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 ANF NORTH FLORIDA EXPERIMENT STATION
 Ouincy, Florida
 November 15, 1967

 NFES Miideo Report 68' r I

 CHEMICAL CONTROL OF NEMATODE ROT ROT COMPLEX OF SHADE-GROWN TOBACCO
 NOV 30 1967 ppa


 'OBJECTIVE

 To evaluate the effectiveness of chemical soil treatments in the control of nematode
 root rot complex of shade-groin tobacco.

 MATERIALS AND EQUIPMENT

 Test Materials.--Materials, chemical composition, formulations, and sources are
 presented in Table 1.

 Equipment.--A gravity-flow single-shank injector devised by the North Florida Experiment
 Station was used in all injections. Ground seals after treatment were made with a crosstie
 drag. A rotary tiller was used to mix some of the treatments into the soil after application.

 METHODS AND PROCEDURE

 Experimental Design.--Eleven treatments and an untreated check were replicated four
 times in randomized complete blocks. Plots were approximately 0.0118 acre in size, and
 were located in the west half of the "bug shade". Each plot had four rows, 32 feet long and
 4 feet apart The two inside rows constituted the experimental plot from which data were
 taken. The two outside rows, one on each side of the experimental plot, acted as buffers
 between plots. Alleys between blocks of plots and buffer zones within blocks were 8 feet
 wide.

 Tfeatments.--All plots were fertilized with 20 t6tib of stable manure on December 211
 1964, and 500 pounds pet acte of high calcie lime on january 7, 1965. The plots were
 subsoiled to a depth of approximately 11 inches on January 12, and rotary tilled to a depth
 of approximately 6 to 8 inches on February 3. Most treatments were applied on February 4
 and 5, except the second application of Bayer 25141 which was applied on April 19. Soil
 temperatures at the 6-inch level on February 4 ranged from 480F. at 03:15 P. M. to 510F. at
 04:25 P. M., and on February 5 ranged from 440F. at 08:45 A. M. to 500F. at 03:16 P. M.
 Rain in the amount of 2.11 inches was recorded on February 6. Methods of application were
 as follows: Bayer 25141 broadcast on the soil surface and rotary tilled to a depth of
 6 to 8 inches. A second broadcast application of Bayer 25141 was made at the time of the
 second sidedressing of fertilizer and worked into the soil with the fertilizer covering
 process; Diazinon A-1619 and GA-301-diluted 1:4 in water and injected on 6-inch centers;
 M-2633-injected on 12-inch centers; M-2811-diluted 1:3 in petroleum solvent and injected on
 12-inch centers; and Niagara 10242, Niagara 9227, Penphene, SKF-21701, and UC-21149-broad-
 cast on the soil surface and rotary tilled to a depth of 6 to 8 inches. All treatments
 except the second application of Bayer 25141 were sealed with a drag. Injected treatments
 were applied to depths of 6 to 8 inches. Rows were prepared for fertilizer application on
 March 8, and a 7-5-7 fertilizer was applied at 2,000 pounds per acre in the row on March 9.



- Associate Entomologist, North Florida Experiment Station, Quincy.