Group Title: NFREC Research Report - University of Florida North Florida Research and Education Center ; 97-4
Title: Rates of Chlor-O-Pic to manage the Javanese root-knot nematode in Florida flue-cured tobacco, 1996
Full Citation
Permanent Link:
 Material Information
Title: Rates of Chlor-O-Pic to manage the Javanese root-knot nematode in Florida flue-cured tobacco, 1996
Series Title: NFREC research report
Physical Description: 3 leaves : ; 28 cm.
Language: English
Creator: Rich, J. R ( Jimmy Ray ), 1950-
Whitty, E. B
North Florida Research and Education Center (Quincy, Fla.)
Publisher: North Florida Research and Education Center
Place of Publication: Quincy Fla
Publication Date: 1997
Subject: Tobacco -- Diseases and pests -- Control -- Florida   ( lcsh )
Nematode diseases of plants -- Control -- Florida   ( lcsh )
Pesticides -- Application -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
non-fiction   ( marcgt )
Statement of Responsibility: Jimmy R. Rich and Elmo B. Whitty.
General Note: Cover title.
Funding: Research report (North Florida Research and Education Center (Quincy, Fla.)) ;
 Record Information
Bibliographic ID: UF00074384
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 85762787

Full Text
f 6 0#k-,




NFREC Research Report 97: 4

Jimmy R. Rich
University of Florida
Rt. 3, Box 4370
Quincy, FL 32351

Elmo B. Whitty
University of Florida
304 Newell Hall
Gainesville, FL 32611

Marston Scienco
JUL 21 1997

University of Florida

Chlor-O-Pic Tobacco Nematicide Test 1996

The trial reported herein was conducted to determine the efficacy of three rates of

Chlor-O-Pic to manage the Javanese root-knot nematode in flue-cured tobacco.

Materials and Methods

A field trial was conducted on a fine sand soil (93% sand, 4%clay, 3% silt) infested with

the Javanese root-knot nematode (Meloidogyne javanica). The test site was at the University

of Florida Green Acres farm in Alachua County, and it was previously in bahiagrass in 1994

and 1995. Soil was prepared by moldboard plowing and double-discing. Fumigant treatments

of Telone C-35 and Chlor-O-Pic were applied on March 26, 1996, by single chisel injection to

10" deep in the row. All plots, including controls, were bedded immediately after treatment.

Tobacco cv. NK 371 was transplanted on April 13 and placed 18" apart in the 48" wide rows.

Plots were two rows wide x 30' long, and treatments were placed in a randomized complete

block design with five replications. Tobacco was grown according to standard cultural

practices and irrigated as required. Early season observations were made to detect any

phytotoxicity, and tobacco was harvested four times, cured and weighed. At final harvest on

August 20, five soil cores (1" diam.) were taken to 12" deep in each plot and composite. A

100 cm3 soil subsample from individual plots was processed by a centrifugation-flotation

technique and second-stage juveniles counted. Root-galling was rated from four plants in

each plot on a 0-10 scale where 0 = 0 root galling and 10 = 100% of the root system galled.

Results and Discussion

Early season phytotoxicity was observed in the Telone C-35 and Chlor-O-Pic

treatments. Plants in 1-2 plots of each treatment were stunted and showed slight chlorosis.

Plant symptoms were related to areas where soil contained highest clay content. Tobacco was

transplanted 18 days after treatment but apparently a longer time interval for fumigant

dissipation was needed in these areas. Plants, however, recovered in two three weeks, and

no effects on yield were apparent.

Tobacco yield differences were not found among chemical treatments or treatments and

the control. All treatments significantly reduced root gall ratings compared to the control.

Low root gall ratings and lack of yield differences reflect low nematode population

development and little damage to the tobacco crop. This was probably due to low initial

nematode populations (4 juveniles/100 cm3 soil) resulting from the use of bahiagrass rotation.

To differentiate treatment efficacy, the test will need to be conducted under conditions of

higher initial nematode populations.

Table 1. Effect of Chlor-O-Pic rates on yield and root galling in a Florida tobacco test, 1996.

Treatment Rate in Yield Galling2
gals./A' Ibs./A Index

Telone C-35 9.0 3064 0.27 a3
Chlor-O-Pic 9.0 3019 0.77 a

Chlor-O-Pic 3.0 2949 0.76 a

Chlor-O-Pic 6.0 2916 0.80 a

Control -- 2903 2.00 b

'Fumigants were injected in the row with a single chisel to 10" deep.

2Root galling was rated on a 0-10 scale with 0 = 0 galling and 10 = 100% of the root system galled.

'Column means followed by the same letter are not significantly different (P < 0.05) according to Duncan's multiple range test.

University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs