LSU AgCenter Department of Agronomy Valor and Velpar K4 Application Timing and Cane Tolerance Test Experiment number... : 01SC08JG Location... : St. Gabriel Research Station - St. Gabriel, LA Experimental design... : Randomized complete block Number of reps... : 4 Plot size... : 12 x 40 Row width/# per plot... : 72 /2 Soil type... : silt loam %OM... : 1.0 ph... : 5.9 Planting date... : 09-13-00 Harvest date... : 12-11-01 Crop/Variety... : Sugarcane/LCP85-384 (plant cane) Uniform std. treatment... : N/A Application type... : PRE POST1 POST2 Layby Date applied (mm/dd/yy)... : 04-04-01 04-12-01 05-02-01 05-16-01 Time (hh:mm-hh:mm)... : 12:00-4:00 pm 8:05-9:15 am 12:00-1:00 pm 2:45-3:00 pm Incorporation equipment... : N/A N/A N/A N/A Incorporation depth... : N/A N/A N/A N/A Air/Soil temperature (F)... : 85/77 80/67 89/72 94/77 Wind (mph, direction)... : 5/SW 5/S 6/S 1/S Cloud cover (%)... : 40 70 50 40 Relative humidity (%)... : 68 82 62 48 Soil/Leaf surface moist... : dry/dry dry/dry dry/dry dry/dry Crop stage/height... : 5-8" to collar 7-11 to collar 8-15" to collar 13-19 to collar Sprayer type/mph... : trctrca/3.75 bkpckco 2 /3.4 trctrca/3.75 trctrca/3.75 Nozzle type/size... : FF/8002VS FF/11002VS FF/8002VS FF/OC-04 Boom ht/#noz/sp. (in)... : 18 /3/36 18 /3/15 18 /3/12 40 /2/72 GPA/psi... : 20/33 20/32 20/33 10/28 Applied by... : Jones Siebert/Jones Jones Siebert Weed species (population) ---------(height/# leaves)----------- N/A Rainfall (in.) 0-24 hr/1-3 days... : 0.00/0.31 0.00/0.00 0.00/0.00 0.00/0.00 4-7 days/2nd week... : 2.29/0.00 0.00/2.05 0.38/0.00 0.19/0.00 3rd week/4th week... : 0.00/0.00 0.00/0.38 0.19/0.00 5.90/15.01
Comments: Injury ratings for April 27 were reflective of herbicide treatments applied on April 4 (PRE) and on April 12 (POST1). Significant injury was observed for Valor applied April 12 (20%), but injury for the same rate applied April 4 was 7%. Application of Regiment on April 12 injured sugarcane 44%. Injury was no more than 14% for the Velpar K4 treatments. For the May 29 rating date, sugarcane was injured when Valor was applied at POST2 27 days earlier (28%) and when Valor was applied twice on April 4 and at layby on May 16 (25%). Sugarcane injury at the May rating was 78% where Regiment was applied in mid-april. Sugarcane yield and sugar yield were significantly reduced when Valor was applied at POST1, POST2, or PRE followed by layby compared with only a PRE application. Even so, yields for these treatments were equal to the standard of Prowl + Karmex applied PRE in April and at layby in May. Sugarcane and sugar yields for the Velpar K4 treatments were also equal to the Prowl + Karmex standard. The excessive injury observed with Regiment resulted in a sugar yield reduction of 36% compared with the standard. Results clearly show that application of Valor over-the-top of sugarcane in mid-april should be avoided.
Cane Cane Cane Cane injury injury injury height % % % cm Trt Treatment Form Fm Rate Appl 04-16-01 04-27-01 05-29-01 09-13-01 No Name Amt Ds Rate Unit Code 12DAPRE 23DAPRE 27DAPRE 1 Prowl 3.3 EC 3.0 lb ai/a PRE 6 cd 7 de 9 cd 131.60 ab 2 Prowl 3.3 EC 3.0 lb ai/a PRE 31 a 20 b 16 c 130.65 ab Valor 50 WP 0.25 lb ai/a POST1 3 Prowl 3.3 EC 3.0 lb ai/a PRE 1 d 1 ef 28 b 128.57 abc Valor 50 WP 0.25 lb ai/a POST2 4 Prowl 3.3 EC 3.0 lb ai/a PRE 8 bcd 6 de 25 b 123.70 c Agridex L 10 % v/v PRE Valor 50 WP 0.25 lb ai/a Layby 5 Velpar K4 60 DF 2.4 lb ai/a PRE 14 bc 9 cd 3 d 130.38 ab 6 Atrazine 4 L 1.5 lb ai/a PRE 17 b 14 c 9 cd 129.77 ab Velpar K4 60 DF 2.4 lb ai/a POST1 7 Atrazine 4 L 1.5 lb ai/a PRE 3 d 0 f 13 c 129.45 ab Velpar K4 60 DF 2.4 lb ai/a POST2 8 Velpar K4 60 DF 2.4 lb ai/a PRE 10 bcd 6 de 8 cd 127.32 bc Velpar K4 60 DF 2.4 lb ai/a Layby
Cane Cane Cane Cane injury injury injury height % % % cm Trt Treatment Form Fm Rate Appl 04-16-01 04-27-01 05-29-01 09-13-01 No Name Amt Ds Rate Unit Code 12DAPRE 23DAPRE 27DAPRE 9 Prowl 3.3 EC 3.0 lb ai/a PRE 10 bcd 5 def 3 d 132.85 a 10 Prowl 3.3 EC 3.0 lb ai/a PRE 18 b 44 a 78 a 118.38 d Regiment 80 S 0.020 lb ai/a POST1 Kinetic L 0.125 % v/v POST1 Layby L 1.0 % v/v Layby LSD (P=.05) 9.5 5.0 7.4 4.700 Standard Deviation 6.6 3.4 5.1 3.239 CV 55.65 30.88 26.98 2.53 Replicate F 0.414 1.484 3.930 3.867 Replicate Prob(F) 0.7446 0.2419 0.0194 0.0201 Treatment F 7.302 55.715 76.215 7.013 Treatment Prob(F) 0.0001 0.0001 0.0001 0.0001
Cane Cane Cane yield TRS sugar yield Trt Treatment Form Fm Rate Appl ton/a lbs/ton lbs/a No Name Amt Ds Rate Unit Code 12-11-01 12-11-01 12-11-01 1 Prowl 3.3 EC 3.0 lb ai/a PRE 49.2 a 232 a 11397 a 2 Prowl 3.3 EC 3.0 lb ai/a PRE 45.2 b 209 b 9448 c Valor 50 WP 0.25 lb ai/a POST1 3 Prowl 3.3 EC 3.0 lb ai/a PRE 42.9 b 211 ab 9075 c Valor 50 WP 0.25 lb ai/a POST2 4 Prowl 3.3 EC 3.0 lb ai/a PRE 42.1 b 211 ab 8915 c Agridex L 10 % v/v PRE Valor 50 WP 0.25 lb ai/a Layby 5 Velpar K4 60 DF 2.4 lb ai/a PRE 50.1 a 222 ab 11118 ab 6 Atrazine 4 L 1.5 lb ai/a PRE 44.4 b 226 ab 10029 bc Velpar K4 60 DF 2.4 lb ai/a POST1 7 Atrazine 4 L 1.5 lb ai/a PRE 50.0 a 217 ab 10840 ab Velpar K4 60 DF 2.4 lb ai/a POST2 8 Velpar K4 60 DF 2.4 lb ai/a PRE 43.0 b 223 ab 9580 c Velpar K4 60 DF 2.4 lb ai/a Layby
Cane Cane Cane yield TRS sugar yield Trt Treatment Form Fm Rate Appl ton/a lbs/ton lbs/a No Name Amt Ds Rate Unit Code 12-11-01 12-11-01 12-11-01 9 Prowl 3.3 EC 3.0 lb ai/a PRE 48.9 a 206 b 10083 bc 10 Prowl 3.3 EC 3.0 lb ai/a PRE 30.1 c 214 ab 6429 d Regiment 80 S 0.020 lb ai/a POST1 Kinetic L 0.125 % v/v POST1 Layby L 1.0 % v/v Layby LSD (P=.05) 3.66 18.4 1155.6 Standard Deviation 2.52 12.7 796.4 CV 5.66 5.83 8.22 Replicate F 1.259 0.575 0.963 Replicate Prob(F) 0.3082 0.6363 0.4244 Treatment F 22.447 1.670 12.774 Treatment Prob(F) 0.0001 0.1455 0.0001