FAO Expert Meeting on Fall Armyworm Accra, Ghana (18th 20th July 2017)

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Arthur Joseph
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Armyworm Management in Africa: What do we

Expert Meeting on Fall Armyworm Accra, Ghana

1 Armyworm Management in Africa: What do we know and what can we learn? Fall armyworm (Spodoptera frugiperda) African armyworm (Spodoptera exempta) FAO Expert Meeting on Fall Armyworm Accra, Ghana (18th 20th July 2017) Professor Ken 1Wilson

2 Prof Ken Wilson Professor of Evolutionary Ecology Insects & Parasites Ecology Group Lancaster Environment Centre Lancaster University 1990 Ecology of insect crop pests Host-pathogen interactions Biocontrol of crop pests using baculoviruses Nutritional ecology of insects

3 Unanswered questions about Fall armyworms: FAO Harare meeting February 2017 Where did the Fall armyworm come from? How does its life-cycle differ from that of the African armyworm? Will it spread and will it persist long-term? How do we control it?

4 Unanswered questions about Fall armyworms Where did the Fall armyworm come from? How does its life-cycle differ from that of the African armyworm? Will it spread and will it persist long-term? How do we control it?

5 Unanswered questions about Fall armyworms Where did the Fall armyworm come from? How does its life-cycle differ from that of the African armyworm? Will it spread and will it persist long-term? How do we control it?

6 FAW: 2 strains, 4 haplotypes (Nagoshi et al.)

7 Genetic analysis of Fall armyworm from Africa Maximum likelihood condensed bootstrap barcode of Zambian larval samples using 135 bp mitochondrial cytochrome oxidase I (COI) sequence. Results from Tanzania and Rwanda being processed. Fall armyworm rice strain (RS) Fall armyworm corn strain (CS) Samples courtesy of ZARI

8 Genetic analysis of Fall armyworm from Africa: strain ID using CO1 markers Overall Togo FAW Strains (n = 62 larvae on maize, all regions, Nagoshi et al 2017) Overall Rwandan FAW Strains (>300 larvae on maize, all regions) % Rice % Corn % Rice % Corn Overall Zambian FAW Strains (n = 44 larvae on maize, all regions) Overall Tanzanian FAW Strains (n = 28 moths from trap in maize field, 1 region) % Rice % Corn % Rice % Corn

9 Genetic analysis of Fall armyworm from Africa: haplotype ID using CO1 polymorphic sites Note relatively small sample sizes Overall Zambian Corn Strain Haplotypes (n = 8 larvae) Overall Tanzanian Corn Strain Haplotypes (n = 9 moths) % h1 % h2 % h3 % h4 % h1 % h2 % h3 % h4

10 Unanswered questions about Fall armyworms Where did the Fall armyworm come from? How does its life-cycle differ from that of the African armyworm? Will it spread and will it persist long-term? How do we control it?

How will Fall and African armyworms interact? Photo: K.

Goergen Photo: Kansas State University Movement and

maize (vegetative vs reproductive parts) FAW is

11 How will Fall and African armyworms interact? Photo: K. Wilson Photo: G. Goergen Photo: Kansas State University Movement and outbreaks of both species determined by similar environmental factors Photo: K. Wilson African armyworm (Spodoptera exempta) Both eat maize (vegetative vs reproductive parts) FAW is cannibalistic (more competitive?) Both susceptible to disease do they share pathogens (enemy release vs spillover)? Fall armyworm (Spodoptera frugiperda)

12 Unanswered questions about Fall armyworms Where did the Fall armyworm come from? How does its life-cycle differ from that of the African armyworm? Will it spread and will it persist long-term? How do we control it?

13 Presumed distribution of FAW: Feb 2017 Data from Rose et al. (2000)

14 Presumed distribution of FAW: Jun 2017 Data from Rose et al. (2000)

15 Historical analysis of armyworm

16 Patterns of African armyworm outbreaks 16

uk/armyworm @spodoptera007 Fall armyworm spread movie: https://youtu.

17 Providing free accessible information on Fall and African armyworm The Armyworm Network Fall armyworm spread movie: (updates available on the Armyworm Network) 50 years of African armyworm outbreaks:

18 Early-warning system needed the power of pheromones! Courtesy of Prof Nkunika, UNZA

Rain gauge - Local operators chosen by the village -

forecaster with pheromone traps Rain gauge Mushobozi,

19 Early-warning system needed the power of pheromones! Community-based armyworm forecasting: - Pheromone trap - Rain gauge - Local operators chosen by the village - Simple rules for assessing risk of attack Community forecaster with pheromone traps Rain gauge Mushobozi, Grzywacz, Musebe, Kimani & Wilson (2005) Aspects of Applied Biology 75:

20 How do we control it? Chemicals? - Which chemicals are effective and safe? Resistance? GM crops? - Is Africa ready? Costs? Resistance? Biological pesticides?

21 Biological control Bt pesticide spray can be effective (resistance?) Botanicals (e.g. neem) can also be effective, especially for smallholder farmers who lack access to chemicals Biopesticides natural diseases of insects (viruses, fungi, bacteria, etc.)

22 Botanicals Botanicals (e.g. neem, Tephrosia vogelii, pawpaw, etc.) can also be effective, especially for resource-poor smallholder farmers who lack access to chemicals.

23 Biopesticides David Grzywacz (Natural Resources Institute, U.K.) Wilfred Mushobozi (EcoAgriConsult Ltd, Tanzania) Ken Wilson (Lancaster University, U.K.)

24 A virus-processing plant built in Tanzania ready to produce tonnes of SpexNPV biopesticide locally Funding for registration and commercialisation to end product is still needed There is a similar biopesticide (SfMNPV) that is being produced commercially against Fall armyworm in the Americas!

25 Does SpexNPV also kill African FAW? Probably not but Very preliminary results at this stage (just one replicate of each, single isolates)

26 Resistance management Baculoviruses compatible with other IPM approaches due to low impact on non-target organisms Baculoviruses tend to be genetically diverse (more targets for selection) - >100 genotypes of SpexNPV in Tanzania alone Resistance very unlikely (only one known case, swiftly resolved) Governments panic buy pesticides, so let s make sure there are safe pesticides for purchase (registration).

presence of SfMNPV virus possibly 2 strains (but needs

27 What about microbes in the wild - NPV? Preliminary analyses of Tanzanian moths suggest the presence of SfMNPV virus possibly 2 strains (but needs sequencing); lower prevalence in Zambian larvae plus other viruses may be present.

28 What about microbes in the wild - fungus?

29 What about other natural enemies? Earwig (Dermaptera) Parasitoids (incl. Campoletis sp.) Other natural enemies of AAW well described

30 Summary Fall armyworm has spread across Africa at an alarming rate, though the true impact on maize production has yet to be established We know lots more than we did even just a few months ago but there still remain many unanswered questions We can learn a lot from African armyworm experiences, as well as experiences in the native range of the FAW We now need a regional strategy for the monitoring and management of this new invasive pest.

31 LANCASTER UNIVERSITY The End

32 S. frugiperda host strain: Corn Strain (CS) EcoRV negative (GATACC), Rice Strain (RS) = EcoRV positive (GATATC)

S. frugiperda host strain: Nucleotides 1178-1183: Corn Strain (CS) EcoRV negative (GATACC), Rice Strain (RS) = EcoRV positive (GATATC)

33 S. frugiperda host strain: Nucleotides : Corn Strain (CS) EcoRV negative (GATACC), Rice Strain (RS) = EcoRV positive (GATATC) Nucleotides 1164/1287 Corn Strain Haplotype 1 = A/A Corn Strain Haplotype 2 = A/G Corn Strain Haplotype 3 = G/A Corn Strain Haplotype 4 = G/G

New approaches to improve the livelihoods of poor farmers and pastoralists through monitoring and control of African armyworm, Spodoptera exempta.

New approaches to improve the livelihoods of poor farmers and pastoralists through monitoring and control of African armyworm, Spodoptera exempta. WILFRED L MUSHOBOZI, 1 DAVID GRZYWACZ 2, RICHARD MUSEBE