Classification of selected white tropical maize inbred lines into heterotic groups using yield combining ability effects

Abstract An efficient hybrid breeding program defines and utilizes few heterotic groups. The objectives of this study were to determine genetic diversity and alignment of South Africa maize inbred lines collection towards tropical and temperate testers. Forty-two maize inbred lines were genotyped with 56110 single nucleotide polymorphism (SNP) DNA markers, using the Illumina MaizeSNP50 Bead chip. The 42 lines were crossed to two tropical and two temperate inbred line testers. The testcrosses were evaluated across seven environments, in South Africa, during 2014-2016. Genotypes and specific combining ability (SCA) effects of hybrids were significantly different (P<0.05) for grain yield. There was a weak correlation between molecular genetic distances and both grain yield mean and specific combining ability effects of hybrids, indicating that productivity of maize inbred lines could not be reliably determined based on molecular genetic distances. The SCA data was capable of classifying these maize inbred lines into three heterotic groups with respect to both tropical and temperate testers. Only a few lines could not be grouped on the basis of SCA data. The study also indicated high level of diversity among the maize inbred lines, which was shown by both the dendogram and molecular genetic distances. The SNP marker data classified the inbred lines into 11 clusters that could be simplified into three major groups of normal maize endosperm and two groups of quality protein maize (QPM) endosperm types. However, the SNP data indicated that maize lines were more aligned towards tropical than temperate inbred testers. This information would be useful for simplifying heterotic classification of the lines with profound implications for breeding progress.

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Combining ability and heterotic orientation of mid-altitude sub-humid tropical maize inbred lines for grain yield and related traits

African Journal of Plant Science ◽

10.5897/ajps2016.1502 ◽

2017 ◽

Vol 11 (6) ◽

pp. 229-239 ◽

Cited By ~ 2

Author(s):

Keno Tolera ◽

Worku Mosisa ◽

Zeleke Habtamu

Keyword(s):

Grain Yield ◽

Combining Ability ◽

Inbred Lines ◽

Tropical Maize ◽

Maize Inbred Lines

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Combining ability of tropical maize inbred lines under drought stress conditions

Cropp Breeding and Applied Biotechnology ◽

10.12702/1984-7033.v02n02a16 ◽

2002 ◽

Vol 2 (2) ◽

pp. 291-298 ◽

Cited By ~ 1

Author(s):

G.F.O.M. Durães ◽

P.C. Magalhães ◽

A.C. Oliveira ◽

M.X. Santos ◽

E.E.G. Gomes ◽

...

Keyword(s):

Drought Stress ◽

Combining Ability ◽

Inbred Lines ◽

Stress Conditions ◽

Tropical Maize ◽

Maize Inbred Lines

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Combining ability and gene action for maturity and agronomic traits in different heterotic groups of maize inbred lines and their diallel crosses

Journal of Crop Science and Biotechnology ◽

10.1007/s12892-012-0030-1 ◽

2012 ◽

Vol 15 (3) ◽

pp. 219-229 ◽

Cited By ~ 6

Author(s):

Afshar. Estakhr ◽

Bahram. Heidari

Keyword(s):

Combining Ability ◽

Gene Action ◽

Agronomic Traits ◽

Inbred Lines ◽

Heterotic Groups ◽

Diallel Crosses ◽

Maize Inbred Lines

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Combining ability and genetic divergence among tropical maize inbred lines using SSR markers

Acta Scientiarum Agronomy ◽

10.4025/actasciagron.v43i1.53317 ◽

2021 ◽

Vol 43 ◽

pp. e53317

Author(s):

Tauana Gibim Eisele ◽

Dener Lazzari ◽

Tereza Aparecida da Silva ◽

Ronald José Barth Pinto ◽

Robson Akira Matsuzaki ◽

...

Keyword(s):

Grain Yield ◽

Ssr Markers ◽

Genetic Divergence ◽

Combining Ability ◽

Inbred Lines ◽

Simultaneous Increase ◽

Additive Effects ◽

Tropical Maize ◽

Maize Inbred Lines ◽

Ear Height

Our objectives were to evaluate general and specific combining ability (SCA) and genetic divergence among tropical maize inbred lines using single sequence repeat (SSR) markers. Thirteen inbred lines were crossed based on a complete diallel scheme. Hybrids and three checks were evaluated in a lattice experimental design. Silk and anthesis flowering, average plant height, average ear height, white spot (Pantoea ananatis) and gray leaf spot (Cercospora zeae-maydis) severity, and grain yield were evaluated. Significant differences (p < 0.05) for general and specific combining abilities were observed for all traits. Based on additive effects, inbred lines 1 (Flash) and 12 (SG 6015) were selected to reduce the flowering period and plant and ear height. Inbred lines 2 (CD 303) and 3 (AG 8080) were selected to reduce disease severity. For the simultaneous increase in grain yield and reduced severity of diseases, line 11 (AG 9090) as a parent or tester in topcross schemes is recommended. According to non-additive effects, crosses 2 (CD 303) × 13 (DKB 747) and 11 (AG 9090) × 12 (SG 6015) were selected for grain yield and future breeding programs. Six groups were identified using SSR markers; a major group contained six inbred lines. Because of the minor relationship between genetic divergence and SCA effects on grain yield limits, the use of the groups for future divergent crosses is recommended.

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Enhancing Drought Tolerance and Striga hermonthica Resistance in Maize Using Newly Derived Inbred Lines from the Wild Maize Relative, Zea diploperennis

Agronomy ◽

10.3390/agronomy11010177 ◽

2021 ◽

Vol 11 (1) ◽

pp. 177

Author(s):

Abdulwahab S. Shaibu ◽

Baffour Badu-Apraku ◽

Monininuola A. Ayo-Vaughan

Keyword(s):

Drought Tolerance ◽

Grain Yield ◽

Combining Ability ◽

Inbred Lines ◽

Wild Relatives ◽

Striga Hermonthica ◽

Tropical Maize ◽

Heterotic Groups ◽

Maize Germplasm ◽

Zea Diploperennis

Recurrent drought and Striga hermonthica (Del.) Benth parasitism constrains maize production in sub-Saharan Africa (SSA). Transfer of resistance genes from wild relatives can improve resistance to drought and Striga in tropical maize. The objectives of this study were to (i) determine the combining ability of 12 extra-early yellow maize inbreds derived from Zea diploperennis and tropical maize germplasm; (ii) classify the inbreds into heterotic groups using heterotic grouping based on the general combining ability (GCA) of multiple traits (HGCAMT) method; (iii) examine hybrid performance under contrasting environments; and (iv) examine the stability of hybrid combinations involving the inbreds. Sixty-six diallel crosses involving the inbreds plus four checks were evaluated for two years under drought, Striga-infested and rainfed environments in Nigeria. Significant differences (p < 0.05) were observed for the effects of genotype, environment, genotype × environment, GCA and specific combining ability (SCA) on grain yield and other measured traits. Inbred lines such as TZdEEI 7 × TZEEI 63 derived from Z. diploperennis and tropical germplasm exceeded the checks by a range of 28 to 41%. Across environments, the hybrid TZdEEI 1 × TZdEEI 7, which was derived from Z. diploperennis, was the highest-yielding with a grain yield of 4302 kg ha−1. The results revealed the predominance of GCA over SCA effects for most measured traits, suggesting that additive gene action governed the inheritance of Striga resistance and drought tolerance related traits in the inbreds. The 12 inbreds were classified into three heterotic groups, while TZEEI 79 and TZdEEI 7 were identified as inbred testers and TZdEEI 7 × TZEEI 12 as a single-cross tester across environments. Hybrid TZdEEI 9 × TZEEI 79 was the highest-yielding and most stable. Other promising hybrids were TZdEEI 7 × TZEEI 79, TZdEEI 1 × TZdEEI 7 and TZdEEI 12 × TZEEI 95. These hybrids should be extensively tested on-farm for potential commercialization in SSA. Overall, our results highlighted the importance of harnessing beneficial alleles from wild relatives of maize for improvement of resistance to Striga and tolerance to drought in adapted maize germplasm.

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