
1. Heat only
2. Hot formaldehyde
3. Corrosive Sublimate
4. Semesan Bel
C. Check (no heat)
1. No treatment
2. Hot formaldehyde
3. Corrosive Sublimate
4. Semesan Bel
No damage to germination was observed from any of these treatments.
Heat treatments were made in the Horticultural Products experimental drier.
Inside tuber temperature after 2 hours at 131 F. was 118° F. and after 1-0
hours at 140 F. was 120° F.
0
°
This experiment yielded no results so far as scab and rhizoc control
were concerned. It is thought probably that the ground used for the experiment
was too saline for the particular strains of fungi.