Agronomic and molecular evaluation of maize inbred lines for drought tolerance

Drought is a severe threat to maize yield stability in Serbia and other temperate Southeast European countries occurring occasionally but with significant yield losses. The development of resilient genotypes that perform well under drought is one of the main focuses of maize breeding programmes. To test the tolerance of newly developed elite maize inbred lines to drought stress, field trials for grain yield performance and anthesis silk interval (ASI) were set in drought stressed environments in 2011 and 2012. Inbred lines performing well under drought, clustered into a group with short ASI and a smaller group with long ASI, were considered as a potential source for tolerance. The former contained inbreds from different heterotic groups and with a proportion of local germplasm. The latter consisted of genotypes with mixed exotic and Lancaster germplasm, which performed better in more drought-affected environments. Three inbreds were selected for their potential drought tolerance, showing an above-average yield and small ASI in all environments. Association analysis indicated significant correlations between ASI and grain yield and three microsatellites (bnlg1525, bnlg238 and umc1025). Eight alleles were selected for their favourable concurrent effect on yield increase and ASI decrease. The proportion of phenotypic variation explained by the markers varied across environments from 5.7% to 22.4% and from 4.6% to 8.1% for ASI and yield, respectively. The alleles with strongest effect on performance of particular genotypes and their interactions in specific environments were identified by the mean of partial least square interactions analysis indicating potential suitability of the makers for tolerant genotype selection.

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Evaluation of Yield-Based Low Nitrogen Tolerance Indices for Screening Maize (Zea mays L.) Inbred Lines

Agronomy ◽

10.3390/agronomy9050240 ◽

2019 ◽

Vol 9 (5) ◽

pp. 240 ◽

Cited By ~ 2

Author(s):

Zhixin Zhao ◽

Kunhui He ◽

Zhiqian Feng ◽

Yanan Li ◽

Liguo Chang ◽

...

Keyword(s):

Grain Yield ◽

Geometric Mean ◽

Inbred Lines ◽

Shaanxi Province ◽

High Yield ◽

Tolerance Index ◽

Heterotic Groups ◽

Maize Inbred Lines ◽

Low Nitrogen Tolerance ◽

Low Nitrogen

To screen the desired criterion to identify desirable genotypes and select genotypes best suited to limited nitrogen availability in order to facilitate the practice of low-nitrogen-tolerant breeding in maize, the response of 31 maize inbred lines, containing four control inbred lines (PH6WC, PH4CV, Zheng58, and Chang7-2) and others selected from the Shaan A and Shaan B heterotic groups cultivated at Northwest A&F University (Yangling, Shaanxi, China), were evaluated. The experiment was conducted following a split plot design with two replications during three growing seasons (2015, 2016, and 2017) under both high nitrogen (HN) and low nitrogen (LN) conditions at the Yulin and Yangling in Shaanxi Province, China. Seven screening indices, based on grain yield under two contrasting nitrogen (N) conditions, the stress susceptibility index (SSI), yield stability index (YSI), mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), harmonic mean (HM), and low nitrogen tolerance index (LNTI), were computed to assess the overall index that accurately screened the desirable genotypes. The results of the correlation analyses and principal component analysis showed that MP, GMP, HM and STI were correlated with grain yield significantly and positively under contrasting N conditions, and were able to accurately discriminate the desirable genotypes. Compared with the control inbred lines, many inbred lines selected from the Shaan A and Shaan B groups showed a higher LN tolerance. This shows that we can effectively improve the LN tolerance of maize inbred lines through LN screening. Based on the screening indices, the three-dimensional diagram and genotype and genotype × environment (GGE) biplots are agreed with this results, and we identified KA105, KB081, KA225, 91227, and 2013KB-47 as the desired genotypes that have the potential to be used to breed a high yield and stable hybrid.

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Microsatellite marker-based genetic diversity of tropical-adapted shrunken-2 maize inbred lines and its relationship with normal endosperm inbred lines of known heterotic classification

Plant Genetic Resources ◽

10.1017/s1479262120000489 ◽

2021 ◽

pp. 1-8

Author(s):

J. E. Iboyi ◽

A. Abe ◽

V. O. Adetimirin

Keyword(s):

Genetic Diversity ◽

Gene Diversity ◽

Polymorphic Information Content ◽

Inbred Lines ◽

Heterotic Group ◽

Germplasm Management ◽

Maize Breeding ◽

Heterotic Groups ◽

Maize Population ◽

Maize Inbred Lines

Abstract Knowledge of the genetic diversity and relationships among maize inbred lines can facilitate germplasm management and plant breeding programmes. The study investigated the level of genetic diversity among S6 lines developed from a tropical-adapted shrunken-2 (sh-2) maize population and their relationship with normal endosperm tropical inbred lines of known heterotic groups. Ninety-one sh-2 maize inbred lines (UI1-UI91) developed in the University of Ibadan super-sweet Maize Breeding Programme were genotyped at 30 simple sequence repeat (SSR) loci, alongside five normal endosperm maize inbred lines viz. TZi3, TZi4, TZi10, TZi12 and TZi15, four of which belong to two heterotic groups. Twenty-three SSR markers were polymorphic and detected a total of 61 alleles, with a range of 2–7 and an average of 2.65 alleles per locus. The polymorphic information content ranged from 0.12 in bnlg1937 to 0.77 in phi126, with an average of 0.36. The gene diversity (He) averaged 0.43. Cluster analysis resulted in five groups consisting of 16, 36, 17, 23 and 3 inbred lines, with one sh-2 line ungrouped. TZi 12 and TZi 15, both of which are of the same heterotic group, clustered with TZi 3 of another heterotic group. Considerable genetic diversity exists among the 96 inbred lines. Only two of the five normal endosperm lines shared clusters with the sh-2 lines. The clustering of the normal endosperm inbred lines is not related to their established heterotic patterns. Inbred lines in two clusters offer the possibility of guiding the exploitation of heterosis among the sh-2 lines.

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Genetic Diversity and Heterotic Orientation of South Africa Maize Inbred Lines Towards Tropical and Temperate Testers

10.21203/rs.3.rs-173281/v1 ◽

2021 ◽

Author(s):

Siphiwokuhle Funani Shandu ◽

John Derera ◽

Kingston Mashingaidze ◽

Edmore Gasura

Keyword(s):

South Africa ◽

Genetic Diversity ◽

Grain Yield ◽

Combining Ability ◽

Molecular Genetic ◽

Inbred Lines ◽

Genetic Distances ◽

Specific Combining Ability ◽

Heterotic Groups ◽

Maize Inbred Lines

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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Characterization of maize inbred lines based on molecular markers, heterosis and pedigree data

Genetika ◽

10.2298/gensr0703355s ◽

2007 ◽

Vol 39 (3) ◽

pp. 355-363 ◽

Cited By ~ 4

Author(s):

Jelena Srdic ◽

Snezana Mladenovic-Drinic ◽

Zorica Pajic ◽

Milomir Filipovic

Keyword(s):

Genetic Diversity ◽

Cluster Analysis ◽

Molecular Markers ◽

Rapd Markers ◽

Inbred Lines ◽

Protein Markers ◽

Pedigree Data ◽

Maize Breeding ◽

Heterotic Groups ◽

Maize Inbred Lines

Information about the genetic diversity of inbred lines is essential in planning maize breeding programmes. Utilization of diverse parents in the process of hybridization has the greatest influence on producing high yielding hybrids. The aim of this research was to determine genetic diversity of ten maize inbred lines of different origin on the basis of protein and RAPD markers and to compare these results with pedigree and grain yield heterosis data. Results of genetic distances, based on protein and RAPD markers were similar and in concurrence with the date on the origin of inbreds. Usefulness of protein and RAPD markers for assigning inbreds to heterotic groups was examined by the cluster analysis. Cluster analysis based on protein markers, RAPD and heterosis showed clear grouping of lines into two main heterotic groups. Only few deviations were noticed, and those among inbreds not belonging to those heterotic groups. According to the observed results it could be concluded that grouping of inbred lines based on molecular markers, generally agrees with their pedigrees and that clusters are representatives of heterotic groups. Very high and highly significant estimate of rank correlation coefficient between RAPD and heterosis (0,876**) also confirmed that.

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Resistance in Maize Inbred Lines to Fusarium verticillioides and Fumonisin Accumulation in South Africa

Plant Disease ◽

10.1094/pdis-08-11-0695 ◽

2012 ◽

Vol 96 (6) ◽

pp. 881-888 ◽

Cited By ~ 26

Author(s):

I. M. Small ◽

B. C. Flett ◽

W. F. O. Marasas ◽

A. McLeod ◽

M. A. Stander ◽

...

Keyword(s):

South Africa ◽

Fusarium Verticillioides ◽

Field Trials ◽

Inbred Lines ◽

Fusarium Ear Rot ◽

Ear Rot ◽

Maize Breeding ◽

Sources Of Resistance ◽

Breeding Lines ◽

Maize Inbred Lines

Fusarium ear rot of maize, caused by Fusarium verticillioides, is an important disease affecting maize production worldwide. Apart from reducing yield and grain quality, F. verticillioides produces fumonisins which have been associated with mycotoxicoses of animals and humans. Currently, no maize breeding lines are known with resistance to F. verticillioides in South Africa. The objective of this study, therefore, was to evaluate 24 genetically diverse maize inbred lines as potential sources of resistance to Fusarium ear rot and fumonisin accumulation in field trials at Potchefstroom and Vaalharts in South Africa. After artificial silk channel inoculation with F. verticillioides, Fusarium ear rot development was determined at harvest and fumonisins B1, B2, and B3 quantified. A significant inbred line by location effect was observed for Fusarium ear rot severity (P ≤ 0.001), although certain lines proved to be consistently resistant across both locations. The individual inbred lines also differed considerably in fumonisin accumulation between Potchefstroom and Vaalharts, with differentiation between susceptible and potentially resistant inbred lines only being possible at Vaalharts. A greenhouse inoculation trial was then also performed on a subset of potentially resistant and highly susceptible lines. The inbred lines CML 390, CML 444, CML 182, VO 617Y-2, and RO 549 W consistently showed a low Fusarium ear rot (<5%) incidence at both Potchefstroom and Vaalharts and in the greenhouse. Two of these inbred lines, CML 390 and CML 444, accumulated fumonisin levels <5 mg kg–1. These lines could potentially act as sources of resistance for use within a maize breeding program.

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Identification of QTL-s for drought tolerance in maize, II: Yield and yield components

Genetika ◽

10.2298/gensr1302341n ◽

2013 ◽

Vol 45 (2) ◽

pp. 341-350 ◽

Cited By ~ 9

Author(s):

Ana Nikolic ◽

Violeta Andjelkovic ◽

Dejan Dodig ◽

Snezana Mladenovic-Drinic ◽

Natalija Kravic ◽

...

Keyword(s):

Drought Tolerance ◽

Grain Yield ◽

Yield Components ◽

Phenotypic Variability ◽

Interval Mapping ◽

Field Trials ◽

Chromosome 9 ◽

Yield Potential ◽

Maize Breeding ◽

Yield And Yield Components

Grain yield is the primary trait of interest in maize breeding programs. Worldwide, drought is the most pervasive limitation to the achievement of yield potential in maize. Drought tolerance of maize has been considerably improved through conventional breeding. Traditional breeding methods have numerous limitations, so development of new molecular genetics techniques could help in elucidation of genetic basis of drought tolerance .In order to map QTLs underlying yield and yield components under drought 116 F3 families of DTP79xB73 cross were evaluated in the field trials. Phenotypic correlations calculated using Pearson?s coefficients were high and significant. QTL detection was performed using composite interval mapping option in WinQTL Cartographer v 2.5. Over all nine traits 45 QTLs were detected: five for grain yield per plant and 40 for eight yield components. These QTLs were distributed on all chromosomes except on chromosome 9. Percent of phenotypic variability determined for the identified QTLs for all the traits was in the range from 27.46 to 95.85%. Different types of gene action were found for the QTLs identified for analyzed traits.

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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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Partial diallel and genetic divergence analyses in maize inbred lines

Acta Scientiarum Agronomy ◽

10.4025/actasciagron.v43i1.53540 ◽

2020 ◽

Vol 43 ◽

pp. e53540

Author(s):

Maria Fernanda de Souza Dias Maioli ◽

Ronald José Barth Pinto ◽

Tereza Aparecida da Silva ◽

Diego Ary Rizzardi ◽

Robson Akira Matsuzaki ◽

...

Keyword(s):

Grain Yield ◽

Genetic Divergence ◽

Block Design ◽

Inbred Lines ◽

Group Method ◽

Arithmetic Average ◽

Pair Group ◽

Maize Inbred Lines ◽

Randomized Block Design ◽

Partial Diallel

In this study, we aimed to estimate general and specific combining abilities (GCA and SCA, respectively) and to verify genetic divergence (Rogers distance, Unweighted Pair-Group Method Using Arithmetic Average - UPGMA) using microsatellite markers in maize inbred lines. Using a partial diallel scheme, a total of 19 inbred lines were crossed as (9 x 10), which were derived from the single hybrids SG6015 and P30F53, respectively. The 90 hybrids were evaluated in an incomplete randomized block design with common checks and three replications during the 2017-2018 growing season. Flowering time, average plant height, ear height insertion, average ear diameter, ear length, number of lodged and broken plants, mass of 100 grains and grain yield were measured. According to the analysis of variance, GCA, and SCA were significant (p < 0.05) in all the measured traits; inbred line B as well as 1 and 8, derived from the single hybrids SG6015 and P30F53, respectively, were selected due to their higher GCA values in grain yield to be used in crosses as testers, while the single cross hybrid (B x 1) was selected due to their higher SCA value in grain yield to be used in future breeding programs. The molecular marker analysis divided the inbred lines into two groups, where the highest dissimilarity (0.74) was observed between lines A and 9; however, these did not result in a high SCA value, therefore the hybrids obtained by such crossings were not selected for grain yield.

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COMBINING ABILITIES OF GRAIN YIELD AND YIELD RELATED TRAITS IN RELATION TO DROUGHT TOLERANCE IN TEMPERATE MAIZE BREEDING

Turkish Journal Of Field Crops ◽

10.17557/tjfc.40425 ◽

2015 ◽

Vol 20 (2) ◽

Cited By ~ 1

Author(s):

Sekip ERDAL ◽

Mehmet PAMUKCU ◽

Ahmet OZTURK ◽

Köksal AYDINSAKIR ◽

Suleyman SOYLU

Keyword(s):

Drought Tolerance ◽

Grain Yield ◽

Maize Breeding ◽

Combining Abilities

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Phenotypic and molecular characterization of a set of tropical maize inbred lines from a public breeding program in Brazil

BMC Genomics ◽

10.1186/s12864-021-08127-7 ◽

2022 ◽

Vol 23 (1) ◽

Author(s):

Sirlene Viana de Faria ◽

Leandro Tonello Zuffo ◽

Wemerson Mendonça Rezende ◽

Diego Gonçalves Caixeta ◽

Hélcio Duarte Pereira ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Inbred Lines ◽

Breeding Program ◽

Tropical Maize ◽

Maize Breeding ◽

Breeding Programs ◽

The Public ◽

Maize Inbred Lines

Abstract Background The characterization of genetic diversity and population differentiation for maize inbred lines from breeding programs is of great value in assisting breeders in maintaining and potentially increasing the rate of genetic gain. In our study, we characterized a set of 187 tropical maize inbred lines from the public breeding program of the Universidade Federal de Viçosa (UFV) in Brazil based on 18 agronomic traits and 3,083 single nucleotide polymorphisms (SNP) markers to evaluate whether this set of inbred lines represents a panel of tropical maize inbred lines for association mapping analysis and investigate the population structure and patterns of relationships among the inbred lines from UFV for better exploitation in our maize breeding program. Results Our results showed that there was large phenotypic and genotypic variation in the set of tropical maize inbred lines from the UFV maize breeding program. We also found high genetic diversity (GD = 0.34) and low pairwise kinship coefficients among the maize inbred lines (only approximately 4.00 % of the pairwise relative kinship was above 0.50) in the set of inbred lines. The LD decay distance over all ten chromosomes in the entire set of maize lines with r2 = 0.1 was 276,237 kb. Concerning the population structure, our results from the model-based STRUCTURE and principal component analysis methods distinguished the inbred lines into three subpopulations, with high consistency maintained between both results. Additionally, the clustering analysis based on phenotypic and molecular data grouped the inbred lines into 14 and 22 genetic divergence clusters, respectively. Conclusions Our results indicate that the set of tropical maize inbred lines from UFV maize breeding programs can comprise a panel of tropical maize inbred lines suitable for a genome-wide association study to dissect the variation of complex quantitative traits in maize, mainly in tropical environments. In addition, our results will be very useful for assisting us in the assignment of heterotic groups and the selection of the best parental combinations for new breeding crosses, mapping populations, mapping synthetic populations, guiding crosses that target highly heterotic and yielding hybrids, and predicting untested hybrids in the public breeding program UFV.

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