Screening Sunflower Varieties for Reaction to Infestation by Sunflower Midge & Insecticide Update

Transcription

1 Screening Sunflower Vrieties for Rection to Infesttion by Sunflower Midge & Insecticide Updte Jnet J. Knodel 1, Ptrick B. Beuzy 1, Jrrd Prsifk 2 nd Theres A. Gross 2 1 Deprtment of Entomology, North Dkot Stte University, Dept. 7650, P.O. Box 6050, Frgo, ND Northern Crop Science Lbortory, USDA, ARS, 1605 Albrecht Blvd. N, Frgo, ND Host Plnt Resistnce Screening Sunflower (Helinthus nnuus L.) is ntive to North Americ, nd severl insect pests ttck sunflower cusing economic losses to production in the Gret Plins. Sunflower midge, Contrini schulzi Ggné (Dipter: Cecidomyiide) is one of the mjor insect pests infesting the heds of sunflower (Chrlet et l. 1997, Knodel et l. 2007). Eggs re lid on the developing buds, either in the center of the bud or beneth the brcts. Lrve feed on tissue beneth the brcts nd in the developing receptcle (Knodel et l. 2007). Dmge from light infesttions is evident by brct scrring only, nd little or no economic loss occurs. With more severe infesttions, hed cupping nd centrl ded res occur reducing hed size nd loss of seed development (Chrlet et l. 1997). Dmge is typiclly restricted to field mrgins in lightly infested fields, lthough field-wide dmge nd significnt yield loss cn occur in hevily infested fields. In recent yers, midge ctivity hs been limited to few hot-spots in North Dkot, such s the Crrington re. The best pest mngement option for growers experiencing or nticipting dmge from sunflower midge is to not grow sunflower. In this study, sunflower hybrids were evluted for sunflower midge resistnce. s exhibiting bove verge resistnce could be used s n lterntive pest mngement strtegy for mitigting dmge cused by sunflower midge. However, the performnce of such lines my not be dequte in res with high sunflower midge pressure. Mterils nd Methods Fifty-seven sunflower hybrids including 17 confections nd 40 oilseeds were evluted for sunflower midge resistnce in Seed compnies were sked to submit hybrids to be tested specificlly for susceptibility to sunflower midge infesttion. Single row, replicted trils were estblished t the NDSU Sunflower Midge Nursery ner Mpleton, ND. Sunflower hs been plnted t this site for over 20 yers nd sunflower midge hs lwys been present, lthough t times the infesttion level hs been low. Two plnting dtes (25 My nd 8 June) were used to ensure sunflower midge infesttion. Sunflower hybrids were plnted in 22-ft. single row plots with 4 replictes. Five plnts within row (excluding the outermost plnts t both ends of the row) were ssessed for sunflower midge rection ( totl of 20 heds per hybrid). 894 ws plnted t set intervls within ech test to llow stndrd mesure of midge injury. Sunflower midge dmge rtings were tken on 1 September using the necrosis index nd the Brcken scle (Brcken 1991). Necrosis index mesures the extent of necrosis t the bse of the brcts cused by sunflower midge lrvl feeding nd the rnge is 0 (no injury) to 5 (50% or more of ech qudrnt of the hed with midge necrosis). Brcken scle mesures sunflower midge injury symptoms on the

2 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge 2 following scle: 0 (no injury), 1 (brct dmge evident), 2 (light cupping, receptcle thickening), 3 (moderte cupping, receptcle thickening ½ hed dimeter), 4 (extreme cupping, receptcle thickening >½ hed dimeter) nd 5 (hed closed, no seeds present) (Brcken 1991). Results nd Discussion Due to the wet spring, the lte plnting dte (8 June) ws lost. Dmge rtings for the sunflower midge hybrid evlution tril from the first plnting dte on 25 My re presented in Tble 1. The tril men ws 1.6 for the Brcken scle cross ll hybrids. Fifty-nine percent of the confection hybrids nd 40 percent of the oilseed hybrids hd Brcken score of less thn the tril men. The rnge for Brcken scle ws from 0.6 to 3.0 for confection hybrids nd 0.6 to 2.5 for oilseed hybrids. For necrosis, the tril men ws 2.1 cross ll hybrids. Fifty-three percent of the confection sunflowers nd 60 percent of the oilseed sunflowers hd necrosis rting less thn the tril men. The rnge for necrosis ws from 0.4 to 3.4 for confection hybrids nd 0.4 to 3.8 for oilseed hybrids. Since the erly plnting dte ws lter thn norml, this my hve mitigted sunflower midge dmge in Results were published in the nnul North Dkot nd South Dkot Sunflower Performnce Testing Bulletin (NDSU Extension Service publiction A-652), North Dkot Field Crop Insect Mngement Guide (NDSU Extension Service publiction E-1143), nd were mde vilble on the NDSU Extension Publiction website. Previous reserch documented the resistnce or tolernce of vrious sunflower hybrids to sunflower midge infesttion (Brewer 1998, 1999, 2000, 2002, Brewer et l. 1994, Chrlet nd Knodel 2008, 2009, Knodel et l. 2010, 2011). Tble Sunflower Midge Evlution Tril - Mpleton, ND Sunflower Midge Necrosis Score (0-5) Dmge Score Rting Brcken Scle (0-5) CHS 11-M Low 0.75 CHS 11-M Low 0.60 CHS 11-M Low 0.85 CHS 11-M Low 1.00 CHS 11-M Moderte 1.65 CHS 11-M Low 0.90 CHS 11-M Low 0.80 CHS 11-M Low 0.90 CHS 11-M Low 1.00 CHS 11-M Moderte 1.42 Mycogen 8N270CLDM 1.90 Low 0.95 Mycogen E Low 0.75 Mycogen E Low 0.55 Mycogen E Moderte 1.15 Mycogen E Low 0.85

3 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge 3 Tble Sunflower Midge Evlution Tril - Mpleton, ND Sunflower Midge Necrosis Score (0-5) Dmge Score Rting Brcken Scle (0-5) Mycogen E Low 1.00 Mycogen E81423DM 0.60 Low 0.45 Mycogen E81424DM 1.55 Low 1.00 Mycogen E Low 0.45 Mycogen E81552DM 1.45 Low 0.90 Nider LN Low 0.95 Nider MN Low 1.00 Nider MN Low 0.50 Nider ON Low 1.15 RRC Low 0.55 RRC Low 0.85 RRC 2215CL 1.05 Low 0.55 Seeds 2000 Bdger DMR 0.55 Low 0.40 Seeds 2000 Cmro 0.85 Low 0.45 Seeds 2000 Jgur 1.60 Low 1.05 Seeds 2000 Jgur DMR 2.85 Moderte 1.30 Seeds 2000 Torino 0.65 Low 0.40 Seeds 2000 X Moderte 1.50 Seeds 2000 X Moderte 0.85 Seeds 2000 X Low 0.80 Seeds 2000 X Low 0.75 Seeds 2000 X Low 0.75 Seeds 2000 X Low 0.80 Syngent 3158 NS/CL/DM 1.30 Low 0.60 Syngent 3495 NS/CL/DM 1.25 Low 0.60 Syngent 3733 NS/DM 1.00 Low 0.65 Syngent 3845 HO 1.95 Low 0.85 Syngent 3990 NS/CL/DM 1.05 Low 0.60 Syngent 3995 NS/SU 1.10 Low 0.70 Syngent 4596 HO/DM 1.75 Low 0.85 Syngent 4651 NS/DM 1.20 Low 0.70 Syngent NX Moderte 1.55 Syngent NX Low 1.00 USDA 412HO/ Low 0.65 USDA 412HO/ Moderte 1.00 USDA 412HO/ Low 0.90 USDA 412HO/ Low 0.60 USDA 445/ Low 0.80 USDA 445/ Moderte 1.10

4 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge 4 Tble Sunflower Midge Evlution Tril - Mpleton, ND Sunflower Midge Brcken Necrosis Score (0-5) Scle Dmge (0-5) Score Rting USDA 445/ Moderte 1.75 USDA 445/ Moderte 0.95 USDA 894 Check 1.90 Low 0.75 Men LSD Sunflower midge necrosis score mesures the extent of necrosis t the bse of the brcts cused by sunflower midge lrvl feeding. The rnge is from 0 (no injury) to 5 (50% or more of ech qudrnt of the hed with midge necrosis). Dmge rting is bsed on the necrosis score, with score vlues of = low, = moderte, nd 4-5 = high. Brcken scle mesures sunflower midge injury symptoms on 0 (no injury) to 5 (hed closed, no seeds present) scle. Preliminry Study: Synthetic Auxin 2,4-D Testing for Screening Sunflower s for Tolernce to Sunflower Midge Methods nd Mterils The first repliction of the 2011 sunflower midge hybrid evlution tril ws evluted using 2,4-D injection technique tht ws developed by Brewer et l. (1994). Techniques described in Brewer t l. (1994) were used to inject five heds of ech hybrid. A stock solution of 10 mm 2,4-D in wter ws prepred using nlyticl grde 2,4-D. Buds of cm in dimeter were selected, nd then the 2,4-D solution ws injected into the buds t right ngles using hypodermic needle (16 guge). The needle ws inserted to 0.5 cm, withdrwn slightly to crete smll reservoir, nd then the test solution injected. A totl of 0.5 ml test solution ws distributed eqully mong three injection sites bout 120 degree prt on ech bud ( ml per injection site). Injections occurred on three different dtes (25 July, 3 August nd 8 August) to ccommodte for differences in bud sizes mong hybrids. Results nd Discussion The 2,4-D injected buds hd significntly (2x) higher brcken dmge scle (2.2) compred to the non-injected buds (1.0) (LSD = 0.882, P < 0.05). In Figure 1, the Brcken scle for non-injected buds did not pper to correlte with injected buds mong the different hybrids. These differences my hve been due to ctul hybrid differences in response to 2,4-D nd/or low midge pressures in the tril mking vlid comprisons difficult. This technique needs further reserch to stndrdize it for use by seed compnies.

5 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge Figure 1. Comprison of 2,4-D injected versus non-injected Buds for Screening Sunflowers for Tolernce to Sunflower Midge Blue horizontl line is tril men of injected buds (2.2) Red horizontl line is tril men of the non-injected buds (1.0) Injected Non-injected Brcken Scle Sunflower Insecticide Efficcy Testing The efficcy of HGW86 (Cyzypyr ) nd Prevthon (RynXypyr ) in the Group 28 Chlorntrniliprole ws evulted for control of bnded sunflower moth (Cochylis hospes Wlsinghm) nd red sunflower seed weevil (Smicronyx fulvus LeConte) in sunflower t coopertor field ner Mpleton, ND. Group 28 chemistry cts s gonists of the rynodine receptors of insect pests. The ctivtion stimultes the relese of clcium ions from the internl stores in smooth nd strited muscle cells, cusing impirment of muscle regultion resulting in lethrgy, cesstion of feeding, reduction of reproductive success nd, ultimtely, insect mortlity (Dupont Cyzypyr Technicl Dt Sheet). Mterils nd Methods Prior to plnting, Prowl herbicide t 3 pints per cre nd dry ure t 80 lbs per cre were pplied nd incorported. The oilseed sunflower hybrid NK2930NS/DM ws plnted on 5 June. Below ground cutworm feeding (primrily dingy cutworm) ws observed in the tril shortly fter emergence. Mustng Mx t 4 fl oz per cre ws pplied t this time to prevent further cutworm injury to the tril. The tril ws rrnged in rndomized complete block design with four replictions. Plots were 30 feet long by 10 feet wide nd contined 4 rows t 30-inch row spcing, with plnt popultion of pproximtely 18,000 plnts per cre. Ten-foot lleys surrounded ech plot to llow for sprying nd to encourge coloniztion of trget insects.

6 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge 6 Insecticide tretments included: 1) Untreted check, 2) Asn XL t 9.6 fl oz/cre (s stndrd), 3) HGW86 t 3.4 fl oz/cre + MSO t 0.5% v/v, 4) HGW86 t 6.75 fl oz/cre + MSO t 0.5% v/v, 5) HGW86 t 10.1 fl oz/cre + MSO t 0.5% v/v, 6) HGW86 t 13.5 fl oz/cre + MSO t 0.5% v/v, 7) HGW86 t 3.4 fl oz/cre, 8) Prevthon SC t 9.8 fl oz/cre, nd 9) Prevthon SC t 13.3 fl oz/cre. Folir tretments were pplied on 5 August when the mjority of plnts reched the R5.1 growth stge. Tretments were pplied with trctor-mounted CO 2 spryer using TeeJeet XR80015 nozzles t 40 psi nd spry volume of 15 GPA. At mturity, 10 heds per plot were rndomly selected nd hrvested. Heds were plced in dryer for 2 dys t 95 F to ensure complete drying. Individul heds were mnully threshed nd clened. A rndom 200 seed subsmple ws tken from ech hed, nd the number of BSM nd RSW-dmged seeds were counted nd recorded for ech subsmple. BSM nd RSW percent dmge for ech hed ws then clculted. Anlysis of vrince (ANOVA) ws conducted on percent BSM dmge nd percent RSW dmge using PROC GLM in SAS sttisticl softwre (SAS Institute 2008). Tretment mens were compred using Fisher s LSD t p Results nd Discussion In Figure 2, the percent dmged seed by bnded sunflower moth nd red sunflower seed weevil is presented. All tretments hd significntly less bnded sunflower moth dmge thn the untreted check. The top three insecticide tretments with the lowest percent dmged seed for bnded sunflower moth were in descending order: Prevnthon SC t 9.8 fl oz/cre, HGW86 t 10.1 fl oz/cre + MSO t 0.5% v/v, nd Asn XL t 9.6 fl oz/cre. These three tretments hd significntly lower percent dmged seed thn HGW86 t 3.4 fl oz/cre (no MSO) nd the untreted check. Red sunflower seed weevil popultions were too low to determine product efficcy, nd there were no significnt differences for dmged weevil seeds mong tretments. HGW86 (Cyzypyr ) nd Prevthon SC (RynXypyr ) in Group 28 Chlorntrniliprole re currently not registered in sunflower. These dt suggest tht higher rtes of HGW86 (Cyzypyr ) nd both rtes of Prevthon SC (RynXypyr ) would be efficcious insecticides for control of sunflower insect pests. Figure 2. Tretment Mens for Percent Dmged Seed for Bnded Sunflower Moth (BSM) nd Red Sunflower Seed Weevil (RSSW) t Mpleton, BSM RSW % Dmged Seed b bc bcd bcd bcd cd cd d Fisher's LSD; P< 0.05

7 2012 NSA Proceedings Sunflower Midge & Insecticide Updte Pge 7 Literture Cited Brcken, G.K A dmge index for estimting yield loss in sunflowers cused by sunflower midge. Cn. J. Plnt Sci. 71: Brewer, G. J Sunflower hybrids - sunflower midge score. In D. Berglund, North Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Brewer, G.J Sunflower hybrids - sunflower midge score. In D. Berglund, North Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Brewer, G.J Sunflower hybrids - sunflower midge score. In D. Berglund, North Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Brewer, G.J Prospects for mnging sunflower midge. Proc. 24 th Sunflower Reserch Forum, 9 pp. Ntionl Sunflower Assocition. Jnury 17-18, URL: Brewer, G.J., M.D. Anderson nd N.V.R. Urs Screening sunflower for tolernce to sunflower midge using the synthetic uxin 2,4-dichlorophenoxycetic cid. J. Econ. Entomol. 87: Chrlet, L.D., G.J. Brewer, nd B. Frnzmnn Insect pests, pp In Sunflower Technology nd Production, A.A. Schneiter (ed.), Agron. Ser. 35. Am. Soc. Agron., Mdison, WI. Chrlet, L.D. nd J.J. Knodel Sunflower midge hybrid tril, In H. Kndel nd K. Grdy, North Dkot nd South Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Chrlet, L.D. nd J.J. Knodel Sunflower midge hybrid tril, In H. Kndel nd K. Grdy, North Dkot nd South Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Knodel, J.J., nd L.D. Chrlet IV. Pest Mngement Insects. In Sunflower Production, D.R. Berglund (editor), NDSU Ext. Serv. A-1331 (EB-25 Revised). Knodel, J.J., L.D. Chrlet nd P.B. Beuzy sunflower midge hybrid evlution tril Mpleton, ND. In H. Kndel nd K. Grdy, North Dkot nd South Dkot hybrid sunflower performnce testing North Dkot Extension Service A-652 (revised). Knodel, J.J., J. Prsifk, P.B. Beuzy nd T. Gross sunflower hybrid midge evlution Mpleton, ND. In H. Kndel nd K.A. Grdy, North Dkot nd South Dkot hybrid sunflower performnce testing North Dkot Extension Service A- 652 (revised). SAS Institute SAS system for windows relese 9.2. SAS Institute, Cry, N.C. Acknowledgments The uthors thnk M. Andrews, III for use of his lnd nd coopertion with this study. This reserch ws supported by the Ntionl Sunflower Assocition Grnt Progrm. We lso cknowledge Syngent Crop Protection for providing NK2930NS/DM seed for the insecticide efficcy tril, nd severl seed compnies for providing seeds for hybrid vriety testing for host plnt resistnce tril.