Title:

 

The Effect of Temik 15G on Cotton Yields in a Minimum Tillage System Infested with Root-knot Nematode at AG-CARES, Lamesa, TX 2001.

 

AUTHORS:

 

Terry Wheeler (TAES) and Aventis Crop Science Inc., Assistant Professor

 

MATERIALS AND METHODS:

 

             Plot Size:                                                4-rows wide with 40" centers, minimum area = 0.28 acres, maximum area=0.52 acres

             Planting Date:                                       May 10, 2001

             Variety:                                                   Paymaster 2326RR

             Design:                                                   Randomized complete block design with 4 replications

             Application Date:                                 June 22, 2001

                                                                              Sidedress Temik and Vydate

             Midseason nematode sampling:       July 15, 2001

             Plant Mapping:                                                  August 16, 2001

             Final nematode sampling:                  September 23, 2001

             Harvest Date:                                        October 3, 2001

 

RESULTS AND DISCUSSION:

 

The midseason root-knot nematode density was lower in 2001 than it has been in the last several years, indicating less nematode pressure at planting for 2001 than most years at AG-CARES. The nematode density at harvest, however, was once again quite high. Temik 15G at or greater than 3.5 lbs/a gave significantly higher yields than not using any Temik (Table 1). Thrips pressure was light at this site, and Orthene 90 was used where no Temik 15G was applied, so the yield response was not due to insect damage.

 

 

 

Table 1. Results from the AG-CARES site.

Temik

Vydatec

Temikd

Height

Nodes

Squares

Missing

1º

2º

Missing

Lbs of lint

 

 

at plant

 

sidedress

 

 

 

Squares

Bolls

Bolls

Bolls

per acre

Pma

Pfb

lbs/a

 

lbs/a

 

 

 

 

 

 

 

 

 

 

0

 0

0

15.5

14.0

3.3

1.1 a

7.3

2.4

5.2

607 b

495

 4,260

3.5

 0

0

15.2

14.1

3.4

0.6 bc

7.9

1.5

5.6

751 a

360

11,280

5

 0

0

14.6

13.7

2.6

0.3 c

7.1

1.5

5.2

737 ab

630

 7,890

5

 0

7.5

15.9

14.1

2.8

1.2 a

8.1

2.0

6.1

759 a

420

 6,285

5

 +

0

15.7

14.1

3.1

0.9 ab

7.5

1.7

5.9

760 a

195

10,770

aPm is the midseason density of root-knot nematode/500 cm3 soil.

bPf is the fall density of root-knot nematode/500 cm3 soil.

cVydate was applied over the top of the cotton at pinhead size square at 8 oz/a and again one week later with the same rate.

dTemik 15G was applied at pinhead size square with a sidedress rig, which lightly incorporated the Temik into the soil.