沼液施用对潮土氧化亚氮排放通量的影响

通过对潮土养猪沼液施加试验,采用静态箱．气相色谱法于2010年7月（夏季）、2011年3月（冬末春初）观测了不施沼液、正常施沼液及大量施沼液等3种处理的土壤氧化亚氮（N20）排放通量,研究其排放特征与影响因素。研究结果表明：①沼液施用显著提高了氧化亚氮平均排放通量（P〈0．001）,不同沼液处理（不施沼液、正常施沼液、大量施沼液）排放通量范围分别为11-25～68147μg·m-2·h-1,20．13～244．35μg·m-2·h-1,40．09～618．43μg·m-2·h-1;②土壤氧化亚氮排放通量除受沼液施加水平影响外,还随着土壤温度的提高而增加：③土壤氧化亚氮排放通量与土壤水分呈极显著相关（P〈0．001）．与土壤硝态氮质量分数显著相关（P〈0．05）;④以相同施氮量计,沼液施加引起的氧化亚氮排放速率远高于尿素或者硫胺等氮肥。图3表1参22     

滴灌水氮管理对玉米种植土壤无机氮含量和氧化亚氮排放的影响

【目的】获得玉米种植土壤氧化亚氮(N₂O)减排的滴灌施肥模式，揭示不同滴灌灌水量和施氮比例下土壤无机氮含量对土壤N₂O排放的影响。【方法】在移动防雨棚内开展2季玉米3种滴灌灌水量(W60、W80和W100分别为田间持水量的50%～60%、70%～80%和90%～100%)和2种滴灌施氮比例(等N量为180 kg·hm-2，其中，F55为50%氮肥作基肥土施、50%氮肥作滴灌施肥，F37为30%氮肥作基肥土施、70%氮肥作滴灌施肥)的田间试验，测定生育期内土壤N₂O通量和不同生育时期土壤无机氮含量，计算不同生育时期和全生育期土壤N₂O排放量，分析土壤N₂O通量与土壤无机氮含量之间的关系。【结果】2季玉米土壤的N₂O排放规律相似；相同施氮比例下，W100水分处理下土壤N₂O排放通量在多数玉米生育时期高于W60和W80，表明高水分处理下土壤N₂O排放通量高于中、低水分处理；相同水分处理下，除夏季玉米苗期外，土壤N     

不同基肥施用方式及用量对冬小麦田NO排放通量的影响

用静态箱法对冬小麦不同基肥施用方式(表施、深施)和不同施用量下的土壤NO排放通量进行了研究,结果表明:肥料在土壤中的位置对NO排放通量的影响非常显著。表施处理明显促进NO的排放,表施处理平均比深施处理NO排放量高2.2倍。高肥处理总的NO排放量也明显高于低肥处理。由此可知肥料深施和减少用量都能显著降低NO排放量。     

北京京郊果园施用不同农肥的土壤呼吸特征研究

    为准确揭示北京京郊不同施肥类型果园的土壤呼吸差异,利用LI-8100开路式土壤碳通量测量系统,测定并分析平谷桃园单施化肥、有机肥和化肥混施、单施有机肥3种典型施肥类型的夏季土壤呼吸昼夜变化状况.结果显示:桃园不同施肥类型的土壤呼吸速率昼夜变化都表现为单峰曲线;有机肥施用小区的土壤日呼吸速率、日碳通量、月碳通量及生长期碳通量均最高.各样地的土壤5 cm温度、近地面大气气压、湿度和CO2浓度等环境因子以及土壤有机碳含量、土壤微生物数量、土壤微生物量碳、土壤水分等土壤因子都对土壤呼吸速率具有明显的影响.对不同施肥类型土壤呼吸的分析结果表明,研究地有机肥与化肥配合施用既可以提高土壤有机碳含量,土壤全天CO2释放量也最低;化肥施用小区土壤全天CO2释放量高于有机肥和化肥混施的土壤,但其土壤有机碳、微生物数量及微生物量碳较低;有机肥施用小区的有机碳、微生物数量和微生物量碳最高,但也有着旺盛的土壤呼吸.说明有机肥和化肥混施有助于降低桃园土壤CO2的释放量.     

含ACC脱氨酶的根际促生菌对切花月季生长的影响

【目的】探明含ACC脱氨酶（1-aminocyclopropane-1-carboxylate deaminase）的不同植物根际促生菌对切花月季白荔枝的促生效果。【方法】以白荔枝为试验材料，在其盆栽过程中施入含ACC脱氨酶的不同PGPR菌株，通过测定其株高、茎粗、分枝数等农艺性状、叶绿素a/b值、叶片保护酶活性及MDA含量、花朵乙烯释放量、光合及叶绿素荧光参数等生理指标，探讨不同菌株对白荔枝生长及生理的影响。【结果】施入含ACC脱氨酶的不同PGPR菌株对白荔枝生长及光合作用产生的影响有所差异，其中菌株F23和F195处理较对照株高增加25.9%和26.0%，且F23处理后茎粗比对照处理增加17.1%，菌株F23和F195处理叶绿素a/b也高于对照。菌株F23显著提高了根际土壤脲酶、磷酸酶和蔗糖酶活性至42.6%、 16.3%和48.8%；且菌株F23对POD以及CAT活性的提高有显著促进作用，分别达到对照的1.78和2.07倍，花朵乙烯释放量比对照减少37.8%。净光合速率经菌株F195和F23处理后显著高于对照，分别达对照的1.40倍和1.16倍。【结论】综合比较认为，菌株F23对...     

大豆N2O释放与光照度和光合作用的关系

采用分隔式封闭箱法，测定盆栽大豆植株氧化亚氮（N2O）通量以及光照度、光合速率和气孔导度的日变化。同时，观测田间大豆—土壤系统在主要生长阶段N2O释放的变化。在温室里，大豆植株N2O释放在上午10：00时出现一个高峰；中午时N2O释放量较低，此时光照度和光合速率都保持在较高的水平上；在14：00时，N2O释放量达到低谷,光照度达到最大，但光合速率却处于很低的水平；在15：00时，植株N2O的释放达到第二个高峰，但光照度和光合速率却处于快速下降期。结果表明：植物N2O的释放不仅与光合作用的光反应有关，而且也与暗反应有关。上午10：00以后植株N2O释放通量与气孔导度变化没有一致的关系。在大豆生长季，大豆—土壤系统N2O释放通量有两个高峰，第一个峰出现在6月中下旬，第二个高峰出现在9月下旬。     

沼液施用对土壤温室气体排放的影响

 采用静态箱-气相色谱法,于2010年7月（夏季）、2011年3月（冬季）进行了不同沼液施用量对土壤二氧化碳（CO₂）,甲烷（CH₄）和氧化亚氮（N₂O）气体排放影响的研究。试验期间,沼液施用设为大量施沼液（夏季为28.36 g·m^-2,冬季为1.94 g·m^-2）,正常施沼液（夏季为9.45 g·m^-2,冬季为0.65 g·m^-2）和不施沼液等3个水平。结果表明：①夏季或冬季,处理对土壤二氧化碳排放影响均不显著。②夏季沼液施用8 h内,处理间对土壤甲烷排放具极显著差异（P＜0.001),其中大量施沼液时通量最大为3.98 mg·m^－2·h^－1;正常施沼液时通量最大为1.25 mg·m^－2·h^－1,8 h后处理间无显著差异（P＞0.05）。冬季在大量施沼液时,初期土壤甲烷排放通量明显高于正常施沼液及不施沼液,最大为0.28 mg·m^－2·h^－1;随后处理间土壤甲烷排放通量无显著差异。③夏季沼液施用20 h内,处理间对土壤氧化亚氮排放具极显著差异（P＜0.001）,最大值达1 641 μg·m^－2·h^－1;处理间呈显著差异（P＜0.05）,大量施沼液、正常施沼液和不施沼液时土壤氧化亚氮排放通量分别为224～349,70～137,33～57 μg·m^－2·h^－1;冬季则处理间土壤氧化亚氮排放无显著差异。图3参19     

秸秆配施氮磷化肥对潮土氮磷含量变化的影响

采用室内恒温培养法研究了秸秆配施氮、磷肥对潮土供氮磷特性的影响．结果表明：秸秆施入土壤２～３个月后，土壤碱解氮有明显提高．秸秆单施或与磷肥配施，矿化过程表现为前期净固持后期净矿化．配施氮肥，麦秸和玉米秸前期矿化氮释放量很少，而花生秸矿化可明显提高土壤碱解氮水平．不同秸秆矿化对土壤速效磷影响不同，这与其Ｃ／Ｐ比有关，但前期（１～２个月）都能提高土壤速效磷水平．     

冬小麦田氧化亚氮的排放

对１９９０－１９９２年间冬小麦田氧化亚氮排放的日变化和季节变化进行了研宪，观测了Ｎ＿２Ｏ通量与土壤温度的关系。在整个实验阶段，不施肥田和施肥田Ｎ＿２Ｏ通量的平均值为１０．５μｇＮ／ｍ￣２·ｈ和２２．６μＮ／ｍ．ｈ。小麦地上所施尿素排放Ｎ＿２Ｏ－Ｎ的释放系数为０．０９％。     

大气温度对土壤养分迁移和春小麦干物质积累的效应

试验设22℃和28℃两种温度水平，并设N1P1K1，N1P2K2，N2P1K1，N2P2K24个肥料水平。结果表明，高氮时，28℃时春小麦地上部干物重，根干物重，干物质总量和根冠比率比22℃时平均分别下降27％，42％，30％，20％，根系氮、磷、钾浓度和小麦对氮、磷、钾的吸收较22℃时也低。根际土壤pH约比土体pH降低0．2，温度对根际土壤pH值会产生影响，但不同氮肥用量处理表现不同，低氮时，22℃时根际土壤pH值比原土降低0．3，而28℃时根际土壤pH值并不降低；高氮时，22℃和28℃根际土壤pH值均比原土降低，但28℃时降低更多。高氮28℃温度处理根际土壤NO3^-－N含量远比土体高，28℃时根际土壤NO3^--N含量比22℃时要高，氮肥用量高时更为明显。根际土壤速效P含量比土体速效磷低，28℃温度时根际土壤速效磷量较高。     

Web2.0,以个人为中心的互联网时代的到来

本文介绍了Web2．0的知识和背景，对Web2．0出现的基础以及典型技术和应用作了阐述，同时对其作出了前景展望。     

市级综合气象信息分析与管理系统的设计与实现

以抚顺地区3个国家基本站50余年气象资料为依托，采用Microsoft Excel工作表实现由气候和农业气候2部分构成的气象与农业综合信息处理系统的基本思路、方法、内容、用途和使用情况。为了实现气候分析及应用的科学化、客观化、系统化、规范化、程序化及连续化的业务目标，按业务流程设计与实现的，包括资料处理、气候趋势模拟、气候预测、气候鉴定、季节性信息化处理、农作物产量预报、气候生产潜力分析等一系列内容在内的系统建设。关键是解决了大量的计算问题，建立了区域性通用模式。     

Multi-variable grey model (MGM (1,n,q)) based on genetic algorithm and its application in urban water consumption

Urban water consumption has some characteristics of grey because it is influenced by economy, population, standard of living and so on. The multi-variable grey model （MGM（1,n））, as the expansion and complement of GM（1,1） model, reveals the relationship between restriction and stimulation among variables, and the genetic algorithm has the whole optimal and parallel characteristics. In this paper, the parameter q of MGM（1,n） model was optimized, and a multi-variable grey model （MGM（1 ,n,q）） was built by using the genetic algorithm. The model was validated by examining the urban water consumption from 1990 to 2003 in Dalian City. The result indicated that the multi-variable grey model （MGM（1,n,q）） based on genetic algorithm was better than MGM（1,n） model, and the MGM（1,n） model was better than MGM（1,1） model.     

Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa

Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.     

不同施肥水平对木薯氮磷钾养分积累、分配及其产量的影响

 【目的】通过比较不同施肥水平下木薯氮磷钾养分积累、分配和产量的差异，探讨粤北坡岗地优质高产木薯氮磷钾养分的最佳用量。【方法】以木薯品种南美119为材料，采用“3414”方案，在粤北翁源进行大田试验。试验共设14个处理。【结果】施肥处理的氮素主要分配到地上部，不施肥处理的氮素则主要分配到根部；不同施肥处理的磷素均主要分配到地上部；不施肥处理和不施钾处理的钾素主要分配到根部，不施氮处理的钾素在根、冠间分配较均衡。在木薯不同生长阶段，植株氮磷钾含量均呈下降趋势，但施氮、磷、钾化学肥料处理植株氮磷钾含量的下降速度小于不施氮、磷、钾化学肥料的处理。处理N2P2K2的氮、磷、钾含量和积累量在各生育期均为最大，不施肥处理（N0P0K0）的氮、磷、钾含量和积累量在各生育期均为最小（P＜0.05）。产量最高的是N2P3K2处理，为22 694.06 kg·hm-2，其次是N2P2K2处理，为21 417.87 kg·hm-2。【结论】木薯产量、氮磷钾养分积累及其在根冠间的分配，对施肥水平高度敏感, 适当比例的氮磷钾肥配合施用既可以显著增加木薯植株的氮磷钾含量和积累量，又可以提高产量。在粤北坡岗地木薯生产中，氮素最重要，在氮素得到满足的条件下，磷素较钾素更重要。在本试验条件下，氮磷钾养分最佳用量为358.80 kgN·hm-2、89.10 kg P2O5·hm-2和187.50 kg K2O·hm-2。     

红苕饲粮中添加铜和/或喹乙醇对猪生产性能及某些血液生化指标的影响

选体重约38公斤的长白(♂)×成华(♀)杂交猪20头,随机分为四组,饲予四种不同的饲粮,研究饲粮中添加铜和/或喹乙醇对猪生产性能和某些血液生化指标的影响。结果表明:基础组、加铜组、加喹乙醇组和两者同时加组全期日增重分别为674、761、796、678克,日采食量分别为2.50、2.65、2.74、2.40公斤,饲料利用率分别为3.73、3.49,3.44、3.54,添加铜和/或喹乙醇对试验第65天血清铜兰蛋白、尿素氨及屠宰率、背膘厚和眼肌面积无显著影响(p>0.05);添加铜使65天血清碱性碱酸酶活性极显著增高(p<0.01),添加喹乙醇有使之升高的趋势,两者同时添加时,碱性酸磷酶活性降低。     

Current progress on genetic interactions of rice with rice blast and sheath blight fungi

Analysis of genetic interactions between rice and its pathogenic fungi Magnaporthe oryzae and Rhizoctonia solani should lead to a better understanding of molecular mechanisms of host resistance, and the improvement of strategies to manage rice blast and sheath blight diseases. Currently, dozens of rice resistance (R) genes against specific races of the blast fungus have been described. Among them, ten were molecularly characterized and some were widely used for breeding for genetic resistance. The Pi-ta gene was one of the best characterized rice R genes. Following the elucidation of its molecular structure, interaction, distribution, and evolution, user friendly DNA markers were developed from portions of the cloned genes to facilitate the incorporations of the Pi-ta mediated resistance into improved rice varieties using marker assisted selection (MAS). However, rice blast is still a major threat for stable rice production because of race change mutations occurring in rice fields, which often overcome added resistance based on single R genes, and these virulent races of M. oryzae pose a continued challenge for blast control. For sheath blight, progress has been made on the exploration of novel sources of resistance from wild rice relatives and indica rice cultivars. A major quantitative trait locus (QTL), named qSB9-2, was recently verified in several mapping populations with different phenotyping methods, including greenhouse methods. The ability to identify qSB9-2 using greenhouse methods should accelerate the efforts on the qSB9-2 fine mapping and positional cloning.     

Virus Location and Lymphocyte Apoptosis in Lymph Nodes of Piglets Infected with PCV-2

The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ （PCV-2）. Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups： control group （n = 3）, piglets inoculated with PCV-2 alone （PCV-2, n = 3）, and PCV-2 inoculated and KLH immunostimulated group （PCV-2 ＋ KLH, n = 3）. Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. Location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling （TUNEL） and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 ＋ KLH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEL, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 ＋ KLH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 ＋ KLH piglets were significantly higher than those for the control group （P〈0.05 and P〈0.01）. The proliferation index （PI） was 0.17_＋0.01, 0.12_＋0.01 and 0.12_＋0.04 in the control, PCV-2, and PCV-2 ＋ KLH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one o     

锌对镉·汞复合污染下豌豆幼苗生长的影响

以豌豆为试验材料,采用水培方法研究了锌对镉、汞复合污染下的豌豆种子萌发与生长的影响。结果显示,锌浓度≤100.0 mg/L时促进豌豆种子的萌发,锌浓度为200.0和300.0 mg/L时抑制豌豆种子的萌发。当镉、汞的浓度为3.0 mg/L时,100.0 mg/L锌的解毒效应最明显,表现为能够促进镉、汞胁迫下豌豆种子萌发和幼苗生长,降低豌豆幼苗根尖细胞畸变率,提高豌豆幼苗的叶绿素含量及过氧化物酶活性;但当锌浓度≥200.0 mg/L时,与镉、汞协同迫害豌豆幼苗的生长。     

仙人掌超氧化物歧化酶提取与纯化研究

以仙人掌为试验材料,采用硫酸铵分级沉淀法得到超氧化物歧化酶（Superoxide Dismutase,SOD）粗酶液。然后用Sephadex（葡聚糖凝胶）G-75层析柱层析对粗酶液进行进一步纯化,最后用邻苯三酚法测定酶活力,并对酶活力主要影响因素（包括pH值、温度、抑制剂）进行了研究。结果显示仙人掌SOD酶比活力为751.56U.mg-1。pH值为7.5~8.5时酶活力最大,稳定性也好。温度维持在25~30℃时酶活力最高。由于过氧化氢和氰化钾均能使仙人掌SOD的酶活力显著下降,因而可以初步判断从仙人掌中提取到的SOD是Cu.Zn-SOD。