Effects of Soil Testing and Formulated Fertilization on Yield and Economic Benefit of Major Crops in Burundi

[Objectives]The purpose of this study was to provide technical support for high-yield cultivation of major crops in Burundi,thereby increasing local farmers'income and promoting sustainable development of agriculture in Burundi.[Methods]In the IMBO and MOSO test stations of the Burundi Academy of Agricultural Sciences and the Burundi Fruit and Vegetable Extension and Service Center,soil testing and formulated fertilization test and demonstration was carried out in rice,maize and cabbage.The test set up three treatments,soil testing and formulated fertilization(STFF),local routine fertilization(RF)and non-fertilization(CK)to investigate the effects of soil testing and formulated fertilization on the yield and economic benefit of the crops.[Results]In the plot test,the yield and net economic benefit of rice,maize and cabbage were both highest in the STFF treatment.Compared with those in the RF treatment,the yield of rice,maize and cabbage increased by 19.0%,25.7%and 33.0%,respectively,and the net economic benefit increased by 4292,2837 and 8232 yuan/ha,respectively.In the field test,the yield and net economic benefit of rice,maize and cabbage were also both highest in the STFF treatment.The yield increased by 18.1%,24.3%and 25.9%,respectively,and the net economic benefit increased by 4142,2881 and 8665 yuan/ha,respectively compared with those in the RF treatment.[Conclusions]Soil testing and formulated fertilization not only increased rice,maize and cabbage yield per unit area,but also increased farmers'income in Burundi.It is one of the important technical measures to promote the increase of agricultural production and income in Burundi.

Validation of the Red Pericarp Gene from 419 Rice Landraces in Guangxi via Genome-wide Association Studies

Rice has different colors of pericarp, such as red, white and black. Red rice pericarp is rich in proanthocyanins, which have antioxidant properties and are beneficial to human health. In the present study, we analyzed the red-pericarp gene Rc of 419 rice landraces in Guangxi by genome-wide association study （GWAS）, and validated that the Rc gene regulated the red periearp trait in flee. By analyzing the genomie DNA of 97 red-pericarp flee eultivars, we identified two new alleles in C139 and C323. Then, the exons of Rcc＇9 and Rcc were sequenced with Sanger method, and the results demonstrated that the natural mutations within Re ene resulted in the two alleles Rcc and Rcc.

Adaptability Evaluation and Annual Production Model of Chinese Vegetable Varieties in Burundi

Burundi is one of the least developed countries identified by the United Nations.Vegetable is the main crop in Burundi,but the variety is relatively simple and the planting level is low.Making use of the rich vegetable varieties and advanced cultivation techniques in China,the adaptability evaluation of new vegetable varieties in China was jointly carried out in Burundi to screen the vegetable varieties suitable for local cultivation.The purpose of this paper is to study the integration of high-yield cultivation techniques and annual production model to improve the level of vegetable cultivation in Burundi.From 2009 to 2015,our unit,together with the Burundian Fruit and Vegetable Promotion Center,carried out screening experiments on 144 vegetable varieties,such as tomato,balsam pear,chieh-qua,wax gourd,and cabbage.Through the methods of preliminary screening and experimental screening,the vegetable varieties suitable for planting in Burundi were selected,and the cultivation techniques of some main vegetable varieties were studied.The demonstration new varieties and new techniques were integrated to verify the high-yield cultivation techniques in the field.In 2009,18 varieties suitable for local planting were selected from 96 vegetable varieties.In 2010,40 vegetable varieties were selected for screening test,and 9 varieties suitable for planting in Burundi were selected.In 2011,27 vegetable varieties selected in 2009 and 2010 were further evaluated for adaptability,and 13 vegetable varieties with high yield,strong resistance and good marketability were selected.Among them,there were 5 melon vegetables,3 solanaceous fruit vegetables,1 legume vegetables and 4 leafy vegetables.The cultivation techniques of some vegetable varieties were studied from 2011 to 2012,and the key points of cultivation techniques of chieh-qua and other vegetable varieties were clarified.According to the ecological characteristics of two main vegetable producing areas(the plateau and plain areas of Burundi),six sets of annual production and cropping arrangement plans covering melons,leafy vegetables,solanaceous fruits,beans and other vegetables were put forward,and the annual production model of multiple cropping and three-dimensional cultivation was integrated.From 2014 to 2015,according to the previous test results and market demand,8 vegetable varieties were selected for Burundi to carry out screening experiments.4 varieties with good yield and adaptability were selected for two consecutive years in 2014 and 2015.The integrated demonstration and effect verification of some selected vegetable varieties and cultivation techniques were carried out from 2015 to 2016,and the comprehensive advantages such as field yield and economic benefit were obvious.In this study,the adaptability of Chinese vegetable varieties in Burundi was evaluated,and 17 vegetable varieties suitable for local production were selected,including 5 melon vegetables,5 solanaceous fruit vegetables,1 legume vegetables and 6 leafy vegetables.This paper studies the integrated cultivation techniques and annual production model with obvious advantages in yield and benefit,which plays an important role in improving the planting level and benefit of vegetables in Burundi.

Chaff Jamming Recognition of Radar

A modified chaff jamming recognition method of radar is investigated using grey relational analysis（ GRA） based on the difference in echo correlation characteristics between a complex rigid target and chaff cloud in time domain. Slice method（ SM）,a novel modeling approach,is proposed to construct an electromagnetic scattering model of chaff cloud in a scenario with slowly moving platform that is targeted. The diffusion characteristics and echo characteristics of the chaff cloud are analyzed. The GRA of a real target and chaff cloud shows that the adjacent return waves have a good correlation for the target but a weak correlation for chaff cloud. Since the correlation degree of chaff cloud＇s echo is far lower than that of a complex rigid target＇s,the chaff jamming can be identified by setting a reasonable threshold. Simulation results are presented to verify the effectiveness of this method.

新时期支撑高质量科技创新的科技管理发展路径与对策研究

当前我国深入实施创新驱动发展战略,构建高效、协同、开放的国家创新体系,持续推进科技管理体制机制的深化改革。科技管理的能力和水平,直接影响创新投入和绩效产出,也关乎国家创新驱动发展战略的实施。本文试图结合当前科技发展趋势、国家科技体制改革及科研“放管服”精神的落实,分析当前影响和制约科技管理的现状和主要问题,并提出若干提升科技管理能力的路径与对策,以期推动建立与当前科技发展阶段相适应的高质量科技管理体系。

科学基金改革背景下依托单位保障与监督机制研究

科学基金改革背景下,国家自然科学基金依托单位工作面对“放管服”改革、科研诚信维护、项目成果转化所带来的一系列挑战,存在着数字化转型不足、学术不端行为防范不利、科技成果转化管理贯通机制有待完善等问题。本文结合依托单位基金工作的各个阶段及管理工作实践,提出依托单位保障与监督职责协同拓展对策需要基于科学基金项目管理流程的信息化、科研人员学术生涯的保障科学化、科研项目成果转化的专业化三个方面展开。

Single-cell-resolution transcriptome map revealed novel genes involved in testicular germ cell progression and somatic cells specification in Chinese tongue sole with sex reversal

Female-to-male sex reversals(pseudomales)are common in lower vertebrates and have been found in natural populations,which is a concern under rapid changes in environmental conditions.Pseudomales can exhibit altered spermatogenesis.However,the regulatory mechanisms underlying pseudomale spermatogenesis remain unclear.Here,we characterized spermatogenesis in Chinese tongue sole(Cynoglossus semilaevis),a species with genetic and environmental sex determination,based on a highresolution single-cell RNA-seq atlas of cells derived from the testes of genotypic males and pseudomales.We identified five germ cell types and six somatic cell types and obtained a single-cell atlas of dynamic changes in gene expression during spermatogenesis in Chinese tongue sole,including alterations in pseudomales.We detected decreased levels of Ca^(2+)signaling pathway-related genes in spermatogonia,insufficient meiotic initiation in spermatocytes,and a malfunction of somatic niche cells in pseudomales.However,a cluster of CaSR genes and MAPK signaling factors were upregulated in undifferentiated spermatogonia of pseudomales.Additionally,we revealed that Z chromosome-specific genes,such as piwil2,dhx37,and ehmt1,were important for spermatogenesis.These results improve our understanding of reproduction after female-to-male sex-reversal and provide new insights into the adaptability of reproductive strategies in lower vertebrates.

分子凝胶:从结构调控到功能应用

作为一类典型软物质材料,近年来分子凝胶在生物医学、柔性电子设备、晶体控制生长、水体净化,以及3D打印材料、微纳米材料和高能量密度材料制备等领域表现出巨大的应用潜力,受到人们越来越多的关注。如何提高分子凝胶结构调控效率,拓展分子凝胶功能,促进分子凝胶实际应用已经成为新阶段分子凝胶研究的主要内容。本文结合本课题组的研究工作,从动态共价键调控分子凝胶力学性能、分子凝胶促进高品质有机晶体制备和高性能多孔高分子材料的分子凝胶(凝胶乳液)软膜板制备三个方面阐述分子凝胶的结构调控和功能化应用研究。在此基础上,简要展望分子凝胶研究的发展趋势。

Epitaxial growth of large-area and highly crystalline anisotropic ReSe2 atomic layer

The anisotropic two-dimensional （2D） layered material rhenium disulfide （ReSe2） has attracted considerable attention because of its unusual properties and promising applications in electronic and optoelectronic devices. However, because of its low lattice symmetry and interlayer decoupling, anisotropic growth and out-of-plane growth occur easily, yielding thick flakes, dendritic structure, or flower-like structure. In this stud34 we demonstrated a bottom-up method for the controlled and scalable synthesis of ReSe2 by van der Waals epitaxy. To achieve controllable growth, a micro-reactor with a confined reaction space was constructed by stacking two mica substrates in the chemical vapor deposition system. Within the confined reaction space, the nucleation density and growth rate of ReSe2 were significantly reduced, favoring the large-area synthesis of ReSe2 with a uniform monolayer thickness. The morphological evolution of ReSe2 with growth temperature indicated that the anisotropic growth was suppressed at a low growth temperature （〈600 ℃）. Field-effect transistors employing the grown ReSe2 exhibited p-type conduction with a current ON/OFF ratio up to 10s and a hole carrier mobility of 0.98 cm^2/（V·s）. Furthermore, the ReSe2 device exhibited an outstanding photoresponse to near-infrared light, with responsivity up to 8.4 and 5.1 A/W for 850- and 940-nm light, respectively. This work not only promotes the large-scale application of ReSe2 in high-performance electronic devices but also clarifies the growth mechanism of low-lattice symmetry 2D materials.