MLN Tolerant/Resistant germplasm
The vast majority of current commercial maize varieties grown in East Africa are susceptible under artificial MLN inoculation. Testing in Kenya in 2013 indicated that 122 out of 124 commercial maize varieties were extremely susceptible to MLN. Extensive screening of materials at the KALRO/CIMMYT MLN screening facility at Naivasha, Kenya indicates 90% of materials screened (over 62,000 entries) are susceptible to MLN.
Intensive breeding efforts are being undertaken by CIMMYT Global Maize Program and national maize breeding programs to develop new resistant or MLN-tolerant varieties.
A total of 9 MLN-tolerant/resistant hybrids have been either released or recommended for release so far in eastern Africa (Kenya, Tanzania and Uganda), of which four are at different stages of commercial seed scale-up and commercialization
MLN-tolerant hybrids released / recommended for release / under NPTs in east Africa (as of Feb 2017).
Country |
CIMMYT-derived MLN-tolerant Hybrid |
Year of Release |
Released by |
Seed Company |
Status |
| Kenya | CKMLN150074 | 2019 | Seed Co. Ltd | Seed Co. Ltd | Recommended for release through Seed Co. Ltd |
| Kenya | WE7117 | 2018 | KALRO | KALRO | Recommended for release through KALRO |
| Kenya | WE7118 | 2018 | KALRO | KALRO | Recommended for release through KALRO |
| Kenya | WE7119 | 2018 | KALRO | KALRO | Recommended for release through KALRO |
| Kenya | WE5135 | 2017 | KALRO | Second generation MLN-tolerant hybrid recommended for release through KALRO | |
| Kenya | WE5136 | 2017 | KALRO | Second generation MLN-tolerant hybrid recommended for release through KALRO | |
| Kenya | WE5138 | 2017 | KALRO | Second generation MLN-tolerant hybrid recommended for release through KALRO | |
| Kenya | WE5139 | 2017 | KALRO | Second generation MLN-tolerant hybrid recommended for release through KALRO | |
| Kenya | WE5140 | 2017 | KALRO | Second generation MLN-tolerant hybrid recommended for release through KALRO | |
| Kenya | KATEH15-01 | 2017 | KALRO | Recommended for release through KALRO | |
| Kenya | KATEH15-02 | 2017 | KALRO | Recommended for release through KALRO | |
| Kenya | KATEH15-03 | 2017 | KALRO | Recommended for release through KALRO | |
| Kenya | WE6109 | 2016 | KALRO | Recommended for release through KALRO | |
| Kenya | WE6110 | 2016 | KALRO | Recommended for release through KALRO | |
| Kenya | H13ML | 2014 | KSC | KSC | Bulking of breeder seed in progress; commercialization possible in 2017/2018 |
| Kenya | H12ML | 2013 | KSC | KSC | Released in 2013. KSC will produce basic seed in 2016, and expect to commercialize the hybrid in 2017. Promotion of the hybrid in progress |
| Kenya | WE6111 | NPT2 | |||
| Kenya | WE6108 | NPT2 | |||
| Tanzania | WE5135 | 2019 | COSTEC | COSTEC | Recommended for release through COSTEC |
| Tanzania | WE7118 | 2019 | COSTEC | COSTEC | Recommended for release through COSTEC |
| Tanzania | WE5141 | 2019 | COSTEC | COSTEC | Recommended for release through COSTEC |
| Tanzania | WE7133 | 2019 | COSTEC | COSTEC | Recommended for release through COSTEC |
| Tanzania | Meru HB607 | 2014 | Meru-Agro | Meru-Agro | Released in 2014. The company is planning to produce basic seed in 2016 and commercialize the hybrid in 2017. Promotion on progress. |
| Tanzania | WE6108 | NPT2 | |||
| Tanzania | WE5136 | NPT2 | |||
| Tanzania | WE5139 | NPT2 | |||
| Tanzania | WE5141 | NPT2 | |||
| Uganda | Bazooka (UH5354) | 2014 | NARO | NASECO | Released in 2013, and already being commercialized. Over 20 tons of certified seed harvested by Aug 2015; Being commercialized by NASECO |
| Uganda | WE6108 | NPT2 | |||
| Uganda | WE5136 | NPT2 | |||
| Uganda | WE5139 | NPT2 | |||
| Uganda | WE5141 | NPT2 |
Second Generation MLN Tolerant/ Resistant Hybrids
Eleven different second-generation CIMMYT-derived MLN resistant hybrids are presently under NPTs in Kenya, Tanzania and Uganda. These have higher levels of MLN resistance to the first generation hybrids, with much lesser yield loss under severe MLN incidence (as tested at Naivasha screening site under artificial inoculation).
- CKH12600 (CHMLND0086) on the left and WH507 on the right. CKH12600 in release process in two countries in EA 2014.
- CKH12613 (right) under natural infestation near Arusha. This hybrid was entered into 2014 NPT in Tanzania.
- CKH13606 (left) and H614D (right). CKH13606 currently in 2015 NPT in Kenya.
- MLN trial performance 60 days after first post-inoculation, with distinct resistance performance of CIMMYT MLN resistant hybrids along with susceptible commercial check at MLN screening facility at Naivasha under artificial condition.
- MLN trial performance 60 days after first post-inoculation, with distinct resistance performance of CIMMYT MLN resistant hybrids along with susceptible commercial check at MLN screening facility at Naivasha under artificial condition.
- MLN-resistant three-way hybrid vs. susceptible commercial check. (a) ears of a MLN-resistant hybrid currently in NPT; (b) ears of a MLN-susceptible commercial check; (c) a MLN-resistant CIMMYT-derived pre-commercial hybrid (just before harvest) at the MLN Screening Facility at Naivasha; (d) a susceptible commercial hybrid check (at the same stage) at Naivasha (in April 2016).