Breeding for Native Genetic Resistance to Fall Armyworm B.M. … · FAW resistance identified in Caribbean maize germplasm (Wiseman et al., 1967), and moderate levels of resistance

Breeding for Native Genetic Resistance to Fall Armyworm

B.M. PrasannaDirector, Global Maize Program, CIMMYT

& & CGIAR Research Program MAIZEEmail: [email protected]

Hohenheim; Sept 11, 2018

Source: Mihm, J.A. 1985. Insect Science and its Application 6: 369-377.

European corn borerOriental corn borerPink stem borer

Sugarcane borerSpotted stem borerAfrican maize stalk borerPink stem borerAfrican armyworm

Asian corn borerAsiatic stem borerMaize stem borerAfrican armywormSpotted stem borerPink stem borer

Southwestern corn borerSugarcane borer

Fall armywormNeotropical corn borer

European corn borerFall armywormCorn ear wormRoot worm

Worldwide Distribution of Major Lepidopteran Insect-pests on Maize

ToT regional meetingCotonou, 13rd-15t Feb 2018There is no one solution that fits all!

IPM packages tailored to African agro-ecologies and smallholder context

Biological Control Biopesticides

Maize variety with at least partial resistance to FAW

++ + Agro-ecological Management

CIMMYT’s Breeding Program for Native Genetic Resistance to Insect-pests is nearly five decades old… CIMMYT’s breeding efforts

against major insect-pests in the tropics, including Fall Armyworm, initiated in the 1970s.

Insect-resistant maize populations developed using diverse sources of resistance to various borer species and Fall Armyworm.

Insect mass-rearing and germplasm screening methodologies optimized.

Work further intensified in Mexico and Africa...CIMMYT-Mexico: An array of populations (MBR; MIRT) as well as elite inbred lines with native genetic resistance to FAW derived, mainly from the Caribbean and Tuxpeno maize germplasm.

CIMMYT-Africa: Insect-resistant maize lines, hybrids and OPVs developed and released under IRMA (Insect Resistant Maize for Africa) Project

“We concentrate on attempting to identify and use more stable resistance to larval feeding: of the antibiosis, strong non-preference, or plant tolerance mechanisms (in order of priority), and as expressed in a no-choice situation under field conditions.”

– John Mihm (1984)

CIMMYT Maize Germplasm Base for Native Genetic Resistance to FAW FAW resistance identified in

Caribbean maize germplasm (Wiseman et al., 1967), and moderate levels of resistance in Tuxpeno germplasm (Smith, 1982).

Tolerance is the primary type of resistance in the Tuxpeno materials, and antibiosis and/or non-preference in the Caribbean germplasm (Smith, 1982).

Resistance in both cases is polygenically controlled and variation found to be primarily additive (Widstrom et al., 1972; Williams et al., 1978; Smith 1982).

Sources of native genetic resistance to FAW

Germplasm Sources

CIMMYT-derived insect-resistant maize germplasm:• MBR; MIRT; Pop. 304; Pop. 392; Pop. FAW-

CGA; Pop. FAW-Tuxpeno; Pop. FAW-Non-Tuxpeno

• CMLs/hybrids/OPVs based on insect-resistant maize germplasm, etc.

USDA-Mississippi temperate maize inbreds: Mp496; Mp701-Mp708, Mp713; Mp714; Mp716

Embrapa-Brazil maize germplasm: CMS14C; CMS23 (Antigua x RepublicaDominica); CMS24; MIRT (Multiple Insect Resistance Tropical) race Zapalote Chico, Sintetico Spodoptera, Caatingueiro Spodoptera, and Assum Preto Spodoptera

Facility at Kiboko, Kenya, for screening maize germplasm against FAW under artificial infestation

Similar facility will be established shortly in CIMMYT-Harare, for screening germplasm suitable for southern African agro-ecologies

FAW insect mass-rearing in KALRO-Katumani for maize germplasm screening at Kiboko

Since Feb 2018, generated and used >250,000 neonate larvae for germplasm screening; 40,000 neonates per net-house

Screening in 6 net-houses at present; screening capacity being expanded to 14 net-houses (300 entries per net-house) in Kiboko, and 8 net-houses in Harare.

Source: Prasanna et al. (2018) FAW IPM Manual

FAW Foliar and Ear Damage Ratings (1-9 Scale)

Source: Prasanna et al. (2018) FAW IPM Manual

CML444

Several elite CIMMYT-derived drought-tolerant lines are highly susceptible to FAW attack. Need for rapid conversion of the FAW-susceptible lines into resistant versions..

S.No.

Variety Type Trait Nominating Center

Release Year

Ecology

1 KATOPV OPV Stem Borer Resistant KARI Katumani 2006 Katumani (early)2 KATOPV OPV Stem Borer Resistant KARI Katumani 2006 Katumani (early)3 KATEH2006-1 Hybrid Stem Borer Resistant KARI Katumani 2007 Katumani (early)4 KATEH2006-2 Hybrid Stem Borer Resistant KARI Katumani 2007 Katumani (early)5 KATEH2006-3 Hybrid Stem Borer Resistant KARI Katumani 2007 Katumani (early)6 EMB 215 Hybrid Stem Borer Resistant KARI Embu 2007 Mid-altitude7 KM 0403 OPV Stem Borer Resistant KARI Kakamega 2007 Mid-late8 KM 0404 Hybrid Stem Borer Resistant KARI Kakamega 2007 Mid-late9 KM 0406 Hybrid Stem Borer Resistant KARI Kakamega 2007 Mid-late

10 MTPEH 0701 Hybrid LGB Resistant KARI Mtwapa 2010 Coast (Lowland)11 MTPEH 0702 Hybrid LGB Resistant KARI Mtwapa 2010 Coast (Lowland)12 MTPEH 0703 Hybrid Stem Borer Resistant KARI Mtwapa 2011 Coast (Lowland)13 KATEH 2007-3 Hybrid Stem Borer Resistant KARI Katumani 2010 Katumani (early)14 EMB 0701 Hybrid LGB Resistant KARI Embu 2010 Embu (medium)15 EMB 0703 Hybrid Stem Borer Resistant KARI Embu 2010 Embu (medium)16 SBRH-1 Hybrid Stem Borer Resistant EIAR 2015 Mid-altitude17 SPHR-1 Hybrid LGB Resistant EIAR 2015 Mid-altitude

CIMMYT-derived Insect-pest Resistant Maize Varieties released in Kenya and Ethiopia

Source: IRMA Project

CIMMYT-derived Insect-pest Resistant Maize Varieties released in Uganda, Tanzania and Malawi

Source: IRMA Project

S.No. Hybrids Country

1 CKIR12035 Uganda

2 CKIR07013 Uganda

3 CKIR12038 Uganda

4 CKIR12021 Uganda

5 CKIR12033 Uganda

6 CKIR12006 Uganda

7 CKIR12022 Uganda

8 CKIR12013 Uganda

S.No. Hybrids Country

1 CKIR12011 Tanzania

2 CKIR12012 Tanzania

3 CKIR12017 Tanzania

4 CKIR12030 Tanzania

5 CKIR12042 Tanzania

6 CKIR12030 Tanzania

7 CKPH12001 Tanzania

8 CKPH12005 Tanzania

9 CKPH12017 Tanzania

10 CKPH12031 Tanzania

11 CKPH12039 Tanzania

S.No. Hybrids Country

1 CKIR7003 Malawi

2 CKIR7004 Malawi

3 CKIR7005 Malawi

4 CKIR7008 Malawi

5 CKIR7017 Malawi

6 CKPH8002 Malawi

7 CKPH8012 Malawi

8 CKPH8041 Malawi

S.No. Hybrids Country

1 CKIR07004 Zambia

2 CKIR07012 Zambia

3 CKIR07013 Zambia

4 CKPH08043 Zambia

Screening of CIMMYT maize inbred lines under natural FAW infestation in Kakamega, Kenya

Susceptible SusceptibleResistant Resistant

Susceptible (CML444) SusceptibleResistant Resistant

CML71 CKSBL10025

Screening under FAW artificial infestation in Kiboko (Kenya) Facility

Some promising CIMMYT maize inbreds validated by USDA-Mississippi teamS.No. Inbred

1 CML702 CML713 CML4534 CML4045 CML156 CML1227 CML484

Note: Leaf damage ratings between 2.0 and 6.0, and ear damage ratings below 3.0; Susc. check ratings 8.0 or above.

S. No. Inbred8 CML679 CML332

10 CML43211 CML33312 CML33813 CML32214 CML286

Some promising CIMMYT maize inbreds identified and validated in Kiboko, KenyaS. No. Inbred

1 CML702 CML713 CML3334 CKSBL100275 CKSBL100086 CKSBL100027 CKSBL100258 CKSBL100609 CKSBL10039

10 MBR C6 Bc F234-1

Note: Leaf damage ratings between 2.0 and 6.0, and ear damage ratings below 3.0; Susc. check ratings 7.0 or above.

Some of the promising first-generation CIMMYT maize hybrids with FAW tolerance under artificial infestation in KibokoS.No Entry Foliar damage1 CKIR06007 5.53 ± 0.022 CKIR06001 5.88 ± 0.023 CKDHL164288/CLRCY039 5.88 ± 0.02R Check Mp714/Mp716 4.94 ± 0.02R Check Mp708/Mp713 5.27 ± 0.02S Check Commercial Variety 8.45 ± 0.02S Check Commercial Variety 7.88 ± 0.02

Note: Ear damage ratings of the identified resistant entries was less than 2.20 ±0.02

Almost all commercial maize varieties in Africa

Conventional / Native genetic resistance

(polygenic; low selection pressure on

the insect)

Bt maize(single

gene; high selection pressure

on insect)

Resistant Partially Resistant Susceptible Highly Susceptible

Native genetic resistance to FAW, even if partial, is important for multiple reasons..

What is the basis for conventional resistance to FAW?

• Mp708 and FAW7050 (resistant): elevated defensive proteins following insect herbivory (greater conversion of photosynthates to defensive proteins); higher amino acid and glucose contents; constitutive accumulation of jasmonic acid.

• Susceptibility of Ab24E to S. frugiperda was due to a high P/C ratio (protein-to-total non-structural carbohydrates) and a low level of induced defensive compounds.

(E)-β-caryophyllene, a terpenoid associated with resistance, is released constitutively in Mp708.

FAW-fed samples of both Mp708 (resistant) and Tx601 (susceptible) showed high transcript number of tps23, the gene responsible for the synthesis of (E)-β-caryophyllene.

FAW larvae show a preference for Tx601 whorl tissue over Mp708 tissue; dosage of Tx601 whorl with (E)-β-caryophyllene repels the FAW!

In Conclusion…• We need to effectively utilize and quantify the benefits of host

plant resistance in the IPM strategies for FAW management in African agro-ecologies and cropping system landscapes.

• Key Next Steps: – Scaling-up and deploying “first-generation FAW-tolerant maize

varieties” (those already released in ESA under IRMA) as an immediate relief to the farming communities

– Accelerated breeding for improved Africa-adapted varieties with FAW resistance and other farmer-preferred traits.

– Varietal release and deployment of “second-generation FAW-tolerant maize hybrids/OPVs in SSA

– Systematic analysis of compatibility and possible synergies between host plant resistance with other IPM approaches (e.g., biological control) with regard to FAW in Africa.

Thanks!

The CGIAR Research Program MAIZE receives W1&W2 support from the Governments of Australia, Belgium, Canada, China, France, India, Japan, Korea, Mexico, Netherlands, New Zealand, Norway, Sweden, Switzerland, U.K., U.S., and the World Bank.

The CIMMYT work on FAW in Africa presented here is funded by the USAID-FAW Project & the CGIAR Research Program MAIZE.