Agronomic Performance ofStrigaResistant Early-Maturing Maize Varieties and Inbred Lines in the Savannas of West and Central Africa

Abstract Background Early maturing provitamin A (PVA) quality protein maize (QPM) inbred lines with tolerance to drought and low-N are needed to develop superior hybrids in West and Central Africa (WCA). This study aimed to (i) identify inbred lines that combined drought and low-N tolerance with increased levels of PVA and tryptophan and (ii) assess the relationship among PVA carotenoids, tryptophan and grain yield. Sixty-four inbred lines plus six inbred checks were evaluated under induced drought, low-N and optimal conditions in 2016 and 2017 in Nigeria. The inbred lines were assayed for PVA and tryptophan contents. Results Thirty-three of the lines were found to be tolerant to drought and low-N. Ninety percent of the inbred lines had tryptophan contents > 0.075 % per sample in whole grain substantiating the presence of the QPM trait in the inbred lines. Inbred lines TZEIORQ 55 and TZEIORQ 29 combined high PVA contents (15.38 and 12.10μg g-1, respectively) with low-N tolerance while nine inbred lines combined moderate PVA levels (5.06 – 8.34μg g-1) with drought and low-N tolerance. Conclusions These maize inbred lines could be utilized to develop superior drought and low-N tolerant hybrids and synthetics with elevated levels of PVA and tryptophan for WCA. The correlations observed among grain yield, PVA and tryptophan of the lines were not significant suggesting that these traits could be improved independently.

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Genetic Diversity, Population Structure and Inter-Trait Relationships of Combined Heat and Drought Tolerant Early-Maturing Maize Inbred Lines from West and Central Africa

Agronomy ◽

10.3390/agronomy10091324 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1324

Author(s):

Alimatu Sadia Osuman ◽

Baffour Badu-Apraku ◽

Beatrice E. Ifie ◽

Pangirayi Tongoona ◽

Ebenezer Obeng-Bio ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Polymorphic Information Content ◽

Central Africa ◽

Inbred Lines ◽

Heterotic Groups ◽

Maize Inbred Lines ◽

Wide Range ◽

Early Maturing ◽

West And Central Africa

Adequate knowledge and understanding of the genetic diversity and inter-trait relationships among elite maize inbred lines are crucial for determining breeding strategies and predicting hybrid performance. The objectives of this study were to investigate the genetic diversity of 162 early maturing white and yellow tropical maize inbred lines, and to determine the population structure, heterotic groups and inter-trait relationships among the lines. Using 9684 DArT single nucleotide polymorphism (SNP) markers, a gene diversity (GD) of 0.30 was recorded for the inbred lines with polymorphic information content (PIC) ranging from 0.08 to 0.38. The genetic relatedness among the inbred lines evaluated revealed six different groups based on the history of selection, colour of endosperm and pedigree. The genotype-by-trait (GT) biplot analysis identified inbred 1 (TZEI 935) as outstanding in terms of combined heat and drought (HD) tolerance with the base index analysis identifying 15 superior inbreds in the HD environment. A wide range of genetic variability was observed among the inbred lines, indicating that they are an invaluable resource for breeding for HD tolerance in maize breeding programmes, especially in West and Central Africa.

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MORPHOMETRIC CHARACTERIZATION OF Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) INFESTING DIFFERENTS MAIZE VARIETIES IN WEST AND CENTRAL AFRICA.

International Journal of Advanced Research ◽

10.21474/ijar01/5248 ◽

2017 ◽

Vol 5 (8) ◽

pp. 1821-1835

Author(s):

AdioumaGeorges RobertJacquesSarr ◽

◽

CheikhAbdouKhadre MbackéDia ◽

MamaRacky Ndiaye ◽

Déthie Ngom ◽

...

Keyword(s):

Central Africa ◽

Sitophilus Zeamais ◽

Maize Varieties ◽

West And Central Africa ◽

Morphometric Characterization

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Testcross performance and combining ability of early maturing maize inbreds under multiple-stress environments

Scientific Reports ◽

10.1038/s41598-019-50345-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Benjamin Annor ◽

Baffour Badu-Apraku ◽

Daniel Nyadanu ◽

Richard Akromah ◽

Morakinyo A. B. Fakorede

Keyword(s):

Grain Yield ◽

Combining Ability ◽

Central Africa ◽

Optimal Conditions ◽

Gene Effects ◽

Maize Production ◽

Multiple Stress ◽

Early Maturing ◽

Additive Gene ◽

West And Central Africa

Abstract Availability of multiple-stress tolerant maize is critical for improvement in maize production in West and Central Africa (WCA). A study was carried out to (i) assess a set of inbred lines for combining ability under stressed and optimal conditions, (ii) determine the performance of the testcrosses under different conditions, and (iii) identify outstanding hybrids across the conditions. Two hundred and five testcrosses were planted with five hybrid checks under Striga-infested, low soil nitrogen, drought and optimal conditions between 2015 and 2016 in Nigeria. The grain yield inheritance under optimal condition was largely regulated by additive gene effect whereas non-additive gene effects largely regulated grain yield under the three stresses. Four of the inbreds had significant positive general combining ability effects each under low N and drought, and three under Striga infestation for grain yield. The inbreds could be vital sources of beneficial alleles for development and improvement of tropical yellow maize hybrids and populations. Hybrids TZEI 443 x ENT 13 and TZEI 462 x TZEI 10 were high yielding and stable; they out-performed the three early maturing released hybrids in WCA. The new hybrids should be extensively assessed and released in the sub-region to improve food security.

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Assessment of genetic variability among accessions of okra (Abelmoschus esculentus L. Moench)

Acta Horticulturae et Regiotecturae ◽

10.2478/ahr-2021-0036 ◽

2021 ◽

Vol 24 (2) ◽

pp. 141-147

Author(s):

Richard Olayiwola ◽

Rukayat Ayomikun Yusuf ◽

Oyeboade Adebiyi Oyetunde ◽

Olufemi Sunday Sosanya ◽

Omolayo Johnson Ariyo

Keyword(s):

Genetic Diversity ◽

Genetic Variability ◽

Central Africa ◽

Principal Component ◽

Breeding Program ◽

Genetic Base ◽

Cropping Season ◽

Principal Component Analyses ◽

Early Maturing ◽

West And Central Africa

Abstract Okra yields are low in West and Central Africa and factors including narrow genetic base of available germplasm have been implicated. An assessment of genetic variability among germplasm from various sources and knowledge of trait contributions to these variations is crucial to the success of okra breeding program. Eighteen okra accessions were evaluated during the 2020 cropping season in Nigeria to assess the genotypes for genetic diversity, group the accessions into clusters and identify traits that chiefly accounted for the variations among the genotypes. Data obtained were subjected to analysis of variance (ANOVA), metroglyph and principal component analyses (PCA). ANOVA revealed significant accession mean squares for majority of the measured traits. Metroglyph analysis grouped the accessions into four clusters with members of Cluster IV generally high-yielding, early-maturing and short genotypes. NGB00353 and NGB00356 that were among genotypes with high total index scores were members of Cluster IV. The first four principal components (PCs) accounted for 80% of the total observed variation. PC1 with the highest discriminatory power was loaded with days to budding, internode length, pod yield.plot−1 and the number of pods.plant−1. The variation within and between clusters could be explored in okra breeding program.

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Genetic gains in grain yield under nitrogen stress following three decades of breeding for drought tolerance and Striga resistance in early maturing maize

The Journal of Agricultural Science ◽

10.1017/s0021859615000593 ◽

2015 ◽

Vol 154 (4) ◽

pp. 647-661 ◽

Cited By ~ 8

Author(s):

B. BADU-APRAKU ◽

M. A. B. FAKOREDE ◽

M. OYEKUNLE ◽

R. O. AKINWALE

Keyword(s):

Drought Tolerance ◽

Grain Yield ◽

Central Africa ◽

Striga Hermonthica ◽

Maize Cultivars ◽

Maize Populations ◽

Striga Resistance ◽

Early Maturing ◽

West And Central Africa ◽

N Rates

SUMMARYBreeding for resistance to Striga hermonthica Del. (Benth) and tolerance to drought has been a major strategy to improve maize (Zea mays L.) production and productivity in West and Central Africa during the last three decades. The three decades consisted of three breeding periods or eras based on the germplasm and methodologies used; that is, 1988–2000, 2001–06 and 2007–11. A total of 50 early maturing cultivars, combining Striga resistance with drought tolerance were developed, including 15, 16 and 19 cultivars for the three periods, respectively. Although the cultivars were not selected intentionally for low-nitrogen (N) tolerance, it was hypothesized that tolerance to low-N had been significantly improved while selecting for drought tolerance and Striga resistance. This hypothesis was tested by evaluating the 50 cultivars in 2010 and 2011 in Nigeria at Mokwa and Ile-Ife under both low-N (30 kg N/ha) and high-N (90 kg N/ha) levels. Under low-N conditions, grain yield improved from 2280 kg/ha during the first period to 2610 kg/ha during the third period, an increase of 165 kg/ha per period with r2 of 0·99. Under high-N, yield increased from 3200 to 3650 kg/ha, an increase of 225 kg/ha and r2 of 0·93. Relative gain per period was 30 kg/ha for the two N rates with r2 values of 0·99 and 0·94 respectively. Grain yield performance of the 50 cultivars under low-N conditions adequately predicted their performance under high-N. Selection for Striga resistance and drought tolerance in early maturing maize populations enhanced low-N tolerance in the maize cultivars derived from the populations. The improvement was higher in later than earlier breeding periods.

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Progress in Breeding Early Maturing Peanut Cultivars with Resistance to Groundnut Rosette Disease in West Africa

Peanut Science ◽

10.3146/pnut.29.1.0004 ◽

2002 ◽

Vol 29 (1) ◽

pp. 17-23 ◽

Cited By ~ 3

Author(s):

B. R. Ntare ◽

P. E. Olorunju ◽

G. L. Hildebrand

Keyword(s):

Virus Disease ◽

Central Africa ◽

Management Program ◽

Sub Saharan Africa ◽

Yield Potential ◽

Breeding Lines ◽

Growing Seasons ◽

Early Maturing ◽

West And Central Africa ◽

Sub Saharan

Abstract Rosette is the most destructive virus disease of peanut (Arachis hypogaea L.) in Sub-Saharan Africa. Resistant cultivars have the greatest potential for minimizing the risk of losses due to the disease. The objectives of this study were to develop and evaluate new peanut breeding lines for reaction to rosette disease and determine their yield potential. Rosette-resistant parents were crossed with early maturing susceptible spanish types. The F2, F4, and F5 generations were grown in a rosette disease screening nursery. A modified bulk-pedigree method was followed in which the populations were grown in bulk until F4. Single plant selections were made in F4-derived F5 progenies. Yield assessment began with F7 lines from 1996 to 1998 growing seasons at three sites. High yielding rosette resistant lines with a maturity range of 90 to 115 d were identified. Some of these new lines produced pod yields significantly higher than the previously developed resistance varieties. Promising lines have been made available to researchers in West and Central Africa and should contribute to an integrated rosette disease management program.

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Gains in Genetic Enhancement of Early Maturing Maize Hybrids Developed during Three Breeding Periods under Striga-Infested and Striga-Free Environments

Agronomy ◽

10.3390/agronomy10081188 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1188

Author(s):

Baffour Badu-Apraku ◽

Gloria B. Adu ◽

Abdoul-Madjidou Yacoubou ◽

Johnson Toyinbo ◽

Samuel Adewale

Keyword(s):

Grain Yield ◽

Central Africa ◽

Striga Hermonthica ◽

Genetic Enhancement ◽

Maize Production ◽

Maize Hybrids ◽

Early Maturing ◽

Yield Gain ◽

West And Central Africa ◽

Damage Number

Striga hermonthica is a major maize production constraint in West and Central Africa (WCA). Fifty-four early maturing maize hybrids of three breeding periods: 2008–2011, 2012–2013, 2014–2015, were evaluated under Striga-infested and non-infested environments in WCA. The study aimed at assessing genetic improvement in grain yield of the hybrids, identifying traits associated with yield gain during the breeding periods, and grain yield and stability of the hybrids in Striga infested and non-infested environments. Annual increase in grain yield of 101 kg ha−1 (4.82 %) and 61 kg ha−1 (1.24%) were recorded in Striga-infested and non-infested environments, respectively. The gains in grain yield from period 1 to period 3 under Striga-infested environments were associated with reduced anthesis-silking interval, reduced Striga damage, number of emerged Striga plants, improved ear aspect, and increased ears per plant. Ear aspect, ears per plant, and Striga damage at 8 and 10 weeks after planting (WAP) were significantly correlated with yield in Striga-infested environments, whereas ears per plant and plant and ear aspects had significant correlations with yield in non-infested environments. Hybrids TZdEI 352 × TZEI 355, TZdEI 378 × TZdEI 173, and TZdEI 173 × TZdEI 352 were outstanding in grain yield and stability in Striga-infested environments, whereas TZEI 326 × TZdEI 352, TZEI 495 × ENT 13, and TZdEI 268 × TZdEI 131 were superior in non-stress environments. These hybrids should be further tested extensively and commercialized. Significant genetic gains have been made in breeding for resistance to Striga hermonthica in early maturing maize hybrids.

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