Dissecting the Genetic Basis of Flowering Time and Height Related-Traits Using Two Doubled Haploid Populations in Maize.

Lei Du,Hao Zhang,Dengxiang Du,Yongzhong Liu,Kejun Ma,Changping Yu,Wangsen Xin

doi:10.3390/plants10081585

Abstract

In the field, maize flowering time and height traits are closely linked with yield, planting density, lodging resistance, and grain fill. To explore the genetic basis of flowering time and height traits in maize, we investigated six related traits, namely, days to anthesis (AD), days to silking (SD), the anthesis–silking interval (ASI), plant height (PH), ear height (EH), and the EH/PH ratio (ER) in two locations for two years based on two doubled haploid (DH) populations. Based on the two high-density genetic linkage maps, 12 and 22 quantitative trait loci (QTL) were identified, respectively, for flowering time and height-related traits. Of these, ten QTLs had overlapping confidence intervals between the two populations and were integrated into three consensus QTLs (qFT_YZ1a, qHT_YZ5a, and qHT_YZ7a). Of these, qFT_YZ1a, conferring flowering time, is located at 221.1–277.0 Mb on chromosome 1 and explained 10.0–12.5% of the AD and SD variation, and qHT_YZ5a, conferring height traits, is located at 147.4–217.3 Mb on chromosome 5 and explained 11.6–15.3% of the PH and EH variation. These consensus QTLs, in addition to the other repeatedly detected QTLs, provide useful information for further genetic studies and variety improvements in flowering time and height-related traits.

Highlights

Maize (Zea mays L.) is an important food and forage crop, and an industrial raw material crop
Flowering time and height traits are important agronomical traits in maize production, and are closely linked to the switch from vegetative growth to reproductive growth [1]. The balance of this switch usually breaks down when the breeding process is exposed to an exotic maize germplasm source, especially tropical and subtropical material, which generally leads to late flowering and a greater height [2]
The parent Q1 had a later flowering time and taller height compared with the parents Ye478 and Zheng58

Summary

Introduction

Maize (Zea mays L.) is an important food and forage crop, and an industrial raw material crop. Flowering time and height traits are important agronomical traits in maize production, and are closely linked to the switch from vegetative growth to reproductive growth [1]. The balance of this switch usually breaks down when the breeding process is exposed to an exotic maize germplasm source, especially tropical and subtropical material, which generally leads to late flowering and a greater height [2]. Flowering time and height traits are often among the main issues that must be overcome when using new maize germplasm. Map-based cloning for dissecting quantitative traits and using linked markers for improvement are an effective breeding strategy. Many flowering time-related major QTLs detected by QTL mapping have been proposed, such as epc [6], D8idp [7], zfl1 [8], conz1 [9], ZmPR1-4 [10], ZCN8 [11], and eIF-4A [12]. High-resolution populations and high-density molecular markers have been widely utilized in genetic mapping, and many novel loci for these traits have been found in maize [13,14]

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