Heterosis plays an important role in crop production and plant evolution. Although heterosis has been widely exploited by plant breeders, the underlying molecular mechanisms are not well understood. We analyzed gene e...Heterosis plays an important role in crop production and plant evolution. Although heterosis has been widely exploited by plant breeders, the underlying molecular mechanisms are not well understood. We analyzed gene expression of the highly heterotic maize hybrid Zhengdan 958 and its parents, Zheng 58 and Chang 7-2 during spikelet and floscule differentiation using the GeneChip Maize Genome Array. Pairwise comparison among Zhengdan 958 and its parents at the two stages of immature ear development identfied 1 089 and 1 352 differentially expressed genes. Gene ontology （GO） functional analysis showed that these genes participate in many functional categories, and those encoding response to stress and transcription factor may play important roles in heterosis. Pathway analysis showed that the differentially expressed genes are involved in various metabolic processes, and those participating in lipid metabolism, signal transduction, transport, and catabolism may contribute to heterosis. A non-additive expression pattern was prevalent in genes that were differentially expressed between the hybrid and its parents during both spikelet and floscule differentiation. Because genes that are differentially expressed in a hybrid and its parents could underlie heterosis, nonadditive expression patterns might contribute to the manifestation of heterosis.展开更多
[Objective] The study is aimed to timely grasp the growth and develop- ment process of summer maize and comprehensively evaluate the impact of envi- ronmental factors on the growth and development of maize in north Hu...[Objective] The study is aimed to timely grasp the growth and develop- ment process of summer maize and comprehensively evaluate the impact of envi- ronmental factors on the growth and development of maize in north Huanguaihai re- gion. [Method] The phenophase, leaf unfolding rate, grain filling rate and yield char- acteristics of Zhengdan 958 and Xianyu 335 were analyzed at N 37°53′, E115°42′. [Result] The summer corn Zhengdan 958 and Xianyu335 emerged in 6 days after sowing with the growing period of 111 d, grain-filling stage lasting 66 days, and the leaf unfolding rate and grain filling rate were accelerated with the increase of tem- perature. In the last 6 d before harvest （October 5-11）, Zhengdan 958 and Xi- anyu335 contributed to the yield by 6.61% and 4.20%, respectively. The two crops a year cropping system made it hard for the summer maize to achieve maturing harvest in north Huanghuaihai region. [Conclusion] The maize production could be significantly improved through selecting early maturing varieties, early sowing, timely late harvest, ensuring maize effective accumulated temperature and sufficient grout- ing time after pollination.展开更多
基金supported by the National High-Tech R&D Program of China (2011AA10A103)the National Basic Research Program of China (2009CB118400)
文摘Heterosis plays an important role in crop production and plant evolution. Although heterosis has been widely exploited by plant breeders, the underlying molecular mechanisms are not well understood. We analyzed gene expression of the highly heterotic maize hybrid Zhengdan 958 and its parents, Zheng 58 and Chang 7-2 during spikelet and floscule differentiation using the GeneChip Maize Genome Array. Pairwise comparison among Zhengdan 958 and its parents at the two stages of immature ear development identfied 1 089 and 1 352 differentially expressed genes. Gene ontology （GO） functional analysis showed that these genes participate in many functional categories, and those encoding response to stress and transcription factor may play important roles in heterosis. Pathway analysis showed that the differentially expressed genes are involved in various metabolic processes, and those participating in lipid metabolism, signal transduction, transport, and catabolism may contribute to heterosis. A non-additive expression pattern was prevalent in genes that were differentially expressed between the hybrid and its parents during both spikelet and floscule differentiation. Because genes that are differentially expressed in a hybrid and its parents could underlie heterosis, nonadditive expression patterns might contribute to the manifestation of heterosis.
基金Supported by the Foundation of China Agricultural Research System for Maize Industry(CARS-02-48)~~
文摘[Objective] The study is aimed to timely grasp the growth and develop- ment process of summer maize and comprehensively evaluate the impact of envi- ronmental factors on the growth and development of maize in north Huanguaihai re- gion. [Method] The phenophase, leaf unfolding rate, grain filling rate and yield char- acteristics of Zhengdan 958 and Xianyu 335 were analyzed at N 37°53′, E115°42′. [Result] The summer corn Zhengdan 958 and Xianyu335 emerged in 6 days after sowing with the growing period of 111 d, grain-filling stage lasting 66 days, and the leaf unfolding rate and grain filling rate were accelerated with the increase of tem- perature. In the last 6 d before harvest （October 5-11）, Zhengdan 958 and Xi- anyu335 contributed to the yield by 6.61% and 4.20%, respectively. The two crops a year cropping system made it hard for the summer maize to achieve maturing harvest in north Huanghuaihai region. [Conclusion] The maize production could be significantly improved through selecting early maturing varieties, early sowing, timely late harvest, ensuring maize effective accumulated temperature and sufficient grout- ing time after pollination.
