Maize (<em>Zea mays</em> L.) as a Model System for Plant Genetic, Genomic, and Applied Research

Maize leads the world’s cereals after wheat and rice in terms of cultivated area, because of its economic importance for the production of both food purposes and raw materials for industry. The maize genus Zea L. belonging to the family of cereals (Poaceae or Graminaceae) includes six species. However, all cultivated maize belongs specifically to Zea mays L. subsp. mays (2n = 2× = 20) is the only cultivated species of the genus Zea L., and the remaining species of this genus are mostly wild herbaceous plants. In addition to meeting the nutritional needs of the world’s population, Zea mays L. is one of the classic model objects of genetic and physiological research, as well as in the field of breeding not only cereals but also other important agricultural plants. Especially, this model object has been used in genetic mapping of loci of quantitative traits and genes associated with economically valuable traits, such as yield, resistance to diseases and pests, grain quality, etc. in cereal crops

Genetic Analysis of Mutagenesis That Induces the Photoperiod Insensitivity of Wild Cotton Gossypium hirsutum Subsp. purpurascens

Cotton genus Gossypium L., especially its wild species, is rich in genetic diversity. However, this valuable genetic resource is barely used in cotton breeding programs. In part, due to photoperiod sensitivities, the genetic diversity of Gossypium remains largely untapped. Herein, we present a genetic analysis of morphological, cytological, and genomic changes from radiation-mediated mutagenesis that induced plant photoperiod insensitivity in the wild cotton of Gossypium hirsutum. Several morphological and agronomical traits were found to be highly inheritable using the progeny between the wild-type G. hirsutum subsp. purpurascens (El-Salvador) and its mutant line (Kupaysin). An analysis of pollen mother cells (PMCs) revealed quadrivalents that had an open ring shape and an adjoining type of divergence of chromosomes from translocation complexes. Using 336 SSR markers and 157 F2 progenies that were grown with parental genotypes and F1 hybrids in long day and short night conditions, five quantitative trait loci (QTLs) associated with cotton flowering were located on chromosomes At-05, At-11, and Dt-07. Nineteen candidate genes related to the flowering traits were suggested through molecular and in silico analysis. The DNA markers associated with the candidate genes, upon future functional analysis, would provide useful tools in marker-assisted selection (MAS) in cotton breeding programs for early flowering and maturity

Genetic variances and estimated broad-sense heritability of traits in the F₃ population.

<p>Genetic variances and estimated broad-sense heritability of traits in the F₃ population.</p

Genetic linkage map of the F₃ population showing the location of QTL for photoperiodic flowering.

<p>Genetic linkage map of the F₃ population showing the location of QTL for photoperiodic flowering.</p

The level of polymorphism of all SSR markers between parental genotypes.

<p>The level of polymorphism of all SSR markers between parental genotypes.</p

The cross-combination between the wild type of cotton species <i>G</i>. <i>darwinii</i> Watt with its photoperiod insensitive irradiation mutant line.

<p>A) Wild type, B) F₁ plant, and C) irradiation mutant line.</p

Linkage group (LG) / chromosome (Chr.) information in the F₂ population.

<p>Linkage group (LG) / chromosome (Chr.) information in the F₂ population.</p