Dermacor X-100 Seed Treatment for Rice Water Weevil Control

Dermacor X-100 Seed Treatment for Rice Water Weevil Control
Block 8S
Beaumont, TX
2009
PLOT PLAN
⇐ North
I II III IV
1 5 9 3 17 8 25 3
2 4 10 7 18 2 26 7
3 3 11 1 19 7 27 8
4 8 12 5 20 3 28 4
5 2 13 6 21 5 29 6
6 6 14 4 22 1 30 5
7 7 15 8 23 6 31 1
8 1 16 2 24 4 32 2
Plot size: 7 rows, 7 inch row spacing, 18 ft long, with barriers
Variety: Cocodrie @ 80 lb/A (seed provided by LSU Foundation Seed)
Note: smaller numbers in italics are plot numbers
TREATMENT DESCRIPTION, RATE AND TIMING
Rate
Treatment no. Description a (fl oz/cwt) (lb ai/A) b
1 Dermacor X-100 1.25 0.041
2 Dermacor X-100 1.75 0.057
3 Dermacor X-100 2.0 0.065
4 Dermacor X-100 2.5 0.081
5 DPX-HGW86 1.75 0.057
6 DPX-HGW86 2.5 0.081
7 Karate Z --- 0.03
8 Untreated --- ---
a All treatments are seed treatments except Karate Z (applied before flood)
b Based on 18,800 Cocodrie seeds/lb
1
M.O. Way ⋅ moway@aesrg.tamu.edu ⋅ (409)752-2741 ext.2231
Texas AgriLife Research and Extension Center at Beaumont ⋅ 1509 Aggie Dr. ⋅ Beaumont, TX 77713 ⋅ http://beaumont.tamu.edu

Dermacor X-100 Seed Treatments for Rice Water Weevil Control
Agronomic and Cultural Information
Experimental design: Randomized complete block with 8 treatments and 4 replications
Planting: Drill-seeded Cocodrie @ 80 lb/A into League soil (pH 5.5, sand 3.2%, silt 32.4%,
clay 64.4%, and organic matter 3.8 - 4.8%) on May 21
Plot size = 4ft x 18 ft with metal barriers
Emergence on May 30
Irrigation: Flushed (temporary flood for 24 hours, then drain) block on May 21
Permanent flood (PF) on Jun 18
Fertilization: All fertilizer (urea) was distributed by hand.
113.3 lb N/A (2/3 of 170) on May 21 at planting
56/7 lb N/A (1/3 of 170) on Jul 10 at panicle differentiation
40 lb N/A on Aug 8
Total N = 210 lb/A
Herbicide:
Treatments:
Stam 80EDF @ 2.0 lb, Basagran @ 0.75 lb, Facet 75DF @ 0.25 lb and Ordram
@ 2.0 lb (AI)/A and Agri-Dex @ 1.0 pt/A with a 2-person hand-held spray
boom (13- 80015 nozzles, 50 mesh screens, 16 gpa final spray volume) on Jun 8
for early season weed control
All seed treatments applied by DuPont
Treatment 7 (Karate Z @ 0.03 lb ai/A) applied using a hand-held, CO 2
pressurized, 3 nozzle (800067 tips with 50 mesh screens, 29 gpa) spray rig on
Jun 18
Sampling: Recorded bird damage to all plots and estimated % loss on Jun 2
Stand counts (3, 1 ft counts on rows 2, 4 and 6) on Jun 17
Rice water weevil (RWW) cores (5 cores per plot, each core 4 inches diameter, 4
inches deep, containing at least one rice plant) were collected on Jul 10 and Jul
20. Core samples were stored in a cold-room, later washed through 40 mesh
screen buckets and immature RWW counted.
Counted number of whiteheads (WHs – measure of stalk borer damage) in rows
1 – 3 and 5 – 7 of each plot on Sep 1
Harvest: Harvested plots on Sep 3
Size harvested plot = 7 rows, 7 inch row spacing, 18 ft long
Data analysis: RWW and WH counts transformed using x + 0.5 ; yields converted to 12%
moisture; all data analyzed by ANOVA and means separated by LSD
2
M.O. Way ⋅ moway@aesrg.tamu.edu ⋅ (409)752-2741 ext.2231
Texas AgriLife Research and Extension Center at Beaumont ⋅ 1509 Aggie Dr. ⋅ Beaumont, TX 77713 ⋅ http://beaumont.tamu.edu

Dermacor X-100 Seed Treatments for Rice Water Weevil Control
Discussion
None of the seed treatments affected rice stands (Table 1). Populations of RWW were
relatively low but still above treatment thresholds in untreated plots on both sample dates. All
treatments provided excellent RWW control on both sample dates. Dissection of rice plants
revealed the predominant stalk borer species in the experiment was Mexican rice borer. All
Dermacor X-100 seed treatments provided excellent control of stem borers and significantly
reduced WHs compared to DPX-HGW86 and Karate Z plots. However, the high rate of DPX-
HGW86 significantly reduced WH numbers compared to the untreated. The average increase in
yield over the untreated for all Dermacor X-100 treatments was 831 lb/A. The high rate of DPX-
HGW86 outyielded the untreated 932 lb/A.
Table 1. Mean data for Dermacor X-100 seed treatment study. Beaumont, TX. 2009.
Rate b Stand No. RWW c /5 cores WHs c /4 Yield
Treatment a (lb ai/A) (plants/3 ft) Jul 10 Jul 20 rows (lb/A)
Dermacor X-100 0.041 32 1 b 1 bc 2 d 7958 a
Dermacor X-100 0.057 28 0 b 0 c 0 d 7131 bc
Dermacor X-100 0.065 32 0 b 0 c 1 d 7568 ab
Dermacor X-100 0.081 30 0 b 0 c 0 d 7515 ab
DPX-HGW86 0.057 32 0 b 1 b 18 a 7072 bc
DPX-HGW86 0.081 31 0 b 0 c 8 c 7644 ab
Karate Z 0.03 31 0 b 0 c 10 bc 7280 bc
Untreated --- 30 29 a 23 a 15 ab 6712 c
NS
a All treatments are seed treatments except Karate Z (applied before flood)
b Based on 18,800 Cocodrie seeds/lb
c RWW (larvae + pupae); WHs = whiteheads
Means in a column followed by the same or no letter are not significantly different (P = 0.05,
ANOVA and LSD)
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M.O. Way ⋅ moway@aesrg.tamu.edu ⋅ (409)752-2741 ext.2231
Texas AgriLife Research and Extension Center at Beaumont ⋅ 1509 Aggie Dr. ⋅ Beaumont, TX 77713 ⋅ http://beaumont.tamu.edu