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Cotton Grower Meetings, 2010 Insect Management . Jack Bacheler Dominic Reisig NCSU. Cotton insect control cost estimates North Carolina, 2009. Foliar treatments for thrips 2003-09 Consultants Survey. % treated. At-planting options: Consultants’ clients, 2009. % selected. 47.3. 39.1.
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Cotton Grower Meetings, 2010 Insect Management Jack Bacheler Dominic Reisig NCSU
Cotton insect control cost estimates North Carolina, 2009
Foliar treatments for thrips 2003-09Consultants Survey % treated
At-planting options: Consultants’ clients, 2009 % selected 47.3 39.1 13.6 Seed Temik Seed + Temik
Foliar treatments for thrips planting option Consultants’ clients, 2009 86.7 68.7 % treated 29.3 Seed Temik Seed + Temik
Bottom line: value of thrips control options, 2005-2009 (12 tests) * Temik = 3.25/ lb.; Orthene = $10.00/ lb.; Seed trt. = $15.90/acre ** @ 800 lb./ acre and $0.65/ lb.; 3.5 seed/ft. & 38” rows
Flaring* of selected products on cotton aphids * Flaring : = none; 3.0 = severe Aeris Temik Avicta Bidrin Acephate Pyrethroid
Spider mite and aphid treatments averaged 2 to 10-fold less with Temik vs. seed trt. + foliar (2004-2009). Ave. = 5.1% 1.4%
Thrips control options based on planting date (Conceptual schematic)
Thrips control options based on planting date (Conceptual schematic)
Thrips control options based on planting date (Conceptual schematic)
High & low temperature April 15 - June 15; Edgecombe Co. 2009 Temperature (*F) May 11 May 20 June 15
Yield difference: Temik or seed trt. + Orthene vs. UT check; Rocky Mount, 2009 (3 tests planted on May 11 & 1 on May 20) +235 +199 +193 +192 +147 Yield gain (lb. lint/acre) +7 - 18 May 11 May 11 May 11 May 20 Temik (5 lb.) Seed trt. + Orthene
Yield difference: Temik or seed trt. + Orthene vs. UT check; Rocky Mount, 2009 (n = 4 tests) +235 This test yielded approx. 100 lb. more lint/acre than ave. of the 1st 3 tests. +199 +193 +192 +147 Yield gain (lb. lint/acre) +7 - 18 May 11 May 11 May 11 May 20 Temik (5 lb.) Seed trt. + Orthene
What have we learned about managing stink bugs?
Declining insecticide use for late season pests in North Carolina apps./ acre Years Era
North Carolina’s major boll damaging stink bug species nymph nymph adult adult nymph Green stink bug Brown stink bug
Proportion of green, brown and southern green stink bugs at SE test locations, 2004-2008 =Green = Brown = Southern green = Other N 04 N 05 N 05 N 05 N 05 N 05 N 06 N 06 N 08 N 08 S 06 S 06 S 07 G 05 G 06 G 06 G 08 G 08 G 08
Average number of stink bugs per 6 row feet (n = 8 tests, 2005-2008) Adults Nymphs Number of stink bugs 1 2 3 4 5 6 7 Week of bloom
Bolls become safe from stink bug damage later in the bloom period
Boll age and size vs. yield loss > 1.25” diam.)
Stink bugs damage cotton less: 1) when there are fewer susceptible bolls early in the bloom period 2) when bolls are no longer susceptible to damage late in the bloom period
Stink bugs damage cotton less: 1) when there are fewer susceptible bolls early in the bloom period 2) when bolls are no longer susceptible to damage late in the bloom period Dynamic threshold (% by week of bloom): 50, 30, 10, 10, 10, 20, 30, 50
Thresholds evaluated: • UTC: untreated control • Wkly bloom: sprayed weekly from 1st wk of bloom • 10% sprayed at 10% with 1 internal symptom • 20% sprayed at 20% with 1 internal symptom • 30% sprayed at 30% with 1 internal symptom • Dynamic 50, 30, 10, 10, 10, 20, 30, 50% by wk If threshold has been met: treatments were with pyrethroid + dicrotophos(e.g., Baythroid @ 0.03 + Bidrin @ 0.25 lb ai/acre)
Stink bug threshold tests (n = 47 total tests; NC, SC, & GA; 2005-2008)
Stink bug levels defined • High/Moderate: 2+ sprays at 20% threshold • Low/Moderate: 1 spray at 20% threshold • Low: 0 spray at 20% threshold
Profit difference between use of 20% vs. Dynamic threshold (n = 47 tests; NC, SC & GA)
Field device for stink bug Scouting in the Southeast
Conventional, BG, WideStrike and BGII against bollworms and stinkbugs, 2005-2009 (n=717 cotton fields) Total damage Stink bug damage Bollworm damage % Boll damage 3.3 0.23 0.12 0.84 BG BG BG WS WS WS BG II BG II BG II Conv. Conv. Conv.
Conventional, BG, WideStrike and BGII against bollworms and stinkbugs, 2005-2009 (n=717 cotton fields) Total damage Stink bug damage Bollworm damage 5.6 5.5 % Boll damage 4.5 3.6 3.3 0.23 0.12 0.84 BG BG BG WS WS WS BG II BG II BG II Conv. Conv. Conv.
Conventional, BG, WideStrike and BGII against bollworms and stinkbugs, 2005-2009 (n=717 cotton fields) Total damage Stink bug damage Bollworm damage (adjusted damage) 4.7 % Boll damage 2.2 2.2 3.3 1.8 2.7 1.4 2.4+ 2.4- 0.23 0.12 0.84 BG BG BG WS WS WS BG II BG II BG II Conv. Conv. Conv.
Cotton Insect Corner (just Google) • 2010 insecticide rating chart (0 to 5) • Managing Stink Bugs in the Southeast