Source document: https://docs-lawep.s3.us-east-2.amazonaws.com/1696578534320.pdf (Zimbabwe)
P a g e | 1 DEPARTMENT OF RESEARCH AND SPECIALIST SERVICES PLANT PROTECTION RESEARCH INSTITUTE Harare Agricultural Research Centre 5th Street Extension, P. O.

Box CY 550, Causeway, Harare Phone: +263 4 700339 zpqs@iwayafrica.co.zw Fall Armyworm (Spodoptera Frugiperda) Rearing The first outbreak reports of fall armyworm in Zimbabwe were in September 2016.
The Plant Protection Research Institute (PPRI) in the Department of Research and Specialist Services has since done some rearing experiments of the pest in order to understand its life cycle under the Zimbabwean environment.

The latter was a precursor to the planned chemical efficacy experiments for the purpose of facilitating their registration for use on fall armyworm in the country, as well as to determine effective dosages that could be used farmers with minimal adverse effects on the environment.
Samples of larvae and eggs were collected from fields for rearing under room condition.

Young maize plants were used as natural diet for the developing larvae.

The adults were provided with water and honey on soaked cotton wool.

The adult moth is greyish in colour.

The forewings of the male are a mottled greyish colour with white markings near the wing tips.

The forewings of the female are similar, but the markings are less distinct (Fig 1 (a) and (b)).
Fig 1 (a): Fall Armyworm adult female Fig 1 (b) Fall Armyworm adult male The female takes about 7-17 days after emergence from the pupal stage for it to lay eggs.

Note that information on egg laying period and adult lifespan in our environment, is still under observation.

Egg Laying Eggs are laid at night on the leaves, stuck on either or both surfaces of leaves in tight clusters (Fig.

2 (a) and (b).

P a g e | 2 Fig 2 (a): Fall Armyworm eggs in a tight cluster just after being laid.
Fig 2 (b): The eggs a few days after being laid.

Fig 2 (c): Hatching of eggs, showing hatchlings.

Hatching of eggs takes about 2-5 days (Fig 2 (c)).

The young larvae feed on the leaves, with the first two instars feeding on the underside of the young leaves causing a characteristic skeletonizing or ‘windowing’ effect.

Before maize tasselling, the older larvae feed deep in the whorl/ maize plant funnel.

The larval development goes through six instars and takes 24-31 days (Fig.

3 (a)).
3 (a)).

Pupation takes place inside a loose cocoon in soil or between the leaves or cob of the host plant.

The pupal stage takes 9-13 days (Fig.

3 (b)).

Adults then emerge from the pupa at night.

“Windowing” of leaf Fig.

3 (a): Larval Stage of fall armyworm.

Fig.

3 (b): Pupal stage of fall armyworm.


P a g e | 3 Egg stage 2-5 days Fall Armyworm Development Cycle Observed Pupa stage 9-13 days Adult moth 7-17 days (Pre-oviposition period) Life cycle under room conditions (42-66 days of development) Larva stage 24-31 days Chemicals on Temporary Registration Insecticides in Table 1 have been granted temporary registration based on efficacy trial data collected in Zimbabwe.
The exception is for Belt 480SC, where Bayer applied for temporary registration using efficacy trial data from South Africa.

Table 1: Products granted temporary registration status (One year) Active Ingredient Gamma Cyhalothrin Trade Name Vantex 60CS Company Pivotal Agro Services Emamectin Benzoate Emmamectin Benzoate Polachem *Flubendiamide Belt 480 SC Bayer Additional work to screen more pesticides for use on fall armyworm in the country is planned.
During the pest outbreak in 2016/17, other chemicals used by farmers, with reasonable success included Emmamectin Benzoate with Acetamiprid (coded Blast Super P a g e | 4 by Sincrop Zimbabwe and Super Dash by TSA).

Both these are not registered in Zimbabwe or South Africa.

Verification trials will be done to collect supporting data.

Insecticides with potential to control Fall Armyworm in Zimbabwe Insecticides listed in Table 2 have been registered in South Africa for the control of fall armyworm.
In Zimbabwe, they are registered for use on other crops for control of other pests, including Spodoptera spp., with the exception of fall armyworm.

Although they have not been scientifically evaluated against the fall armyworm in the country, farmers have used some of them and obtained favourable results.

These have been logged for sequential verification work.
Table 2: Insecticides Registered for control of other pests in Zimbabwe Active Ingredient Trade Name Indoxacarb Steward 150EC Missile 150SC Companies Polachem TSA/Acol Devacarb 150SC Seed Chain Blanket 150SC Pivotal Indoxacarb 150SC Refiloe Attitude 80SC Sincrop Zimbabwe Aryna 46EC Polachem Methomyl, Lannate 90 SP and 90 WP Indoxacarb and Acetamiprid Indoxacarb and Acetamiprid Methomyl Citchem, Agricura, TSA, CP Chemicals, Adama, Curechem, Windmill, Fercochem, Cropserve, Curechem, Nova Agro, Benwik, Capital Agriculture Polachem Syngenta Bayer Ferchochem,Citchem,Windmill,Nova Agro,Agroshape,Cropserve, Capital Agriculture,ZFC,TSA,IETC, Adama Zimbabwe, Agricura, CP Chemicals, Ecomark Chlorantraniliprole Coragen 20 SC Ampligo 150ZC Chlorantraniliprole and Lambda Cyhalothrin Flubendiamide and Thiacloprid Chlorpyrifos Belt Expert Chlorpyrifos 48EC, Pyrinex 40EC, Dursban 48EC [END]