Control of Medfly by SIT in the Nereva River Valley

Fruit Flies of Economic Importance: From Basic to Applied Knowledge Proceedings of the 7th International Symposium on Fruit Flies of Economic Importance 10-15 September 2006, Salvador, Brazil pp. 255-259 Control of Medfly by SIT in the Nereva River Valley

Mario Bjeliš*,Višnja Ljubetić**, Nevenka Novosel*** * Institut for Plant Protection in Agriculture and Foresty of Republic of Croatia, Zagreb, Zvonimirova 14 A,21210 Solin, [email protected] ** Ministry of Agriculture, Forestry and Watter Managment of Republic of Croatia, Vukovarska 78, Zagreb *** State Office for Nuclear Safety, Frankopanska 11, Zagreb, Croatia

Key Words: Medfly, SIT, Neretva valley, Croatia, Bosnia and Herzegovina 1. Introduction well as some islands (Vis, Hvar, Brač and Ela- phyte archipelago), are geographically iso- The medfly, Ceratitis capitata Wied. is a pest lated or have some isolated areas of interest of great economic importance in the area of and as such are highly convenient for the use Dalmacija region. It has been present in the of SIT ( Bjeliš and Pelicarić, 2003.). littoral regions for over 50 years (Kovačevć, The Neretva river valley seems to be to date, 1960.). In some areas, such as southern part the best candidate for an area-wide medfly surrounding the city of Dubrovnik, the pre- suppression programme using the SIT. The sence of the medfly precludes fresh fruit whole valley represents 80% of the national production, even when chemical control citrus production. The valley has been classi- measures are applied (Bjeliš and Pelicarić, fied as «international aquatic reserve», where 2002.). To date, the medfly is present in the more than 300 birds types has been recor- whole Dalmacija and in northern part of ded (Rucner, 1993.) and due to the presence Istria (Pelicarić and Bjeliš 2002.). As it is often of some other endangered aquatic species, the case worldwide, optimum conditions for and it is divided between Croatia and Bosnia medfly are found in backyards where several & Herzegovina. For these reasons, the area- host plants are grown, allowing the medfly to wide and transboundary use of SIT seems be present from late spring until the winter. to be the most suitable solution for medfly Althow medfly was not managed in the past, suppression. Neretva Delta region is an area some observations on possibilities for con- with the largest and most vaulable part of trol by using attractant were done (Šimunić, old Mediteranean wet-lands in Croatia ( Mar- 1960. , Brnetić, 1969.) kovčić, 2001.) and also one of few such are- The medfly has invaded the Neretva river as preserved in Europe. This is a natural unit valley, the most important mandarins, Citrus covering approximately total of 20.000 ha of reticulata production area of Croatia. De- land, from the area of the Hutovo Blato Na- pending on the area considered, the main ture Park (7.411 ha) in Bosnia and Herzego- hosts of the medfly in Croatia during the vina to spacious Neretva estuary (12.000 ha) fruiting season are loquat, early fig varieties, in Croatia. Croatian part of the lower Neretva stone fruits, late fig varieties, mandarin and valley contains 7 protected localities cove- kaki. ring 1,624 ha. Benefits of using SIT for the area-wide sup- The possibilities for organic farming prac- pression of the medfly have been investigat- tice exsist in small areas near the mountines ed. The Neretva river valley (Curić, 1994.), as that surround the valley, where water is not yet contaminated, such as Desne and Pojezer- Corresponding authors: je areas in Croatia, as well as areas bordering Mario Bjeliš Hutovo Blato Nature Park in Bosnia and Her-

Book Fruit Flies.indb 255 28/10/2008 08:27:56 256 From Basic to Applied Knowledge Since Neretva river valley is devided between Craotia and Bosnia and Herzegovina, regional program of medfly control by useing SIT should give the best control results.

zegovina.The cultures that can be cultivated from September gives more preferable hosts by using principles of ecological agriculture such as Japanese apple – Dyospiros kaki, manda- in both parts are traditionally grown medi- rins – Citrus reticulate etc. terranean and sub-mediterannean cultures Trapping data shows that the period of cap- such as citrus, japanese apple, kiwi, artichoke, tureS varies from earliest beginning of July until figs, peaches, almost all represent host plants end of December. for medfly. Trapping data from the Neretva river valley are Since the medfly infestation still raise, the shown in figure 2. On this area first captures can number of insecticide sprayings will increa- start from half August like it was in 2002. , or in se and only envinromental friendly methods the first decade of September like it was in 2003. such well developed SIT technique should be The location in Metković shows the highest used together with other organic methods captures during both years of observations and witch would not disrupt the present natural maximum of 269 flies per trap were recorded in balance (Bjeliš and Pelicarić 2003.). Baseline end of September / beginning of October. Much data collection on medfly biology is currently lower captures were recorded both at Opuzen undergoing, and a study is planned with the and Modrič locations. support of the IAEA TC project for the period The results shown in figure 3 shows that dur- 2007-2008. year, to assess the technical and ing four years of observation, the highest cap- economic feasibility of an area-wide SIT- ture were recorded at the Metković location, based medfly suppression program in the while much lower captures were recorded at Neretva Valley. Opuzen and Modrič locations. The hottest area has been defined around city of Metković, which is located on the border with 2. Area description Bosnia and Herzegovina, with numerous cultivated and ornamental host plants, with accent All tasks were chosen in the direction of col- on loquats – E. japonica at almost all city streets lection main elementary data about medfly and all kind of cultivated stone fruit trees. It biology, behavior, host preferable, seasonal should be expressed that across the state bor- occurrence etc. All this data are necessary for der in Bosnia and Hercegovina there are hun- further observations witch will be used for dreds of ha of peaches – P. persica, nectarines – the preparing the study of the sterile insect P.p. var nectarine and plumbs –P. domestica. program by using sterile males to control At some very infested orchards almost 250 medfly in the selected area, the Neretva river flies per trap were captured weekly. The lowest valley, as the most important economic citrus captures, less than 10 flies per trap weekly, were and environment endangered area. recorded at the lower part of the valley, where Numerous medfly host plants witch grows mostly mandarin orchards are placed. Small in whole region of Dalmacija shows possi- urban areas with higher number of host plants bilities that medfly can easily reproduce from around shows higher captures. May when first possible hosts are having Generally, two main areas can be defined. fruits like loquats – Eryobotria japonica and The lower part of the valley with mostly man- apricots – Prunus armeniaca. Later, more pref- darin crop and low medfly capture and higher erable hosts are available, such as peaches – part of the valley with numerous host plants Prunus persicae, nectarine – P.p.var nectarine and very high capture datas. In total, the treat- and special important and area wide present ment area in SIT suppression program could numerous fig – Ficus carica and wild fig – Fi- be estimated to up to 25-30.000 ha of join cus carica var caprificus. The period starting Croatian and BiH sides.

Book Fruit Flies.indb 256 28/10/2008 08:27:56 257 From Basic to Applied Knowledge Since Neretva river valley is devided between Craotia and Bosnia and Herzegovina, regional program of medfl y control by useing SIT should give the best control results.

The hypsometric map of the Croatian part 3. gEnErAl StrAtEgy of the river Neretva valley, shows great geographic isolation of whole area. It should be 2007-2008 (colaboration with IAEA tc expressed that very limited vegetation of 2006001): non-host plants has been recorded over 200- * Feasibility study of Medfl y Suppresion by 250 meter high. In lower parts, special in fi rst SIT in the Neretva Valley, 100-150 meter following medfl y host plants * Preparation of an economic feasibility study was recorded: wild fi g –Ficus carica var. caprifi - including the following scenarios: cus, wild berry – Prunus mahaleb and wild bri- - full production on site er (dog-rose berry) – Punnica spp. Also some - shipping of eggs weeds such as Solanum nigrum were recorded. - shipping of sterile pupae Higher areas of surrounding hills are almost * Regional grup trained for SIT operati- only stone. However, hilly areas should be tak- ons2009-2010: en into calculation of SIT releasing treatment. * Location for facility selected in the Neretva The temperature data collected for Neterva valley and surrounding areas were collected from * Location and administrative documentation different sources, but still represent average * Rearing/Eclosion facility build monthly temperature as an minimum one de- * Development of release system in aquatic cade data. Data were collected for Dalmatian areas locations Dubrovnik-Čibača, city of Ston, city 2011> of Split and city of Opuzen. * Start of the SIT suppresion programme

Figure 1: Popuplation dynamic of Ceratitis capitata in the different parts of the delta Neretva valley, during period 2002 - 2004 Year

Book Fruit Flies.indb 257 28/10/2008 08:27:57 258 From Basic to Applied Knowledge Since Neretva river valley is devided between Craotia and Bosnia and Herzegovina, regional program of medfl y control by useing SIT should give the best control results.

Figure 2: Medfl y capture on selected locations with different host availability in neretva river valley during september and october

4. concluSIonS mandarin was not attacked heavily. In other side, the upper part of the valley with differ- The results collected during the four years ent consist of host plants give to medfl y pos- observation period shows that medfl y can re- sibilities to create high population and create produce easily due to numerous host plants high damage on mandarins, witch represents available along the Dalmacija region. Also, small part of total crop in the area. The den- there are no data about period when fi rst sity of the medfl y is the highest in the upper adults emerge after winter period. Results part, specialy by the border with Bosnia and show that the earliest capture were recorded Herzegovina. This indicates to necessity of in early July, what can be explained by very join action program of medfl y suppression in low medfl y population before July. The results this part of the valley. show that medfl y reproduce very quickly and The hypsometric data show possibility even yearly peak of population is very similar in all to divide the valley to two separated sectors areas observed, defi ned during September for treatment. It should be taken in consid- and October. Also, no catches were recorded ering that program of medfl y control by SIT after fi rst decade of December. It seems that technique could be feasible if only lower part, medfl y can create high population through from the coastal line up to the city of Opuzen the late spring and early summer, and heavily can be treated. However, the best solution is attack citrus fruits. to treat whole area as geographic isolated This speculation can be supported through system. It should be apostrophe that envi- the observation data collected in Neretva riv- ronment pollution aspect except only friend- er valley. The lower part, planted mostly with ly area wide methods such as SIT technique mandarin monoculture was observed and and other environmental friendly supportive low medfl y population was recorded. Also techniques.

Book Fruit Flies.indb 258 28/10/2008 08:27:58 259 From Basic to Applied Knowledge Since Neretva river valley is devided between Craotia and Bosnia and Herzegovina, regional program of medfly control by useing SIT should give the best control results.

The feasibility study of medfly suppression strategies. 6th International Symposium of Fruit Flies by means of sterile males released program is of Economic Significance, Stellenbosch, S.Africa. undergoing. Some information data however 2002. Bjeliš M. and Pelicarić V. 2003: Voćne muhe – Strate- need to be observed. gija i suzbijanje. Glasilo biljne zaštite 1.2003. 47 th Implementing of the SIT technique will Croatian Plant Protection Society Annual Meeting specialy benefits the Croatian County of Brnetić, D., Prilog poznavanju atraktivnog djelovanja the Dubrovačko neretvanska županija and nekih suhih mamaca na mediteransku voćnu BiH County of Hercegovačko neretvanska muhu, Agrohemija, 5-6. 1968 Kovačević, Ž., Voćna mušica Ceratitis capitata Wied. županija, together with their farmers, stake- kao ekološki problem, Separat iz časopisa holders and local communities. “Agronomski glasnik” 1960. Markovčić, M., Identification of the relationship between hydrological dynamics and biodiversity values of Neretva River Delta, Workshop: Identify- 5. Acknowledgments ing priority activities for protection of the Neretva Delta, Mostar, Sept. 3-5, 2001. This research is financially initiated and sup- Pelicarić V. and Bjeliš M., Rezultati detekcije i monito- ported by Ministry of Agriculture and Foresty ringa sredozemne voćne muhe Ceratitis capitata of republic of Croatia and IAEA TC Project CRO Wied. ( Diptera, Tephritidae) u 2001. godini. Glasilo biljne zaštite 1.2002. 46 th Croatian Plant Protecti- 2006001. on Society Annual Meeting Rucner, D., O životu ptica u dolini Neretve, Ogranak Matice Hrvatske, Metković1993. 6.References Šimunić, I., Uporedna ispitivanja privlačnih sredstava za voćnu muhu, Zaštita bilja, 62. 1960. Beograd. Bjeliš, M. i V.Pelicarić, Fruit fly pests in Croatia; an over- Curić, Z., Donjoneretvanski kraj, Hrvatsko geografsko view of economic importance and current control društvo, Zagreb 1994.

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