Harnessing biodiversity for sustainable pest management
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Harnessing biodiversity for sustainable pest management

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Ecology and Biodiversity studies,Strategy for deploying biocontrol agents,IPM approach for flower thrips,Developing alternatives to cotton pesticides in Benin

Ecology and Biodiversity studies,Strategy for deploying biocontrol agents,IPM approach for flower thrips,Developing alternatives to cotton pesticides in Benin

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Harnessing biodiversity for sustainable pest management Harnessing biodiversity for sustainable pest management Presentation Transcript

  • Harnessing biodiversityfor sustainable pest management Manuele Tamò insect ecologist Contract Review Seminar, October 13, 2009 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Cowpea, Vigna unguiculata Walpers Major source of proteins for balanced diet with starchy staples Dual purpose: food-feedBut: substantial losses dueto pests and diseases International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Strategic vision for cowpea IPM (5-10 years)Preventive side:• Host plant resistance (incl. transgenics)• Conservation biological controlCurative side:• Inoculative and augmentative biological control• Bio-pesticides• Synthetic insecticides International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • The legume pod borer, Maruca vitrata International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Ecology studies Major alternative host plants in moist savannas of West AfricaPterocarpus santalinoides Lonchocarpus cyanescens Lonchocarpus sericeus Tephrosia candida International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Abundance of larvae of M. vitrata on selected host plants in Southern Benin L. sericeus 60 P. santalinoides 50 T. platycarpa 40 30Larvae of M. vitrata 20 10 0 Oct Dec Feb Apr Jun Aug Oct International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • cumulative eggs/larvae per plant Mean cumulative catch per site 28 28 -A -A 0 10 20 30 40 50 60 70 0 5 10 15 20 25 pr pr 5- 5- M M ay ay 12 12 -M -M ay ay 19 19 -M -M ay ay 26 26 -M -M ay ay 2- 2- Ju Ju n n 9- 9- Ju Ju n n 16 16 -J -J u n u n 23 23 -J -J u n u n 30 30 -J u n -J u n 7- 7- Ju l Ju l Within Pods 14 Males -J 14 u Within Flowers -J l u Females l 21 -J 21 u l -J u l 28 -J 28 u l -J u l Pheromone traps as monitoring toolsInternational Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Population „migration‟ of M. vitrata based on availabledata from light traps and host plant surveys: implicationfor control strategies International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Biodiversity studies Natural enemies of Maruca vitrata in West Africa 1 mmEgg parasitoidsTrichogrammatoidea eldanae International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Natural enemies of Maruca vitrata in West Africa Braunsia kriegeriPhanerotoma leucobasis International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Maruca vitrata larval parasitism rates on different host plants in Benin 50 Phanerotoma leucobasis 40 Braunsia kriegeri 30 20 10 0 Lc Ls Ps Pp Tp Vu Lc: Lonchocarpus cyanescens Pp: Pueraria phaseoloides Ls: Lonchocarpus sericeus Tp: Tephrosia plathycarpa Ps: Pterocarpus santalinoides Vu: Vigna unguiculata (cowpea) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • What‟s the origin of M. vitrata and why do we bother?Source: CABI Crop Protection Compendium International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Biodiversity studies at AVRDC, TaiwanApanteles taragamae Dolichogenidea sp. Triclistus sp. Trichomma sp. International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Apanteles taragamae Viereck (Hymenoptera, Braconidae)Biological and ecological studies 12 0.7 10 0.6 0.5 8 0.4mx lx 6 0.3 4 0.2 2 0.1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 days International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Experimental releases …but no direct evidence of establishment yet International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Biodiversity ofentomopathogenicorganismsSeveral fungal pathogensidentified, none of practicalinterestIncidence of infection of M.vitrata cypovirus (MvCPV) from<10% to 100% (6% severelyinfected) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • A serial killer: Maruca vitrata NuclearPolyhedrosis Virus (MaviMNPV) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • MaviNPV: lab studies at AVRDC 120 a 100 a a a 80 aMortality (%) 60 b b b ab b b b b bc 40 a bc a aa a b abab ab 20 aa a a c a b a c c a 0 1 2 3 4 5 6 Days after treatment Check 100 PIBs/ml 500 PIBs/ml 1000 PIBs/ml 2500 PIBs/ml 5000 PIBs/ml International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • MaviNPV: lab studies at IITA with Benin populations of M. vitrata 100% Control 2.053x10º 80% 2.053x10¹ 2.053x10²mortality 60% 2.053x10³ 2.053x104 40% 2.053x10^5 20% 0% 0 1 2 3 4 5 6 7 days after application International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • MaviNPV: caged field studies at IITA-Benin treatement % mortality (OB/ha) 0.1000 9,12 c 2.1009 24,43 bc 2.1010 35,55 bc 2.1011 56,25 ab 2.1012 75,00 a 2.1013 87,92 a International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • A. taragamae and MaviMNPV flying together ! + = !!!!! International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Presence of MaviMNPV OB in larvae of Maruca vitrata as afunction of different contamination methods using 2h and 24h virusexposure time. Exposure time Treatmentstr 2h 24 h Control 0b 0b Ovipositor 0,91 a 0,96 a Whole body 0,94 a 0,97 a Diet 0,90 a 0,98 a P>F <0,0001*** <0,0001***Another important discovery: at temperatures <25 C co-infectedlarvae will be killed by the virus before parasitoids can form a cocoon International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Strategy for deploying biocontrol agents:Exotic parasitoids:• overall reduction of the population pressure,particularly on wild host plants during the off-seasonMvNPV:• to be used like a biopesticide for inundativebiological control e.g. once pheromone derivedthreshold is reached International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Insect resistant cowpea – conventional breeding • no reliable sources of resistance in crossable species • wide crosses unsuccessful • use of susceptible varieties possible with chemical control 2 spray No spray Variety Grain Fodder Grain Fodder (kg/ha) (kg/ha) (kg/ha) (kg/ha) IT90K-277-2 2697 2219 549 3236 IT95K-231-1 2235 2619 312 3043 IT95K-193-12 2020 1513 496 1462 Dan lla (Local) 1407 3050 14 3677 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Table 2 Performance of cowpea Breeding Lines in Ibadan During the Second Season (September to November) of 1998______________________________________________________ Spray No Spray _______________________Cowpea Line Total seed Good seed Total seed Good seed IP yield (kg/ha) yield (kg/ha) yield (kg/ha) yield(kg/ha)___________________________________________________________IT95M-268-1-4 1530.7 1377.4 1479.5 1350.8 2IT95M-305-1 1479.5 1313.6 1328.6 1190.2 2IT95M-190-4 1539.1 1348.2 1303.2 1123.6 2IT95M-7 1567.0 1520.7 1256.1 1192.7 3IT95M-190-1 1349.0 1233.6 1192.7 980.2 2IT95M-309-1 1490.3 1450.3 1177.3 1091.5 2IT95M-249-1 1502.8 1425.7 1127.7 935.6 2TVU14476 (CK) 1207.3 1120.2 994.8 915.6 3IT86D-715 (CK) 1034.4 876.8 673.1 574.3 2IT86D-719 (CK) 1012.3 821.4 614.3 457.6 2LSD 5% 310.4 303.3 380.8 355.2CV % 16.1 17.1 24.1 25.1 1__________________________________________________________*IPE = Pod evaluation index International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • The Bt-protein is found in most green organs of transgenic cowpea 1 2 3 4 5 6 7 8 9 75 Kd 50 Kd * Cry 1Ab 37 Kd Pet YL OL SEP PET Poll Pod Imm Mat Seed SeedCourtesy: T.J. Higgins, CSIRO *LSU International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Bt-mediated effect on M. vitrata parasitoids - using different doses of Cry1Ab toxin on Phanerotoma leucobasis- Parasitoid egg inserted in M.vitrata egg, but development ofparasitoid larva only in late 1-stinstar- substantial mortality of developingparasitoids only when exposed toLD95 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Prospective NTO studies on M. vitrata natural enemiesOther parasitoids to be studied:-Trichogrammatoidea eldanae (egg, local)- Braunsia kriegeri (larva, local)- Pristomerus sp. (larva, local)- Bracon sp. (larva, local)- Dolichogenidea sp. (larva, local)- Testudobracon sp. (larva, local)- Apanteles taragamae (larva, exotic)- Bassus aper (larva, exotic)- Nemorilla maculosa (larva, exotic) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Prospective NTO studies on other LepidopteraOther Leps encountered on cowpea:Arctiidae Amsacta sp.Gracillaridae Acrocercops sp.Lycanidae Euchrisops malathana Virachola antalusLymantriidae Euproctis innonataNoctuidae Agrotis ipsilon Helicoverpa armigera Spodoptera littoralis Trichoplusia limbirenaOlethreuthidae Cydia ptychoraPyralidae Elasmopalpus lignosellus Etiella zinckenella Sylepta derogata International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • „IPM model‟ for Maruca vitrataNovel BC agents MR-cowpea Biopesticides as tools in IRMAlternative hostplans (BC and IRM) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Looking ahead:Another potential biocontrol candidate from Taiwan:Nemorilla maculosa (Diptera, Tachinidae) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • A parasitoid which also attacks a recalcitrant polyphagous pest:Helicoverpa armigera International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • New BMZ project: large biodiversity of M. vitratanatural enemies in Asia and maybe in South America International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Pulses-CRSP project: M. vitrata rearing for nationalprograms and farmer groups International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • What is this mess???International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Rearing methodology with germinating cowpea grains is 25-30x lessexpensive than standard artificial diet for the same larval output level !!! International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • The bean flower thrips, Megalurothrips sjostedti Trybom (Thys., Thripidae) Photo: G. Goergen International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Biodiversity studies: natural enemies of M. sjostedti Larval parasitoid: Ceranisus menes Walker Predator: Orius albidipennis Reuter 0.5 mmEgg parasitoid: Megaphragma sp. International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Parasitism rates of M. sjostedti larvae by C. menes on selected host plants V. unguiculata 31754P. santalinoides 7590 L. sericeus 8357 L. cyanescens 5671 T. candida 8222 0 1 2 3 4 5 % International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Origin and distribution Megalurothrips sjostedti Megalurothrips usitatus International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Discovery of the thrips parasitoid Ceranisus femoratus in CameroonImportant parasitism rates on wild host plants V. unguiculata 5841 C. pubescens 130 2315 T. candida D. guineensis 1110 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Dioclea guineensisInternational Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Laboratory rearing very labour intensive and expensive 2 mm International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • In-field mass rearing on Tephrosia candida International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Megalurothrips sjostedtiEstablishment of the exotic thrips parasitoid Ceranisusfemoratus 3 years after the initial releases in threecountries International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Large dataset from Benin, comparing multi-year data before releases and 4 years data after the releases 250 200 150 100 50 0 Lonchocarpus Lonchocarpus Pterocarpus Tephrosia Tephrosia sericeus cyanescens santalinoides bracteolata candidaAverage number of M. sjostedti larvae per inflorescence ofdifferent host plant (blue: period 1992-95, red: period2005-2007) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Ecological impact: up to 43% reduction of thrips populationon wild host plantsEconomic impact: on-going collaboration with agro-economists for developing ex-ante impact assessmentmodels International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Host plant resistanceCultivars Damage index First season Second seasonMoussa local 2.06 c 3.42 cdSewe 2.06 c 3.42 bcSanzisabinli 2.13 c 1.93 dTVu 1509 (RC) 2.38 c 3.25 cdIT90K-277-2 4.88 b 3.67 cdKVx404-8-1 4.88 b 4.67 bIT91K-180 5.06 b 5.75 aTVx 3236 5.13 b 5.17 bVita7 (SC) 7.56 a 7.59a International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Complementary biocontrol agents targeting the cowpeaplant: the predatory mite Amblysieus swirskii International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • IPM approach for flower thrips- Host plant resistance in available germplasm- Improved biological control: On wild hosts: Ceranisus femoratus On cowpea: Amblyseius swirskii- Biopesticides: entomopathogens botanical extracts International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Cowpea aphid, Aphis craccivora International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Aphid colonies destroyed by Neozygites fresenii in the Oueme valley (Benin) during „harmattan‟ conditionsInternational Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Cowpea aphid Aphis craccivoraImpact of the entomopathogenic fungus Neozygites freseniiZone aphid infection infestation rateSouth <10 96%Center >200 7%North >500 0% International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Natural enemies biodiversity studies: • „usual‟ predator complex • but no hymenopteran parasitoids until mid- 2007International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Possible new biocontrol project?Source: CABI Crop Protection Compendium International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Mumies of the parasitoid Lysiphlebus testaceipes International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • On-going and futures studies:• Interactions with entomopathogenic fungusNeozygites fresenii• Interactions with alternative host plants for thecowpea aphid• Interactions with other aphid species (e.g. Aphisgossypii)• novel natural enemies from Mid East International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Potential for using bio-pesticides against podsucking bugs Clavigralla tomentosicollis killed by the fungus Beauveria bassiana Investigation of aggregation pheromones for developing “lure and kill” approaches International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • PRONAF: Farmer participatory approach for IPMFarmer Field School model has beenmodified and adapted to local conditionswithin the cowpea agroecosystems inAfrica- combined ToT/FFS within the sameseason (saves one season)- no need for validation trials fortechnologies already developed on-farmby the various national programs (savesanother season)- ToT at country level is non-residential(cost savings) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • New technology for FFF?Solar-powered MP3 players- FFF can now be augmentedwith messages regarding theagricultural issues beingaddressed.- Such devices can be takenback to the communitieswhere the messages can beplayed repeatedly (biggestadvantage over rural radiomessages which are oftenplayed only once) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Biological control of the millet head borer Heilochaelus albipunctella (McKnight foundation)Millet head borer damage Parasitoid: Habrobracon hebetor International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Parasitoid release areasNord Villes Zone de lâcher du parasitoïde MALI NIGER Sego Zinder Niamey u Maradi Bamako Ouagadougou BURKINA FASO International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Full farmer-participatory biological control projectCountry Villages Producers keeping release bags Release bags Evaluation Number of millet installed (villages assessed) spikes observed Men Women Release villages Control villagesNiger 90 470 25 1303 24 8 14400Burkina Faso 51 235 20 690 23 5 16350Mali 31 83 10 465 31 8 17750Total 172 788 55 2458 78 21 48500 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Burkina, 2008 Larvae killed by H. hebetor 10.9 Villages lâchers villages témoins0.80.70.60.50.40.3 Larvae killed by others0.20.1 0 Seytenga Gorgadji Dori Arbinda Seytenga Gorgadji Dori Arbinda International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Prototype mass production of trichogrammatids against millet head borerTrichogrammatoidea eldanae International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Developing alternatives to cotton pesticides inBenin (Dutch Embassy in Benin) Cotton bollworm, Helicoverpa armigera International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • - biopesticides:entomopathogens, neem oil- trap plants: sunflowers,marigolds- conservation of locallyavailable natural enemies(parasitoids, spiders etc.)- integration of all theseoptions International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Milieux paysans (Banikoara)Pratiques Godou Ounet Goumonri Founougo Nombre Rendements Nombre Rendements Nombre Rendements Nombre Rendements moyen de H. moyen (kg/ha) moyen de H. moyen (kg/ha) moyen de H. moyen (kg/ha) moyen de H. moyen armigera par armigera par armigera par armigera par (kg/ha) cotonnier cotonnier cotonnier cotonnierHuile de neem 0,090 ± 0,031 a 990 ± 248 a 0,056 ± 0,033 a 460,4 ± 99 0,967 ± 0,160 a 333 - 410,4 ± 69Metarhizium 0,124 ± 0,034 a 1238 ± 35 a 0,061 ± 0,035 a 212,5 ± 6 1,000 ± 0,180 a 238 - 218,8 ± 38anisopliaeBeauveria 0,071 ± 0,051 a 998 ± 43 a 0,045 ± 0,028 a 495,8 ± 84 1,096 ± 0,191 a 340 - 379 ± 65bassianaConventionnel 0,200 ± 0,108 a 1154,2 ± 211 a 0,085 ± 0,037 a 517 ± 214 1,033 ± 0,165 a 538 - 556 ± 232 International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • IPM of cashew pests (BMZ)The (invasive?) cashew leafminer Eteoryctis syngramma (Meyrick) International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • New challenges in insect ecology Apate terebrans in action International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Thanks to all my collaboratorsAt IITAC. Agboton, B. Datinon, D. Djegui, D. Kpindou, A. Onzo, G. Goergen, O. Coulibaly,C. Fatokun, O. Boukar, M. Ayodele, L. KumarIn AfricaBenin: D. Arodokoun, INRAB; P. Atachi, FSA/UAC, A. Paraiso, UP, S. Saizonou,SPV + several NGOsBurkina Faso: C. Dabire and M. Ba, INERAGhana: H. Braimah, CRI, S. Asante, SARI; M. Kofya-Boamah, PPRDSNiger: B. Ibrahim, INRANNigeria: M. Dike, ABU; F. Pitan, UAbeokuta; N. Oigiangbe, UAkureWith other centers/advanced labsAfricaRice: F. Nwilene, A. TogolaAVRDC: R. Srinivasanicipe: N. ManianiaNRI: M. DownhamWAU: A. van Huis, M. DickeUGoettingen: S. VidalUIllinois: B. Pittendrigh, D. OnstedUPurdue: L. Murdoch International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org
  • Thanks to our sponsors • CGIAR core donors • SDC • IFAD • Gatsby Charitable Foundation • BMZ • DfID • RDA South Korea • Pulses-CRSP • AATF • McKnight Foundation…and thanks to you all for your attention ! International Institute of Tropical Agriculture – Institut international d‟agriculture tropicale – www.iita.org