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1 This Journl of Environmentl Hortiulture rtile is reprodued with the onsent of the Hortiulturl Reserh Institute (HRI whih ws estlished in 96 s the reserh nd development ffilite of the Amerin Nursery & Lndspe Assoition (ANLA HRI s Mission: To diret, fund, promote nd ommunite hortiulturl reserh, whih inreses the qulity nd vlue of ornmentl plnts, improves the produtivity nd profitility of the nursery nd lndspe industry, nd protets nd enhnes the environment. The use of ny trde nme in this rtile does not imply n endorsement of the equipment, produt or proess nmed, nor ny ritiism of ny similr produts tht re not mentioned. Copyright, All Rights Reserved

2 Plnt Suseptiility to nd Sesonl Ourrene of Phedon desotonis Blsugh, Lef Beetle Attking Coreopsis S. Kris Brmn, Andrew Pendley nd Will Corley Deprtment of Entomology, University of Georgi College of Agriulturl nd Environmentl Sienes Georgi Experiment Sttion, Griffin, GA 33 Astrt Phedon desototonis Blsugh, lef eetle, ourred in lrge numers in plntings of wildflowers in entrl Georgi. Although the speies ws previously onsidered rre, lrge popultions of the eetle were ssoited with Coreopsis spp. Pek lrvl undne ourred in April, while gretest numers of dults were oserved in My. One genertion ws oserved. Thirty-eight plnt tx in fmilies were evluted for suseptiility to feeding nd injury y the eetle. The omposits Coreopsis lneolt (L.), Coreopsis tintori Nuttll, C. vertiillt (L.), nd Bidens ristos (L.) were onsistently fed on y dults nd lrve of P. desotonis. Of those plnts, B. ristos ws the lest preferred nd lest dmged. Index words: lef eetle, Chrysomelide, Coreopsis, pest mngement, plnt suseptiility. Speies used in this study: Ahille millefolium L., Aquilegi erule Jmes, Aster levis L. Per., Bidens ristos (L.), Brssi npis Iris, Brssi npis Flon, Cssi fsiult Mihux, Centure ynus L., Cerstium ierersteinii DC., Chrysnthemum leunthemum L., Conslid migu (L.) P.W. Bll & Heywood, Coreopsis lneolt L., Coreopsis tintori Nuttll, C. vertiillt (L.), Dinthus deltoides L., Ehine purpure (L.) Moenh., Eshsholzi liforni Chmisso, Euptorium olestinum L., Gillrdi ristt Pursh, Gillrdi pulhell Fougeroux de Bondroy, Loulri mritim (L.) Desv., Monrd itriodor Cervntes ex Lgsk y Seguer., Myosotis sylvti Hoffm., Nemophil menziesii Hook & Wlker-Arnott, Oenother frutios L., Oenother missouriensis Sims, Oenother lmrki devries, Oenother speios Nuttll, Ppver rhoes L., Penstemon sp., Rtiid pinnt (Venten.) Brnh., Rtiid olumnris (Nuttll) Woot. & Stndl., Rudeki hirt L., Rudeki fulgid Ait. Goldsturm, Slvi frine Benthm, Seneio smllii L., Solidgo sp. L. (lol), Solidgo sp. L. (dwrf), Veren rigid K. Spreng., Vii stiv L., Viol ornut L, Viol spp. Signifine to the Nursery Industry Inresing use of perennil plnts in lndsping nd rodside plnting will preditly led to emergene of new pest prolems. The hrysomelid eetle Phedon desotonis, lthough previously onsidered rre, is undnt on preferred plnts tht re ommon omponents of wildflower mixes nd single speies perennil plnt prodution in the nursery. Knowledge of the eetle s life history nd plnt preferenes will permit protive mngement of this emerging pest. Introdution Reeived for pulition My 6, ; in revised form June 6,. Txonomi determintions nd ssistne y Ceil Smith nd Ed Riley re grtefully knowledged. Plnt txonomi determintions were mde y W. Corley. A. Wheeler improved the mnusript with his omments on n erlier drft. Professor, Reserh Coordintor nd Reserh Coordintor (retired), respetively. Phedon desotonis Blsugh is lef eetle (Coleopter: Chrysomelide) tht until reently hs een onsidered somewht rre (6,, ). It ws desried from single mle in Alm () tht previously hd een misidentified s P. purpure Linell (). An inresed use of ommeril wildflower mixes for rodside eutifition nd to enhne lndspe diversity hs lso provided potentil pest mngement enefits (4). Reent oservtions of dmge y P. desotonis to ornmentl Coreopsis spp. (e.g., 3) prompted n investigtion of its sesonl ourrene nd the plnt suseptiility mong speies of interest in wildflower plntings nd hereous plnt prodution. Methods nd Mterils Sesonl ourrene of Phedon desotonis in lndspe wildflower plntings. The ourrene nd undne of lrvl nd dult lef eetles were monitored t two lotions, Splding nd Pike Counties, GA. During 99, in Pike County, Smith Mix ustomized wildflower mix reommended y University of Georgi Hortiulture Extension speilists for optimum southestern urn olor (5) ws plnted in plots ( m (9 9 ft)). Wildflowers loomed ontinuously from spring to fll. Speies ontined in the mix were Ahille millefolium L., Centure ynus L., Cssi fsiult Mihux, Conslid migu (L.) P.W. Bll & Heywood, Coreopsis lneolt L., Coreopsis tintori Nuttll, Eshsholzi liforni Chmisso, Gillrdi ristt Pursh, Gillrdi pulhell Fougeroux de Bondroy, Monrd itriodor Cervntes ex Lgsk y Seguer., Nemophil menziesii Hook & Wlker-Arnott, Oenother speios Nuttll, Ppver rhoes L., Rudeki hirt L., nd Slvi frine Benthm. Wildflowers were seeded in Novemer 99 nd mulhed with whet strw. Borders etween plots were mintined vegettion free with spot pplitions of 4% glyphoste pplied t 4.7 liters/h ( qt/a). No dditionl heriides, insetiides, or fungiides were pplied. Plots were fertilized with mmonium nitrte t 37 kg/h (33 l/a) in August 99 nd 993. Wildflower plots were reseeded in 993. Plots ontining similr wildflower mix were mintined on the Griffin Cmpus in Splding County. J. Environ. Hort. (4): 3. Deemer

3 Previous oservtion (3) suggested tht the eetle hd single genertion with dults overwintering in litter nd lrvl dmge to wildflower plntings eoming pprent s erly s Mrh 5 th. Adults were present in lrge numers during My ut esed feeding y lte My 996. Vuum smples using Vortis vuum smpler (Burkrd Mnufturing Co., Ltd., Herferdshire, Englnd) were olleted in 998 t oth the Splding nd Pike County lotions during Mrh, April, My, nd June to etter define tivity of the eetle in the entrl Georgi re. Smples onsisted of ten sutions [. m (. ft )] of se durtion in eh of four loks. The smpler, whih resemles n inverted lef lower, ollets ground-dwelling insets in entrl hmer nd entrifuges the ontents, whih re then olleted in plsti up tthed to one side of the smpling mhine. Su smples of lrve nd/or dults per olletion dte were held t 4C (75F) on C. lneolt for possile prsitoid emergene. Host plnt ssessment. Initil evlutions for potentil plnt ssoitions ssessed 38 plnt tx in petri dish feeding studies for suseptiility to P. desotonis. Beuse severl other North Amerin Phedon spp. re ssoited with Brssiee (= Cruifere), ornmentls in this fmily nd two lines of nol were inluded s potentil s in this initil sreening. Exised plnt mteril ws pled on moistened filter pper in 5 m (5.9 in) dim petri dishes. Five dult nd five lrvl Phedon desotonis were introdued to eh dish. Ten replitions of eh plnt txon were evluted. Feeding fter 4 hr t 4C (75F) ws noted. Tx identified s sustining t lest some injury were then inluded in lortory preferene trils to determine plnt preferene nd reltive degree of dmge sustined y eh speies. Leflets of eh speies were rndomly ssigned to eh qudrnt of 5 m (5.9 in) dim petri dishes. Three dult or three lte stge (third instr) lrve of P. desotonis were onfined to eh petri dish. Lotion ws noted fter four hours nd gin t 4 hr. Dmge fter 4 hr exposure t 4C (75F) ws lso noted using rting sle where represented no dmge nd indited tht the plnt ws ompletely onsumed. Thirty replites were evluted. Dt were sujeted to nlysis of vrine nd mens were seprted using Fisher s proteted lest signifint differene test. Results nd Disussion Sesonl ourrene of Phedon desotonis in lndspe wildflower plntings. Lrve, dults, or oth stges of P. desotonis were olleted in vrying densities from Mrh 5 through June during 998 (Fig. ). By Mrh 5 (Julin dte 84), lrge numers of lrve were present t oth lotions. Site ws n urn sitution, while Site, in Pike Co., GA, ws in rurl setting. Development of popultions t Site lgged somewht ehind tht oserved in the residentil setting. The lrge numers of individuls olleted indite the high potentil for dmge y this speies. Lrve were most numerous t Site on Mrh 5 nd t Site on April (Julin dte 9). Adults t Site were most numerous on My (Julin dte ) nd on My 8 (Julin dte 8) t Site. Low numers of first nd seond instr lrve were gin olleted on My 8 (Julin dte 38), with dditionl lrve olleted on My 6 (Julin dte 46) nd June (Julin dte 5) suggesting synhronous popultion development or smll seond genertion. No further dults J. Environ. Hort. (4): 3. Deemer Men numer per smple Fig Adults Lrve Julin Dte Julin Dte Site Site 8 4 Sesonl ourrene nd undne of lrvl nd dult Phedon desotonis, lef eetle ttking Coreopsis spp. in wildflowers t Splding County (Site ) nd Pike County (Site ), GA, during 998. Men ± SEM numer per vuum smple. were olleted from the smple res fter June. Unidentified thinid prsitoids were rered from dults tht were olleted on My t Site nd My 8 t Site. At site, 5% of the eetles were prsitized. At Site, flies emerged from 45% of the eetles olleted. Host plnt ssessment. Among the 36 ornmentl nd two nol tx, only four speies, Coreopsis lneolt, C. vertiillt (L.), C. tintori, nd Bidens ristos (L.), ll memers of the Asteree = Composite, were suseptile to onsistent feeding y lrvl or dult eetles (Tle ). An dditionl 5 memers of the Composite were not fed upon in these no-hoie feeding tests. No plnts from the dditionl plnt fmilies evluted were fed upon y P. desotonis in petri dish ssys. Coreopsis lneolt ws preferred y lrvl P. desotonis in oth the 4 (F 4,45 = 3.8; P =.) nd 4 hr (F 4,45 = 5.9; P =.) evlutions s mesured y lotion of lrve (Fig. ). Adults were eqully distriuted mong plnts or etween plnts t the 4 hr (F 4,45 =.5; P =.) ssessment, ut were most ommonly found settled on the Bidens ristos t the 4 hr (F 4,45 = 7.3; P =.) evlution (Fig. ). Although dults were most numerous on Bidens fter 4 hr, the most severe dmge y dults ws oserved on C. tintori nd C. vertiillt (F 3,6 = 7.; P =.) (Fig. 3). Lrve most severely dmged C. lneolt nd C. vertiillt in these petri dish ssys (F 3,6 = 3.3; P =.).

4 Tle. Aeptility of vrious plnt tx s potentil s for Phedon desotonis sed on petri dish ssys. Fmily Txon Host eptility z Borginee Myosotis sylvti Hoffm. Cryophyllee Dinthus deltoides L. Cerstinum iererstenii DC. Asteree (= Composite) Ahille millefolium L. Aster levis L. Per. Bidens ristos L. Centure ynus L. Chrysnthemum leunthemum L. Coreopsis lneolt L. Coreopsis tintori Nutt. Coreopsis vertillt (L.) Ehine purpure (L.) Moenh. Euptorium olestinum L. Gillrdi ristt Pursh. Per. Gillrdi pulhell Foug. Rtiid pinnt (Venten.) Brnh. Rtiid olumnris (nutt.) Woot. & Stndl. Rudeki fulgid Ait. Goldsturm Rudeki hirt L. Seneio smllii L. Solidgo sp. L. (lol) Solidgo sp. L. (dwrf) Brssiee (= Cruifere) Brssi npis Iris Brssi npis Flon Loulri mritim (L.) Desv. Lmiee (= Lite) Monrd itridori Cerv. Slvi frine Benth Fee (= Leguminose) Vii stiv L. Trifolium inrntum L. Ongree Oenother frutios L. Oenother missouriensis Sims Oenother lmrki devries Oenother speios Nutt. Rnunulee Aquilegi erule Jmes Srophulriee Penstemon sp. Verenee Veren rigid K. Spreng. Violee Viol ornut L. Viol spp. z Criteri for designting plnt s inluded onsistent oservtions of feeding in no hoie evlutions in petri dish trils onfirmed y feeding oservtions in the lndspe or field plots Men numer per plnt Adults 4h off plnt Bidens sp. C. lneolt C. tintori C. vertiillt Lrve 4h Adults 4h Lrve 4h Men dmge rting Bidens sp. C. lneolt C. tintori C. vertiillt Adults Lrve Fig.. Distriution of dults nd lrve of Phedon desotonis in preferene test mong four plnt speies t 4 hr nd 4 hr fter introdution of the eetles. Men ± SEM numer of dults or lrve loted on plnts in petri dish feeding ssy. Fig. 3. Dmge used y dults nd lrve of Phedon desotonis in preferene test mong four plnt speies 4 hr fter introdution of the eetles. Men ± SEM dmge using rting sle where represented no dmge nd indited tht plnt mteril ws ompletely onsumed. J. Environ. Hort. (4): 3. Deemer

5 Our field oservtions lso support the onlusion tht fine leved Coreopsis spp. sustin intense dmge y P. desotonis oth in mixed speies wildflower stnds, hereous plnt eds nd on ontinerized perennil nursery plnts (S.K.B. personl oservtion). Coreopsis lneolt is lso highly preferred. Wheeler nd Hoeeke (6) reently noted tht this purportedly rre eetle hs een olleted in Alm, Georgi, South Crolin, nd Tennessee on Coreopsis grndiflor Hogg ex Sweet in rok-outrop ommunities nd on ornmentl Coreopsis. Wildflower mixes ontining Coreopsis spp. hve eome inresingly widely plnted throughout the southestern United Sttes. A similr inrese in prodution nd purhse of perennil plnts, inluding Coreopsis spp., during the 99s, might provide dditionl plnts for the eetle s popultion inrese or hitt expnsion. Phedon desotonis sustntilly redued Coreopsis density in wildflower plots in Pike Co., GA. Adults nd lrve re signifint mortlity ftors for seedlings nd lso prevent flowering nd seed set y lrger plnts. Between 993 nd 995, density of Coreopsis in the perennil plnt omposition deresed y out 75% in our field plots. We hve lso oserved P. desotonis on potted nursery stok of C. rose Nutt. Although the eetle is esily ontrolled y insetiides, their pplition to wildflower res runs ounter to the generlly low input intent of suh plntings. Literture Cited. Blsugh, E.U., Jr A txonomi revision of the genus Phedon north of Mexio (Coleopter: Chrysomelide). North Dkot Insets Shefer-Post Series 5, 73 pp.. Blsugh, E.U., Jr. nd K. L. Hys. 97. The lef eetles of Alm (Coleopter: Chrysomelide). Auurn University Agriulturl Experiment Sttion Bulletin 44: Brmn, S.K. nd W. Corley Lef eetle dmge to Coreopsis in low mintenne wildflower plntings. Pro. Southern Nurserymen s Assoition Reserh Conferene 4: Brmn, S.K, A.F. Pendley nd W. Corley.. Influene of ommerilly ville wildflower mixes on enefiil rthropod undne nd predtion in turfgrss. Environ. Entomol. 3: Corley, W. 99. Wildflower estlishment nd ulture for medows, euty spots nd rodsides. University of Georgi, Ornmentl Hortiulture Ft Sheet H. 6. Wheeler, A.G. nd E.R. Hoeeke.. Phedon desotonis Blsugh (Coleopter: Chrysomelide): New distriution reords, first -plnt ssoitions, nd sesonlity of seldom-olleted eetle of rok-outrop ommunities. Pro. Entomol. So. Wsh. 3: J. Environ. Hort. (4): 3. Deemer 3