Effects of Fertility and Density on Biomass Production,Translocation and Lodging Resistance of Millet(Setaria italica L.)in North China

In this study, the plant biomass production, biomass translocation rates across tissues and the lodging resistant-associated traits of millet （ Setaria italica L.） in North China were investigated. Among the four summer millet cultivars, Baogu 19 exhibited improved plant biomass （PB） production at flowering and maturity stages, biomass translocation amount （BTA） from vegetative tissues to seeds during filling period, and lodging resistant-associated （LRA） traits compared with other cultivars, including enhanced stem lignin contents, increased anti-broken resistance （ABR）, anti-puncturing resistance （APR）, and stem diameter （SD） of plants. Compared with treatment regular cultivation （RC）, high fertility treatment （HF） increased the plant BP, BTA from vegetative tissue to seed at filling stage, and the plant LRA traits; whereas high density treatment （HD） decreased the plant BP at plant level, plant BTA from vegetative tissues to seeds at filling stage, and the plant LRA traits. Correlation analysis revealed that stem ABR is significantly correlated with the plant lodging resistant-associated traits including APR and SD in the summer millet cultivars examined under various cultivation treatments. Our investigation indicates that cultivar Baogu 19 together with suitable fertilization and density can promote the plant biomass production, enhance vegetative tissue biomass translocation to seeds, and improve the lodging resistance of summer millet plants in North China.

Effects of Biogas Slurry Recirculation on Anaerobic Digestion Performance of Maize Straw Silage

In order to investigate the effects of slurry recirculation technology on anaerobic digestion performance of maize straw silage,maize straw silage was fermented with recirculated biogas slurry,and the gas production,p H value,methane content,volatile organic acids( VFAs)contents,chemical oxygen demand( COD) removal rate and other indicators were studied. The results showed that the fermentation time was positively correlated with daily gas production,methane content,cumulative gas production,VFAs and COD removal rate. Although the p H value fluctuated,it was still in the normal reaction range. The daily gas production was about 1. 26 L. The acetic acid content increased first,then decreased,then increased,and finally stabilized. The biogas slurry recirculation technology saves water resources by 40 m L/d without affecting the normal gas production of anaerobic fermentation,and reduces the consumption of environmental resources. It has important development significance for the sustainable use of biomass resources.

Effects of Nitrogen Amount on the Photosynthesis Parameters of Summer Millet in North China

In this study,effects of nitrogen（ N） amount applied on photosynthesis behaviors of the summer millet in North China was investigated. Photosynthetic rates（ Pn）,chlorophyll contents（ Chl）,photosynthetic active duration（ PAD）,and chlorophyll relative steady phase（ RSP） in flag and the upper third leaves were assessed in cultivars of Baogu 19,Jigu 19,9050,and 60 D under three N treatments [i. e.,0（ control）,75,and 150 kg/hm2]. Results indicated that the photosynthesis parameters were drastically regulated by external N levels,all of them showing elevation along with the increased N input in both assayed leaves.Among the cultivars examined,behaviors of the photosynthetic parameters were much better in Baogu 19 and worse in 60 D. The plant yields in the cultivars under various N treatments were shown to be in consistent with the behavior of the photosynthesis parameters. Correlation analysis revealed that plant yield is positively correlated with Pn and Chl and significantly positively correlated with PAD and RSP,suggesting that longer effective photosynthetic duration of leaves impacts largely on plant biomass production and the yield formation potential. Our investigation indicates that suitable external N applied can increase the yield of summer millet associating with the improvement of photosynthesis behaviors in upper leaves that contribute to plant biomass at the late growth stage. Baogu 19 exhibited higher plant yield together with improved photosynthetic parameters in upper leaves,suggesting its potential as an elite cultivar in planting in the summer season of North China.

氨基酸生产的代谢工程研究进展与发展趋势

氨基酸发酵是我国发酵工业的支柱产业,近年来,随着代谢工程的快速发展,氨基酸的代谢工程育种蓬勃发展。传统的正向代谢工程、基于组学分析与计算机模拟的反向代谢工程以及借鉴自然进化的进化代谢工程,都有越来越多的应用。在氨基酸的工业生产中涌现出了一系列具有高效生产、抗逆性强等优良性状的菌株。日益剧烈的市场竞争对菌株的选育提出了新的要求,如开发高附加值氨基酸品种、菌株代谢的动态调控、适应新工艺的要求等。文中介绍了氨基酸生产相关的代谢工程研究进展以及未来的发展趋势。

双金属MOF衍生的Ru掺杂Cu基电催化材料在碱性介质中的高效析氢性能

合理设计和制备廉价且高效的电催化析氢(HER)材料对电解水有着十分重要的意义.本文开发了一种通过热解基于Ru离子交换方法得到的双金属Ru-Cu-BTC金属有机骨架简易制备Ru掺杂Cu负载的多孔碳材料(Ru-Cu@C)的方法.该催化剂在碱性电解液中表现出了优异的HER性能,电流密度为10 mA cm^(-2)时的过电位低至20 mV,且Tafel斜率仅有37 mV dec^(-1),该性能甚至超越了商用Pt/C催化剂.同时,密度泛函理论计算(DFT)结果表明,在Cu纳米晶的晶格中引入Ru原子后,H_(2)的吸附能接近于零,这极大地促进了H2在催化剂表面的脱附,显著改善了HER性能.该策略为开发廉价高效的碱性HER电催化剂提供了新的思路.