Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70599 Stuttgart, Germany.
BMC Plant Biol. 2010 Apr 12;10:63. doi: 10.1186/1471-2229-10-63.
The importance of maize for human and animal nutrition, but also as a source for bio-energy is rapidly increasing. Maize yield is a quantitative trait controlled by many genes with small effects, spread throughout the genome. The precise location of the genes and the identity of the gene networks underlying maize grain yield is unknown. The objective of our study was to contribute to the knowledge of these genes and gene networks by transcription profiling with microarrays.
We assessed the grain yield and grain dry matter content (an indicator for early maturity) of 98 maize hybrids in multi-environment field trials. The gene expression in seedlings of the parental inbred lines, which have four different genetic backgrounds, was assessed with genome-scale oligonucleotide arrays. We identified genes associated with grain yield and grain dry matter content using a newly developed two-step correlation approach and found overlapping gene networks for both traits. The underlying metabolic pathways and biological processes were elucidated. Genes involved in sucrose degradation and glycolysis, as well as genes involved in cell expansion and endocycle were found to be associated with grain yield.
Our results indicate that the capability of providing energy and substrates, as well as expanding the cell at the seedling stage, highly influences the grain yield of hybrids. Knowledge of these genes underlying grain yield in maize can contribute to the development of new high yielding varieties.
玉米对人类和动物营养的重要性，以及作为生物能源的来源，其重要性正在迅速增加。玉米产量是由许多基因控制的数量性状，这些基因的效应很小，分布在整个基因组中。这些基因以及控制玉米籽粒产量的基因网络的确切位置尚不清楚。我们的研究目的是通过微阵列转录谱分析来增加对这些基因和基因网络的了解。
我们在多环境田间试验中评估了 98 个玉米杂交种的籽粒产量和籽粒干物质含量（早期成熟的指标）。用基因组规模的寡核苷酸阵列评估了具有四种不同遗传背景的亲本自交系幼苗的基因表达。我们使用新开发的两步相关方法鉴定了与籽粒产量和籽粒干物质含量相关的基因，并找到了与两个性状相关的重叠基因网络。阐明了潜在的代谢途径和生物学过程。与籽粒产量相关的基因涉及蔗糖降解和糖酵解，以及与细胞扩张和内循环相关的基因。
我们的结果表明，在幼苗阶段提供能量和底物的能力以及细胞扩张的能力，极大地影响了杂种的籽粒产量。对玉米籽粒产量相关基因的了解可以为开发新的高产品种做出贡献。
