内蒙古高原紫花苜蓿土壤氮素丰缺指标和推荐施氮量     

米春娇  孙洪仁  王显国  高凯  张玉霞  刘庭玉 《草地学报》2021,29(12):2785-2791

为了给内蒙古高原紫花苜蓿（Medicago sativa L.）测土施氮奠定科学基础，本研究采用“零散实验数据整合法”和“养分平衡-地力差减法”新应用公式，开展了该自然区域紫花苜蓿土壤氮素丰缺指标和推荐施氮量研究。结果表明：内蒙古高原生长第1年紫花苜蓿土壤碱解氮第1~6级丰缺指标为≥48，20~48，8~20，4~8，2~4和<2 mg·kg^-1，土壤全氮第1~5级丰缺指标为≥1.4，0.8~1.4，0.4~0.8，0.2~0.4和<0.2 g·kg^-1，土壤有机质第1~6级丰缺指标为≥17，10~17，6~10，3~6，2~3和<2 g·kg^-1。当紫花苜蓿目标产量9~18 t·hm^-2、氮肥利用率40%时，内蒙古高原紫花苜蓿第1~6级土壤推荐施氮量分别为0，68~135，135~270，203~405，270~540和338~675 kg·hm^-2。  相似文献   

猪口蹄疫O型灭活疫苗PD50效检攻毒方式探索   总被引：2，自引：2，他引：0  

郎洪武  闫岩  张荣军  肖怀红  杨汉春 《中国兽药杂志》2004,38(3):26-27

用10 000 TCID50的OR/80株F13细胞毒或用10 000 LD50的OR/80株乳鼠组织毒(ORMF8),通过肌肉注射途径、蹄踵球部或趾间皮内注射途径接种O型口蹄疫抗体阴性架子猪进行攻毒试验,三种途径均不能使试验猪产生规律性发病.  相似文献   

新鲜蔬菜硝酸盐含量测定的改进试粉法   总被引：11，自引：0，他引：11  

杜应琼  王富华  李乃坚  袁利升  苏青云 《园艺学报》2005,32(1):49-53

 为适应新鲜蔬菜硝酸盐快速检测的需要, 在现有试粉法的基础上对硝酸盐测定的试粉法进行了改良研究。结果表明, 本研究建立的直接以去离子水浸提蔬菜匀浆, 混合试粉配方为柠檬酸∶一水硫酸锰∶无水对氨基苯磺酸∶N - 1 - 萘乙二胺盐酸盐∶细锌粉= 30∶4∶1.6∶0.8∶1, 其加入量为0.1 g的改进试粉法, 对于溶液中硝酸盐含量在0～20 mg/L范围时, 显色吸光值与硝酸盐含量呈现良好的线性关系, 相关系数达0.9999, 方法回收率在97.7%～104.5%之间, 相对标准偏差2.71%。用本改进试粉法测定11种蔬菜的硝酸盐含量与国标法测定结果的t检验具有一致性。  相似文献   

离体条件下水稻种衣剂对串珠镰刀菌生长及形态毒理影响     

刘西莉  张龙  李健强  房双龙 《植物病理学报》2002,32(4):332-337

 检测了黑龙江水稻主产区4个当地主栽品种的种子内部镰刀菌寄藏情况,测定了20%克福甲和20%克多甲种衣剂对种子带菌消毒处理效果及对水稻串珠镰刀菌(Fusarium moniliforme)的抑菌作用和联合毒力,并借助扫描电镜观察了上述2种混配种衣剂对串珠镰刀菌的形态毒理影响。结果表明,种子内部镰刀菌的分离频率高达56.7%~96.0%,其中串珠镰刀菌的分离频率为32.6%~48.2%,2种种衣剂对带菌种子具有显著的消毒处理效果。20%克福甲和20%克多甲种衣剂对镰刀菌F.moniliforme的毒力指数分别为457.11和802.04,增效倍数分别为6.53和0.13。20%克多甲种衣剂(多菌灵:甲基立枯磷为5:5,W/W)对串珠镰刀菌的抑菌作用优于20%克福甲种衣剂(福美双:甲基立枯磷为8:6,W/W),增效作用低于20%克福甲种衣剂。电镜观察表明,种衣剂低浓度至高浓度处理下均可引起串珠镰刀菌菌丝不同程度的异常生长,表现为主菌丝局部膨大或形成菌丝束,菌丝顶端异常膨大、缢缩或形成穗状和花絮状分枝。  相似文献   

Assessing exterior egg quality indicators using machine vision     

A. V. Vasileva  E. V. Gorbunova  A. S. Vasilev  V. S. Peretyagin  A. N. Chertov  V. V. Korotaev 《British poultry science》2018,59(6):636-645

ABSTRACT

1. The objective of this study was to develop a machine vision method for analysing exterior parameters of chicken eggs to automate the stage of primary sorting.

2. The developed algorithm based on predetermined thresholds calculated egg quality indicators, including geometric dimensions, shape index and the mottling grade. The algorithm was implemented with an experimental setup that combined the image-based and the candling methods. A total of 400 egg samples were analysed.

3. Comparison of results of the algorithm with those obtained using the traditional manual method showed that mean value of radii values difference was 0.095 ± 0.058 mm for the sharp and 0.080 ± 0.047 mm for the blunt end of the egg, with standard deviations of 0.58 mm and 0.49 mm, respectively.

4. The correlation coefficient between the shape index values determined by the two methods was 0.93; the standard deviation of absolute differences between corresponding values was 1.05%.

5. The results of mottling grade estimation were compared using F-measure and confusion matrix.

6. The results allow the possibility to perform the assessment of egg exterior quality factors in an automatic mode, independent of the expertise of a grader.  相似文献   

立式无筛饲料超微粉碎机的研发及质量检测分析     

葛一健  王君 《渔业现代化》2011,(5)

介绍了我国立式无筛饲料超微粉碎机的发展,简述立式无筛饲料超微粉碎机的组成、工作原理和优越性,分析质量检测及立式无筛饲料超微粉碎机技术的发展,展望制定行业标准的预期效果。  相似文献   

水质快速检测设备的硬软件设计及实现     

高超  胡孟  吴国荣  宋卫坤 《安徽农业科学》2015,(35)

[目的]研制本质快速检测设备,实现水质的现场多指标快速检测.[方法]对设备的硬件及软件进行了设计.硬件设计包含了1P2303芯片、锂电,Cortex-M3型ARM微控制器、树莓派显示系统、光频转换器等的设计;软件设计则包含了软件设置、项目选项、项目测量结果以及测量数据表格输出等模块的设计;并对水质快速检测设备的可靠性进行了试验检验.[结果]通过对该设计的设备硬件和软件合理搭配连接,从而研发出了水质快速检测设备.用该设备与国家标准要求的设备同时测定某一河道水样的5项指标结果发现,3个样点水样中铁、氨态氮、氟化物、硝酸盐和6价铬含量的两组数据值接近,无明显差异.虽然国家标准法检测下限比快测法高一个数量级,但快速设备的测定结果不影响操作员对水质的判断,说明该水质快速检测设备精密度高;两种测定方法的稳定性比较,结果快速测定法的5个指标数据的相对偏差略高于国家标准法(3.92％),但其测定结果能够较好地满足现场测定要求,说明该水质快速检测设备稳定性良好.[结论]该水质快速检测设备的检测精度和稳定性较高,可满足水质的现场快速检测要求.  相似文献   

Collembola in ecotoxicology—Any news or just boring routine?     

《Applied soil ecology》2014

Despite the uncontested significance of soils for human nutrition and drinking water quality, the majority of ecotoxicological testing is confined to aquatic test systems. Among the standardised tests for soils, the reproduction test with the springtail Folsomia candida is among the most widely used ones. First steps towards its standardisation were undertaken in the late 1980s. Here we review major advances that have been made since then, with respect to mechanistic, pragmatic and ecological aspects. Specifically we address the ecological relevance of any modifications of the standardised tests. We introduce a miniaturised version of the reproduction test which allows reducing the amount of soil per test unit to one third and the number of synchronised individuals to 40% as compared to the standard test. In addition, we developed an assay using Collembola eggs instead of synchronised adults. First results of a three-species test indicate that the presence of other species may affect choice behaviour. We point out a potential biased view of existing ecotoxicological data with Collembola due to the fact that most results refer to metal contamination. Finally, recommendations for future research are given, with special reference to avoidance and microcosm tests involving Collembola.  相似文献   

便携式XRF仪现场快速测定土壤中Pb的可行性研究     

柳伟  许伟  孙东  赵松江 《安徽农业科学》2017,45(33)

便携式XRF分析仪具有轻便、快速和可测对象较多与测量元素较广等特点而广泛应用于矿石、土壤等方面快速检测,但土壤的现场快速测定结果的准确性有待进一步研究与探讨。以安宁河谷平原土壤中Pb为研究对象,通过对便携式XRF仪现场快速检测结果与实验室分析结果的对比和影响因素的分析,建立基于安宁河谷平原表层土壤快速测定结果的线性函数为y=1.170 9x-17.326 0(R~2=0.992 9,x为现场检测结果),探讨其影响因素,为该区域表层土壤中Pb快速检测结果提供依据。  相似文献   

Soil available potassium affected by rice straw incorporation and potassium fertilizer application under a rice–oilseed rape rotation system     

Dandan Zhu  Jianglin Zhang  Zheng Wang  Rizwan Khan Muhammad  Jianwei Lu  Xiaokun Li 《Soil Use and Management》2019,35(3):503-510

Data from 147 field trials were collected to study the influence of straw incorporation on soil potassium (K) under an intensive rice–oilseed rape rotation system, while pot experiments were conducted to evaluate the effects of rice straw incorporation on soil K availability. A significant correlation was observed between the soil available K and the relative yield (RRY) and the relative K uptake (RKU) of oilseed rape, with R² values ranging from 0.07 to 0.08 and from 0.10 to 0.11, respectively, when data were fitted to a logarithmic equation model. In approximately 30% of trials, RRY reached 90%, while soil test available K values were below the critical limit, indicating that soil K values at the time of sampling (within 1 week of rice harvest) underestimated the actual soil K supply capacity. The pot experiment results showed that soil available K was affected by straw incorporation and soil type in the fallow period. The NH₄OAc‐K and NaBPh₄‐K concentrations of soils increased at first, and then, plateaued after 28 days. Straw incorporation significantly influenced the critical soil K concentration, which is important for making accurate K fertilizer recommendation. These results suggested that straw K should be seriously considered in making K fertilizer recommendations. Extending the sampling time from 1 to 3 weeks after the harvesting of rice to stabilize the effects of straw incorporation may help achieve a more accurate evaluation of soil available K.  相似文献