Classifying highland quality protein maize in bred lines into heterotic groups

AbstractEarly-maturing provitamin A (PVA) quality protein maize (QPM) hybrids with combined drought and low soil nitrogen (low-N) tolerance are needed to address malnutrition and food security problems in sub-Saharan Africa (SSA). The current study's objectives were to (i) examine combining ability of selected early maturing PVA-QPM inbreds for grain yield and other agronomic traits under drought, low-N, optimal environments and across environments, (ii) determine gene action conditioning PVA accumulation under optimal environments, (iii) classify inbreds into heterotic groups and identify testers and (iv) assess yield and stability of hybrids across environments. Ninety-six hybrids generated from 24 inbred lines using the North Carolina Design II together with four commercial hybrid controls were evaluated under drought, low-N and optimal environments in Nigeria in 2016 and 2017. Fifty-four selected hybrids were assayed for PVA carotenoid and tryptophan content. Additive genetic effects were greater than non-additive effects for grain yield and most agronomic traits under each and across environments. The gene action conditioning accumulation of PVA carotenoids under optimal growing conditions followed a pattern similar to that of grain yield and other yield-related traits. The inbred lines were categorized into four heterotic groups consistent with the pedigree records and with TZEIORQ 29 identified as the best male and female tester for heterotic group IV. No tester was found for the other groups. Hybrid TZEIORQ 24 × TZEIORQ 41 was the highest yielding and most stable across environments and should be further tested for consistent performance for commercialization in SSA.

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PRELIMINARY STUDY ON THE HETEROTIC PATTERN OF TROPICAL QUALITY PROTEIN MAIZE (QPM) AND DOWNY MILDEW RESISTANCE (DMR) MAIZE INBREDS

Zuriat ◽

10.24198/zuriat.v16i2.6761 ◽

2015 ◽

Vol 16 (2) ◽

Author(s):

D. Ruswandi

Keyword(s):

Small Group ◽

Downy Mildew ◽

Major Group ◽

Annual Rainfall ◽

Quality Protein Maize ◽

Downy Mildew Resistance ◽

Heterotic Groups ◽

Mildew Resistance ◽

Preliminary Study ◽

Maize Inbreds

Exploration of heterotic patterns among maize inbreds has become important since it could provide information on which new germplasm could be used to improve base population in breeding program. This experiment was a preliminary study on the heterotic relationships between tropical quality protein maize (QPM) and downy mildew resistance (DMR) maize inbreds based on analysis on combining ability. Seven tropical maize inbreds were crossed in a line × tester. One commercial hybrid from Bisi Company, Bisi 2, was included for the evaluation of hybrids as check cultivar. The result revealed that two heterotic groups has been recognized, i.e., major group consisted of CML 161, CML 163, CML 172, Nei 9008, and P345. Whereas the small group contains MR 10 and Ki 3. The hybrids and their parental inbreds were evaluated in Jatinangor, Indonesia (753 m above sea level) in 2003 to 2004. The location of yield test has a humid climate with an annual rainfall of about 1925 mm. The field experiment was arranged in a randomize block design with two replications. The present study revealed two heterotic groups: major group involving CML 161, CML 163, CML 172, Nei 9008, and Ki 3; and small group containing MR 10 and P 345. Moreover, the major group can be divided into two subgroups involving all CML lines for the first subgroup and Nei 9008 and Ki 3 for the second subgroup.

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Gene Action and Heterotic Groups of Early White Quality Protein Maize Inbreds under Multiple Stress Environments

Crop Science ◽

10.2135/cropsci2015.05.0276 ◽

2016 ◽

Vol 56 (1) ◽

pp. 183-199 ◽

Cited By ~ 25

Author(s):

B. Badu-Apraku ◽

M.A.B. Fakorede ◽

A.O. Talabi ◽

M. Oyekunle ◽

I.C Akaogu ◽

...

Keyword(s):

Gene Action ◽

Quality Protein Maize ◽

Heterotic Groups ◽

Multiple Stress ◽

Maize Inbreds ◽

Stress Environments

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Characterization of the Genetic Diversity Present in a Diverse Sesame Landrace Collection Based on Phenotypic Traits and EST-SSR Markers Coupled With an HRM Analysis

Plants ◽

10.3390/plants10040656 ◽

2021 ◽

Vol 10 (4) ◽

pp. 656

Author(s):

Evangelia Stavridou ◽

Georgios Lagiotis ◽

Parthena Kalaitzidou ◽

Ioannis Grigoriadis ◽

Irini Bosmali ◽

...

Keyword(s):

Ssr Markers ◽

Geographical Origin ◽

Expressed Sequence Tag ◽

Phenotypic Diversity ◽

Molecular Data ◽

Phenotypic Traits ◽

Dissimilarity Matrix ◽

Heterotic Groups ◽

Hrm Analysis ◽

Sesame Genotypes

A selection of sesame (Sesamum indicum L.) landraces of different eco-geographical origin and breeding history have been characterized using 28 qualitative morpho-physiological descriptors and seven expressed sequence tag-simple sequence repeat (EST-SSR) markers coupled with a high-resolution melting (HRM) analysis. The most variable qualitative traits that could efficiently discriminate landraces, as revealed by the correlation analyses, were the plant growth type and position of the branches, leaf blade width, stem pubescence, flowering initiation, capsule traits and seed coat texture. The agglomerative hierarchical clustering analysis based on a dissimilarity matrix highlighted three main groups among the sesame landraces. An EST-SSR marker analysis revealed an average polymorphism information content (PIC) value of 0.82, which indicated that the selected markers were highly polymorphic. A principal coordinate analysis and dendrogram reconstruction based on the molecular data classified the sesame genotypes into four major clades. Both the morpho-physiological and molecular analyses showed that landraces from the same geographical origin were not always grouped in the same cluster, forming heterotic groups; however, clustering patterns were observed for the Greek landraces. The selective breeding of such traits could be employed to unlock the bottleneck of local phenotypic diversity and create new cultivars with desirable traits.

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