Mississippi

Summary of nematode survey activity in Mississippi.

Dr. Don J. Blasingame, 508 Colonial Circle, Starkville, MS 39759, phone (622) 323-5646, FAX (same as phone ... call first),
email: Db508pb@aol.com

Major Nematode Species: Root-knot and reniform nematodes economically impact cotton in Mississippi. The Mississippi Delta suffers from medium to high populations of these species, with yield losses proving to be substantial. Research also shows a definite interaction between reniform nematodes and cotton seedling disease.

Other Nematode Species: In 2001, lance nematodes were reported at low densities in 29 counties, with the major concentrations along the north and central portions of the Mississippi Delta. The species found in Mississippi are not as damaging as those found in the Southeast. This parasitic pest will be closely observed, because it could become an economic factor in the near future.

2000 Yield Loss Estimate Valued at $390/Bale: 10% of the cotton crop was lost to nematode damage ... 203,488 bales ... valued at $79,400,000.

2001 Nematode Surveys: 708 fields were sampled in three counties with a total of 375,000 acres planted. These fields represented 5% of the planted acres.

Sharkey County: 160 samples
89% of the samples had reniform nematodes
64.5% were above the threshold level of 5,000 per pint of soil. Less than 2% of the samples contained rootknot nematodes.
64.5% of the acres planted were above threshold levels.
Leflore County: 225 samples
37.3% of the samples had reniform nematodes.
21.3% were above the threshold level of 5,000 per pint of soil.
21% of the samples had rootknot nematodes.
13% were above the threshold level of 350 per pint of soil.
A total of 34.3% of the acres planted were above the threshold levels.
Coahoma County: 323 samples
34% of the samples ha reniform nematodes.
20% were above the threshold level of 5,000 per pint of soil.
23% of the samples had rootknot nematodes.
18% were above the threshold level of 350 per pint of soil.
A total of 38% of the acres planted were above threshold levels.

2002 Activities to Consider in Latter Part of Growing Season: The best time to take nematode soil samples is in the latter part of the growing season. Technology is readily available to effectively reduce nematode populations below damaging levels.

1998 Research Activity: Dr. G. W. Lawrence, Department of Entomology and Plant Pathology, Mississippi State University, P.O. Box 4775, Mississippi State, MS 39726, Phone (601) 325-2988, FAX (601) 325-8837,
email: glawrence@entomology.msstate.edu

Five research tests were conducted in Mississippi in 1998, in which Temik 15G was included. Three tests were done in a reniform nematode infested field, and two tests were conducted in locations infested with root-knot nematodes.

Experimental Design: All tests were done in fields which were naturally infested with either reniform or root-knot nematodes. The experimental design was a randomized complete block with five replications. Rows were 40 feet long; and 38 and 40 inches apart in the fields infested with root-knot and reniform nematodes respectively. Temik 15G was applied at 3.5, 5.0, or 7.0 lbs formulated product per acre. All Temik 15G treatments were applied in the seed furrow at planting. Di-Syston 8EC, or Gaucho seed treatment was included in each test. An untreated control, which did not receive any in-furrow treatment, was also included in specific tests.

For details of test results, contact Jennifer Gimpert.