Genetic mapping of male sterility and pollen fertility QTLs in triticale with sterilizing Triticum timopheevii cytoplasm

Marzena Wasiak,Piotr Tomasz Bednarek,Mirosław Pojmaj,Henryk Woś,Agnieszka Niedziela

doi:10.1007/s13353-020-00595-z

Abstract

Cytoplasmic male sterility (CMS) phenomenon is widely exploited in commercial hybrid seed production in economically important crop species, including rye, wheat, maize, rice, sorghum, cotton, sugar beets, and many vegetables. Although some commercial successes, little is known about QTLs responsible for the trait in case of triticale with sterilizing Triticum timopheevii (Tt) cytoplasm. Recombinant inbred line (RIL) F6 mapping population encompassing 182 individuals derived from the cross of individual plants representing the HT352 line and cv Borwo was employed for genetic map construction using SNP markers and identification of QTLs conferring pollen sterility in triticale with CMS Tt. The phenotypes of the F1 lines resulting from crossing of the HT352 (Tt) with HT352 (maintainer) × Borwo were determined by assessing the number of the F2 seeds per spike. A genetic map with 21 linkage groups encompasses 29,737 markers and spanned over the distance of 2549 cM. Composite (CIM) and multiple (MIM) interval mappings delivered comparable results. Single QTLs mapped to the 1A, 1B, 2A, 2R, 3B, 3R, 4B, and 5B chromosomes, whereas the 5R and 6B chromosomes shared 3 and 2 QTLs, respectively. The QTLs with the highest LOD score mapped to the 5R, 3R, 1B, and 4B chromosomes; however, the QRft-5R.3 has the highest explained variance of the trait.

Highlights

Triticale (x Triticosecale Wittmack) is a relatively young synthetic species created by hybridization of wheat and rye nearly 150 years ago (Wilson 1875), but it took 100 years until the first variety was released (Kiss 1971)
Many questions concerning, i.e. the genetic pool of the species, the presence of heterotic groups that could be exploited in breeding programs, development of the genetic maps dedicated for dissection of pollen sterility QTLs in triticale with Cytoplasmic male sterility (CMS) the HT352 (Tt) and evaluation of markers useful for breeding programs need to be assessed
Phenotyping of the F1 progeny of the HT352 (Tt) × Recombinant inbred line (RIL) F6: (HT352 (N) × Borwo) showed that varying numbers of seeds were present in each of the lines (Supplementary File 1)

Summary

Introduction

Triticale (x Triticosecale Wittmack) is a relatively young synthetic species created by hybridization of wheat and rye nearly 150 years ago (Wilson 1875), but it took 100 years until the first variety was released (Kiss 1971). Key message Identifying QTLs of male sterility and pollen fertility on a map derived from advanced plant materials created especially for this research. Breeding Department Laski, Danko Plant Breeding Company-Choryń, Laski, Poland grain quality and productivity typical for wheat with vigour, hardiness, disease resistance and high lysine content specific for rye (Myer and Barnett 2000). The development of efficient cytoplasmic male sterility system based on, i.e. CMS Tt, and introducing new triticale hybrid varieties would further stimulate the interest in breeding the species. Many questions concerning, i.e. the genetic pool of the species, the presence of heterotic groups that could be exploited in breeding programs, development of the genetic maps dedicated for dissection of pollen sterility QTLs in triticale with CMS Tt and evaluation of markers useful for breeding programs need to be assessed

Objectives

Methods

Results

Conclusion