ANNEX 2 ADDITIONAL OBJECTIVES. Objectives achieved and work carried out in addition to the agreed programme of work of OPEN Contract 0167

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1 ANNEX 2 ADDITIONAL OBJECTIVES Ojectives chieved nd work crried out in ddition to the greed progrmme of work of OPEN Contrct

2 6. OBJECTIVE 6. Effects of copper fungicide tretments on the minerl composition of potto tuers nd soil copper concentrtions The investigtion reported under section 6 ws crried out in ddition to the greed progrmme of work under Open Contrct OF Introduction The world consumption of copper (Cu) compounds is round 200,000 tonnes per yer, of which pproximtely 75% is used in griculture. Cupric oxide, cuprous oxide, copper cette, cupric chloride, copper oxychloride, cupric nitrte nd copper npthente re used s either minerl fertiliser or for their fungicidl ctivity. Copper is n essentil element in metolic processes nd required for growth nd reproduction of ll higher plnts nd nimls. Yield losses of up to 20% cn result from unrecognized (suclinicl) copper deficiency, in mny crops without the ppernce of Cudeficiency symptoms. Coppercompounds used s fungicides include copper sulphte, copper oxychloride, cuprous oxide, copper hydroxide nd copper mmonium cette. Copper fungicides re rod spectrum protective fungicides with low risk of resistnce development y fungl pthogens. No resistnce hs een found so fr nd since copper ffects fungl metolism through multiple mechnisms it is thought unlikely tht Cutolernt or resistnt pthogen strins will develop. Copper relesed from copper fungicides cts s fungicide y denturing proteins nd enzymes within fungl spores nd hyphe. Spores ctively ccumulte copper nd germintion is inhiited, even t very low concentrtions. Copper fungicides re widely used to control rnge of common diseses; nthrcnose, rust, lef spot s well s downy mildew diseses nd erly nd lte light on vegetles, tree crops nd on ornmentls. In pottoes copper fungicides re minly used to control lte light. For the mintennce nd expnsion of glol griculturl productivity levels, regulr nd frequent ppliction of Cused fungicides re thought to e essentil. This is prticulrly so in orgnic production systems, where t the present time, copper minerl fertiliser is permitted, while Cu fungicide use is prohiited. However, derogtions currently llow orgnic frmers to use Cu fungicides in mny EU countries. Environmentl contmintion of soils with Cu, my e cused y industril pollution ut is usully cused y the use of grochemicls contining this hevy metl. The min source of contmintion is from folir Cu ppliction mde to control plnt diseses through direct ppliction, drift, or dripping of excess sprys from lef surfces. In orchrd production systems (e.g. pple, grpevine) repeted using of copper fungicide (severl pplictions every yer) were shown to led in the long term to significnt ccumultions of Cu in the soil surfce horizons. Accumultions of up to 800mg Cu/kg soil in the upper prt of the soil profile hve een oserved in orchrd crops such s pple nd grpevine, whilst concentrtions s low s 1234 mg/kg hve een shown to hve negtive impct on soil iologicl ctivity. For exmple, Cu ccumultion in surfce horizons my hve potentil detrimentl effect upon rnge of eneficil soil orgnisms, including erthworms. This ccumultion in top soil lso corresponds to the zone in the soil profile with gretest iologicl ctivity; mycorrhizl ssocitions, microil popultion density, nd hrours most of the soil mesofun. Erthworms my void surfce litter nd soil lyers contminted y certin pesticides including Cu fungicides. The worm Eiseni fetid (which is used in worm composting processes) ws shown to void soils with even reltively minor elevtion of copper 111

3 (44mg/kg) nd significnt voidnce y erthworms ws found when copper residues exceeded 100mg/kg. Erthworms re highly moile in soil nd hence their ility to void res of contmintion could hve significnt ecologicl implictions. Reported soil microil community responses to Cu contmintion from rnge of sources hve included reduced mount of microil iomss nd reduced microil respirtion rte. Mny studies hve een crried out on the effect of copper fungicides use in orchrd production systems (e.g. pple nd grpevine). However, there hve een virtully no studies on the effect of copper fungicide use on copper residue level in orgniclly mnged rle rottions. The min ojectives of the studies descried in section 6 were therefore to determine the effect of copper fungicide ppliction on: (i) The percentge dry mtter (% DM) of potto tuers, (ii) potto tuer minerl composition nd (iii) Curesidue levels in orgniclly mnged soils Mterils nd methods Tuer nutrition nlysis In 2001, the four vrieties of included potto included in trils were , Eve Blfour, Snte nd Nicol. In 2002, the six vrieties of potto studied were , 87418, , Eve Blfour, Snte nd Nicol. The detils of nlyses crried out to determine the percentge dry mtter (%DM) nd minerl composition of potto tuers were s descried in section 3.7 in the Brynmor Thoms Lortory, School of Agriculture Food nd Rurl Development, University of Newcstle upon Tyne. However, in 2002 no nlysis of nitrogen content could e crried out ecuse the equipment in the Brynmor Thoms Lortory ws out of order. The ssessment used the stndrd method nd protocol pulished y the Ministry of Agriculture, Fisheries nd Food. Soil copper nlysis Soil smples for susequent copper nlysis were tken from field trils in oth 2001 nd The detils of field sites were descried in section 4.2. The smpling ws done twice; the first smpling ws tken fter the lst copper oxychloride spry nd the second fter hrvesting (There ws n intervl of pproximtely 7 weeks in 2001 nd 6 weeks in 2002 etween the finl ppliction of copper oxychloride nd hrvest). The soil smples were tken rndomly from the top 10 cm of soil in 6 replicted res from ech copper treted soil nd untreted soil. The time tle nd mount of copper pplied were s descried in section 3.5. nd tle 4.2. Aville copper concentrtions in soil were determined y commercil lortory (Beverley nlyticl lortories Ltd.) in 2001 nd in the Brynmore Thoms lortory in In oth yers stndrd soil extrction nd mssspectroscopy protocols were used the stndrd method nd protocol pulished y the Ministry of Agriculture, Fisheries nd Food (1973) (see ANNEX 3). 112

4 6.3 Results Effects of copper oxychloride fungicide ppliction on potto tuer dry mtter (%DM) content There were differences in the percentge dry mtter (%DM) of potto tuers etween vrieties in oth field trils (Figure 6.3.1). The %DM in the erly mturity vriety Nicol ws lower thn in lte mturing vrieties; , nd However, the %DM of tuers treted with copper fungicide were not significntly different from untreted tuers. Effects of copper oxychloride fungicide ppliction on potto tuer composition Results of compositionl nlysis of potto tuers in 2001 nd 2002 showed tht potssium ws the mjor ction in potto tuers (Tle ). In 2001, only Fe levels were significntly different etween potto vrieties nd were gretest in Eve Blfour (Tle 6.3.2). There were no significnt differences etween levels of minerl nutrients etween tuers of copper treted nd non treted tuers in ll vrieties of potto. In 2002, there were more mrked differences etween vrieties. There were significnt differences (P<0.01) in P, K, C, Cu, Mg nd Mn contents etween vrieties of potto (Tle 6.3.2). There were lso significnt differences etween locks in K, Cu nd Fe (dt not shown) There were differences in K nd N etween copper treted nd untreted tuers (Tle 6.3.3). Tuers from some vrieties tht hd not een treted with copper fungicide contined higher levels of K nd N thn tuers from untreted crops. On verge, % K ws 1.85 nd 1.72 nd % N ws 0.52 nd 0.50 for non copper treted nd copper treted tuers respectively (Tle 6.3.3). For tuer levels of clcium there were lso very ig differences etween the 2 sites, which is most likely to e due to differences in soil Clevels etween the 2 sites. Clcium levels in the Stndfield Hll frm soils were 4733 mg kg 1 while concentrtions in the Nfferton frm soil were 1847 mg kg

5 () Tuer DM % Copper spry No copper spry 0 Nicol Eve Blfour Snte () Potto vrieties Tuer DM% c c d 0 Nicol Eve Blfour Snte Potto vrieties Figure 6,3.1. Percentge DM of potto tuers of different vrieties in () 2001 nd () Different letters indicte highly significnt differences (P<0.01) etween vrieties ccording to Tukey s Honestly Significnt Difference (HSD) test. 114

6 Tle Minerl composition of potto tuers (% DM) from copper fungicide treted nd untreted crops of different potto vrieties in 2001 nd The first line in ech row shows the results in 2001 nd the second line shows the results in Tuer nutrient Copper tretments Nicol Eve Blfour Potto vrieties Snte N 1* ** P K C Cu Fe 1* ** Mg Mn N *= Copper spry 2**= Non copper spry 115

7 Tle Contents of Fe, P, K, C, Mg nd Mn in different vrieties of potto tuer in 2001 nd 2002 (s %DM). Different letters indicte significnt differences (P<0.05) etween vrieties ccording to Tukey s Honestly Significnt Difference (HSD) test. Element Yer Nicol Minerl composition of potto tuers (%DM) Potto vrieties Eve Snte SE Blfour Fe P K C Mg c c c Mn Tle Effect of copper fungicide tretment on P nd N in potto tuers in Different letters indicte highly significnt differences (P<0.01) etween vrieties ccording to Tukey s Honestly Significnt Difference (HSD) test. Minerl composition in potto tuers (%DM) Copper spry Copper tretments No copper spry SE K N

8 Effects of copper oxychloride fungicide ppliction on the copper concentrtion in potto tuers There ws no significnt difference etween tuers from crops treted with copper fungicide nd non treted tuers. Copper levels in potto tuers were generlly low (Tle 6.3.4). Tle Copper concentrtion in potto tuers of different vrieties in 2001nd in Yer Potto vrieties Copper treted tuers Copper concentrtion in potto tuers (ppm) Non copper treted tuers SE Copper treted tuers Non copper treted tuers Nicol Eve Blfour Snte SE 117

9 Effects of copper oxychloride fungicide ppliction on levels of copper ville in soil There were significnt differences in levels of copper ville in soil etween copper treted nd untreted plnts oth in 2001 nd Copper ville in copper treted soil ws higher thn in no copper treted soil. However, there were no differences etween first nd second nlysis (t the time of the lst fungicide ppliction nd hrvest respectively) (Figure.6.3.2). Copper ville in 2001 were pproximtely 4 times higher thn in 2002 (Figure 6.3.2), proly ecuse the quntity of copper oxychloride spryed in 2001 ws pproximtely 2.5 times higher thn tht pplied in Aville Culevels used in trils in 2001 (Pickering) were 5 times higher thn in the Nfferton frm soils used in 2002, which were extremely low in ville Cu. Copper residue in soil (ppm) Copper spry No copper spry 0 After lst ppliction After hrvesting After lst ppliction After hrvesting Figure Copper ville in soil t the time of the lst fungicide ppliction nd fter hrvesting in 2001 nd Discussion Appliction of copper fungicide hd no effect on the copper concentrtion nd the %DM in potto tuers in oth experiments. However, effects my occur if copper fungicides result in longer period of folige growth nd tuer ulking ecuse in generl tuer %DM increses s tuer mture. There were differences in %DM of potto tuers etween vrieties in oth sesons. The %DM in erly mturing vrieties such s Nicol ws lower thn in lte mturing vrieties; , nd reflecting different lengths of growing seson. It hs previously een reported tht lte mturing potto vrieties with longer growing seson re higher in dry mtter thn erly vrieties with shorter growing seson. 118

10 Anlysis in 2001 showed tht the only significnt difference in minerl composition etween potto vrieties ws the Fecontent. In contrst, in 2002 there were differences etween locks, copper treted nd non treted tuers nd lso etween potto vrieties. To lrge extent vritions in minerl composition in plnts depend on genetic fctors, ut tuers of the sme potto vriety, re known to vry in the content of prticulr components depending on environmentl fctor i.e. climtic nd soil conditions, wether nd growing conditions, such s fertiliztion, pesticides, diseses, etc. In ddition, minerl composition my e ffected y the ge nd mturity of potto tuers. The minerl sustnces ply importnt roles in potto tuer metolic processes nd enzymtic metolism. Some uthors reported tht some minerl elements (e.g. K) re correlted with resistnce to certin diseses nd influence the flvour of cooked pottoes nd discolortion of pottoes ftercooking. The following re exmples of the functions nd effects of some minerl sustnces on potto tuers; Potssium in potto tuers prticiptes in the regultion of the process of hexose condenstion resulting in sucrose nd strch formtion. Incresed potssium content in potto tuers is usully ssocited with incresed orgnic cid content; citric cid especilly is responsile for the decrese of ftercooking discolortions. A positive correltion is reported etween potssium content in potto tuers nd potto resistnce to lckspot. Sodium, like clcium nd potssium, is responsile for the control of electricl nd structurl properties of cytoplsm nd cellulr memrnes. Iron content in potto tuers is usully positively correlted with phosphorus content. Iron, in ssocition with chlorogenic cid, cused ftercooking discolortion of pottoes. It is likely tht the differences in the minerl composition of potto tuers oserved re due to vriety nd copper fungicide ppliction nd results re likely to reflect differences in metolic processes, enzymtic metolism, yield, tuer qulities, flvour nd possily disese resistnce. However, little is known out effects of copper fungicides on minerl composition of potto tuers nd more reserch is needed on effects copper fungicides on potto tuer qulities, flvour nd the qulities of tuers fter cooking. There ws difference in copper residue in soil etween copper treted nd non treted plots. However, there ws no difference etween the first nd second smpling. This ws not surprising since copper ccumultion or decline in soil re long term processes. However, compred to the Curesidue levels recorded in other experiments (those involving orchrd crops), which hd negtive effects soil flor nd fun, the rise in ville soil Culevels recorded in experiments (< 4 ppm), ws too low to result in significnt negtive effects on soil iologicl ctivity. However, if the soil were to continue to receive copper fungicides t the level used regulrly yer fter yer (e.g. s common prctice in perennil or orchrd crops) the copper residue could ecome high enough to dmge soil flor nd fun popultions, since it tke long time for copper residue to decline. 119