IOBC/wprs Bulletin Vol. 28(2) 2005

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stands (Levine et al. 2002) to feed on flowers and pollen, e.g. on sunflower (Hatvani & Horvath 2002), or on volunteer winter wheat in harvested wheat fields. Moreover, a small proportion of 5 to 15% of the D. v. virgifera adult population was found active near the ground surface of non-maize crops probably laying eggs so that larvae develop in the subsequent maize (Komáromi et al. 2002, Kiss et al. 2004b). In conclusion, to reduce selection pressure for developing behavioural resistance, the above-mentioned critical crops should not be long-term rotated with maize over whole agricultural regions. The rotation should be kept as diverse as possible partly including fields with two successive years of maize and other fields with two successive years of non-maize. Option 2: Biological control A three-year field survey conducted in Hungary, Serbia and Croatia, aimed to determine the occurrence of indigenous natural enemies of D. v. virgifera in Europe (Toepfer & Kuhlmann 2004b). Though Toth et al. (2002) reported on the presence of spiders preying on D. v. virgifera, and FAO (2004b) is currently screening generalist predators of D. v. virgifera, it was concluded from the survey results that host-specific and/or effective indigenous natural enemies are not currently attacking any of the life stages of the alien invasive pest in Europe (Toepfer & Kuhlmann 2004b). Classical biological control Classical biological control provides an opportunity to reconstruct the natural enemy complex of an invading alien pest and its application to manage D. v. virgifera populations in Europe should be considered (Kuhlmann & Burgt 1998). Therefore, the natural enemy complex of Diabrotica species was surveyed in their area of origin in Central America (Kuhlmann et. al. 2004) and Celatoria compressa (Diptera: Tachinidae) was the only parasitoid found on the target species, D. v. virgifera. Its host range is considered to be restricted to Diabroticite beetles, and thus Celatoria compressa would be safe for introduction because direct and indirect impacts on other organisms would be extremely low (Kuhlmann et al. 2004). Classical biological control is considered as only one element within an IPM strategy that is compatible and applicable with other control measures. Inundative biological control using entomopathogenic nematodes (EPN) EPNs are known to have great potential as biological control agents of insects (Poinar 1979, Gaugler 2002) and are successfully applied in horticultural and green house pest control. In contrast, the application of EPN at field scale against field pests is still an innovative field of research. EPN species commercially available in Europe have been screened for their efficacy against both the root-feeding larvae and silk-feeding adults of D. v. virgifera in laboratory. Findings suggest the development of a biocontrol product with EPNs against the pest larvae (Rasmann & Turlings 2004) Inundative biological control using entomopathogenic fungi (EPF) More than 750 fungi species infect insects and mites. Many EPF are known as important natural regulators of pest populations, however, Diabrotica-populations in the United States are usually not regulated by fungi (Maddox & Kinney 1989). Also, in Hungary, the fungi Beauveria bassiana (Bals.) Vuill. (Mitosporic fungi; formerly Deuteromyces) and Metarhizium anisopliae (Metsch.) Sorok (Mitosporic fungi) naturally attack adults of D. virgifera only at a low level < 1% (Toepfer & Kuhlmann 2004b). However, in laboratory bioassays, M. anisopliae (isolated from Melolontha melolontha by E. Dormannsné, Plant Health Service, Hodmezovasarhely, Hungary) appeared to be highly effective in killing 3
4 second and third instar larvae of D. v. virgifera. Within 14 days, 96% ±5.1 SD of the D. virgifera larvae died after indirect infestation with spores (Petri-dishes with one larva, a maize seedling, and with M. anisopliae spores sprayed on filter paper). This was significantly more than the 44% ± <strong>28</strong> SD natural mortality in larvae in the control dishes (P< 0.005, Nonparametric Chi Square Test, n = 26). Consequently the fungi increased mortality in larvae by about 52%. About 18% ± 2.3 SD) adult D. virgifera emerged from the third instar larvae when the soil with maize plants had been infested with M. anisopliae spores in laboratory (34 soil trays of 190 x 120 x 45 cm with maize roots, sprayed with 3 x 10 6 spores per cm 2 ; 4 to 5 days after maize germination each tray infested with 6 second or third instar larvae; 38 days experiment in green house, natural light, 23 to 27 °C). In the control, about 38% ± 38 SD adults emerged from larvae when the soil had not been infested with fungi (difference not significant due to high variation in emergence data, P = 0.068, Nonparametric Mann Whitney Test, Z = - 1.8). These promising results, based on the fact that M. anisopliae is widely distributed in arable land (Keller et al. 2003), and that products based on this fungus are registered in several countries (Inglis et al. 2001), suggest further research towards the development of a fungal biocontrol product. Option 3: Host plant tolerance and host plant resistance A host plant tolerance strategy against D. v. virgifera is an option for IPM in maize. Although no current commercial and non-GM maize hybrids suppress larval populations, hybrids with an extensive root system and an abundant development of secondary roots, as well as a tolerance to drought stress, can compensate for the effect of larval feeding (list of Genotypes in Baca et al. 1995; Croatian hybrids in Ivezic et al. 2001). Genetically modified maize varieties with Bt toxin expressed in its roots, (Cry3Bb1, Cry34Ab1, Cry135Ab1; Pershing 2001, Monsanto 2003) can prevent larval damage. The transgenic maize MON 863 (Cry3Bb1) is currently under review for import in the EU (J. Romeis, pers. comm. 2004). The European Food Safety Agency has recently recommended allowing the Bt-maize to enter the EC market (EFSA 2004). These developments make it likely that MON 863 maize will become available as a tool for D. v. virgifera control in Europe. However, prior to considering the use of GM maize as an IPM strategy, precautionary risk assessments are necessary (Boller et al. 1997). Bt-transgenic maize could affect biological control agents or other non-targets either directly through the Bt-toxin or indirectly due to an altered nutritional quality of the prey or host species (Dutton et al. 2003, Al-Deeb & Wilde 2003). Option 4: Selective chemical control The last step in an IPM strategy is the possibility of using direct control measures during pest outbreaks. One may apply foliar 'contact kill' insecticides against adults to reduce silk feeding damage and/or reduce egg laying. For this purpose, broad-spectrum pyrethroids and organophosphates are generally used. However, several cases of resistance to insecticides are already known for D. v. virgifera, such as regionally developed resistances to organophosphates, e.g. methyl parathion, or to carbamate insecticides, e.g. carbaryl. Moreover their honeybee toxicity, their re-entry interval, and application difficulties due to maize height are limiting factors for application. These insecticides also endanger the biological control of the European corn borer, Ostrinia nubilalis, with Trichogramma parasitoids (R. Burger, pers. comm. 2004). A recently (2003) registered management option in Hungary is the ‘attract and kill’ method, where a small amount of insecticide (usually 10% of the registered amount) is combined with natural feeding stimulants/arrestants or attractants, e.g. cucurbitacins (INVITE EC). A seed treatment with the systemic clothianidin (neonicotinoid) reduces D. v. virgifera larval density as well as other root feeding pests (Altmann & Springer 2003).
Page 1 and 2: IOBC / WPRS Working group „Insect
Page 3: Preface The Working Group “Integr
Page 6 and 7: iv ERICSSON Jerry University of Bri
Page 8 and 9: vi PÁZMÁNDI Christian Centre for
Page 10 and 11: viii
Page 12 and 13: x Metarhizium anisopliae for white
Page 14 and 15: xii
Page 16 and 17: Insect Pathogens and Insect Parasit
Page 20 and 21: In conclusion, the chemical control
Page 22: Kuhlmann, U. & W.A.C.M. Burgt 1998:
Page 25 and 26: 10 Austria, Belgium, Czech Republic
Page 27 and 28: 12 The control strategies used agai
Page 29 and 30: 14 1) Case study: Soil application
Page 31 and 32: 16 2) Case study: Genetic diversity
Page 33 and 34: 18 Bidochka, M.J., Menzies, F.V. &
Page 38 and 39: Results and discussion The first co
Page 40 and 41: Isolation of Beauveria brongniartii
Page 42 and 43: grown in the dark for 3 weeks at 22
Page 44: genotypes (A, B, D, and F) were re-
Page 47 and 48: 32 Since 1974 the financial losses
Page 49 and 50: 34 there is no more a strict three
Page 54 and 55: Numbers of captured beetles were an
Page 56 and 57: Mean captues +/- SE per trap & day
Page 58 and 59: dilution for plating (see above). F
Page 60: 45 “New” white grubs
Page 63 and 64: 48 The goal of this study was to de
Page 65 and 66: 50 In spring 2003 the density of M.
Page 67 and 68: 52 (Germany). The first treatment w
Page 69 and 70:
54 Application timing of H. bacteri
Page 72 and 73:
Insect Pathogens and Insect Parasit
Page 74 and 75:
Results and discussion Collection o
Page 76:
Discussion During this study the en
Page 79 and 80:
64 Materials and methods Source of
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66 100 80 60 40 20 0 100 80 60 40 2
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68 During this study, selectivity a
Page 86:
71 Wireworms
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74 Solanum tuberosum L. (Solanaceae
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76 % CATEGORIZATION OF MORBIDITY FI
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78 of adults caught can reliably pr
Page 96 and 97:
Page 98 and 99:
Results and discussion Before spray
Page 100:
References Parker, W.E. & Howard, J
Page 103 and 104:
88 insecticide residues. Nonetheles
Page 105 and 106:
90 References Cockbill, G.F., Hende
Page 107 and 108:
92 Results and discussion a. Taxono
Page 109 and 110:
94 published; some information has
Page 111 and 112:
96 C2a: no sensitive crops in the s
Page 113 and 114:
98 Furlan, L., Tóth, M., Ujvary, I
Page 115 and 116:
100 Roberts, A.W.R. 1928: On the li
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102 Results and discussion Crop rot
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104 % damage by wireworms 100 80 60
Page 121 and 122:
106 noticed that grass-clover in cr
Page 123 and 124:
108 % damage by wireworms 60 50 40
Page 125 and 126:
110 Materials and methods Soil Soil
Page 127 and 128:
112 Emigration - deterrence of wire
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114 Table 1. The effect of broadcas
Page 131 and 132:
116
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118 presence and abundance of wirew
Page 135 and 136:
120 Furthermore, A. obscurus larvae
Page 137 and 138:
122 Horton, D.R. & Landolt, P.J. 20
Page 139 and 140:
124 Bait trapping 48 bait traps wer
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126 Acknowledgements We thank Anton
Page 143 and 144:
128 history can be obtained (Scheu
Page 145 and 146:
130 lower left hand corner of fig.
Page 147 and 148:
132 Eggers, T. & Jones, T.H. 2000:
Page 149 and 150:
134 pheromone combinations for each
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136 Fig. 2. Click beetle spp. captu
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138 Fig 4. Click beetle spp. captur
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140 Fig 6. Click beetle spp. captur
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142 Siirde, K., Lääts, K., Erm, A
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Fig. 2. Comparison of several trap
Page 166 and 167:
Fig. 5. Catches of WCR in VARs+ tra
Page 168 and 169:
Table 1. Performance characteristic
Page 170:
Miscellaneous
Page 173 and 174:
158 Material and methods Field tria
Page 175 and 176:
160 Figure 2: Abundances of Collemb
Page 177 and 178:
162
Page 179 and 180:
164 but also when used against the
Page 181 and 182:
166 based EPN product in this exper
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168
Page 185 and 186:
170 branches. Beetles can walk up t
Page 187 and 188:
172 1999/ 2000, I 1999/ 2000, C 200
Page 189 and 190:
174
Page 191 and 192:
176 Experimental design During the
Page 193 and 194:
178 Acknowledgements We thank Stefa
Page 195 and 196:
180 Spore suspension Conidia of M.
Page 197 and 198:
182 Data about the stability of spo
Page 199 and 200:
184 dence of host presence and appl
Page 201 and 202:
186 Material and methods All habita
Page 203 and 204:
188 Hajek, A.E. & Leger, R. J. St.
Page 205 and 206:
190 Risk Assessment of Fungal Biolo
Page 207:
192 It is scheduled that our future
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IOBC/wprs Bulletin Vol. 28(2) 2005

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