Insecticides research coordination meeting for the period May 1986-May 1987

tT{ORLD TTEALTE ORGANIZATION ORGA}IIZATION MONDIALE DE I.A SAIITE ONCIIOCERCIASIS CONTROL PROGRAMUE IN U'EST AFRICA PROGMMMB DE LUTTE CONTRE LTONCHOCERCoSE EN AFRIQUE DE LTOUEST INSECTICIDE RESEARCTI COORDINATION MEETING FOR TITE PERIOD MAY 1986.MAY 1987 The annual lneectlctde reeearch coordlnatlon rneetlng was held ln Bouake fron 5 to 10 May 1987. Thle reporC contaLne only the eallenE facts; Ehe deCalle of the reeults obcalned are ln the annex. I \9861L987 caopalgna In the [,leetern zone, B. thurtn8lenslg H-14 was utlllzed excluetvely throughout the dry B€asooo The ot,her four avallable larvlcldee (cenephoa, chlorphoxtn, Peroethrtn and carboeulfan) were uaed durlng Ehe ralny B€8sooo Tenephos wae enployedln the areaa where resletance had never appeared ae well as ln areaa where lt had already been obeerved at the end of 1985. Thle ret,urn to a nornal eueceptlblllty canprobably be explalned by t,he coublned effect of the Eovement,a of blackfly populaElone and the uee of B.t. H-14. The ralnfall recorded durlng the ratny aeason was far below that of 1985 and markedly lese t,han the average. Nevertheleee, the 1986 relnvaslon waa anong thegreateet, ever recorded. The uee of the Ehree alt,ernattves of teoephoo durlng the hlgh-water perlod dld not poEe any particular probleu. Antl-relnvaslon experlmental larvlcldtng canpalgne are currencly belng carrted out both ln the t{eat (Gulnea) and ln the Eaet (Togo, Benln). The change of aerial epraylng conpany whlch took place aE Ehe beglnnlng of 1987 serlously affected aerlal operaElone ln January and February. In addltlon Eo an unavoidable adJuetment perlod, the Bost aerloue problens concern the epraylng equlpnenE. The presence of an external tank reduces by about 102 the fllght speed of the hellcopters; the lneectlclde releaee systen la conpllcated, not very rellable and up to Che preaent Elue doee not meet the Prograomerg needs. 2. ReeleEance eltuatlon The 1986/1987 eeaeon sas oarked by a very conelderable geographlcal extenelon of Che reslstance of the aavanna speclee to tenephos. In the lnttlal OCP area, new focl appeared on the Nlger (Banako reglon), the nlddle Saseandra (Cote drlvolre), the loser t{hlte Volta (Ghana) and rhe Orl (Togo, Ghana) (llap 1). -2- In the OCP area, teuephoe reelaEance ln the savanna epeclee probably evolvee accordlng to Eovement, and eeaeonal replaceuenta of the blackfly populstlonsl one cannot really talk of regreselon wlthln a populatlon. The larger Ehe area eprayed, the Eore llmlted the poealblllcy of replacenent of a reslstant populatlon by a sueceptlble populatlon w111 be and the greater the rtek of extenelon of the reslstance foct w111 be. Tenephos reslst,ance has appeared also ln Gulnea , ln the upper basln of the Nlger, on rlvers whlch have never been treaEed. Thls realotance whlch concerne S. elrbanum, S. experlmental dannosuu. S. soubrense senau lato and So aguanogun haa been conflrned by tenephoe Ereatmenta. It could be due to the nlgratlon durlng the harnattan per lod of S. elrbanum reeletant BEralns froo the Bauako reglon. In thac case, lc would be a conflrnaElon of the hypotheele already puE forward of a hybrldlzaElon wlth transfer of the reeletance gene(e). Unfortunately, the variety of the epeclea concerned ae seIl ae Ehe dlverelry and extent of Ehelr habltat do not nake lt poeelble Eo envlaage clean-ou! operatlons. Thle reslsEance greaEly compromlses the lnplenentatlon of an exteneion towarde Ehe rrest baeed exclualvely on the l5-year unlnEerrupEed uee of larvtcldes. No cage of chlorphoxlo reelaEance hae yet been denonetrated 1n t,he eavanna epecles. Tenephoe regletance ln S. Sanctlpaull ln the lnltlal Prograome area haa renalned stable ln lntenslty and dlstrtbutlon. 3. Screenlng of new for-nulatlq1ts and rlver trtale 3.1. B. thurlnglenela H-14 Sandoz: The reeulte of the acreentng of 36 eanplea (table 3, page 3 co 9) sent Uy tfi-o-opany (two of whlch had a 1002 efflcacy aE o.4 urgll.llo mln.) enabled then Eo develop four experlnenEal fornulat,lons of Sc 98 (P 2 to 8) (Tab1e 1, page 1, 2) of whlch 50 lltres of each were sent for rlver trtals (Table 2, page 1, 2 and 3) of whlch one of Eheae four fornulatlons wae eelecEed (Sc 98 2O3-P2). Its efflcacy ls 1OOZ at O.4 nglLllo mln. and lcs carry at least equal to thac of HPD. It can be applled wlthout prlor dllutlon and renalna effectlve even ln hlghly turbld watere, whlch ls a greaE advantage for EreaEnente durlng the ralny 8€88orlo A batch of 5rO0O llrrea of thle fornulatlon, called Teknar IIPD 6000, hae been ordered for an operatlonal trlal which w111, BtarElng fron the end of June 1987, be conducted on the lower Bandaoa (Cote drlvolre). The company le currenEly worklng on the developuenE of Eore concentrated products. AbbotE: Fron a promlslng sanple tested ln 1986 ABG 6193 BR), elx neu foruula- tlons were produced and teeEed (tabLe 3, page 1) two of whlch were selected for rlver trlals (ABG 6193 BA and BD). Thelr efflcacy le 1OOZ at 1.2 ureltltO mln. and thelr phyelcal characterlsclce cooparable Eo Ehose of HPD (Table 2, pages 3 and 4). Subsequently, a bacch of 5'OOO lltree of one of these fornulaElona lraa eupplled (Veccobac 12 AS) to be teeted ln parallel wlth HPD durtng an operatlonal trtal on the lower Bandaoa. Thelr efflcacy proved to be qulEe couparable and Abbot wae aeked t,o tender for the eecond order for larvtcldee for 1987. -3- Slnce then, 16 other aanplee have been provlded by the coupany and t,eated (table1, pagee 2 - 4) of shlch at tea8t one ls very proulalng (barch 6221 94-O1O-BR - IOOZ efflcacy at O.4 ur$lLlLo nln. and aceeptable phyelcal characterletlee). One hundredlltree of thle fornulatlon (Vectobac 24 AS) were sent for a rlver trlal but qulte recently the conpany declded Eo eent,5rooo llcree lnmedlately for an operatlonaltrlal whlch w111 be carrled out ln parallel wlth HPD 6O0O on Ehe lower Bandama. --- Solr?{: Fourt,een nel fornulatlona were tesEed (Table 1, page 2 and table 3, pagelL) and 50 lltree of two nore prorlslng onee were Bent for a rlver trlal. The resulEe were dlsappolntlng; no new formulatlon ls currently belng evaluated (Table2, page 4). Mtscellaneous 3 were-IEeE- eff-eErIve 1, pages I and 2). Ttro conpanlee (Mlcroblal Reaources and Fltc) Bent Banplee shlch than HPD. They have been aeked to eend other foruulat,lone (Table 3.1.1. Influence of turbldlty on eff lcacy of B.t. H-14 foroulatlone To ensure hat rhe new, tllore actlve, I€. H-14 formulatlone were not ooresenelttve to t,he lnfluence of turbldlty than the earller one, a test waa carrLed out wlch arclflclal turbldity (Kaolln) and the Sandoz 6000 P2 formulaclon. The reeulte, shown ln Table 3, page 10, ehow a ellght reduct,ton ln efftcaclty at turbldltlee of 18O JTU and above (equlvalent to roughly l5O ng/l of kaolln). ihls h.e no oPeratlonal algnlflcance elnce fleld turbldltlee even ln che ratny Eeason, rarely exceed 50 JTU. 3.2. Conventlonal chenical larvlcldee The OCP Insectlcide Reeearch Unlt nos hae a good fleld sEatton tn Cotedrlvotre that nakea lt poselble to carry out Er1a18 on a enall ecale throughout the /Galo 1:?.1: or8?$gphosphorue conpounds: only one new product has been tested: oMS 3036CELAMERCKT 4ST.EC)i unfortunately lE has been nlthdrawn by the conpany even thoughlc gave relatlvely pronlelng reeulte 1n troughe and durlng rlver trlals (Table 4,page 6 and Table 5, page 2). 3.2.2. carbanatess__Tlrree experlmental 5oZ EC fornulatlone of carboeulfan (ltarshal) Y9r" tesETt@allel wlth Lne ZSZ EC foruularton already ueed in rhe prograuoe(Table 4, page 1). one of then wae eelected and Ehe rlver trlals ahowed thit lteactlvlty wae equlvalent to that of the 252 fornulatlon (Table 5, page 1). t{lch onlya quantlt,y of 6o cc/n3/sec to be applled, the use of thle fornulatlon gtves greater auEonooy co the alrcrafE. 5'5OO lltree of lt have been ordered for thi tr.rtrent ofthe hlgh watere durlng the 1987 ralny 6eaaon. 3.2.3. Pyrethrotds Permethrtn: Nlne new fornulatlons have been teaEed lncludlng: fornulatlone t,haE are not very effecttve (table 4,two mlcro-encapeulated3); two formulatlone eynergleed by plperonyl butoxlde t,hat are noc oore effect,tvethan the fornulatlons used operattonally (Table 4, pages 3 and 4); PaSe , ll l. -4- flve other fornulatlona tso of whlch - Pounce (257, EC) frou FMC and Iuperator(252 EC) fron ICI - gave good reeulte 1o troughe and durlng rlver trlalB (Table 4, pagee 2 and 3, Table 5, page 1). 2,800 lttree of the flrat whlch le apparently leee toxlc to non-targel tnvertebratee than the eecond have been ordered for the t,reatoenE of the htgh watere durlng the ralny B€a8ooo aeven other pyrethrolde, uoat of then belonglng to the -cyano group eere teeted of shlch flve proved to be aufflclently effectlve to JuBElfy rlver trlals(Table 4, pages 4 to 6). Thle waE done for tco of theus cyphenothrln (Kltaht) aod allethrln (Pynamln Forte) fron Suultooo (table 5, pagea 1 and 2) whlch appeared to be too toxtc agalnat norFtarget organleu. 3.3. Ineect Growth Regulatora The methodology for the Eesttng of theae products hae now been well developed. The rat,ee of recuperatlon of the adulce ln the control batchee are usually above 802. Ftve dlfferenc producte have been t,ested (No.14/IPR/Rap/87 - Annex 1) only one of whlch 18 ney. Nes reeulta have conflroed thoee obtalned eo farr l.€.3 che efflcacy of the Juvenolde la Sreater oa old than on youog larvae; Ehe dlfference aB regarde the effectlve doee le abouE teo tlues; better reeulta are obtalned wlth a prolonged contacE Elue (60 nln. or nore); there le great varlablllty ln the reaulte. Two Juvenolde that are effectlve on old larvae at a dose of O.1 to 0.125 og/1/10 mln. are to be the eubJect of Bpot rlver trlala: OMS 3019 (1OZ EC, Sunltomo) and Phenoxycarb (2OZ EC, Maag). Although theae two productE have only llulted efftcacy, theae trlals have been envleaged ualnly fron Ehe vlevpolnt of nethodology (type of exposure, frequency, evaluatlon of Ehe reeults, etc.). A new foruulatlon of dlflubenzuron (52 EC of Dtnllln R, Dor Cheulcal) dld not prove to be oore effectlve than the uany fornulaElone of thle product teatedprevlously. The eaue appllee to a new ecdyeold, OMS 3031 (52 EC, Dow Chenlcal) shlch alao gave poor but 8t111 uore varlable reeulta. Fo1lowlng the recoonendatlone oade durlng the prevlous Eeetlng, Merck Sharp and Dohne sae asked to provlde an euulelftable concentrate of lvdroectln for addltlonal trlals but lt hae noE replled to thlo requeot. Averuectin rematne, hovever, one of the nogt effecclve larvlcldes teated ao far. 4 Effecte on non-tar8et aquatlc invertebratea 1i. ti a The preeence of a hydroblologlat coneulcant at the Ineectlclde Reeearch Unlt allosed lncreaelng Lhe number of studlea concerntng the non-target fauna. 4.1. Fornulatlone of B.E. lF14 Earller reeulte wlth the orlglnal Sandoz Teknar at Ehe Elne of lt,s lntroductlon ln 1981 lndicated that lt sae very lnoffenelve to the non-terget fauna. However the newer operaElonal fornulatlone (Sandoz E-D, AbboEt 12AS) had not been tested, nor had the very prootelng Sandoz experlnental fornulatlons. To enaure that a toxlc fornulatlon conponent had not been lntroduced, lt wae declded to test theee foruulatlons at thelr operatlonal dosee aod at overdoses. -5- In general the Producto are very lnoffenelve to the non-target fauna (Tablee 7,7a). The teete were run ln two eerlea: all the Sandoz -6O0O' producte, and the Teknar and Vectobac 12AS fornulatlono two days later. Severat blologlcal andhydrologlcal event,s' not relat,ed to the lneectlctdes tested, lnfluenced the te8te.The naln probleus wlth lncreaeed drlft occurred 1O houre after Ehe lnaecclcldetreatnent. The data ls preeented for the regular 24 hour gutter test (Table 7) andfor a IO hour teat (Table 7a). 4.2. Chenlcal larvlcldes Result,s of gutter teets wlth claselcal chenlcal compounds are preaent,ed tn Tablea8 and 9. The data ln the latter table wae produced by the OCP hydioblologlat who was unforcunately unable to attend the neetlng. The eerlee of teote of Eenephoe at the top of Table 8 eetabllshed Ehat temephoeforuulat,ed by Phytagrl le equlvalent to the operattonal product frou proctda, ." f." as the non-targeE fauna le concerned. Chlorphoxlo daEa are provtded ae a couparlson. A serles of peruethrln fornulatlona were tested ln whlch sone were found to be equlvalenE to the operatlonal fornulatlone (Table 8) . One product, Imperatot (251 EC) fron ICI, raa found to be oore toxlc, baaed on one tegt. A eerlee of other pyrethrolde sere t,egted (Table 6); Eoat seened to be as toxlcor more toxic chan pernethrln. A flnal aerles of tests ls planned before decldlng if one of the alpha-cyano eubsElcuted pyrethrolde ehould be teited on a larger ecale. OMS 3036' a net, organophoephate, !ra8 EeaEed and found Eo be nore (though not unacceptably) toxlc than tenephos at an operarlonal doee (table 9). ire wlttrdrawalby the nanufacturer scopped Erlale. Flna1ly, carboeulfan waa teeted at 5OZ above the operaclonal doae of o.O5O ng/l/lo En. It seeme that a ellght overdoee doee not slgnlflcantly lncreaae non-target lnverEebrate drlft (Table 9). 4.3 Chltln Synthesle Inhlbltor A pllou ecudy wlth dlflubenzuron (Dlnl1ln 12 EC, Dow Chenlcal Co. ) waa conductedwlth non-target lnverEebrateg. Unforcunately, another toxlcant was lnt,roduced theday after treatmenc lnto the Etrean by locaI fleheroen. Reeulta are thereforedlfflcult to ettrlbuEe to Ehe dlflubenzuron alone. The energence cages dld notfunctton well and have been redealgned. Data were analyzed baeed on drlft. The addltlonal toxlcant wae ln the rtver 5.5 Eo 18.5 houre after the treatnent was applled. After 4.5 days, ralnstorme ln the area affected the rrater levele ln theLest system, and the test wae ternlnated after Een days (Table 1O). Trlcorythldae(Epheneropcera) nynphs and Pyralldae (Lepldoptera) lirvae exhlblted algne that Eaybe attrlbuced to the chlEln synthegle lnhlblcor. The overall effecc on the non-target, fauna was mlld; the uaJorlty of Ehe drlftlng was due Eo t,he second toxlcanr, changlng water levels and the length of che experlment. 4.4 Effeccs of water cenperature on toxlclty of lneectlcldes Although wlth tenephoa, whoee toxlclEy lncreaees wlth temperature, Ehe effect of ceEPerature on other operattonal lneecElcldee had not been analyeed ln detall by ocp.The effect of che water temperature on the coxlclty of lneectlcldes varlee.Prellnlnary reeulta were presented uslng pooled data of peruethrln and carbosulfan tal. -6- fornulatlona to denonstrate the prlnclple of water tenperature belng partlally reeponeible for the varlatlon ln non-target gutter teots. A knowledge of Ehe effecta of tenperature (treatnent and poet-treatuent) on non-target Eortallty would be ueeful ln protectlng the envlronnent fron a more aevere lupact than neceooarlo Further analyeee on this aopect le sttll belng done at, the IRU at Bouake (eee also para 5.4). 4.5 Data recordlng A eet of etandard reportlng forne hae been establlehed for the non-terget gutter teets ln vles of settlng up a nore convenlent data flllng B]BteEo 5. Addltlonal reeearch 5.1. Methodolony and ecreening devtcee The troughe eyetem le ueed to tesE claaalc chenlcal larvlcldee and that of the nlnlgutters for B.t. H-14 fornulatlone. In order to lncrease the capaclty of the ecreenlng wlth the troughe, lt wae envleaged to uae a hybrld Blat€no However, thla EyBteD hae not been adopted because the oortallty obtalned ls lees than that obaerved both ln troughs and ln the fleld (Table 11 and L2, Graphe 1 and 2). The devlce for the evaluatlon of lnsect growth regulators has been lmproved espectally ln regard t,o the colonlzatlon of the Bubstratee by larvae and Ehelr observat,lon after treatnent. In lte preeent foru, thls devlce now glves eatlefactlon. 5.2. Phyeloloclcal nechanleme of reeletance The ongolng Btudlee have conflrned the role of esteraeee ln the reeletance to the organophoephorue compounde. However, the reeletance to chlorphoxin ls due nalnly to an oxydaee. Teste baeed on enz]rme Btalnlngg do not succeed wlth blackfly larvae becauee the enzyne tltre8 are too low even regardlng htghly reeletant larvae. Addltlonal trlale are betng carrled out as well aa others baeed on che use of DNA probes developed for noequlto realstanc€ €ozln€Bo Studlee are alao belng conducted to compare the resletance mechanlsne of the Bavanna and foreet speclee of the S. damnoeun complex. 5.3. Studtee on reelduee These studies, atarted tn 1985 t lth permethrtn, rrere continued ln 1986 wlth the four chentcal larvlcldee utlllzed by the Programe. At the end of the flrst serles of treatnente, the quantltles detected sere very lor (at the llnit of the chreehold of detectlon) ulth the exceptlon of pernethrln on the lower Sassandra (Cotedrlvolre). However, elx monEhe later the concentratlon was very low agaln (42 ug/kg of dry eedlment) (Table 13 pagee I ro 3). Slnce theee etudlee are very coetly, lt 18 noE envlaaged to repeat then aa long aB the Progranne doee not uae e new tneecttclde. Thle recoomendatlon lraa nade by the Eeologlcal Group alao. 5.4. Study of the cerry of larvl.cldee ln runnlnq uatera The flrat reaulte obtalned by the Bltlng Ineects Reeearch Group (GRIP, Quebec) have nade lt poeetble to deflne a relatlonehlp between dlecharge and the carry ofB.t. H-14 for certaln typee of rlvere. A uatheoet(cal nodel lntegratlng both -7 - blologlcal (eueceptlbltlty model) and hydrologleal (larvLcldes carry oodeL) data hae been developed. Thte uodel wl11 be finallzed eoon and lncegraEed operatlonally. In 1te flnal foru, lE w111 aleo lnclude the optlolzstlon of Ehe treaEmenE ctrcutEs parttcularly accordlng to the chotce of larvlcldee and logletlc and hydrologtcal paraoetera. The flret reaulca obtalned tn thla fleld and thelr proepecte for practlcal appllcatlon are already very pronlelng. Aa part, of che developuent of a larvae suacepElblllty uodel, aone lnformaElon haa been obEained concernlng parttcularly: the relatlonshlp beEseen water temperature and efflcacy of the larvlcldes. A negattve correlaElon hae been obeerved wlth perneEhrln whlch, beyond 3OoC, eeee lte efflcacy dlnlnlsh greaLly (Table 14, Graph 3). Thla faccor Euat know be taken lnto accounE ln the progranmlng of operat,lorurl treatnenEe. ln Btudtes of contact tloe/concentratlon reclproclty (Table 15) chlorphoxlm, peroethrln, and tenephoe all ehow an apparent fallure of rectproclEy after 2O or 30 ulnutes. However, the effect at long expoaure tloee nay be due to degradaclon slnce the lneectlclde was ln contact, wlth water for a prolonged perlod. FurEher experloent are planned to clarlfy Ehe eltuatlon. Theee data also conflrn Ehat a mlntnuu contact t,tne of about 5 mtn, la requtred for Eeoephoe to act. t{lth a one ulnute contact, only 6.22 nortallEy uae achleved, veraua 83.42 after 5 mln. although che toxlclty of tenephoe changes very lltc1e wlch the clne after ulxlng wlth water up to 12 houre (Table 16), there le a large tncreage 1n nortallty aB Ehe proportlon of wat,er ln the nlxture le lncreaeed (compare eotutlone A and B at 0.025 ng/l ln Table 16). Thle phenonenon, whlch neede to be explalned, could accounL, at least ln part, for the renarkable carry of uenephos srhlch greatly exceedg that of all the other larvlcldeo utlllzed by OCP. Concluelons - Recoonendatlon The nunber of new lneectlctdee produced each year by the lndueEry conElnuea to decreaee, whet,her ln regard to claeetc lneectlcldee or lnsect growth regulators. The analyele of thle report reflects thts Erend welL. Much tlme hae been devoted to the evaluatlon of pyrethrolds, eepeclally varloue peroethrln fornulatlone. The proepecte of sE111 flndlng more effectlve, nore aelectlve and less costly pernethrln foruulaEtons are now very llnlced and efforte ln thls regard w111 be reduced conslderably. Ln vlew of che very low voluoes applled wlth respecc to Ehle product, Ehe actlve-lngredlenE concentratlon of the formulat,lone should not exceed 257 (betcer appllcatlon posslblllules, leee dangerous accldental overdosagee, lese costly produce loesee). In the absence of peroethrln reelatance, the uee of eynerglzed foruulatlone le not, envlsaged. On the oEher hand, 1n caee of fall ln eueceptlblllty, the effect of eynergtscs such ae plperonyl butoxlde whlch, evenEually, could prolong Ehe uae of perneEhrln or pyrethrolde ln general w111 be evaluaEed. The advleablllty of further developlng pyrethrolde le queetlonable. Although ooat of theu belong to the alpha-cyano atructural group and are therefore conetderably dlfferenE from pernethrln, lt 18 lupoeelble t,o predlct whether reelaBance Eo pernethrln stll lead Eo croaa-reetatance wlch the coopounds of thls group or not. Although the general croes-reeletance prospecta regardlng pyrethrolds aa a uhole are racher unfavourable, lE has been dectded to teat, ln parallel and on a reduced scale, three or four larvlcldes of che alpha-cyano group and montt,or closely thelr effect on the non-target, fauna. Theee producte w111 be put ln reaerve -8- and thelr eventual uge 1111 be dlecueeed ulth the Ecologlcal Group ln case of reeleEance Eo pernethrln. Accordtngly, tt would be deelrable to conEact the Ecologlcal Group nos to develop a mlnlnuu protocol for rtver Erlal of pyrethrotd larvlcldee of Ehe alpha-cyano grouP. As maEters eEand at presenE, llCtle ls to be expected from lnsecE growth regulaEor coupounds and Ehe prlorlEy accorded to reeearch ln Chts fleld ehould be llmlted. However, lt le deslrable to oalnEaln thls reaearch aE a certaln level ln order Eo contlnue Eestlng new products 8111 Che conelderable dlfferencea ln efflcacy of theee products wlth reepecE Eo uoequlEo and blackfly larvae are explalned. The proepecte ln Ehe fleld of other groupo of claselc chemtcal larvlcldee are alao very llntted elnce Eost of the known products have already been t,eeted. However, should new lnsecclcldee ln the HIIOPES prove to be very toxlc for Eosqulto larvae, lt would be deslrable to teet Ehelr efftcacy agalneE larvae of the S. daonosuu complex even lf lE ls a long and coeEl1r proc€aao The mosE lntereet,lng resulEs obtalned concern Ehe lnprovetrenE of the perfornance of B. thurlngtenals H-14. Fornulatlons three Elnee nore effectlve than HP-D(0.@stead of 1.2) when tested on a sma11 scale w111 be evaluat,ed operaElonally ln the near future. The conpetltlon beEween the conpanles hae led, very recently, t,o a decreaee of almoeE 5OZ ln the prlcee. It ls very probable that the lndustry could ln future produce nore effecElve foroular,lons. The preeent prlce ($ 6.5/lltre) of IIP-D equlvalent could fall by between 2O and 3OZ through the conpetlElon between the new formulattone currently belng evaluat,ed operaElonally. WlEh a formulaclon such ae Vectobac 24 AS or HP-D 6OO0 at g 3.O/11tre, Ehe use of B.E H-14 would no longer be rnore coaEly uhan that of tenephoe ln che ratny aeaaon and-Iesa costLy ln the dry eeaeon (Graph 4). Although th18 staEe haa not yef been reached, the recent evolutlone ln thle field nake lt poeelble Eo chlnk EhaE lt could be eo ln the near future. They open up nel prospecEs, eepeclally ae regarda Che exEenalon of the treaEed areaa Eosards che l{eet and South-€agto qc"i;dflntlm' Gi. Annexe: I OCP: M. B. Inat,ltut PIERRE RICHET: LISTE DES PARTICIPANTS M. A. Akpoboua, Chef Secteur/Bouake T. Barro, IRU/BoUAIG J. Grunerald, COOR/AREM, Banako (Rapporceur) P. Gulllet, Chef I{OA, Banako (Rapporceur) J. P. Gulllotin, ADM, Ouagadougou J. Henderlckx, AEROPS, Kara D. Kurtak, Chef IRU Bouake R. Meyer, IRU Bouake M. Ocran, IRU, Bouake M. Ouedraogo, IRU, Bouake D. Partrldge, STC/AEROPS, Odlenne . Poudtougo, AEROPS, Odlenne . Renaud, IRU, Bouake . Sarr, AdJolnt Chef Secteur, Bouake . YamagaEa, EOA, Kara t{ahle, STC/IRU, Bouake M. l,l. M. M. M. M. M. M. M. M. M. M. M. M. P P M Y (o.c.c.G.E. ) M. J. Doannlo, Bouake M. J. Dogsou-Yovo, Bouake M. J. Duval, Bouake Supportlng docunenta: Table I - 16 Graphe 1 - 4Map 1 IPR Reporc: 14/IPR/RAP/87 (annex 1) ll Chef VCU M. P. PangaleE M. J. Henderlckx Dr D. KurEak M. R. Meyer M. L. Yameogo M. M. Ouedraogo M. M. Ocran M. P. Renaud M. P. Gulllet M. T. Barro OCP Llalson Dr G. Quelennec Dr R. Baker M. Doannlo M. J. Doesou Dr J. F. l{alsh Dr J. Grunewald M. B. I{ahle Dr Y. Yanagata Dr C. Leveque Dr N. Gtatz Dr D. A. T. Baldry Revlew Eeetlng Banako Odlenne Kara Bouake Bouake Ouaga Bouake Bouake Bouake Bamako Bouake Geneva (Mr J.D.M. Marr) Geneva Bamako IPR IPR Kara Bauako Bouake Kara(Ecologlcal Group)(E.A.C. ) VCU Ouaga (for local dlscrlburlon) Dtstrlbutlon ll . \ a (' \o@o\{L (') Bo I I T rfl(n6ilzo m (, -{ {C @ 6@{ oZ Iouo; ,n -tn c)o2 -{7o - 3odlu - -n - t a ,rta (D tJ) = ! m c,m7 c)oti m I =ti - 766)6 - c, @ an vr =Im E oq I 'l 6 !vo6)fr - -r I m rj m oo - t m F \ \ \f ! au og. o oE a o o. , j...: :%:a n od eo a oI oT'E t.r(n u6e E *ti Ooi d *Q teid EE 3ila Eg3 od oco qB \@ e r :.. \ 'l' J ( ,ti |@ -{' ].