Efficacy of Sodium Chloride Applications for Control of Goosegrass (Eleusine indica) in Seashore Paspalum Turf

Transcription

1 Weed Technology : Efficcy of Sodium Chloride Applictions for Control of Goosegrss (Eleusine indic) in Seshore Psplum Turf Jmes T. Brosnn, Joseph DeFrnk, Mich S. Woods, nd Greg K. Breeden* Control of goosegrss is difficult in the pn-pcific region. No hericides re currently leled for selective control of goosegrss in seshore psplum turf, species used regulrly on golf courses throughout the tropics. Sequentil grnulr pplictions of sodium chloride (99% sodium chloride, 1% sodium silicoluminte, 83% 0.5 to 0.25 mm dim) t kg/h did not effectively (. 70%) control goosegrss in this study. Goosegrss injury following sequentil grnulr pplictions of sodium chloride, t kg/h, susided t 6 wk fter initil tretment (WAIT). A single ppliction of MSMA t 2.40 kg/h plus metriuzin t kg/h provided 96 nd 83% control of goosegrss 8 WAIT in 2007 nd 2008, respectively. Sequentil pplictions of MSMA plus metriuzin t lower rtes yielded similr results. Applictions of formsulfuron did not effectively control (. 70%) goosegrss in this study, suggesting possile tolernce to this tretment. Applictions of MSMA plus metriuzin controlled goosegrss (. 70%), ut induced phytotoxic injury to seshore psplum turf. Additionl reserch is needed to evlute strtegies for POST control of goosegrss in seshore psplum turf tht do not induce phytotoxic turfgrss injury fter ppliction. Nomenclture: Metriuzin; MSMA; formsulfuron; goosegrss, Eleusine indic (L.) Gertn. ELEIN; seshore psplum, Psplum vgintum Swrtz. PASVA. Key words: Slinity, turfgrss, chlorophyll meter, chlorophyll index, seshore psplum, hericide, weed. Goosegrss is one of the most difficult turfgrss weeds to control in the tropicl nd sutropicl pn-pcific region (Wiecko 2000). A summer nnul in temperte regions, goosegrss ehves s perennil in tropicl nd sutropicl environments, producing new tillers during every month of the yer. Environmentl conditions in the pn-pcific region lso llow for the yer-round germintion of goosegrss seed; thus, popultions t vrious stges of growth re present throughout the yer. Considering tht hericides leled for POST goosegrss control re often more efficcious when pplied to nontillering plnts, vriility in goosegrss growth stge often mkes POST hericide pplictions less effective in tropicl climtes (R. Nishimoto, personl communiction). Options for selective POST control of goosegrss in turf include pplictions of metriuzin plus MSMA (Brennn et l. 1992; Nishimoto nd Murdoch 1999), simzine plus MSMA (Murdoch nd Iked 1974), diclofop (McCrty 1991), diclofop plus metriuzin (Nishimoto nd Murdoch 1999), formsulfuron (Nishimoto nd Kwte 2003), nd formsulfuron plus metriuzin (Busey 2004). Although these products re sfe for use on ermudgrss turf (Cynodon spp.), none re leled for use on seshore psplum, turfgrss used extensively on golf courses throughout Hwii for its esthetic chrcteristics nd slinity tolernce. Although morphologiclly nd estheticlly similr to ermudgrss, seshore psplum cn tolerte slinity levels s high s 54 ds/m, DOI: /WT * First nd second uthors: Assistnt Specilist Turfgrss Mngement, Professor Weed Science, Deprtment of Tropicl Plnt nd Soil Sciences, University of Hwii, 3190 Mile Wy #102, Honolulu, HI 96822; third uthor: President, Asin Turfgrss Center, 77/1 Moo 3 Bngplee, Bngsi Ayuddhy 13190, Thilnd; fourth uthor: Weed Science Extension Assistnt, Deprtment of Plnt Sciences, University of Tennessee, 252 Ellington Plnt Sciences Building, 2431 Joe Johnson Drive, Knoxville, TN Current ddress of first uthor: Deprtment of Plnt Sciences, University of Tennessee, 252 Ellington Plnt Sciences Building, 2431 Joe Johnson Drive, Knoxville, TN Corresponding uthor s E-mil: jrosnn@utk.edu level t which most horticulturl crops could not survive (Duncn nd Crrow 2000). Reserch hs suggested tht this slinity tolernce might llow for pplictions of sodium chloride to e used for POST control of grssy weeds in seshore psplum (Duncn nd Crrow 2000). Slt-tolernt turfgrsses like seshore psplum re le to mke osmotic djustments following slt stress (Mrcum nd Murdoch 1990), wheres certin weed species cnnot. Brosnn et l. (2008) suggested tht grnulr pplictions of sodium chloride could crete osmotic grdients lrge enough to rupture the cell memrnes of some grssy weed species in mnner similr to wht hs een reported fter pplictions of metriuzin nd MSMA. Reserch investigting the efficcy of sodium chloride pplictions for POST control of goosegrss in seshore psplum is limited. Wiecko (2003) reported tht six sequentil pplictions of sline ocen wter (electricl conductivity [EC] 5 55 ds/m) induced severe (. 90%) phytotoxic injury to goosegrss plnts 10 d fter initil tretment (DAIT); however, injury decresed to lmost 48% t 30 DAIT. Pool et l. (2005) reported tht pplictions of 54 ds/m sline wter provided greter thn 70% control of goosegrss in greenhouse study. Brosnn et l. (2008) suggested tht sequentil pplictions of sodium chloride t kg/h re required for POST control of grssy weeds nd tht crrier volumes required to deliver rtes s lrge s kg/h render commercil spry pplictions imprcticl. In the sme study, Brosnn et l. (2008) reported tht sequentil pplictions of grnulr sodium chloride t kg/h provided greter thn 90% control of sourgrss (Psplum conjugtum Berg.) in seshore psplum turf. The efficcy of grnulr pplictions of sodium chloride for POST control of goosegrss in seshore psplum hs not een investigted. The ojective of this reserch ws to determine the efficcy of grnulr pplictions of sodium Brosnn et l.: Sodium Chloride for Control of Goosegrss N 179

2 chloride for POST control of goosegrss in seshore psplum turf. Mterils nd Methods Studies were conducted on Slm seshore psplum driving rnge tee t Corl Creek Golf Course (Ew Bech, HI) in Octoer 2007 nd Slm seshore psplum turfgrss stnd t Kpiolni Prk (Honolulu, HI) in Jnury Seshore psplum turfgrss t Corl Creek ws estlished on Mml stony, silty, cly lom soil (clyey, prsesquic, isohyperthermic Lithic Hplocmids), wheres seshore psplum turfgrss t Kpiolni Prk ws estlished on Jucs snd soil (crontic, isohyperthermic Typic Ustipsmments). Turfgrss ws mintined t 3.8 cm height t ech fcility. Plot size ws 2.1 y 0.9 m. Soil testing efore initition of ech experiment reveled no nutrient deficiencies t either site nd soil ph vlues of 7.3 nd 7.5, respectively. Rinfll in ech experiment ws monitored with virtul wether sttion mnged y ZedX Inc. (Bellefonte, PA). s were s follows: (1) grnulr sodium chloride 1 t kg/h, followed y grnulr sodium chloride t kg/h 7 d lter, followed y grnulr sodium chloride t kg/h 7 d lter; (2) MSMA 2 t kg /h, followed y MSMA t kg /h 14 d lter; (3) MSMA t 2.4 kg /h; (4) MSMA t kg/h plus metriuzin 3 t kg/h, followed y MSMA t kg/h plus metriuzin t kg/h 14 d lter; (5) MSMA t 2.4 kg/h plus metriuzin t kg/h; (6) formsulfuron 4 t kg/h followed y formsulfuron t kg/h 14 d lter; (7) formsulfuron t kg/h; (8) untreted check. The MSMA formultion evluted included surfctnt. The grnulr sodium chloride tretment ws pplied from shker jr. All other tretments were pplied y CO 2 -powered oom spryer clirted to deliver 374 L/h with one flt-fn 8004E nozzle t 275 kp configured to provide 0.9-m spry swth. s were initited on Octoer 9, 2007 t Corl Creek nd Jnury 23, 2008 t Kpiolni Prk. Plots were rted 1, 2, 3, 6, nd 8 wk fter initil tretment (WAIT). The percentge of goosegrss in ech plot ws determined visully, with chnges in the percentge of goosegrss in ech plot used to clculte percent control; greter thn 70% control ws considered cceptle. Seshore psplum nd goosegrss injury were ssessed quntittively through mesurements of reltive chlorophyll index (R840/R700) with CM-1000 chlorophyll meter 5 ccording to the methods of Mngifico nd Guillrd (2005). The CM-1000 chlorophyll meter mesures chlorophyll content y nlyzing mient nd reflected light t two wvelengths (700 nd 840 nm); results re expressed on reltive index of 0 (no chlorophyll present) to 999 (mximum mesurle chlorophyll content). This device hs een used y other reserchers to quntify hericide injury (Teuton et l. 2008). One soil core (10 y 8.9 y 1.9 cm) ws removed from ech plot t 8 WAIT nd nlyzed for sodium dsorption rtio (SAR) nd electricl conductivity (EC e ) ccording to the methods of Sprks (1996). Voids remining fter cores were removed were filled with silic snd. The experimentl design ws rndomized complete lock with three replictions. Dt were sujected to nlysis of vrince. Fisher s protected LSD vlues re reported for comprisons t the level. Significnt interctions were detected etween yers nd tretments; thus, dt from ech yer re presented individully. Results nd Discussion Sodium Chloride s. Grnulr pplictions of sodium chloride did not effectively (. 70%) control goosegrss in this study. Sequentil pplictions of grnulr sodium chloride t kg/h (tretment 1) provided 58 nd 54% control of goosegrss 8 WAIT in 2007 nd 2008, respectively (Tle 1). This response differs from wht ws reported y Brosnn et l. (2008) evluting the use of grnulr sodium chloride pplictions for sourgrss (Psplum conjugtum Berg.) control. However, sequentil grnulr pplictions of sodium chloride t kg/h (tretment 1) induced phytotoxic injury to goosegrss plnts. Goosegrss chlorophyll index vlues 1, 2, nd 3 WAIT in 2008 mesured 181, 109, nd 146 for tretment 1, respectively, compred with 250, 213, nd 246, respectively, for the untreted check (Tle 2). A similr response ws oserved in 2007 s well. Similr to the findings of Wiecko (2003), injury susided 30 d fter tretment, in tht goosegrss chlorophyll index vlues were not sttisticlly different from the untreted check t 6 nd 8 WAIT in oth 2007 nd 2008 (Tle 2). In oth 2007 nd 2008, sequentil pplictions of grnulr sodium chloride t kg/h (tretment 1) yielded soil SAR vlues tht were higher thn the untreted check; tretment 1 yielded n SAR vlue of 3.3 in 2007 nd 2008, compred with vlues of 1.4 nd 1.2, respectively, for the untreted check (Tle 3). Similr to wht ws reported y Brosnn et l. (2008), SAR vlues in this study re well elow threshold levels tht would negtively ffect seshore psplum turfgrss qulity. Sequentil pplictions of grnulr sodium chloride t kg/h (tretment 1) hd no effect on soil EC e vlues in this study. Hericide s. Sequentil pplictions of MSMA plus metriuzin effectively (. 70%) controlled goosegrss in this study. Applictions of MSMA t kg/h plus metriuzin t kg/h, followed y MSMA t kg/h plus metriuzin t kg/h 14 d lter (tretment 4) provided 92 nd 77% control of goosegrss 8 WAIT in 2007 nd 2008, respectively (Tle 1). A similr response ws oserved fter single ppliction of MSMA plus metriuzin t rtes of 2.40 nd kg/h (tretment 5), respectively, in oth 2007 nd 2008 (Tle 1). Goosegrss control following pplictions of MSMA plus metriuzin hs een reported y other reserchers (Brennn et l. 1992; Busey 2004; Johnson 1980; Nishimoto nd Murdoch 1999). Applictions of formsulfuron (tretments 6 nd 7) did not effectively (. 70%) control goosegrss in this study. Goosegrss tolernce to pplictions of formsulfuron hs een oserved in Hwii, with tolernt goosegrss popultions exhiiting sensitivity to pplictions of MSMA plus metriu- 180 N Weed Technology 23, Jnury Mrch 2009

3 Tle 1. Goosegrss control mens for sodium chloride nd hericide tretments in 2007 nd Goosegrss control 1 WAIT 2 WAIT 3 WAIT 6 WAIT 8 WAIT 1. Grnulr sodium chloride + grnulr sodium chloride (7 d lter) + grnulr sodium chloride (7 d lter) kg/h % MSMA+ MSMA (14 d lter) MSMA MSMA+ metriuzin + MSMA (14 d lter) + metriuzin (14 d lter) MSMA + metriuzin Formsulfuron + formsulfuron (14 d lter) Formsulfuron Untreted check LSD (0.05) NS NS Arevitions: NS 5 not significnt t the level; WAIT 5 weeks fter initil tretment. Visul ssessment of the chnge in percentge of goosegrss per plot. zin (Brosnn et l. 2008; J. DeFrnk, personl communiction). Busey (2004) oserved goosegrss response to pplictions of formsulfuron lone to e quite vrile; t only two out of five experimentl sites did pplictions of formsulfuron lone provide greter thn 68% goosegrss control. Goosegrss popultions tht hve developed tolernce to formsulfuron re sensitive to tnk-mix pplictions of MSMA nd metriuzin ( J. DeFrnk, personl communiction). Dt collected in this study supports these oservtions, in tht single ppliction of MSMA t 2.40 kg/h plus metriuzin t kg/h provided 96 nd 83% control of goosegrss 8 WAIT in 2007 nd 2008, respectively, wheres single ppliction of formsulfuron t kg/h only provided 58 nd 63% control 8 WAIT in 2007 nd 2008, respectively (Tle 1). Hericide tretments tht effectively (. 70%) controlled goosegrss in this study injured seshore psplum turf for 3 WAIT in oth 2007 nd Seshore psplum chlorophyll index vlues fter n ppliction of MSMA t 2.40 kg/h plus metriuzin t kg/h (tretment 5), were Tle 2. Goosegrss chlorophyll index vlues for sodium chloride nd hericide tretments in 2007 nd Goosegrss chlorophyll index 1 WAIT 2 WAIT 3 WAIT 6 WAIT 8 WAIT 1. Grnulr sodium chloride + grnulr sodium chloride (7 d lter) + grnulr sodium chloride (7 d lter) kg/h R840/R MSMA + MSMA (14 d lter) MSMA MSMA + metriuzin + MSMA (14 d lter) + metriuzin (14 d lter) MSMA + metriuzin Formsulfuron + formsulfuron (14 d lter) Formsulfuron Untreted check LSD (0.05) Reltive chlorophyll index mesured t two wvelengths 840 nd 700 nm (R840/R700) ccording to the methods of Mngifico nd Guillrd (2005). Arevition: WAIT 5 weeks fter initil tretment. Brosnn et l.: Sodium Chloride for Control of Goosegrss N 181

4 Tle 3. Soil sodium dsorption rtio (SAR) nd electricl conductivity mens 8 weeks fter initil tretment for sodium chloride nd hericide tretments in 2007 nd Sodium dsorption rtio Electricl conductivity Grnulr sodium chloride + grnulr sodium chloride (7 d lter) + grnulr sodium chloride (7 d lter) kg/h SAR ds/m MSMA + MSMA (14 d lter) MSMA MSMA + metriuzin + MSMA (14 d lter) + metriuzin (14 d lter) MSMA + metriuzin Formsulfuron + formsulfuron (14 d lter) Formsulfuron Untreted check LSD (0.05) NS NS Soil SAR nd electricl conductivity mesured ccording to the methods of Sprks (1996). Arevition: NS 5 not significnt t the level. 139, 162, nd 217 compred with 316, 335, nd 358 for the untreted check t 1, 2, nd 3 WAIT, respectively, in 2007 (Tle 4). Similr responses were oserved fter pplying this tretment in 2008 nd fter sequentil pplictions of MSMA plus metriuzin t lower rtes (tretment 4) in oth 2007 nd These results support the findings of Busey (2004) nd Duncn nd Crrow (2000), who reported tht pplictions of MSMA plus metriuzin t similr rtes cn injure oth Tifwy hyrid ermudgrss (Cynodon dctylon 3 Cynodon trnsvlensis) nd seshore psplum turf. Additionl reserch is needed to evlute strtegies for POST control of goosegrss in seshore psplum turf tht do not induce significnt phytotoxic turfgrss injury fter ppliction. Sources of Mterils 1 Grnulr sodium chloride, Morton Interntionl Inc., Chicgo, IL MSMA 6 Plus, Drexel Chemicl Inc., Memphis, TN Tle 4. Seshore psplum chlorophyll index vlues for sodium chloride nd hericide tretments in 2007 nd Seshore psplum chlorophyll index 1 WAIT 2 WAIT 3 WAIT 6 WAIT 8 WAIT 1. Grnulr sodium chloride + grnulr sodium chloride (7 d lter) + grnulr sodium chloride (7 d lter) kg/h R840/R MSMA + MSMA (14 d lter) MSMA MSMA + metriuzin + MSMA (14 d lter) + metriuzin (14 d lter) MSMA + metriuzin Formsulfuron + formsulfuron (14 d lter) Formsulfuron Untreted check LSD (0.05) Reltive chlorophyll index mesured t two wvelengths 840 nd 700 nm (R840/R700) ccording to the methods of Mngifico nd Guillrd (2005). Arevition: WAIT 5 weeks fter initil tretment. 182 N Weed Technology 23, Jnury Mrch 2009

5 3 Sencor 75DF, Byer Environmentl Sciences, Reserch Tringle Prk, NC Revolver 0.19SC, Byer Environmentl Sciences, Reserch Tringle Prk, NC CM-1000 chlorophyll meter, Spectrum Technologies Inc., Est Plinfield, IL Acknowledgments The uthors thnk Mr. Kyun Kim, golf course superintendent t Corl Creek Golf Course, nd Mr. Ed Freits of the Honolulu Prks Deprtment for their ssistnce in this reserch. Mention of products or trde nmes do not constitute endorsement y the University of Tennessee nd re included s reference only. These products should e used in ccordnce with the mnufcturers instructions. Literture Cited Brennn, B. M., A. K. Higshi, nd C. L. Murdoch Estimted Pesticide Use on Golf Courses in Hwii. Honolulu, HI: Hwii Institute of Tropicl Agriculture nd Humn Resources Reserch Extension Series p. Brosnn, J. T., J. DeFrnk, M. S. Woods, nd G. K. Breeden Sodium chloride slt pplictions provide effective control of sourgrss (Psplum conjugtum Berg.) in seshore psplum (Psplum vgintum Swrtz.) turf. Weed Technol. (under review; sumitted 4 Septemer 2008). Brosnn, J. T., R. K. Nishimoto, nd J. DeFrnk Metriuzin-resistnt goosegrss (Eleusine indic L.) in ermudgrss (Cynodon spp. L.) turf. Weed Technol 22: Busey, P Goosegrss (Eleusine indic) control with formsulfuron in ermudgrss (Cynodon spp.). Weed Technol. 18: Duncn, R. R. nd R. N. Crrow Seshore Psplum: The Environmentl Turfgrss. Chelse, MI: Ann Aror Press. Pp. 4, Johnson, B. J Goosegrss (Eleusine indic) control in Bermudgrss (Cynodon dctylon) turf. Weed Technol. 28: Mngifico, S. S. nd K. Guillrd Turfgrss reflectnce mesurements, chlorophyll, nd soil nitrte desored from nion exchnge memrnes. Crop Sci. 45: Mrcum, K. B. nd C. L. Murdoch Growth responses, ion reltions, nd osmotic dpttions of eleven C4 turfgrsses to slinity. Agron. J. 82: McCrty, L. B Goosegrss (Eleusine indic) control in ermudgrss (Cynodon spp.) turf with diclofop. Weed Technol. 39: Murdoch, C. L. nd D. Iked Goosegrss control in ermudgrss turf with comintions of MSMA with s-trizines. Agron J. 66: Nishimoto, R. K. nd M. K. Kwte Revolver effective for goosegrss. Hwii Lndsc. 7(4):7. Nishimoto, R. K. nd C. L. Murdoch Mture goosegrss (Eleusine indic) control in ermudgrss (Cynodon dctylon) turf with metriuzin-diclofop comintion. Weed Technol. 13: Pool, N. B., B. J. Brecke, J. B. Unruh, G. E. McDonld, L. E. Trenholm, nd J. A. Ferrell Mnging weeds in seshore psplum using sline irrigtion. Presented t the Florid Weed Science Society 28th Annul Meeting, Ferury 2005, Lke Alfred, FL. [Astrct] FWSS%20wepge-2005%20Sept-A&M.htm. Sprks, D. L Methods of Soil Anlysis: Prt 3 Chemicl Methods. Mdison, WI: Soil Science Society of Americ Book Series Numer 5. Teuton, T. C., C. L. Min, J. C. Sorochn, J. S. McElroy, W. E. Hrt, C. E. Sms, nd T. C. Mueller Hyrid Kentucky luegrss tolernce to preemergence nd postemergence hericides. Weed Technol. 22: Wiecko, G Sequentil hericide tretments for goosegrss control in ermudgrss (Cynodon dctylon) turf. Weed Technol. 14: Wiecko, G Ocen wter s sustitute for postemergence hericides in tropicl turf. Weed Technol. 17: Received Septemer 4, 2008, nd pproved Novemer 3, Brosnn et l.: Sodium Chloride for Control of Goosegrss N 183