DAMAGE TO SOYBEAN SEEDS BY SOUTH ANERICAN STINK BUGS1 ' 2

G.P. WALDBAUER 3

ABS TRACT

Tests with caged soybean plants in the field near Palmira, Co lombia, showed that two stink bugs which are common there in soybean fields, perditor (F.) and Acrosternum n,arqlnatum (Beauv.), dama ge soybean seeds by piercing the pode. The daniage, consisting of punctu res, wrinkling and staining of the seed coat and discoloration of the cotyledons, matches published descriptions of darnage to soybeans by North American and Brazilian stink bugs.

INTRODUCTION

Stink bugs cause serious losses of soybean yield and quality in North America by piercing the pods and feeding froni the developing seeds. Several stink bugs occur on soybeans in South Anierica, but lit tle is known about their effect on this crop. This paper shows that two of the more common stink bugs of soybean fields near Palmira, Vaile, in the Cauca Valley of Colonibia cause significant damnage to soybean seeds. Stink bugs known to damage developing soybean seeds in North Arnerica are: Acrosternum hZare (Say) and Eunch-itw servus (Say) (Dau gherty et ai., 1964); E. euschiicZe (Vol ienhoven), E. tristig7nu8 (Say), F variolarus (Beauv.), and Tiyo taor (F.), (Daugherty, 1967); Nesara viridula (L.) (Miner, 1966; Todd and Turnipseed, 1974). From February to July of 1971 1 collected the foliowing numbers of stink bugs frota soybean fields near Palmira: Piezodorus quilditi (Westw), 207; Thyanta perditor (F.), 78; Puschistua crenator (F.), 50; Acrosternum marginaturri (Beauv.), 40; Morrnidea sp. 1, 24; Posidurr ris pinuo (Dall.), 23; Edessa nedítabunda (F.), 19; Thyanta antiguennio (Westw.), 4; Osbalus pugnax torridus (Sailer), 3; O. ornatus (Sailer), 2; and Euschintus atroz (Westw.), 1. The cosmopolitan [azara viriduL.a daniages soybean seeds in Argen tina and Brasil (Rizzo, 1972: Link & Costa, 1974; Link et al., 1971 &

Recebido eis 31/05/77. ': . 2 Supported by the International Soybean Resource Base (INTSOY), Office of International Agricultural Programs, Coliege of Agriculture, Univer city of Illinois; and the Illinois Natural History Survey. mDepartment of Entomology and the Illinois Agricultural Experiment Sta tion, University of Illinois, and the Illinois Natural History Survey Urbana, Illinois 61801. WALDBAUER ANAIS DA S.E.P., 6(2):224-229, 1977

1973). En Brasil ['1 rodorua (i1d1ni? attacks soybean pods, and i'deesa rndi iabanh ar tacke the s tems hu t not the pods (Panizzi, 1975; Panjzzj & Smith, 1977). O. ruunax, the Rice stink bug, occurs on grassy weeds ia soybean fields and does amor injury to soybean seeds (Niner, 1966). The effect of the otlier species which were taken on soybeans in Colom bia has not heen previoiisly reported.

MATERIALS AND METI-IQDS

On JLIOC 28, 1971 1 enclosed 8 soybean plants of an experimental ploL of 'I.C.A. Liii' in individual cages, gauze cylinders supported by wire frames fastened to stakes. Some leaves touched the gauze, hut the pods were inaccessible to outside of the cages. The plants were searched for egg masses and sprayed with 0.27, DDVP, an insecticide with a short residual life. On July 2, six of the cages were ínfested with fietd-collected stink bugs, one group of 3 cages with T/uianl,a períii/or and another nearby group of 3 with Arrna /'auni marqivatum. Ezicii group inciuded a fourth,uninfested control cage. The numbers and etages 01 the bugs placed in eaï cage are shown in Table 1. The plants then had soft green seeds wbich were nearly fulI-sized (stage R5-R6 according to Fehr eL al.,1971). On July 12 the surviving insects were reinoved from the cages and counted, and the plants sprayed with SevirO to prevent further injury. On July 26 the seeds were harvested by hand, counted, weighed, and exarnined for damage.

AND DISCUSSION ri RESULTS

1 had already seen T. peidí1.or and A. rnargine,urn attack soybean pods in the field near Palmira, and had reared them on soybean pods in the laboratory. The fieid cage experimcnts (Table 1) confirm these oh servations, leaving no doubt that these species damage soybean aeeds. Plants caged wiLli 12 stink bugs of either species had over 807, claniaged seeds, and at ieast 73% of these seeds bore recognizabie feeding pune Luras. This is well above the injury levei found in either uninfested control cage: 14% or 24% damaged seeds with only 2.47 or 3.5% of them showing recognizabl.e feeding puncturcs (Table 1) . Some damage was to be expected co the control plants because they vera accessible to stink bugs before they were caged. In the cages with 6 or 3 stink bugs there was not a doar corre spondence between infestation levei and the percent of dainaged and pune tured seeds. This was because mortality tended to eqtla!ize the infesta tion leveis in these cages, and because 00 OflO piant there was feeding by a few nymphs from an egg mass which was missed when the plant WOS ia ged. Nevt'rtheless, plants with lesser infestations had damage leveis wel 1 above those in the control cages, bu t below those in the cages with 12 bugs each; from 40% to 63% of their seeds had been daniaged, and from 23% to 37% ol these seeds bore visible feeding punctures (Table 1).

-22 5- TABLE 1 - Damage to soybean seed by various nunbers of Tb:r rdiror or 2r :'- ca ged on single soybean plants in the field near Pahira, Valie, Colombia. A total of 8 plants is included in the experinent. The insects were on the plants for 10 days, starting rj when the plants were R5-R6.

No. stink bugs: Seeds:

Placed Surviving Total With purple Damaged a Punctured Undeveloped in at erto of on seed-statn -x wt. -x wt. (7) cage experiment ptant («) uninjured injureda

T. perdi ror 12 11 173 83.8 76.3 12.1 6.4 0.14 0.11 -i 6 1 150 63.3 35.3 8.7 4.0 0.12 0.10 3 2 139 48.9 37.4 4.3 0.7 0.12 0.10 0 u 248 24.2 2.4 15.7 6.0 0.14 0.06

12 10 98 80.6 73.5 O 3.1 0.14 0.13 3 176 39.8 23.3 1.1 2.8 0.13 0.09 138 47.9 31.9 10.9 0.7 0.12 0.09 ° O O 199 14.1 3.5 2.5 4.0 0.14 0.10

aIncludes aU punctured and undeveloned seeds bit not seds with purple seed-stain. blncludes 9 large nymphs. CIncludes 4 large nyrnphs. dlncludes 2 large nymphs. eIn addition there were a few small feeding nymphs from an egg mass missed when the plant was caged. - WALDBAUEP ANAIS DA 3./.B., 6(2):224-229, 1977

The dainae matchos pubi ished photographs and descr itiana of da mage te soybean aceds 1w otlier stink hug spec ice (Daiighertv, 1967; .len sen & Newsoin, 1972; Kilpatrick & llartwig, 1955; Mincr, 1966; iedd,1976; & Tumor, 1967). flarna;e vari ed from not}ii no more than ífcdi ng punctures te varying degrees ei wrinkling and disccloratien. Tio I)IInctIres are dark, circular spots usual ly located in a deproes 1 on, and often a000mpa nied hy a wrinkiing and etaining of the seed cont which varies in ex tent, but may revel - an ent 1 re seed. The cetviedon uinderl y i ip, the wrin kled arca is usual 1 y i-h;ulky wIui te and more or less sunku'n. Some seeds failed te develop. Thev werru uuhriveied, c]ry, and aheuii: 3 mm lo diarneter. The peru'entago ei uindeveluped seeds was 001 (errei ated with the levei of infestati ofl in my cages (Tahie 1), biut this dois not mean that this inury is not assoei ated with stink bug feed ing . 1 1 prohably occur red befero lhe plante were eaged . i)aiigherty cl ai. , 1964, fouind a signi f i rant correi at ian between the number of unduuveloped soocis and the le vel of stink bug iníestatien on caged soybean planta. IIOWEvor, , they ca ged and infi'stcd thei r planta aI a unueh earl er deveiopruuuuura 1 Stage, when the planta were stili hlussoming and had anly cmii hk ai the lo wer nodes . leed 1 np puunetures were vis i hi e on about 6' f my uundeve loped seeds, hut were pruhahiy ohscured on Lhe rernai nder by the extrema shri veling. Some of the seeds from my cxperiment were apparenlly iníested by the puirpie seed-stain fungus, ('er e7cnnl HAMA (ilat . & Tomoy) Kilpatrick and h-lartwig, 1955, found that stink bug injurv is not impor tant in the spread of this fungos, My f inchings agree; purplc secd-stain was not associated with levei of infestation in the cages (Tabie 1), and oniy a few of the stained sccds hora feecling punctures. Therc is no possiblity of punctures heing obscured because none of the s tained seeds were severeiy shriveled. Tabie 1 shows that damaged seeds were nmuueh 1 igh ter than undamna ged seeds. The mean wei ghts of ali seeds claruiaged by T. perF ur and A. lnarc/000t.um respectively were 27% and 22% less than the mean weights of undaniaged seeds irem the sarne piants. lo addition te the above experiment, 1 aaeessed the extent ol stink bug dainage te a eomnmmuerciai soybean planting at Pdlmira by exanui ning the mature seeds frommm 12 ptants picked ai rondam irem a field of 1 .C.A. Peiicano' whicli, whien the piants were 1'ru1, Iiad mie infestaLion of A orou teruws urhly(/ moo um meos noz ? o, í - u; a 7a /. y and TJynta periUtor. Twenty-eight percent of the 2178 seeds had heen injured. The uninjured seeds hzud a mean weight ei 0.186 g each, wimile the injured seods wcighed only 0.130 g each, a weight reduction of :30%. If the sarne levei cl' injury provai lcd throughout the ii eH, the yield had ben reduced 8.5% by weight. This propcirtionaI reiationship hetween the percentagc of damnaged seeds and the overail reduction in yield is remarkably similar to that ohlained by Miner, 1966. He found an overali yield reduction of 8.4% when comnparing stink bug infested piants with 33% darnaged seeds with control plants with 9% darnaged seeds.

-227- WI\LDBAUER A1MIS T)A [7.J:.R., 6(2):224-229, 1977

ACKNOWLEDO CM EN'I'S

1 thank rite Instituto Colombiano Agropecuario for allowing me Lo use Lhe íaeilities at their Centro N;ciona1 de Investigaciories Agro pecuaria in Palmira, and Lhe staff at Palmira, especially tu is Carnaclio, AI f redo Sal da ri aga, Rei na 1(10 Cardenas , ;uid Adolfo Trochen who he Iped i n many ways - 1tiect ideol íi cations were hy: L.H. Roiston, Dept . of Ento inology, Louisiana Srate Univ., Baton Rouge; R.C. Froeschner, Dept. of Entornology, NMNII, Sinitlisonian Tnstitution, Washington, D.C.; J. L. I-Ierring, Systernatir EnLomelogy laboratury, lnsect identification and Be neficial ínsect lntroiliictj.on Institute, A.R.S., It.S.D.A.; andC.L. Cod frey and .1.1<. Botiseinan of Lhe Internalional Reference Coliection oL Soy bean-associated Ar tli ropods, a joint project of Lhe Illinois Nato cal Ilis tory Survey and the Liniversity of Illinois.

REFERENCES CITEO

DAUCHERTY, D.M. Pentatomidae as ve&tors of yeast-spot disease of soybe aos. J. Foon. Kntm?a/. , 60:147-152, 1967. ; NEIJSTADT, M7iT.; GEH[1KE, C.W.; CAVANAIl, L.E.; WILLIAMS, L.F.; GREEN, D.F. Ao ev1uation aI damage to soybeans by brown and green stink hugs. J. Eaori. Entorno!.. * 57:710-722, 1964. FEHR, W.R.; CAVINESS, C.E.; BIJRMOOD, D.T.; PENNINGTON, J.S. Stage of development descriptions for soybeaos, Gl!fcina max (L.) Merrili. Crop Scr., 11:929-931, 1971. JENSEN, R.L. & NEWSOM, L.D. Effect of stink hug-damaged soybean seeds on germination, emergence and yield. J. Eac:n. Et0001. , 65:261-264, 1972. KILPATRICK, R.A. & FIARTWIG, E.E. Fungus infection of soybean seed as influenced hy stink bug injury. Pao/; Di cana Repor/ar, 39:177-180, 1955. LINK, D. & COSTA, E.C. Importncia da duraço do subperiodo floraço- -frutificaço, em soja, no dano causado por Ne.aara virddn7.a (L.). E. Centrü Ciee oas Rurais, 4: 243-246, 1974. ESI'EFANEL, V.; SANTOS, O. S. tios. Danos causados por perceve jos fit6fagos em graus de soja. E. Ccn.a Cincias Rurais, 1:9-13, 1971. MEZZONO, 1.C.; ABREIJ, L.E. V. Influncia do ataque de pentatomideos nas caracterTsticas agrono micas do gro da soja, (/!/o1r max (L . ) Mer. . AnaiíJoa. í. Isso! Brasil., 2:59-65, 1973. MINER, F.D. Diu1 y AM -entrai of stin?' 6opa ou soyLsaana. Arkaflsas Agric. Exper. Stat. Boi 1., 1966. 40 p. (Builetin, 708). PANIZZI, A.R. !d!ilipia a danos cau.nodos a soja por Pi,zo,-jIgrus iur1dr nil, icid?) (Rernip Lera: Panta/.omidae). Curi tiba, Univers ida de Federal do t'aran, Brasil, 1975. 129 p. (Tese-Mestrado). SMITH, J.G. Biology of Piaaodorus guil.diníi: develop ment time, adult sex ratio, and longevity. Ano. Entornol. Soa. Amer, 70:35-39, 1977. RIZ, H.F. Insectos y otros animales enemigos de la soja (Gtpcnirto irias'

-228- WALDBAUER ANAIS DA $.P.P., 6(2):224-229, 1977

(L.) Merril!) en la Argentina. R. ltoteo. Taf;ioovr.,8:64-49,1972. TODO, J.W. Effects of stink hitg feeding on soybean seed quality. In: DELL, L.D. ed., World Sbeon Raaorjrch, Proc, World Soybean Ilo searoli Confereia, 7075. Danvilie, lnters tato Printers and Pub lishers, 1976. p.611-618. (Seço 1 11). & TIJRNIPSEED, S.C. Effects of sotithern green stink bug da mago on yield and quality of soybeans. J. Econ. Enton,l., 67:421- -426, 1974. TURNER, J.W. The nature of damage hy Neaara oirldula (L.) to soybean seed. .oc-'na!ond J. Aqri... An('i. [OÍ. , 24: 105-107, 1967.

RESUMO

Testes de campo com plantas de soja mantidas em gaiolas, nas proximidades de Palmira, Colombia, demonstraram que duas espcies de percevejos (Hemiptera: Pentatomidae) -- T1nantc pordit.or (F.) e Acro6 trnwn marginatum (Beauv.), causam dano i soja atravs de picadura das vagens. Estas espcies so as mais comuns nos campos de soja daquela re giao. O dano consistindo de perfuraçoes, enrugamento da casca da semen te e descoloramento dos cotildones, corresponde a descriçes publica das sobre o dano causado por percevejos da soja no Nrasil e nos Estados Unidos.

-22 9-