国内外有机肥标准对比及风险评价

中国是人口最多的发展中国家，生产生活中产生的有机废弃物数量巨大，堆制有机肥是降低有机废物污染风险的重要方式，而有机肥标准则是防止有机肥成为新的土壤污染源，规范有机肥产业健康发展的重要保障。目前我国有机肥不合格现象时有发生，针对有机堆肥的标准仅有一个8年前的行业标准（NY 525—2012）的现状，本文对比了中国、日本、澳大利亚、欧盟、美国有机肥标准的重要指标，对存在的重金属残留、抗生素污染、病原体污染、营养富集及土壤盐渍化等有机肥质量安全风险问题进行分析，为我国有机肥行业未来绿色、健康、可持续发展提出建议。尽管我国现有有机肥质量标准，在具体指标要求方面优于美国，但和欧盟相比还有差距，比如我国重金属Cu、Zn、Ni限量缺失，对Cd等重金属限值要求不够严格，长期施用会导致土壤重金属含量超过风险筛选值，严重影响农作物安全；同时，由于部分畜禽养殖业不合理使用抗生素，加之有机肥生产企业技术的欠缺，农户施用时缺乏指导，监管部门执法不严等因素，我国有机肥施用过程存在较大风险隐患。因此，进一步完善有机肥标准体系，强化对原料中有毒有害物质的限制，要求选用原料批批检，加大准入和过程的落实力度，才能保障我国有机肥产业有序健康发展。     

Investigations into the temporal development of epitheliocystis infections in brown trout: a histological study

Epitheliocystis in Swiss brown trout (Salmo trutta) is a chlamydial infection, mainly caused by Candidatus Piscichlamydia salmonis and Candidatus Clavichlamydia salmonicola. To gain a better understanding of the temporal development of infections in wild brown trout, we investigated epitheliocystis infections during the course of the summer and autumn months of a single year (2015), and compared this to sampling points over the span of the years 2012–2014. The survey focused on tributaries (Venoge and Boiron) of the Rhone flowing in to Lake Geneva. When evaluated histologically, epitheliocystis infections were found throughout the period of investigation with the exception of the month of June. Fifty to 86 animals per sampling were investigated. Highest prevalence and infection intensities were seen in September. A correlation between epitheliocystis infection and water temperatures was not evident. Interyear comparison revealed consistent levels of prevalence and infection intensities in late summer. The absence of infections in June, combined with the consistent interyear results, indicates seasonal fluctuation of epitheliocystis infections in brown trout with a reservoir persisting during winter months from which infections can re‐initiate each year. This could either be at levels below detection limits within the brown trout population itself or in an alternative host.     

不同运输条件对合浦珠母贝稚贝存活比较

比较运输方式及环境温度对合浦珠母贝稚贝运输中的存活影响,从而为稚贝运输过程中的运输方式、环境温度及运输时间的把握提供借鉴和参考。以3月龄稚贝为实验材料,运用无水干露、加水淹没及包装充氧等3种方式,分别在环境温度为5、13、21和29℃下模拟运输。每隔3 h从每组运输条件下取出1组实验贝,转移到正常养殖环境下暂养恢复,经48 h后统计其存活率。对运输时间与存活率之间进行非线性参数曲线拟合,计算每组运输条件下的致死时间(T_0)、半致死时间(T_(0.5))及全致死时间(T_1);运用双因素方差分析,Duncan氏方法比较3种运输方式及4种环境温度间的均值。结果显示:包装充氧优于其他两种运输方式,而加水淹没又优于无水干露;温度为13℃和21℃时优于其他2个环境温度,环境温度为17.60～20.05℃是稚贝运输的最佳温度。     

黄秋葵品种比较试验

为筛选出适合萍乡地区种植的黄秋葵优良品种,为黄秋葵的进一步应用奠定资源基础,对10个黄秋葵品种进行了品种综合性状鉴定。结果表明:赣葵1号、赣葵3号、赣葵4号、枫桥秋葵生长势强,果实品质好,产量较高,2年平均667 m~2产量均在1 800 kg以上,可以大面积推广。赣葵4号、萍乡红葵的果实颜色鲜艳,可兼作观赏品种。     

高品质番茄比较试验

为丰富嘉善县番茄品种,通过引进4个高品质番茄与嘉善县大面积种植品种进行对比试验。结果表明:引进的大果型番茄浙粉712和浙粉716虽然产量较当地番茄品种惠福低,但果实口感较好,且大小均匀,整齐度较好,适合在当地进行一定面积的推广;引进的中果型番茄光辉101和樱桃番茄浙樱粉1号,果实大小均匀、口感好、番茄风味浓,且生长势强,经济效益突出,667 m~2产值较当地菜用番茄高出12 000～18 000元,适合采摘或短途运输销售。     

Using vibrational molecular spectroscopy to detect moist heating induced carbohydrates structure changes in cool-climate adapted barley grain

There is limited research to study how moist heating affects internal structure of barley grain on a molecular basis. The objectives of this study were to use vibrational molecular spectroscopy: 1) to determine the moist heating induced changes of barley carbohydrate (CHO) structure on a molecular basis, 2) to study the effects of moist heating on CHO chemical profiles, Cornell Net Carbohydrate and Protein System (CNCPS) subfractions, in situ rumen degradation, and predicted intestinal carbohydrate supply of barley grain; and 3) to reveal the association between molecular structure spectral features and CHO related metabolic characteristics. Barley samples (CDC cowboy) were collected from Kernen Crop Research Farm (Saskatoon, Canada) during two consecutive years. Half of each sample was kept as raw barley and the other half underwent moist heating (autoclaving at 120 °C for 60 min). The molecular spectroscopy (attenuated total reflectance-fourier transform infrared, ATR-FTIR) was used to detect the barley CHO related molecular structure spectral features. Moist heating did not affect carbohydrate related chemical profiles and CNCPS subfractions but it decreased rumen degradable carbohydrate. Rumen undegradable and intestinal digestion of CHO subfractions were not affected by moist heating. The advanced vibrational molecular spectroscopy can be used to detect carbohydrate molecular spectral features. Nutrient utilization prediction using molecular spectral characteristics is warranted and further investigation is encouraged.     

籽用西葫芦新品种比较试验

为了解决新疆昌吉地区籽用西葫芦品种繁杂、产量不高、效益不好等问题,从山西省引进10个籽用西葫芦新品种,通过田间试验比较分析了各品种的生育期、植物学性状、果实性状、籽粒性状、抗病性及产量等指标,初步筛选出3个适合新疆昌吉地区种植的籽用西葫芦品种,分别为籽瑞宝、ZHL-3和华仁九号,3个品种白粉病、病毒病发病率均在10%及以下,667 m~2籽粒产量175 kg以上。     

Genome-wide comparison of Carnobacterium maltaromaticum derived from diseased fish harbouring important virulence-related genes

Although Carnobacterium maltaromaticum has been used as a probiotic in fish, it was reported to cause disease for the first time in Korea. The objective of this study was to understand the differences between pathogenic and non-pathogenic strains. Pathogenicity was tested by challenging rainbow trout with C. maltaromaticum ATCC35586 and 18ISCm isolated from diseased fish, and DSM20342 isolated from a dairy product. We also compared 24 genomes of C. maltaromaticum strains plus the genome of our isolate 18ISCm sequenced in this study. Only the strains from diseased fish caused high mortality with severe histopathological changes. Although all strains shared more than 90% of Ko_id, wecC and xtmA were found only in strains from diseased fish. Interestingly, only strains from diseased fish harboured two wecC paralogs involved in the production of D-mannosaminuronic acid which is a major component of a well-known virulence factor, teichuronic acid. Two wecC paralogs of 18ISCm were increased when they were co-cultured with trout blood cells, suggesting that wecC genes might play a role in virulence. The results of this study show that strains isolated from diseased fish are different from strains derived from food in terms of pathogenicity to fish and the presence of virulence-related genes.     

仙居县杨丰山优质稻米品种比较研究

为筛选出适合仙居杨丰山地区种植的优质高产水稻品种,笔者引进了11个杂交籼稻品种和3个籼粳交品种,在杨丰山村开展了品种比较试验,综合考察品种的产量、生育期和抗逆性。结果表明,中64优华占产量优势明显、综合性状表现较好,可作为当地大面积种植的备选品种;桃优香占的米质特优、产量适中,可用于高档稻米的订单生产。     

中国农业企业全要素生产率区域比较及驱动因素分析——基于1 126家国家重点龙头企业

使用2013—2015年农业产业化国家重点龙头企业数据,测度中国各地级市农业企业全要素生产率,并进行空间比较,在此基础上,并就影响中国农业企业全要素生产率的相关因素进行分析。结果显示:1)整体来看,2013—2015年中国农业企业全要素生产率变动幅度不大;2)从各省份来看,农业企业全要素生产率差异较为明显,仅有个别省份全要素生产率呈现递增趋势;从各地市来看,各地市农业企业全要素生产率空间差异大,但是各地市农业全要素生产率排名变化不大,全要素生产率处于中高水平以上的企业不多;3)从影响中国农业企业全要素生产率的因素来看,研发投入、要素密集度和企业规模对中国农业企业全要素生产率的影响为正,企业出口并未对农业企业全要素生产率起到推进作用。