:r 9 191996
Uni'ersiti of forida
EVALUATION OF A NEW BIOLOGICALLY-DERIVED NEMATICIDE, ABG 9017,
TO MANAGE NEMATODES IN TOBACCO.
IFAS NFREC Research Report 96: 10
J. R. Rich
University of Florida
Route 3, Box 4370
Quincy, FI 32351
E. B. Whitty
University of Florida
304 Newell Hall
Gainesville, FL 32611
Abbott Tobacco Nematicide Test 1995
The trial reported herein was conducted to evaluate the effectiveness of a new
nematicide, ABG 9017, from Abbott Laboratories to control Meloidogyne javanica on
Materials and Methods
A field trial was conducted on a fine sand soil (93% sand, 4% silt, and 3% clay)
infested with Meloidogyne spp. (primarily M. javanica). In 1994, the site was
previously in tobacco. In early April, the field was moldboard plowed and disced.
Before tobacco transplanting, the plot area was double-disced and herbicide application
was made at that time. On April 11, treatment with Nemacur 3 SC was made and on
April 12, the ABG 9017 was applied. All treatments were applied with a CO2 backpack
sprayer, with Nemacur 3 SC broadcast in 20 gallons of water per acre, and the ABG
9017, 0.10" of overhead irrigation was applied, and the next day, 0.25" was added.
Tobacco cv. Hicks was transplanted 18" apart in-row on April 14. The single
row plots were 48 inches wide and 30 ft. long. The ABG 9017 treatments were
arranged with treated and untreated rows for paired plot comparisons, while the control
and Nemacur treatments were two-row plots. Two additional treatments were made to
one of the 50 lbs. a.i./A ABG 9017 band treatments. A 50 lb. a. i./A, 24" band
treatment was made on May 22, 41 days after the first treatment. Irrigation of 0.25"
followed the treatment after 48 hours. The third and same treatment was made on June
23, 73 days after the first treatment and irrigated immediately with 0.25" of water.
Plants were observed for phytoxotcity and harvested 3 times over the season.
Soil samples were taken on June 26 by removing 6 soil cores per row to a depth of 10".
Samples from individual plots were combined and 100 cm3 extracted by the modified
centrifugation-flotation technique. Root gall ratings (0-4 scale) were taken 2 days after
final harvest from 4 plants in each plot on August 2, 1995. Tobacco was harvested
three times over the season and cured weights recorded.
No phytotoxicity was found in any of the preplant treatments or in the first post-
plant treatment of ABG 9017. However, in the second post-plant treatment, minor leaf
necrosis was evident where the ABG 9017 had been sprayed. Few differences in
nematode numbers were found among treatments and numbers were low at the mid-
season sampling. Paired plot comparisons indicated lowest root galling in the 100 lbs.
a.i./A band treatment with ABG 9017 followed by the Nemacur 3 SC treatment. When
the experiment was treated as a completely randomized block design (east row
comparisons), similar trends of lowest root galling was observed with these two
treatments. Plant growth in plots was good but stands were highly erratic. Yield data
were thus discarded in this test.
Both the ABG 9017 and Nemacur 3 SC reduced root galling compared to the
control treatments. Data were highly variable especially for yield of tobacco due to
"patchiness" of nematode distribution in the test area and greatly differing number of
plants in each plot. A heavy infestation of Ridomil-resistant blue mold reduced number
of plants in random plots. Root galling data, however, indicated consistent activity of
the ABG 9017 in reducing this parameter of nematode infection in tobacco.
Table 1. Paired plot comparionss of ABG 9017 treated and untreated tobacco root gall
Nemacur 3 SC
50 + 50 + 50
Control -- 2.45 (U)
1Predominantly Meloidogyne javanica with some M. incognita.
2All band applications were 24" wide; BCI indicates broadcast and incorporated 4-5"
deep; BC represents broadcast followed by light irrigation.
3Root galling based on a 0-4 scale using 4 plants per plot.
4Treatment applications were made preplant, 41 days and 73 days afterwards.
Table 2. Influence of ABG 9017 on root galling and nematode numbers in a tobacco
Rate in Application Root No. nematodes/
Treatment3 lbs. a.i./A. method3 Galling5 100 cm3 soil
ABG 9017 100 Band 1.25 89
ABG 9017 50 Band 1.55 104
ABG 90174 50+50+50 BC+Band+Band 1.69 72
Nemacur 3 SC 6.0 BCI 1.75 48
ABG 9017 100 BC 2.05 131
ABG 9017 50 BC 2.05 115
Control -- 2.57 87
'Predominantly Meloidogyne javanica with some M. incognita.
2Treated as a randomize complete block design using east row from all treatments.
3Band applications were 24" wide, BCI represents broadcast and incorporated 4-5"
deep, BC is broadcast followed by light irrigation.
4Treatment applications were made preplant, and 41 days and 73 days afterwards.
SRoot galling based on a 0-4 scale using 4 plants per plot.
. I 4