Breeding Potential of Exotic Maize Populations to Improve an Elite Chinese Hybrid

Abstract

Introgression of favorable alleles from exotic maize (Zea mays L.) germplasm can broaden the narrow genetic base of available temperate germplasm. Development of maize hybrids for the Yellow and Huai river valleys in the Corn Belt of China has always been hampered by the lack of favorable alleles for improving maize yield and quality. Twenty exotic populations from CIMMYT and the United States were evaluated to identify alleles for improving a widely cultivated hybrid, Zheng 58 × Chang 7‐2, which represents the predominant heterotic group, PA × Sipingtou. Sixty‐three genotypes, comprising 20 populations, two inbred lines (Zheng 58 and Chang 7‐2), a single‐cross hybrid (Zheng 58 × Chang 7‐2), and 40 inbred × population crosses between the parental inbreds and the CIMMYT and U.S. populations were evaluated for grain yield, test weight, and ear height. Several populations from CIMMYT and the United States were identified as potential sources of favorable alleles for traits lacking in the elite hybrid, Zheng 58 × Chang 7‐2, for each trait evaluated. Two exotic populations, Pop 49 and Stay green‐yellow, were the most outstanding because they possessed favorable alleles for several traits that were not present in the target hybrid evaluated. These results demonstrate that the exotic populations evaluated in this study represent sources of useful genetic variability with good potential for improving Chinese elite germplasm.

Gene expression variation explains maize seed germination heterosis

“…Together with its parental inbred lines Zheng58 (maternal line, referred to as Z58 hereafter) and Chang7-2 (paternal line, referred to as C72 hereafter) were utilized for this study. The dent inbred line Z58 was selected from a synthetic population of Chinese domestic germplasm with Reid lineage, and the flint inbred line C72 was selected from the Chinese heterotic group Sipingtou [ 57 ]. In the summer of 2018, the two parental lines were planted on the farm of Henan agricultural university (Zhengzhou, China).…”

Gene Expression Variation Explains Maize Seed Germination Heterosis

“…Together with its parental inbred lines Zheng58 (maternal line, referred to as Z58 hereafter) and Chang7-2 (paternal line, referred to as C72 hereafter) were utilized for this study. The dent inbred line Z58 was selected from a synthetic population of Chinese domestic germplasm with Reid lineage, and the int inbred line C72 was selected from the Chinese heterotic group Sipingtou [56]. In summer of 2018, the two parental lines were planted in farm of Henan agricultural university (Zhengzhou, China).…”

Analysis on breeding potential of eight synthetic populations to improve a Chinese maize hybrid Zhengdan 958

“…Incognito 等 [18] 利用阿根廷地方品种改良青贮玉米杂 交种 B73 × LP122-2 的品质性状。国内对此报道较 少, 雍洪军等 [19] [20] 对每个 性状单独进行方差分析, 采用 Bartlett 法检验方差的 差异性 [21] 。设置环境、重复和区组为随机变量, 品 种为固定变量。通过 PROC MIXED 和 LSMEANS 程序计算各性状联合环境下的校正值 [20] 。 采用 4 个遗传参数评价群体改良杂交种的潜 力。Dudley 提出了从群体向单交种转移有利等位基 因 的 理 论 [ 8 ] , 假 设 任 意 两 个 自 交 系 有 4 类 等 位…”