北京地区草坪杂草防治的初步研究

在摸清北京地区不同类型草坪中不同杂草种类的基础上，选择了一定效果的除草剂对这些优势种进行了２个生长季节的防治试验。结果表明，不同除草剂对草坪草敏感程度和防治效果不一样。在使用除草剂防治草坪杂草时一定要谨慎，否则将出现较大药害。     

The effects of the herbicide metsulfuron-methyl on litter invertebrate communities in a coastal dune invaded by Chrysanthemoides monilifera spp. rotundata

We investigated the impacts of application of the sulfonylurea herbicide, metsulfuron-methyl, on soil and litter invertebrates in coastal vegetation where the weed Chrysanthemoides monilifera has invaded. We followed changes in litter invertebrates for 125 days following treatment to investigate direct toxic and indirect effects of treatment. Overall we found no effect of treatment on abundance, taxonomic richness or composition of litter invertebrates. In general, abundance and richness declined with time in both treated and untreated sites, suggesting that climatic factors were far more important in determining invertebrate communities than the effects of the treatment. Even changes in cover of vegetation as a result of death of the weed resulted in few measurable effects on invertebrates. It is concluded that metsulfuron-methyl had no impact on invertebrate communities up to 125 days following treatment.     

绵阳市水稻青立病发病原因及防治技术研究

【目的】探讨绵阳市水稻青立病发病原因和防治措施。【方法】采取调查分析与田间试验的方法，比较不同除草剂处理水稻青立病发病情况，测定发病田块土壤和水稻植株重金属种类及含量，初步明确绵阳市水稻青立病发病原因；分析不同防治手段下水稻青立病发病情况，探索水稻青立病防治措施。【结果】施用除草剂不会引起水稻青立病发生，但过量施用会显著降低稻谷产量。与不发病田块相比，发病田块 0~50 cm 土层重金属砷含量增加 2.3~5.6 mg/kg；与不发病植株相比，发病水稻植株总砷含量增加 0.03~0.20 mg/kg；与对照相比，在小麦季随整地施用硫磺并在水稻季随整地施用石灰可降低水稻青立病发病率 20.74%；与种植籼稻品种相比，在水稻青立病易发病田块种植粳稻品种可使发病率显著降低。【结论】绵阳市水稻青立病发生原因为土壤重金属砷、镉和铜含量偏高。苄乙、吡嘧磺隆、二氯喹啉酸和五氟磺草胺 4 种除草剂施用不是水稻青立病的发病原因。在麦稻轮作和秸秆全量还田条件下，在小麦季随整地施用硫磺并在水稻季随整地施用石灰对水稻青立病防治效果显著。     

Activation of repair pathways after neuronal DNA damage induced by bupivacaine

AIM To investigate the activation of related repair pathways after bupivacaine-induced neuronal DNA damage by cDNA gene screening. METHODS The bupivacaine-induced SH-SY5Y neuronal damage and DNA damage model was established. The technique of cDNA microplate array was used to screen the 21 important regulatory factors in the DNA damage repair pathway. Post-analysis of these differentially expressed repair genes for the repair pathway enrichment and distribution was performed. The data were analyzed by GraphPad Prism 6 statistical software to compare differences between groups. RESULTS The viability of SH-SY5Y cells treated with bupivacaine at different concentrations （detected by CCK-8 assay） showed that the IC₅₀ value of bupivacaine was 1.5 mmol/L. The comet assay related index （the comet tail） was increased （P<0.05）， the phosphorylation level of γH2AX protein was increased （P<0.05）， indicating that DNA damage in the SH-SY5Y cells was significantly aggravated after bupivacaine treatment. The results of cDNA microplate assay showed that compared withcontrol group， the differentially expressed genes after bupivacaine treatment were DNA-PKcs， PTEN， NTH1， RAD9， CSB， GADD45， XPD， XPC-HR23B and P53. The analysis showed that these repair genes were mainly concentrated in the following 3 repair mechanisms： base excision repair， nucleotide excision repair， and non-homologous reconstitution. CONCLUSION The repair genes differentially expressed after neuronal DNA damage caused by local anesthetics are mainly concentrated in the pathways of non-homologous end-joining， base excision repair and nucleotide excision repair.     

Development of Eco-friendly and Non-hazardous Weed Control Technology for Lowland Rice by Smothering through LDPE Film

Intensive use of chemical herbicides and pesticides has raised serious concern about their effect on non-target organisms, plants, human bodies and the environment. Hence there is a continuous search for benign, harmless, non-hazardous and eco-friendly technology to control the growth of weeds which compete with crops for water, nutrients, light and space; thus reducing crop yield significantly. An attempt was made to control the weeds through smothering. This controls the weeds by cutting off light from the photosynthetic portion of weed plants by using black polyethylene sheets (LPDE film) which inhibit the top growth. Experiments to control the weeds in a lowland rice field through smothering were conducted in the high rainfall coastal region of eastern India wth eight treatments including smothering and conventional methods like hand/mechanical weeding and herbicides, etc. The treatment of smothering for one week + puddling + transplanting proved to be better than other conventional methods and may replace herbicide and hand/mechanical weeding totally with a better rice yield.     

Morphological disparities in the epidermal and anatomical features of the leaf among wild Brassica juncea populations

In the present article, we investigated the epidermal and anatomical features of 10 wild Brassica juncea populations with different susceptibilities to glyphosate in detail. The characteristics of the leaf surface and anatomy could affect the efficacy of glyphosate uptake in weeds through the influence of its adherence and penetration. Our results showed that herbicide-resistant wild populations generally had greater leaf thickness, adaxial cutin thickness, and trichome density in the upper epidermis, but lower spongy tissue thickness and vascular bundle numbers, as compared with the susceptible populations, suggesting that differences in morphological traits among populations might contribute to their variable response to glyphosate. The possible morphological involvement in the differential susceptibility of wild B. juncea populations to glyphosate also was discussed.     

紫花苜蓿对氟乐灵除草剂的抗性试验

利用氟乐灵除草剂，在苜蓿播种前对土壤进行地下处理，灭除杂草，提高苜蓿产草量。结果表明，苜蓿幼株长势良好，氟乐灵对杂草杀灭率为９０％以上，使用氟乐灵灭草剂成本低，效果好，可在生产中推广应用。     

毕节地区新造林地鼠兔危害状况调查及防控对策

对啮齿类动物鼠兔害的防治.危害调查、标本制作、种类鉴定、生活习性观察,探索有效控制措施.本文着重从森林环境资源的核算评估鼠兔害对新造林地经济损失.     

露地大白菜低温冻害气象指数保险费率厘定方法研究

【目的】为科学厘定露地大白菜低温冻害保险费率提供方法,为其他气象因子指数保险的保险费率厘定提供参考,为政策性农业保险的可持续发展提供助力。【方法】将1957—2018年每年初、终霜冻日期转化为儒历日,计算平均初、终霜冻日期,将平均初、终霜冻日期设定为低温冻害指数保险中的时间起赔阈值,并利用标准差分级法,对起赔阈值设置的合理性进行检验。精确统计大白菜各生长期投入成本,根据灾损率进行加权计算得出赔付比例。通过计算发生概率、灾损率与赔付比例3个因子综合得出露地大白菜低温冻害保险费率,并对种植区域进行加权计算,得出区域内的露地大白菜低温冻害保险费率。【结果】设计了露地大白菜低温冻害气象指数保险中时间和气温起赔阈值的计算方法,并制定了时间起赔阈值的检验方法。设计了低温冻害保险费率3个决定因子发生概率、灾损率和赔付比例的计算方法。【结论】经过检验,将平均初、终霜冻日期设定为丰宁满族自治县地区露地大白菜低温冻害气象指数保险的时间起赔阈值是合理的。露地大白菜在遭受轻、中、重三级低温冻害时的灾损率分别为0.3、0.7和1.0;发芽期赔付比例最高为45%,秧苗期赔付比例最高为75%,莲座期以后赔付比例最高为100%。各乡镇露地大白菜低温冻害气象指数保险费率为2%～3%,经过加权计算得出丰宁满族自治县地区低温冻害保险费率为2.14%。     

Depletion of ascorbic acid derivatives in fish feed by the production process

ABSTRACT:   The depletion of ascorbic acid derivatives in fish feed during the feed processing (extrusion cooking and drying) was studied at five extrusion cooking temperatures and at 85°C for 2 h dryer processing temperature. Three ascorbic acid derivatives were used: L-ascorbyl-2-mono-phosphate Mg (APM), L-ascorbic acid sodium (AAS) and L-ascorbic acid palmitic acid ester (AAP). Samples were collected after drying and ascorbic acid derivatives losses evaluated. APM was found to be quiet stable with an average retention of 88%, but AAS and AAP were unstable and the depletion was very high.