腐烂葡萄中微生物多样性及真菌毒素测定分析

以天津、北京、杭州等10个地区的葡萄园以及市场中的75份腐烂葡萄为研究对象，应用分子生物学手段进行葡萄表面微生物（细菌和真菌）多样性的核酸测序（包括16S区域扩增子和ITS区域扩增子）分析；同时基于次级代谢产物，使用高效液相色谱（HPLC）法对葡萄样本进行了21种真菌毒素的测定分析，以初步摸清主要风险危害，锁定风险菌株。结果表明，对表面微生物的核酸测序共获得细菌16S有效OTU信息732个和真菌ITS有效OTU信息4 336个，构建了葡萄表面菌相分子数据库，其中包括367种细菌和256种真菌，其主要病原菌为青霉、黑曲、链格孢菌、杂色曲霉、灰葡萄孢、炭疽和盾壳霉；通过真菌毒素测定分析，共检测出4种真菌毒素，分别为交链孢毒素AOH、交链孢毒素AME、交链孢毒素TeA和交链孢毒素TEN。     

放牧强度对草甸草原植物群落特征及营养品质的影响

【目的】 植物群落特征是草地生态系统功能变化的敏感指标,是判别干扰条件下植被退化的重要生态学指标之一。研究不同放牧强度下温性草甸草原植物特征及品质变化情况,以了解放牧作用下草原植物退化的过程和机制,为退化草地生态恢复提供理论依据。【方法】 以呼伦贝尔草甸草原肉牛控制放牧试验为平台,分析6种不同放牧强度（对照区G0.00:0,轻度放牧G0.23:0.2 cow.AU/hm²,较轻度放牧G0.34:0.34 cow.AU/hm²,中度放牧G0.46:0.46 cow.AU/hm²,较重度放牧G0.69:0.69 cow.AU/hm²,重度放牧G0.92:0.92 cow.AU/hm²）下温性草甸草原植物群落数量特征、多样性、功能群与营养品质的变化,并探讨他们之间的相关性。【结果】 放牧强度大于0.34 cow.AU/hm²时,群落盖度、群落高度、群落地上生物量、原有优势植物（羊草(Leymus chinensis))和贝加尔针茅(Stipa baicalensis)）生物量、地下生物量、枯落物生物量均呈现显著降低（P<0.05）,退化指示植物生物量（冷蒿、二裂委陵菜、星毛委陵菜和寸草苔）显著增加（P<0.05）;随着放牧强度的增加,群落α多样性指数呈现先升高后降低的趋势,放牧强度为0.34—0.46 cow.AU/hm²时,草地群落α多样性指数最高,符合中度干扰假说;植物功能群禾本科植物及其优势植物重要值随着放牧强度的增加逐渐降低,当放牧强度大于0.23 cow.AU/hm²时,优势植物重要值显著降低（P<0.05）,莎草科与退化指示植物重要值显著增加（P<0.05）。放牧不同程度增加了植物粗蛋白、粗灰分、总磷、钙和无氮浸出物含量,显著降低了植物粗脂肪、中性洗涤纤维和粗纤维含量（P<0.05）;群落α多样性指数相互之间呈极显著正相关（P<0.01）,与植物功能群豆科植物和杂类草重要值呈显著正相关、与禾本科植物重要值呈负相关;植物功能群禾本科和毛茛科植物重要值与植物酸性洗涤纤维和钙呈显著负相关、与中性洗涤纤维呈显著正相关,莎草科植物重要值与之相反。【结论】 不同放牧强度下植物群落特征及营养品质发生不同程度的变化,放牧强度为0.23—0.34 cow.AU/hm²较为适宜,适度放牧有利于提高群落物种多样性,保持草地植物群落稳定,促进草地生态系统可持续发展。     

刈割干扰对羊草草甸草原植物功能群及多样性的影响

【目的】 刈割是草原主要利用方式之一,植物功能群和群落物种多样性是判别干扰条件下草地生态系统退化的重要生态学指标。研究不同刈割干扰下羊草草甸草原植物功能群和群落物种多样性的变化,了解刈割干扰下草原功能群与多样性变化过程和机制,为退化割草地生态恢复提供理论依据。【方法】 以呼伦贝尔羊草草甸草原时空刈割配置为试验平台,于2014—2018年植物生长最旺盛的季节（即每年8月初）,采用样方法对各个小区进行群落植被调查。分析一年一割（G1）、两年一割（G2）、漏割带10 m（G3）、漏割带5 m（G4）和对照（CK）处理下草甸草原群落功能群和物种多样性变化以及刈割时间和不同刈割处理间的交互作用,探讨植物功能群与群落物种多样性的相关关系。【结果】 研究发现羊草（Leymus chinensis）在不同刈割制度下均为优势物种,但是随着刈割频次的增加呈现出羊草重要值逐渐降低,退化指示物种星毛委陵菜（Potentilla acaulis）、披针叶黄华（Thermopsis lanceolate）等重要值增加的趋势;两年一割处理下羊草、糙隐子草（Cleistogenes squarrosa）、长柱沙参（Adenophora stenanthina）、柴胡（Bupleurum scorzonerifolium）和草地早熟禾（Poa ratensis）等植物重要值均高于其他处理。一年一割和常年不刈割处理下草地植物禾本科和豆科植物重要值所占比例减少,以退化植物居多的菊科和莎草科植物所占比例增加,在漏割带为10 m处理草地的豆科植物增加;刈割处理5年后,不同刈割制度下植物群落物种多样性指数均有增加,其中漏割带为10 m处理Shannon-Wiener多样性和Simpson优势度指数增加明显。5个刈割处理均匀度指数变化趋势不同,其中G3和G4处理草地的群落均匀度有增加的趋势,分别增加16%和5.8%,G1、G2和CK草地群落均匀度指数下降,其中G1下降最大（下降了1.8%）,其次是CK（下降1.6%）,G2草地下降最少。植物群落物种多样性指数变化分析表明经过5年不同刈割处理,漏割带10 m处理的草地植物群落物种多样性提高。群落物种多样性指数与植物功能群禾本科重要值存在极显著负相关关系,与毛茛科和菊科重要值呈现显著正相关关系。【结论】 长期高频度刈割会导致草原退化,同样对草原长期不利用也会致使草原发生逆行演替;两年一割和漏割带为10 m的连年刈割均可以缓解群落中禾本科等优势植物比例下降,促进毛茛科植物比例增加;经过5年的不同刈割处理,漏割带为10 m的刈割处理植物群落物种多样性有所提高,即对草原进行适度刈割干扰（两年一割和漏割带10 m）有利于草原的可持续发展。     

土壤日晒在绿色植保中的应用与展望

土壤消毒主要用于土壤病虫草害防控。过去几十年,土壤主要采用化学药品熏蒸消毒,不合理使用容易造成环境污染。土壤蒸汽消毒、火焰消毒和热水浇灌等需要专门的仪器设备,且存在能耗较高、灭生性强、容易破坏土壤结构等缺点。目前,土壤日晒技术受到意大利、美国、以色列等70多个国家农业科学家的广泛关注,但在中国依然处于初级阶段。本文总结了国内外学者关于土壤日晒对农业病虫草害、土壤肥力、农作物产量等方面的影响与应用,分析了土壤日晒存在的局限性,并对土壤日晒在未来农业绿色防控上的应用前景进行了展望,以期为农产品无公害生产提供理论依据和实践参考。     

Comparison of the microbial communities of alpacas and sheep fed diets with three different ratios of corn stalk to concentrate

The objective of this study was to investigate the characteristics of ruminal microbial communities of alpacas (Lama pacos) and sheep (Ovis aries) fed three diets with varying ratios of roughage (corn stalk) to concentrate, 3:7 (LS), 5:5 (MS) and 7:3 (HS). Six alpacas (one-year-old and weighing 29.5 ± 7.1 kg) and six sheep (one-year-old and weighing 27.9 ± 2.7 kg) were used in this study, in a replicated 3 × 3 Latin square experiment. Total protozoa concentration was determined under the microscope; total fungi and methanogens were assessed using quantitative polymerase chain reaction and expressed as a percentage of total bacterial 16S rRNA gene copies; bacterial communities were investigated by targeted 16S rRNA gene (V3–V4 region) sequencing. The percentage of fungi was significantly higher in alpacas than in sheep under the LS diet, while the concentration of protozoa was significantly lower in alpacas under HS, MS and LS diets. The alpha diversity including Shannon, Chao l and ACE indices of bacterial communities was higher in alpacas than in sheep, under the LS diet. A total of 299 genera belonging to 22 phyla were observed in the forestomach of alpaca and sheep, with Bacteroidetes and Firmicutes dominating both animal species. Phyla Armatimonadetes and Fusobacteria, as well as 64 genera, were detected only in alpacas, whereas phyla Acidobacteria and Nitrospira, as well as 44 genera, were found only in sheep. The abundance of cellulolytic bacteria, including Butyrivibrio and Pseudobutyrivibrio, was higher in alpacas than in sheep under all three diets. These differences in the forestomach microbial communities partly explained why alpacas displayed a higher poor-quality roughage digestibility, and a lower methane production. Results also revealed that the adverse effects of high-concentrate diets (70%) were lesser in alpacas than in sheep.     

Salvianolate attenuates oxidative stress injury of human endothelial EA.hy926 cells induced by hydrogen peroxide

AIM: To investigate the effect of salvianolate on oxidative damage induced by hydrogen peroxide in human endothelial EA.hy926 cells.METHODS: EA.hy926 cells were cultured in vitro and divided into the following groups:control group, damage group, and anti-damage groups (salvianolate+damage groups). The cell viability was measured by CCK-8 assay. The migration ability of the EA.hy926 cells was detected by Transwell assay. The content of nitric oxide (NO) in the culture supernatant of the EA.hy926 cells was examined. The levels of vascular endothelial growth factor (VEGF) were detected by ELISA. The apoptosis,mitochondrial membrane potential and intracellular superoxide anion content of the EA.hy926 cells were analyzed by flow cytometry. The protein levels of caspase-3, cleaved caspase-3, Bcl-2, Bax, NF-κB and p53 were determined by Western blot. RESULTS: Compared with damage group, the viability of EA.hy926 cells pretreated with salvianolate at different concentrations was significantly increased (P<0.05). The apoptotic rate was significantly decreased (P<0.05). Savianolate enhanced the migration ability of the cells. The levels of VEGF, NO and mitochondrial transmembrane potential were increased (P<0.05), and the intracellular ROS level was significantly decreased (P<0.05). The protein levels of NF-κB, p53, Bax and cleaved caspase-3 were significantly decreased, and the protein level of Bcl-2 was markedly increased(P<0.05). CONCLUSION: Savianolate reduces the damage of EA.hy926 cells by hydrogen peroxide exposure, and its mechanism may be related to the blocking of NF-κB signaling pathway.     

樱桃番茄抗青枯病砧木新品种海茄砧1 号的选育

海茄砧1 号是以野生茄子自交系HZ09-5 为母本，以从越南引进的茄子品种自交系HZ10-2 为父本育成的高抗青枯 病樱桃番茄砧木品种。植株生长势较强，第1 雌花节位约为第7 节，花为紫色，果实卵圆形，青熟果淡绿紫色或淡绿色，果 萼绿色，果长7～9 cm，果宽4～6 cm，单果质量为50～60 g，种子千粒重为3.2 g 左右，种皮浅黄色，高抗青枯病。海茄砧 1 号与樱桃番茄的嫁接亲和性好，共生性强，嫁接苗成活率高。嫁接后的樱桃番茄果萼开展，果面有光泽，可明显改善果实 VC、可溶性固形物和可滴定酸含量等品质，提高产量。适宜华南地区樱桃番茄的嫁接栽培。     

A rapid,simple, and sensitive immunoagglutination assay with silica nanoparticles for serotype identification of Pseudomonas aeruginosa

An agglutination test based on colored silica nanoparticles (colored SiNps) was established to detect serotypes of Pseudomonas aeruginosa. Monodisperse colored SiNps were used as agglutination test carriers. The colored SiNps were prepared through reverse microemulsion with reactive dyes, sensitized with 11 kinds of mono-specific antibodies against P. aeruginosa, and denoted as IgG-colored SiNps. Eleven kinds of IgG-colored SiNps were individually mixed with P. aeruginosa on a glass slide. Different serotypes of P. aeruginosa could be identified by agglutination test with evident agglutination. The P. aeruginosa could be detected in a range from 3.6 × 10⁵ to 3.6 × 10¹² cfu mL^?1. This new agglutination test was confirmed to be a specific, sensitive, fast, easy-to-perform, and cost-efficient tool for the routine diagnosis of P. aeruginosa.     

串番茄新品种红星302 的选育

红星302 是以抗病、耐低温弱光材料01-61 为母本，以01-23 为父本育成的串番茄一代杂种，无限生长类型，果实串收，果色亮红，果实椭圆形，酸甜适口，品质佳，VC 含量为364 mg · kg^-1，可滴定酸0.44%，可溶性糖4.25%，平均单果质量30.79 g，硬度为11.40×10⁵ Pa。单株结果数约为53个，产量4 900 kg ·（ 667 m²）^-1 左右，高抗蕨叶病毒病、青枯病，适宜河北地区冬季日光温室和早春保护地栽培。     

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。