Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe
Monitoring genetic gain is required in crop improvement programs in order to assess the effectiveness of breeding initiatives. The periodic measurement of genetic gain will quantify the efficiency of new technologies incorporated into the program. Here, a total of 24 cultivars (20 released from Zimb...
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MDPI AG
2024-01-01
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| Series: | Agronomy |
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| Online Access: | https://www.mdpi.com/2073-4395/14/2/246 |
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| author | Purity Mazibuko Charles Mutengwa Cosmos Magorokosho Dumisani Kutywayo Casper Nyaradzai Kamutando |
| author_facet | Purity Mazibuko Charles Mutengwa Cosmos Magorokosho Dumisani Kutywayo Casper Nyaradzai Kamutando |
| author_sort | Purity Mazibuko |
| collection | DOAJ |
| description | Monitoring genetic gain is required in crop improvement programs in order to assess the effectiveness of breeding initiatives. The periodic measurement of genetic gain will quantify the efficiency of new technologies incorporated into the program. Here, a total of 24 cultivars (20 released from Zimbabwe’s National Breeding program (ZNBP) plus 4 released by the largest and oldest private seed company in Zimbabwe, Seed Co) over the period of 1900–2016, were evaluated across 10 locations in Zimbabwe. The testing locations represented agro-ecologies where maize is optimally grown and where maize production is under threat from climate change-induced abiotic stresses, particularly drought and heat stress, in Zimbabwe. The 24 cultivars were laid out across all the locations using the alpha (0.1) lattice design replicated two times with six incomplete blocks nested in each of the replicates. The genetic gains were estimated at 61 kg ha<sup>−1</sup> yr<sup>−1</sup>, 25 kg ha<sup>−1</sup> yr<sup>−1</sup>, 6 kg ha<sup>−1</sup> yr<sup>−1</sup>, and 2 kg ha<sup>−1</sup> yr<sup>−1</sup> under optimal, random drought stress, heat stress, and managed drought stress conditions, respectively. The results were comparable with those from other studies where newly released cultivars yielded more than old cultivars. Overall, the results demonstrated that over a century, the ZNBP has been making significant progress in yield increments in its maize genotypes. |
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| issn | 2073-4395 |
| language | English |
| last_indexed | 2024-03-07T22:46:54Z |
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| series | Agronomy |
| spelling | doaj.art-c38bda86b9904ec2a48521f89b820e1e2024-02-23T15:03:58ZengMDPI AGAgronomy2073-43952024-01-0114224610.3390/agronomy14020246Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of ZimbabwePurity Mazibuko0Charles Mutengwa1Cosmos Magorokosho2Dumisani Kutywayo3Casper Nyaradzai Kamutando4Department of Agronomy, Faculty of Science and Agriculture, University of Fort Hare, Alice P.O. Box X1314, South AfricaDepartment of Agronomy, Faculty of Science and Agriculture, University of Fort Hare, Alice P.O. Box X1314, South AfricaFormer International Maize and Wheat Improvement Center (CIMMYT), 12.5 km peg, New Mazowe Road, Mt. Pleasant, Harare P.O. Box MP163, ZimbabweDepartment of Research and Specialist Services, Causeway, Harare P.O. Box CY550, ZimbabweDepartment of Plant Production Sciences and Technologies, University of Zimbabwe, Mount Pleasant, Harare P.O. Box MP167, ZimbabweMonitoring genetic gain is required in crop improvement programs in order to assess the effectiveness of breeding initiatives. The periodic measurement of genetic gain will quantify the efficiency of new technologies incorporated into the program. Here, a total of 24 cultivars (20 released from Zimbabwe’s National Breeding program (ZNBP) plus 4 released by the largest and oldest private seed company in Zimbabwe, Seed Co) over the period of 1900–2016, were evaluated across 10 locations in Zimbabwe. The testing locations represented agro-ecologies where maize is optimally grown and where maize production is under threat from climate change-induced abiotic stresses, particularly drought and heat stress, in Zimbabwe. The 24 cultivars were laid out across all the locations using the alpha (0.1) lattice design replicated two times with six incomplete blocks nested in each of the replicates. The genetic gains were estimated at 61 kg ha<sup>−1</sup> yr<sup>−1</sup>, 25 kg ha<sup>−1</sup> yr<sup>−1</sup>, 6 kg ha<sup>−1</sup> yr<sup>−1</sup>, and 2 kg ha<sup>−1</sup> yr<sup>−1</sup> under optimal, random drought stress, heat stress, and managed drought stress conditions, respectively. The results were comparable with those from other studies where newly released cultivars yielded more than old cultivars. Overall, the results demonstrated that over a century, the ZNBP has been making significant progress in yield increments in its maize genotypes.https://www.mdpi.com/2073-4395/14/2/246drought stressheat stressgenetic gainsyield gainsmaize breeding |
| spellingShingle | Purity Mazibuko Charles Mutengwa Cosmos Magorokosho Dumisani Kutywayo Casper Nyaradzai Kamutando Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe Agronomy drought stress heat stress genetic gains yield gains maize breeding |
| title | Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe |
| title_full | Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe |
| title_fullStr | Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe |
| title_full_unstemmed | Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe |
| title_short | Genetic Gains of Grain Yield among the Maize Cultivars Released over a Century from the National Breeding Program of Zimbabwe |
| title_sort | genetic gains of grain yield among the maize cultivars released over a century from the national breeding program of zimbabwe |
| topic | drought stress heat stress genetic gains yield gains maize breeding |
| url | https://www.mdpi.com/2073-4395/14/2/246 |
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