Genetic variation in root development responses to salt stresses of quinoa

Soil salinity has become a serious environmental abiotic stress limiting crop productivity and quality. The root system is the first organ sensing the changes in salinity. Root development under elevated salinity is therefore an important indicator for saline tolerance in plants. Previous studies focused on varietal differences in morphological traits of quinoa under saline stresses; however, variation in root development responses to salinity remains largely unknown. To understand the genetic variation in root development responses to salt stress of quinoa, we conducted a preliminary screening for salinity response at two salinity levels of a diverse set of 52 quinoa genotypes and microsatellite markers were used to link molecular variation to that in root development responses to salt stresses of represented genotypes. The frequency distribution of saline tolerance index showed continuous variation in the quinoa collection. Cluster analysis of salinity responses divided the 52 quinoa genotypes into six major groups. Based on these results, six genotypes representative of groups I to VI including Black quinoa, 2-Want, Atlas, Riobamba, NL-6 and Sayaña, respectively, were selected to evaluate root development under four saline stress levels: 0, 100, 200 and 300 mM NaCl. Contrasts in root development responses to saline stress levels were observed in the six genotypes. At 100 mM NaCl, significant differences were not observed in root length development (RLD) and root surface development (RSAD) of most genotypes except Black quinoa; a significant reduction was observed in this genotype as compared to controls. At 200 mM NaCl, significant reduction was detected in RLD and RSAD in all genotypes showing this as the best concentration to discriminate among genotypes. The strongest inhibition of root development was found for all genotypes at 300 mM NaCl as compared to lower saline levels. Among genotypes, Atlas of group III shows as a saline-tolerant genotype confirming previous reports. Variation in root responses to salinity stresses is also discussed in relation to climate conditions of origins of the genotypes and reveal interesting guidelines for further studies exploring the mechanisms behind this aspect of saline adaptation.     

有机肥对土壤特性及农产品产量和品质影响研究进展

施用有机肥是农业生产的重要措施,对绿色农业发展起到积极作用,而且越来越广泛施用。本文介绍了目前有机肥基本概况,重点综述了有机肥对提高土壤肥力、提高作物产量和品质、促进养分利用以及对病虫害发生影响等方面研究的最新进展,分析了当前有机肥施用对耕地质量和农产品安全风险、施肥效率低、以及有机肥品种研发不足、相关质量标准滞后等问题,并对当前有机肥推广应用的形势和发展前景进行了分析和展望。     

鱼腥草系列食品开发及其接受度评价

以新鲜鱼腥草为主要原料,设计开发鱼腥草辣椒酱、鱼腥草袋泡茶、鱼腥草饮料和鱼腥草纤维蛋糕四种鱼腥草系列加工食品,通过感官评价分析每个产品的风味特点和人群接受度。结果表明,鱼腥草搭配其他配料可以加工成酱、茶、饮料和蛋糕等产品,四个鱼腥草系列加工食品的风味各有特点,其中鱼腥草豆豉辣椒酱和鱼腥草粗纤维蛋糕的接受度较高。通过添加配料改善鱼腥草产品的风味,不但保留了鱼腥草的味道,而且使不喜食鲜鱼腥草的人群可以接受其加工型产品。     

基于数据包络分析模型下的食用菌产业发展策略

为了科学评价食用菌产业发展策略的有效性,建立了食用菌产业发展策略DEA效率评价指标体系,以食用菌产业发展策略中的一系列投入型策略作为输入指标,以食用菌企业的规模、消费者满意度、科技创新能力和市场竞争力等各种产出效益和效果作为输出指标,采用DEA评价方法对食用菌产业的发展策略的效率进行模拟评价。评价结果显示,对食用菌发展策略产生影响的各种因素是有效的,结果也为为食用菌发展策略的资源投入方向和数量提供了参考。     

2000年以来中国苹果产业发展趋势分析

对2000年以来我国苹果生产、消费和贸易情况进行分析发现,我国苹果生产区域布局较为稳定,生产高度集中于苹果生产优势区域。苹果生产效率大幅提升,不断满足城乡居民对苹果的消费需求,城乡差距不断缩小,苹果产品贸易顺差进一步扩大。但苹果生产成本利润率显著下降,消费者对苹果品质及营养也提出了更高的要求,苹果生产面临成本、质量等方面的挑战。与此同时,苹果生产中技术服务、农业保险等社会化服务也有了初步发展,未来苹果生产将进一步向高效、优质、社会化发展。     

山羊卵泡发育相关基因的筛选及分析

【背景】山羊第一卵泡波中的优势卵泡（dominant follicles, DF）和从属卵泡（subordinate follicles, SF）是整个卵泡发育过程中最为关键的两个阶段。随着卵泡的进一步发育,最终DF可能发育成为成熟卵泡,直到排卵;SF将走向闭锁,其中颗粒细胞的凋亡是导致卵泡发生闭锁的关键因素。然而目前对促进卵泡的优势化或导致其闭锁的分子机理尚不清楚。【目的】通过对山羊第一卵泡波中DF和SF颗粒细胞进行高通量测序,旨在筛选影响卵泡发育的关键基因,为深入探究卵泡发育的调控机制提供理论依据。【方法】选取10只1岁龄健康的贵州白山羊分别注射前列腺素F_2α,使其同期发情,此后每天用B超检测并记录卵泡的生长情况,发情3 d后,统一屠宰并采集第一卵泡波中DF (直径4.5—6 mm)与SF (直径3 —4.5 mm),分别分离其中的颗粒细胞,提取总RNA、构建文库后通过Illumina Hiseq 2500平台进行测序。利用FastQC对测序产出raw reads进行质量评估并经过过滤后,获得品质较高的clean reads;使用Trinity对得到的clean reads进行重新组装,从而获得unigenes;使用CLC Genomics Workbench将unigenes与山羊RefSeq数据库进行比对获得mRNA;使用DESeq2 软件对获得的mRNA进行差异表达分析;分别采用goseq和kobas软件对得到的差异表达基因进行GO分析及KEGG信号通路分析;最终通过qRT-PCR对筛选出的可能影响卵泡发育的关键基因进行验证。【结果】分别对测序得到的raw reads进行过滤后,在DF颗粒细胞中获得43 217 934条clean reads,占raw reads的比例为95.19%;SF颗粒细胞中获得40 766 348条clean reads,占raw reads的比例为95.35%。将得到的unigenes与山羊的RefSeq 数据库进行比对后,共得到33 896条带有注释的转录本,再通过设定FPKM>1, q value<0.05,共在两种卵泡颗粒细胞中获得13 644个基因。设定参数：FPKM≥1,SF-FPKM/DF-FPKM>1,P<0.05,获得695个差异表达mRNA,其中233个在SF颗粒细胞中表达显著上调,462个表达显著下调;对所获得695个差异表达mRNA进行GO功能富集分析,共分为三大类42组：其中生物学过程占47.6%,细胞组分占47.6%,分子功能占4.8%;KEGG信号通路分析,发现20条通路,其中与核糖体通路相关的基因富集最为显著。通过在Genecard中进行功能分析后,筛选6个可能与山羊卵泡发育密切相关的基因,其中PRLR、PTX3、RGN在SF颗粒细胞中表现为上调;DKK3、ALDH1A2、RARRES1则表现为下调。qRT-PCR显示PRLR、RGN、DKK3、ALDH1A2、RARRES1的表达趋势与高通量测序结果一致,且RGN在从属卵泡颗粒细胞中的表达量极显著地高于优势卵泡（P<0.01）;DKK3、ALDH1A2、RARRES1在优势卵泡颗粒细胞中的表达量极显著地高于从属卵泡（P<0.01）。【结论】DKK3、ALDH1A2、RARRES1和RGN在优势卵泡和从属卵泡中表达量存在极显著差异,推测在山羊卵泡发育过程中可能促进卵泡的优势化或导致闭锁,对深入探究卵泡发育的调控机制具有重要意义。     

Regional inequality: An analysis under the core–peripheral model

Desmet, Gumpert, and Ort?n have analyzed regional development using the Ricardian model or the Heckscher–Ohlin theorem. However, aspects such as consideration of combined wages, substitution elasticities, marginal costs, fixed costs, and number of companies were completely ignored. This study investigates the underdevelopment of regions in light of Krugman`s core–peripheral model. The extension of the model is intended to analyze the aspects that have so far been ignored and their influence on the benefits of the two regions. The following aspects characterize the model. Two regions with two sectors are considered for the model. The regions are characterized by different technological equipment. The first region is industrial. The second region has an agricultural character. When a new technology is available, both regions can benefit under certain conditions. The financial transfers lead to a convergence of wages.     

Resettling,disconnecting or displacing? Attending to local sociality,culture and history in disaster settings

In many disaster settings, top‐down responses emphasise ‘expert‐led’ solutions that often involve relocating disaster‐affected communities. While the intention might be to move people from harm's way and facilitate recovery, failure to attend to local pre‐disaster circumstances as well as the interplay between power, resilience and vulnerability within and around affected communities often sees resettlement reconfigure as displacement or disconnection. This oversight may even usher in a new phase of dispossession and disadvantage for marginalised groups (particularly in colonial settings). This paper explores experiences in Australia, Japan and Taiwan to reflect on what issues of local sociality, local culture and local resilience need to be attended to in framing ‘better’ disaster responses.     

竹花叶病毒浙江麻竹分离物全基因组序列及siRNA分析

正已知有3种病毒可在自然条件下侵染竹类植物,即竹花叶病毒(bamboo mosaic virus,BaMV)~[1]、樱桃坏死锈斑驳病毒(cherry necrotic rusty mottle virus,CNRMV)和苹果茎沟病毒(apple stem grooving virus,ASGV)~[2,3]。其中,BaMV是最早在巴西的金竹(Bambusa vulgaris Cv.)和孝顺竹     

基于形态学及多基因位点的枸杞褐斑病病原鉴定

枸杞Lycium barbarum Mill.是一种药食两用的名贵中药材,褐斑病是2010年在甘肃省枸杞种植区发生的由无性态类真菌新种枸杞小黑梨孢Stigmella lycii引起的新病害,据2015年-2018年调查,该病害已扩展至甘肃省各枸杞种植区,常年发病率45%～65%,严重度2～3级。本研究首次对枸杞小黑梨孢有性态形态进行描述,并结合分子生物学方法,确定该病病原菌的系统发育地位,为该病的防治提供一定的理论依据。枸杞褐斑病菌在离体培养条件下和越冬病叶上均可形成有性态。子囊壳球形至亚球形,大小185.6μm×176.6μm,有喙,喙的大小为(35.7～53.6)μm×(32.0～53.55)μm;子囊袋状,大小(103.2～165.7)μm×(15.7～22.4)μm,含8个子囊孢子;子囊孢子砖格状,大小(25.9～36.5)μm×(9.4～14.1)μm,平均31.2μm×12.3μm,具(4～)6～7个纵隔和1～3个横隔。通过ITS、LSU、RPB2和EF1-α多基因位点联合构建系统发育树,确定该菌为子囊菌门格孢腔菌目格孢腔菌科真菌。秋末冬初清洁田园,减少来年初侵染源,是有效防治枸杞褐斑病的关键措施。