Genetic analysis of maize shank length by QTL mapping in three recombinant inbred line populations. (February 2021)

• Record Type: Journal Article
• Authors: Liu, Meiling; He, Wenshu; Zhang, Ao; Zhang, Lijun; Sun, Daqiu; Gao, Yuan; Ni, Pengzun; Ma, Xinglin; Cui, Zhenhai; Ruan, Yanye
• Is Part Of: Plant science. Volume 303(2021)
• Publication Date: 2021-02
• Subjects: SL shank length -- HL husk length -- HN husk number -- HW husk width -- EL ear length -- CW cob weight -- EW ear weight -- ERN ear row number -- PH plant height -- EH ear height -- BJ Beijing -- LN Liaoning -- NM Neimeng -- RIL recombinant inbred line -- BLUP best linear unbiased prediction -- QTL quantitative trait locus -- SNP single nucleotide polymorphisms -- JA jasmonic acid; Maize (Zea mays) -- Shank length -- QTL mapping -- Genetic overlap -- Bin map -- Hormone; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2020.110767
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Shank length is positively correlated with the husk length, husk number, ear length and ear weight, but is negatively correlated with the husk width. Shank length is highly heritable, and 10 quantitative trait loci for shank length were identified in three RIL populations. Five candidate genes for shank length may affect hormone metabolism and sphingolipid biosynthesis to regulate cell elongation, division and so on. Abstract: In maize, the shank is a unique tissue linking the stem to the ear. Shank length (SL) mainly affects the transport of photosynthetic products to the ear and the dehydration of kernels via regulated husk morphology. The limited studies on SL revealed it is a highly heritable quantitative trait controlled by significant additive and additive-dominance effects. However, the genetic basis of SL remains unclear. In this study, we analyzed three maize recombinant inbred line (RIL) populations to elucidate the molecular mechanism underlying the SL. The data indicated the SL varied among the three RIL populations and was highly heritable. Additionally, the SL was positively correlated with the husk length (HL), husk number (HN), ear length (EL), and ear weight (EW) in the BY815/K22 (BYK) and CI7/K22 (CIK) RIL populations, but was negatively correlated with the husk width (HW) in the BYK RIL population. Moreover, 10 quantitative trait loci (QTL) for SL were identified in the three RIL populations, five of which were large-effect QTL. The percentage of the total phenotypic variation explained by the QTL for SL was 13.67 %, 20.45 %, and 30.81 % in the BY815/DE3 (BYD), BYK, and CIK RIL populations, respectively. Further analyses uncovered some genetic overlap between SL and EL, SL and ear row number (ERN), SL and cob weight (CW), and SL and HN. Unlike the large-effect QTL qSL BYK-2−2, which spanned the centromere, the other four large-effect QTL were delimited to a single peak bin via bin map. Furthermore, 2, 5, 6, and 12 genes associated with SL were identified for qSL BYK-2−1, qSL CIK-2−1, qSL CIK-9−1, and qSL CIK-9−2, respectively. Five of the candidate genes for SL may contribute to the hormone metabolism and sphingolipid biosynthesis regulating cell elongation, division, differentiation, and expansion. These results may be relevant for future studies on the genetic basis of SL and for the molecular breeding of maize based on marker-assisted selection to develop new varieties with an ideal SL.