Progress 12/01/09 to 11/30/14
Outputs
Target Audience: Target audiences for this project include crop producers, crop consultants, crop advisors, agrichemical company representatives, county agents, extension specialists, and weed management professionals. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Graduate student education. How have the results been disseminated to communities of interest? Research results have been presented at professional meetngs, grower meetings, consultant training meetings, and field days. Data generated from research efforts serve as the basis for updating the Louisiana Suggested Chemical Weed Management Guide. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
In research to evaluate residual activity of herbicide/herbicide combinations, barnyardgrass control 24 days after rainfall activation (DAA) was as high as 31% for Valor, 100% for Prefix and Boundary, 53% for Tricor, 56% for Canopy DF, 45% for Envive, 99% for Zidua, 91% for Authority MTZ, and 100% for Authority Elite. Barnyardgrass was not controlled with Engenia. Control of hemp sesbania 24 DAA was greatest for Valor (86%) and Authority Elite (72%); pitted morningglory control was greatest for Authority Elite (84%); and prickly sida control was 94% or more for Valor, Canopy DF, and Envive. Engenia did not control pitted morningglory or prickly sida. Residual control out to 36 DAA was observed for pitted morningglory with Authority Elite and for prickly sida with Envive and Authority Elite. Dicamba-resistant soybeans were evaluated in anticipation for release to growers in 2016. Use of Extend (dicamba) preemergence and Extend or Engenia in combination with glyphosate postemergence provided effective weed control without crop injury. A dicamba drift study evaluated specific injury criteria to include soybean leaf cupping, crinkling, and soil contact; leaf petiole drooping and base swelling; terminal chlorosis, necrosis, and epinasty; and stem epinasty, swelling, and cracking 14 days after treatment. For each criterion, injury was quantified based on a scale of 0 to 5 with 0= no injury; 1= slight; 2= slight to moderate (producer concern); 3= moderate; 4= moderate to severe; 5= severe. Soybean yield was not reduced for dicamba applied at the lower levels of 1/1024, 1/512, and 1/256 of the use rate of 560 g ae/ha. Yield reduction for the intermediate levels of 1/128, 1/64, and 1/32 of the use rate was reduced around 10, 20, and 30%, respectively. For the intermediate rates, injury level was often variable between years and differentiating among the rates was difficult. For the higher rates of 1/16, 1/8, ¼, and ½ of the use rate, yield loss ranged from 33 to 100% and injury in most cases was moderate to severe. Data for specific injury criteria 15 days following dicamba application at V3/V4 were more variable compared with data collected for plant height reduction and overall visual injury assessment. Soybean height reduction was observed for the lower dicamba rates compared with the nontreated, but yield was not reduced. Although injury was moderate to severe for some of the injury criteria, soybeans were able to recover with only slight yield loss. Two-year average soybean height reduction associated with the higher dicamba rates of 40% or more and overall visual injury ratings of 75% or more were reflected in soybean yield loss of 30 to 100%. For data collected 14 days after dicamba application, soybean height reduction and overall visual injury ratings were better predictors of soybean yield loss compared with assessment of specific injury criteria based on severity. Harvest aid research in soybeans concentrated on saflufenacil as an alternative to paraquat. When applied prior to 65% leaf drop saflufenacil was less effective in desiccating soybean compared with paraquat. Neither herbicide was effective in desiccation of green stems.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Griffin, J.L., M.J. Bauerle, D.O. Stephenson, IV, D.K. Miller, and J.M. Boudreaux. 2013. Soybean response to dicamba applied at vegetative and reproductive growth stages. Weed Technol. 27:696703.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2013
Citation:
Orgeron, A. L., J.L. Griffin, B.L. Legendre, K.A. Gravois, D.K. Miller, and M.J. Pontif. 2013. Trinexapac-ethyl: Will it increase early season sugar accumulation? Proc. Int. Soc. Sugar Cane Technol. 28:1-11.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2013
Citation:
Bauerle, M. J., J. L. Griffin, R. Godara, J. L. Alford, A. B. Curry, III, and M. M. Kenty. 2014. Field evaluation of auxin herbicide volatility using tomato and cotton as bioassay crops. Weed Technol.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2013
Citation:
Fontenot, D. P., J.L. Griffin, and N. Baisakh. 2014. Growth comparisons and genetic diversity of bermudagrass (Cynodon dactylon) biotytpes in Louisiana. J. Am. Soc. Sugarcane Technol.
|
Progress 01/01/13 to 09/30/13
Outputs
Target Audience: Target audiences for this project include crop producers, crop consultants, crop advisors, agrichemical company representatives, county agents, extension specialists, and weed management professionals. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Two graduate students are being trained in field plot technique and pesticide application technologies. How have the results been disseminated to communities of interest? Data generated from research efforts served as the basis for updating the Louisiana Suggested Chemical Weed Management Guide. Research in the areas of herbicide application timing, efficacy of weed control programs, and weed interference was presented in three papers published in scientific journals. Presentations of research results were made to producers, consultants, and county agents through 14 meetings and field days. Research results in the areas of volatility of herbicide formulations, dicamba efficacy in weed control programs, harvest aid and fungicide program interactions, and bermudagrass interference were presented at professional meeting resulting in five abstracts. An electronic sugarcane newsletter was distributed several times during the year providing weed control recommendations and updates on herbicides and highlighting specific weed management programs and costs. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Twenty three herbicide/herbicide combinations were evaluated at four locations for residual weed control. Level of residual activity was affected by soil type and rainfall. Residual weed control was lowest for dicamba and greatest for sulfentrazone plus metolachlor. Excellent weed control was obtained in Roundup Ready and Liberty Link soybean when Envive or Canopy was applied PRE and followed by Roundup or Liberty plus Prefix or Zidua. Zidua continues to be effective when applied PRE alone or with other herbicides. Roundup Ready 2 Extend soybeans were evaluated for the third year in anticipation for release to growers in 2015. Use of Extend (dicamba) PRE or in combination with Roundup POST provided effective control of weeds without crop injury. A dicamba drift verification study provided further documentation of soybean injury associated with sub-lethal rates which will be valuable when dicamba-resistant soybean technology becomes available. Harvest aid research concentrated on Sharpen as an alternative to paraquat/Gramoxone. In sugarcane, Zidua and Mission (flazasulfuron) were investigated for weed control and crop response. Preliminary results show that sugarcane has good tolerance to both herbicides but neither controlled bermudagrass. Research also evaluated Sencor, Command, and other herbicides applied at planting and in the spring for bermudagrass control. Research also addressed fallow tillage/herbicide programs for bermudagrass. For bermudagrass collected from 13 outfield locations, ground cover 84 days after planting was less than 40% for biotypes J (Pointe Coupee Parish), N (Iberia Parish), and T (Tensas Parish), but greater than 80% for biotypes A (St. Martin Parish), C and D (St. Mary Parish), F (St. James Parish), Q (West Baton Rouge Parish), and R (Iberville Parish). Bermudagrass biotypes with the greatest plant height were A, B (Iberia Parish), E (St. John Parish), and Q, R, and S (Rapides Parish) (8.1 to 12.8 inches); plant height for biotype I (Terrebonne Parish) was 3.7 inches. Total dry weight over two years was greatest for biotype A and biotype Q; lowest dry matter yield was observed for biotypes J and T. Differences among the biotypes were also observed in sensitivity to glyphosate herbicide. Results also showed the ability of the sugarcane cultivars L 97-128, L 99-226, and HoCP 00-950 to rapidly produce shoot and root biomass which would enhance their competitiveness with bermudagrass. The cultivars, L 01-283, and L 03-371, which were slower to establish would be less competitive with bermudagrass. Allelopathy research failed to show any negative effect on sugarcane shoot and root growth when bermudagrass leachate was used as the sole water source. Squalene, a possible allelopathic compound, was identified in leachate collected from watering of bermudagrass.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Orgeron, A. L., J.L. Griffin, B. L. Legendre, and K.A. Gravois. 2013. Influence of nitrogen fertilization on sugarcane response to the ripeners glyphosate and trinexapac-Ethyl. J. Am. Soc. Sugarcane Technol. 33:30-37.
|
Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Research in the areas of herbicide application timing, efficacy of weed control programs, and weed interference was published in three scientific papers. Presentations of research results were made to producers, consultants, and county agents through 14 meetings and field days. Research results in the areas of volatility of herbicide formulations, dicamba efficacy in weed control programs, harvest aid and fungicide program interactions, and bermudagrass interference were presented at professional meetings resulting in five abstracts. An electronic sugarcane newsletter was distributed several times during the year providing weed control recommendations and updates on herbicides and highlighting specific weed management programs and costs. PARTICIPANTS: J.L. Griffin, (PI), B.J. Williams, J.P. Geaghan, D.K. Miller, J.E. Hanks, and E.P. Webster, Professors/Associate Professors; R.K. Godara, J.M. Ellis, and C.F. Grymes, Research Associates and Graduate Assistants, Louisiana State University Agricultural Center. TARGET AUDIENCES: Target audiences for this project include crop producers, crop consultants, crop advisors, agrichemical company representatives, county agents, extension specialists, and weed management professionals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
In volatility experiments, injury for tomato was 38% for 2,4-D ester, 14% for 2,4-D amine salt, 6% for 2,4-D acid, and 51% for triclopyr ester. Injury with dicamba amine salt formulations was 20% compared with 13% for the acid formulation. In soybean 28 days after application, dicamba applied preemergence at 1 lb/A controlled barnyardgrass and pitted morningglory 59 to 68%, prickly sida 81 to 90%, and redroot pigweed 84 to 90%. In another experiment, dicamba preemergence at 1 lb/A controlled barnyardgrass 66%, hemp sesbania 70%, prickly sida 61%, and redroot pigweed 63%. Preemergence control of hemp sesbania was improved when dicamba was applied with flumioxazin, metolachlor plus fomesafen, metribuzin, pyroxasulfone, and chlorimuron plus metribuzin and for redroot pigweed when dicamba was applied with pyroxasulfone. Prickly sida control was improved when dicamba was applied with metolachlor plus fomesafen, pyroxasulfone, and chlorimuron plus metribuzin and for pitted morningglory when dicamba was applied with pyroxasulfone and chlorimuron plus metribuzin. Pyroxasulfone applied preemergence at 0.133 lb/A controlled barnyardgrass 75%, pitted morningglory 73%, and hemp sesbania 61%. Control of these weeds was not improved when pyroxasulfone was applied with chlorimuron plus flumioxazin plus thifensulfuron, saflufenacil, or flumioxazin alone. Barnyardgrass control with pyroxasulfone was greater than for flumioxazin (75 vs. 59%), and hemp sesbania control with pyrxoxasulfone was greater than for flumioxazin and metribuzin plus sulfentrazone (61 vs. 40%). In sugarcane when metribuzin, clomazone plus diuron, pendimethalin plus metribuzin, and clomazone plus metribuzin were applied in mid-February, bermudagrass control 28 days after application was 33 to 68% and 10 to 40% 42 days after application. When herbicides were applied in mid-March, bermudagrass control with the herbicides was 38 to 75% 28 days after application and 30 to 58% 42 days after application. Sugarcane injury was greatest for clomazone plus diuron. Control of bermudagrass biotypes collected across the sugarcane belt with glyphosate ranged from 46 to 93%. In a bermudagrass interference study, the sugarcane cultivar HoCP 96-540 grown with 4 bermudagrass plants showed a 12 and 30% reduction in leaf length and collar height, respectively. Sugarcane tiller number was reduced at least 43%. Sugarcane root weight grown with two bermudagrass plants was reduced 50%. In the cultivar experiment based on sugarcane shoot weight, the cultivars L 99-226 and L 97-128 were more competitive with bermudagrass than L 01-283 and HoCP 96-540. Sugarcane root weight for L 99-226 and L 97-128 was equivalent and averaged 1.9 times that for HoCP 00-950, L 03-371, L 01-283, and HoCP 96-540. Averaged across cultivars, two bermudagrass plants per pot reduced sugarcane shoot weight 17% and sugarcane root weight 14%.
Publications
- Griffin, J.L., P.A. Clay, J.M. Ellis, D.K. Miller, C.F. Grymes, and J.E. Hanks. 2012. Bermudagrass (Cynodon dactylon) control in sugarcane with glyphosate and a hooded sprayer. J. Am. Soc. Sugarcane Technol. 32:38-50.
- Godara, R.K., B.J. Williams, E. P. Webster, J.L. Griffin, and D.K. Miller. 2012. Evaluation of imazosulfuron for broadleaf weed control in drill-seeded rice. Weed Technol. 26:19-23.
- Godara, R.K., B.J. Williams, E. P. Webster, J.L. Griffin, and J.P. Geaghan. 2012. Texasweed (Caperonia palustris) interference in drill-seeded rice. Weed Technol. 26:356-363.
|
Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: Research in the areas of application timing of harvest aids and efficacy and economics of weed control programs was presented in three papers published in scientific journals. Presentations of results were made to producers, consultants, and county agents through 15 meetings and field days. Research in the areas of soybean response to dicamba, efficacy and economics of fallow programs for sugarcane, weed management programs in sugarcane, and the value of harvest aids in soybean IPM programs were presented at professional meetings resulting in five abstracts. An electronic sugarcane newsletter was distributed several times during the year providing weed control recommendations and updates on herbicides and highlighting specific weed management programs and costs. PARTICIPANTS: J.L. Griffin, (PI), C.d. Blouin, D.K. Miller, R.P. Strahan, M.E. Salassi, J.S. Beasley, J.M. Boudreaux, J. Taverner, S.M. Borst, and J. Mite, LSU AgCenter. TARGET AUDIENCES: Target audiences for this project include crop producers, crop consultants, crop advisors, agrichemical company representatives, county agents, extension specialists, and weed management professionals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
A johnsongrass population in Pointe Coupee Parish was confirmed as resistant to glyphosate. To obtain 50% control required a rate 10.2 times that of the normal glyphosate rate; for 95% control a rate 40 times that of the normal rate would be required. In soybean, preemergence control of hemp sesbania was greatest for flumioxazin plus cloransulam-methyl and flumioxazin plus pyroxasulfone (around 80%); morningglory control was greatest for chlorimuron plus flumioxazin plus thifensulfuron, flumioxazin plus chlorimuron, flumioxazin plus cloransulam-methyl, and flumioxazin plus pyroxasulfone (around 90%). Dicamba provided excellent weed control when applied preemergence and when applied postemergence in combination with glyphosate in dicamba-tolerant soybean. Dicamba improved preemergence control of hemp sesbania when applied with flumioxazin, flumioxazin plus chlorimuron ethyl, acetochlor plus flumioxazin, sulfentrazone plus metribuzin, metribuzin, and chlorimuron plus metribuzin (82 to 98%) and when applied with s-metolachlor plus fomesafen, s-metolachlor, acetochlor, and pyroxasulfone (73 to 78%). Prickly sida control was improved when dicamba was applied with s-metolachlor plus fomesafen, s-metolachlor, acetochlor, sulfentrazone plus metribuzin, and pyroxasulfone. Pyroxasulfone applied preemergence and postemergence was ineffective on hemp sesbania and morningglory and injurious to soybeans. In sugarcane, postemergence control of johnsongrass six weeks after treatment (WAT) was 53% with thiencarbazone-methyl plus isoxaflutole, 32% with tembotrione, 45% with thiencarbazone-methyl plus tembotrione, 12% with mesotrione, and 75% with asulam plus trifloxysulfuron. Sugarcane injury was significant for thiencarbazone-methyl plus isoxaflutole and tembotrione. When metribuzin, clomazone plus diuron, pendimethalin plus metribuzin, and clomazone plus metribuzin were applied in mid-February, bermudagrass control 4 WAT was 33 to 68% and 10 to 40% 6 WAT. When applied in mid-March, bermudagrass control 4 WAT with the herbicides was 38 to 75% and 30 to 58% 6 WAT. Sugarcane injury was greatest for clomazone plus diuron. Fallow season programs for bermudagrass control were implemented during the summer of 2010 and included various combinations of bottom plowing, disking, chisel plow, and re-hipping of beds coupled with single or multiple applications of glyphosate. For the sugarcane crop the following year, no-differences in stalk population and yield among the fallow treatments were observed. For bermudagrass plants collected at 20 locations across the sugarcane belt, control with glyphosate ranged from 46 to 93%. Considerable differences among biotypes in growth rate and growth characteristics were observed. Halosulfuron, halosulfuron plus dicamba, sulfentrazone plus metribuzin, and trifloxysulfuron were applied postemergence in October to sugarcane and purple nutsedge. Four weeks after application control for all treatments was equivalent and ranged from 56 to 68%. Sugarcane injury was 25% for sulfentrazone plus metribuzin, but no more than 9% for the other treatments.
Publications
- Boudreaux, J.M. and J.L. Griffin. 2011. Application timing of harvest aid herbicides affects soybean harvest and yield. Weed Technol. 25:38-43.
- Mite Caceres, J.R., J.L. Griffin, M.E. Salassi, and J.M. Boudreaux. 2011. Efficacy and economics of EPTC in fallowed sugarcane fields. J. Am. Soc. Sugarcane Technol. 31:25-38.
- Taverner, J., J.S. Beasley, R.E. Strahan, J.L. Griffin, and S.M. Borst. 2011. Selective postemergence herbicide control of torpedograss in centipedegrass. Weed Technol. 25:212-216.
|
Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Research in the areas of weed biology, weed/crop competition, weed management, and herbicide harvest aids was presented in six papers published in scientific journals. Presentations of research results were made to producers, consultants, and county agents through 21 meetings and field days. Research results in the areas of growth characteristics and shading ability of sugarcane cultivars, weed response to shading, weed management programs in sugarcane, and the value of harvest aids in soybean IPM programs were presented at professional meeting resulting in five abstracts. An electronic sugarcane newsletter was distributed several times during the year providing weed control recommendations and updates on herbicides and highlighting specific weed management programs and costs. PARTICIPANTS: J.L. Griffin, Principal Investigator; C.D. Blouin, D.K. Miller, and R.P. Strahan, Professors/Associate Professors; J.M. Boudreaux, L.M. Etheredge, Jr., C.A. Jones, K.R. LeJeune, M. Bittencourt, and J. Mite, Research Associates and Graduate Assistants, Louisiana State University Agricultural Center. TARGET AUDIENCES: Target audiences for this project include crop producers, crop consultants, crop advisors, agrichemical company representatives, county agents, extension specialists, and weed management professionals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Valor SX (flazasulfuron), Prefix (s-metolachlor plus fomesafen), Authority MTZ (sulfentrazone plus metribuzin), Sencor (metribuzin), and Canopy (chlorimuron plus metribuzin) applied preemergence and followed by glyphosate in Roundup Ready soybeans and followed by Liberty (glufosinate) in Liberty Link soybeans provided effective grass and broadleaf weed control. Liberty applied with Flexstar (fomesafen), Ultra Blazer (acifluorfen), or Classic (chlorimuron) was no more effective than Liberty applied alone twice. Dicamba, which will be used in the future in dicamba-resistant soybeans, provided good control of morningglories, hemp sesbania, prickly sida, and other weeds. Dicamba was very injurious to soybean and significant yield reductions occurred when applied at vegetative and reproductive growth stages. Johnsongrass collected from a soybean field in Erwinville, LA, was confirmed as resistant to glyphosate. Gramoxone Inteon (paraquat) harvest aid research determined the appropriate application timing and the value of harvest aid when used in a program with fungicide application and stinkbug control. In a non-crop area with heavy rhizome johnsongrass pressure, rhizome johnsongrass was controlled 86% with Corvus (thiencarbazone-methyl and isoxaflutole) and 81% with Capreno (thiencarbazone-methyl and tembotrione) applied preemergence. Capreno, Laudis (tembotrione), and Callisto (mesotrione) controlled johnsongrass postemergence 85, 76, and 38%, respectively. Sugarcane was not injured with Corvus and Capreno but injury was significant for Capreno and Laudis. Formulations of 2,4-D and dicamba were evaluated for volatility and potential off-target movement. The acid formulations of 2,4-D (Unison) and dicamba (Vision) were less injurious to sensitive crops compared with salt formulations. In sugarcane, flazasulfuron was applied over-the-top alone and with trifloxysulfuron to evaluate johnsongrass control and crop injury. Sugarcane showed very good tolerance to flazasulfuron and johnsongrass control was comparable to that for asulam or asulam plus trifloxysulfuron. Fallow programs for bermudagrass control included various combinations of bottom plowing, disking, chisel plow, and re-hipping of beds along with single or multiple applications of glyphosate. Preliminary indications are that bottom plowing may reduce bermudagrass infestation. Treatments will be monitored in the plant cane crop. A spreadsheet decision aid was developed that summarizes sugarcane fallow field operations and weed control costs, including equipment used, performance rates, and herbicides applied. These data can be entered by the user for specific farm situations, calculating total variable tillage and weed control costs per acre.
Publications
- Jones, C.A. and J.L. Griffin. 2010. Red morningglory (Ipomoea coccinea) response to tillage and shade. J. Am. Soc. Sugarcane Technol. 30:11-20.
- Griffin, J.L., J.M. Boudreaux, and D.K. Miller. 2010. Herbicides as harvest aids. Weed Sci. 58:355-358.
- Bittencourt, M., J.L. Griffin, J.M. Boudreaux, and D.C. Blouin. 2010. Seasonal growth, shading potential, and yield of six sugarcane cultivars. J. Am. Soc. Sugarcane Technol. 30:21-36.
- Etheredge, L.M., Jr., J.L. Griffin, and J.M. Boudreaux. 2010. Nutsedge (Cyperus spp.) control programs in sugarcane. J. Am. Soc. Sugarcane Technol. 30:67-80.
- Griffin, J.L., R.P. Strahan, D.K. Miller, and K.R. LeJeune. 2010. Tillage effects on itchgrass seedling emergence and changes in the seed soil reservoir. J. Am. Soc. Sugarcane Technol. 30:81-88.
- Etheredge, L.M., Jr., J.L. Griffin, and J.M. Boudreaux. 2010. Purple nutsedge (Cyperus rotundus) competition with sugarcane and response to shade. J. Am. Soc. Sugarcane Technol. 30:89-103.
|
|