DEVELOPMENT OF EXTRA-EARLY, EARLY, AND INTERMEDIATE MATURING DROUGHT TOLERANT MAIZE VARIETIES IN GHANA K. Obeng-Antwi, PhD Maize Improvement-CSIR CRI

Research Team K. Obeng-Antwi, Breeder, CRI-Leader M.B. Ewool, Breeder, CRI M. Tengan, Breeder, CRI Frank Danso, Agronomist, CRI P. Adusei-Akowuah, CRI, Seed Technologist H. Asumadu, Agronomist, CRI Dr. M. Owusu-Akyaw/M. B. Mochiah, Entomologists, CRI M.S. Abdulai, Breeder, SARI Haruna Halidu, Breeder, SARI Agnes Ankomah- Biometrician, CRI J. T. Manful, Food Technologist, FRI H. Adu-Dapaah, CRI Director, Overall coordination

GOAL To develop and promote the production and utilization of high and stable yielding open- pollinated and hybrid maize varieties that are tolerant to the major biotic and abiotic stresses in Ghana to promote food security and increase farmers’ income.

Objectives  To identify high and stable yielding DT maize germplasm  Develop EVs, hybrids and synthetics from this germplasm  Evaluate promising varieties in multi-location trials  Release superior DT varieties to farmers in Ghana and other interested national programmes.  Produce breeders’ seeds of released DT maize varieties for interested stakeholders, eg. GLDB

Major Research Activities in 2011  Purification of parental lines of released hybrids (Mamaba, Etubi, Enibi)  Seed increase of breeding materials in the programme, DT varieties, and extra-early and early maturing DT inbred lines from IITA.  Single cross hybrid formation/evaluation using IITA extra-early and early maturing DT inbred lines.  Evaluation of extra-early hybrids selected from Regional Trials during 2010 monitoring

Major Research Activities in 2011  Topcross formation using early maturing inbred lines from IITA  Evaluation of experimental varieties on-station to identify superior stable yielding varieties  Breeder seed production and maintenance of hybrid parental lines and other released varieties

RESULTS

Seed Increase of Extra-early and Early Maturing DT Inbred Lines from IITA  A total of 64 DT inbred lines from IITA made up of 35 early and 29 extra-early maturities were multiplied at Fumesua.  Various quantities of seeds of the lines were produced  Due to the late start of the major season in 2011, crossing of the lines which had been planned for the minor season could not be carried out.  Diallel crosses of these lines would be carried out in each of the maturity groups in 2012A and F1s evaluated in 2012B.

Seed Increase of DT Varieties for On-farm Activities in Ghana  During 2011B, seed increase of 13 DT early and extra-early varieties was carried out at Fumesua under irrigation at the request of the DTMA Working Group in Ghana.  This was done to reduce the over-dependence on IITA for seeds for on-farm activities in Ghana. Various quantities of seeds of the 13 varieties were produced, and will be used for DTMA on-farm activities in 2012.

Table 1: DT Seed Produced for On-Farm Activities in 2012 VarietyDescription Quantities Produced (kg) TZE Comp3 DT C2 F2Early OPV TZEE-Y STRExtra-early OPV TZEE-W Pop C4Extra-early OPV SYN EE-W STRExtra -early OPV5.2 TZE-W DT STR C4Early OPV0.5 EVDT-Y 2008 STREarly OPV TZEE-W STRExtra-early OPV2.9 TZE-W DT STR C4Early OPV4.0 DTSR-W C0 F2Early OPV2.7 TZE-Y DT STR C4Early OPV2.6 TZEE-W STR C5Extra-early OPV6.0

Formation and Evaluation of Early Maturing DT Single Crosses  Forty-six early maturing DT inbred lines were ordered from IITA in 2010  These lines were multiplied in Nyankpala in 2010, grown in the breeding nursery at Fumesua in 2011A and crosses made in all possible combinations.  Over 100 F1s developed; will be evaluated in 3 sites in 2012A (Fumesua, Ejura, Kpeve)

Formation and Evaluation of Extra- Early Maturing DT Single Crosses  Fifty-four extra-early maturing DT inbred lines were ordered from IITA in 2010  Lines were increased in the breeding nursery at Fumesua in 2010A and crosses made in all possible combinations in 2010B.  Over 100 F1s developed

Evaluation of Drought Tolerant Extra- Early Single Cross Hybrids  100 extra-early single cross hybrids were evaluated in a 3 location trial (Fumesua, Ejura and Kpeve) in 2011A  A 10x10 simple lattice design with two replications per site was used.  Plots were single rows, 5m long, hills were spaced 40 cm within rows, and rows spaced 75 cm apart; 3 seeds/hill planted and thinned to 2 at establishment (66,600 plants/ha)

Table 2: Grain yields (t/ha) of Extra-Early Single Cross Hybrids Evaluated over Three Locations in the Forest and Transition Zones of Ghana During the Major Season of 2011 Entry NameFumesuaEjuraKpeveAcross TZEEI-6 x TZEEI TZEEI-15 x TZEEI TZEEI-23 x TZEEI TZEEI-8 x TZEEI TZEEI-1 x TZEEI TZEEI-5 x TZEEI TZEEI-11 x TZEEI TZEEI-23 x TZEEI TZEEI-5 x TZEEI TZEEI-14 x TZEEI Grand Mean (30 entries) Lsd (0.05) CV (%)

Table 3: Agronomic Characteristics of Single Cross Hybrids Evaluated over Three Locations in the Forest and Transition Zones of Ghana During the Major Season of 2011 Entry Name Plant height (cm) Ear height (cm) Days to flowering StreakRustBlight TZEEI-6 x TZEEI TZEEI-15 x TZEEI TZEEI-23 x TZEEI TZEEI-8 x TZEEI TZEEI-1 x TZEEI TZEEI-5 x TZEEI TZEEI-11 x TZEEI TZEEI-23 x TZEEI TZEEI-5 x TZEEI TZEEI-14 x TZEEI Grand Mean Lsd (0.05) CV (%)

Topcross Formation Using Early Maturing DT Inbred Lines of Maize The objective was to develop topcrosses involving early maturing populations in the programme and inbred lines from IITA for evaluation

Topcross Formation Using Early Maturing DT Inbred Lines of Maize  Sixty-two topcrosses were made using 9 populations in the local programme  No. of crosses made with the inbred lines were as follows: - Abontem (10) - Fu 2090 DWDP (13) - TZEE-Y-Pop DT STR C 4 (2) - GH 90-DYFP (1) - TZE-Y-Pop DT STR C 4 (8)

Topcross Formation Using Early Maturing DT Inbred Lines of Maize - TZE-W Pop DT STR C 3 (4) - Fu 2080 DWDP (12) - TZE-W Pop DT STR C 3 (9) - TZE-W-Pop-DT STR C 4 (1)  Topcrosses will be constituted into a trial and evaluated at three sites (Fumesua, Ejura and Akomadan) during the major season.

Evaluation of Materials Selected from Regional Trials During Monitoring  Several promising extra-early OP and hybrid varieties from IITA were identified during monitoring tour in northern Ghana in  Selections included OPVs, single, three-way, double and top-cross hybrids  The hybrids were constituted into a trial and evaluated across four sites (Forest, Transition and Guinea Savannah zones) in 2011A

Table 4: Grain yields (t/ha) of selected extra-early maize hybrid varieties evaluated in 4 locations in the Forest, Forest Transition and Guinea Savannah zones of Ghana in Entry NameF’suaEjuraN’kpalaD’goAcross EEWH-13 (TZEE-W POP STR C5 x TZEEI 29) EEWH-9 (TZEEI 29 x TZEE1 21) x (TZEEI 14 x TZEEI 37) EEWH-21 (TZEEI 29 x TZEEI 21) EEYH-17 (TZEE-Y POP STR C5 x TZEEI 63) TZEEI 1 x TZEEI EEWH-11 (TZEEI 29 x TZEEI 37) x (TZEEI 4 x TZEEI 14) EEYH-15 (TZEE - POP STR C5 X TZEEI 82) EEWH-17 (TZEEI - W POP STR C5 x TZEEI 21) EEYH-14 (TZEE-Y POP STR C5 x TZEEI 78) EEWH-19 (TZEEI 29 x TZEEI 49) EEYH-16 (TZEE-Y POP STR C5 x TZEEI 58) EEWH-7 (TZEEI 29 x TZEEI 37) x TZEEI EEYH-24 (TZEEI 95 x TZEEI 78) Dodzie Grand Mean Lsd (0.05) CV (%)

Breeder Seed Production in 2011  Breeder seed fields were established at Fumesua during the major and minor seasons of 2011 for production of DT maize varieties in support of on- farm and community-based seed production schemes.  Seed increases of parental lines of Etubi, Enibi and Mamaba (Entries 5, 6, 70, 75 and 85) all popular QPM hybrids were undertaken  Breeders’ seed of Obatanpa and other popular OPVs were also produced

Table 5: Breeder Seed Production in 2011 Variety/LineDescription Quantities Produced (kg) ObatanpaQPM Open-Pollinated Variety200 Abontem Extra-early Drought Tolerant OPV 200 OmankwaEarly Drought Tolerant OPV140 AburohemaaEarly Drought Tolerant OPV40 AkposoeExtra-early OPV20 Entry 5Male parent for Mamaba400 Entry 6Female parent for GH Entry 70Male parent for GH Entry 75Male parent for Enibi500 Entry 85Male parent for Etubi 400

Table 6: Estimated Breeder Seed Production in 2012 Variety/LineDescription Quantities Produced (kg) ObatanpaQPM Open-Pollinated Variety400 Abontem Extra-early Drought Tolerant OPV 200 OmankwaEarly Drought Tolerant OPV200 AburohemaaEarly Drought Tolerant OPV200 AkposoeExtra-early OPV150 Entry 5Male parent for Mamaba300 Entry 6Female parent for GH Entry 70Male parent for GH Entry 75Male parent for Enibi200 Entry 85Male parent for Etubi 300

Summary/Conclusions  Results of preliminary screening of extra-early single cross hybrids indicated that the top 30 hybrids had potential yields ranging from 5.8 to 7.6 t/ha. These single crosses will be further tested in multi-location and on-farm trials and released to farmers.  Topcrosses involving local populations and IITA extra-early and early inbred lines have been formed for evaluation in 2012.

Summary/Conclusions  Breeders’ seed of parental lines for all local hybrids have been produced and are available for seed companies and interested individuals to access  Breeders’ seed of popular OP varieties such as Obatanpa have been produced for production of Foundation seed by GLDB and other interested stakeholders

Plans for 2012  Continue to order germplasm from local and international sources. Grow in the nursery and select adaptable genotypes and use as source materials for testing and release as varieties per se and for hybridization  Increase seed of ordered germplasm and initiate crosses amongst them for evaluation  Continue to purify and produce breeders’ seed of parental lines of local hybrids  Provide technical backstopping to the Commercialization Unit

Acknowledgements Bill and Melinda Gates Foundation DTMA Scientists in IITA Director, CSIR-CRI Staff of CSIR-CRI Maize Improvement Program

Thank You