硫酸二甲酯对白花泡桐丛枝病幼苗形态变化及DNA碱基序列的影响

利用巢式PCR和SSR技术研究了0,15,25,50,75,100,125,150 mg·L-1的硫酸二甲酯(DMS)对白花泡桐幼苗形态、植原体和DNA碱基序列的影响.结果表明,15 mg· L-1DMS处理3h可使丛枝病幼苗转变为形态上健康幼苗,但其幼苗内仍有丛枝病植原体的存在;25～125 mg· L-1 DMS处...     

盐酸阿苯达唑亚砜对照品候选物纯度检测方法的建立

以盐酸阿苯达唑亚砜原料为基础,通过反复提纯,得到盐酸阿苯达唑亚砜对照品候选物,该候选物经过熔点,薄层色谱法（TLC）和高效液相色谱法检测,初步确认符合对照品的要求,经过高效液相色谱检测,采用面积归一化法计算其纯度不小于99.5%。该方法的建立为盐酸阿苯达唑对照品进一步研究提供了帮助。     

吡咯伯克霍尔德菌WY6-5的溶磷、抑菌与 促玉米生长作用研究

【目的】筛选兼具高效溶磷和抑菌作用的微生物,检测其溶磷效果和抑菌活性,鉴定抑菌代谢产物,并分析筛选微生物对植物生长的作用,为新型多功能抑菌微生物菌肥的研发提供材料。【方法】采集信阳毛尖茶车云山茶厂百年龄茶树根际土壤,稀释后涂布难溶性无机磷或难溶性有机磷培养基表面,培养后检测溶磷活性,测定溶磷圈直径,筛选具有高效溶磷作用的微生物,进行后续溶磷效果分析。高效溶磷菌WY6-5接种于培养液和土壤中,检测不同培养时间下,可溶性磷含量的变化规律,分析菌株WY6-5的溶磷活性;玉米盆栽土壤中接种菌株WY6-5菌液,种植27 d后分析玉米植株长势,检测溶磷菌WY6-5对苗期玉米生长的影响;采用双皿对扣培养法,验证菌株WY6-5产挥发性物质的抑菌作用,检测其对不同病原真菌的广谱抑菌效果,气相色谱串接质谱（GC-MS/MS）分析挥发性代谢物质,鉴定主效抑菌成分。【结果】筛选到3个兼具有降解难溶性无机磷和有机磷作用的微生物菌株,尤以菌株WY6-5溶磷效果最优。培养基培养条件下,对难溶性无机磷的溶解直径达2.3 cm,溶磷圈直径与菌落直径比为4.6;对难溶性有机磷溶解直径3.6 cm,溶磷圈直径与菌落直径比达7.2。表型观察、生理生化鉴定和系统发育树分析表明,菌株WY6-5为乳白色细菌,16S rRNA序列与Burkholderia pyrrocinia CIP 105874和Burkholderia stabilis CIP 106845两个菌株的同源性最高,进化树中聚成独立一支。另外,WY6-5与Burkholderia pyrrocinia具有高度相同的生理生化反应结果。因此,本研究将WY6-5鉴定为吡咯伯克霍尔德菌（Burkholderia pyrrocinia）。WY6-5在液体培养和土壤中均具有较好的溶磷活性,20 d培养时间内,液体培养液中磷含量最高达520.4 mg·L ^-1,为对照组176倍;土壤试验3—20 d期间,WY6-5处理组可溶性磷含量均高于对照组,且在盆栽试验中,能高效促进苗期玉米植株的生长,处理组叶长、叶宽、叶片数、茎粗、株高、鲜重等指标显著优于对照组;同时,菌株WY6-5还可产生挥发性抑菌物质,高效广谱抑制8种重要病原真菌的生长,抑菌率最高达100%,经GC-MS/MS检测发现,挥发性物质含有一种主效抑菌物,相对丰度达97%以上,鉴定为二甲基二硫。 【结论】吡咯伯克霍尔德菌（Burkholderia pyrrocinia）WY6-5分离自茶树根际土壤,在培养基、培养液和土壤环境下,均具有高效的溶磷效果,将难溶性的无机磷转化为植物可吸收的可溶性磷,并促进苗期玉米植株的生长;同时该菌还可产生挥发性抑菌物质二甲基二硫,高效抑制8种重要植物病原真菌的生长,抑制率最高达100%。菌株WY6-5兼具有提升土壤磷肥力、促进植物生长和和抑制真菌病害等多种重要作用,具有较好的生物学功能。     

二甲基硫醚氧化菌的分离鉴定及其对猪粪堆肥的影响

从污水处理厂活性污泥中分离得到一株二甲基硫醚(DMS)氧化菌AM2,经16S rDNA检测鉴定其为那不勒斯硫杆菌(Thiobcillus neapolitanus)。AM2的最适生长温度为30℃最适pH为7.0。以猪粪和秸秆粉为原料进行肥料堆肥试验,通过检验菌株AM2对堆肥过程中DMS排放量、堆肥温度、可培养微生物和酶活性的影响,来探究菌株AM2对堆肥的影响。结果表明:接入菌株AM2的实验组DMS释放量显著(P0.05)少于对照组,在30 d的实验中有20 d减少60%以上;显著提高了(P0.05)可培养微生物数量,同时将物料温度高于50℃的天数延长至13 d;实验各组的脲酶、脱氢酶、过氧化氢酶、蛋白酶和纤维素酶酶活都显著高于对照组。综合判断,菌株AM2能够有效降低堆肥过程中DMS的排放量并促进肥料腐熟。     

完全不渗透膜对熏蒸剂防治土传病虫害的影响

完全不渗透膜(TIF膜)对熏蒸剂具有很好的阻隔性,但对熏蒸剂防治土传病虫害的影响还不明确。测定了TIF膜对二甲基二硫、棉隆及1,3-二氯丙烯防治黄瓜土传病害、黄瓜长势、产量及收入的影响,结果表明,在熏蒸剂低用量时,覆盖TIF膜相对PE膜能显著提高熏蒸剂对土壤根结线虫(Meloidogyne spp.)、疫霉菌(Phytophthora spp.)和镰刀菌(Fusarium spp.)的防治效果;并且熏蒸剂低用量时覆盖TIF膜后的产量与熏蒸剂高剂量时覆盖PE膜的产量无显著差异。应用TIF膜可以显著降低熏蒸剂用量,且不影响防治效果,同时也降低了熏蒸剂挥发对施药人员造成的危害,所以TIF膜是有前景的土壤消毒专用膜。     

Cholinergic Activity of Selected Methanesulfonate Insecticides. A Pharmacological Profile

Three previously reported methanesulfonate insecticides, 6-isobutylthio-2-pyridyl methanesulfonate ( I ) and its sulfoxide ( II ) and sulfone ( III )analogues were examined in two insect species Lucilia cuprina and Blattella germanica and in tissues from vertebrates. The results of B. germanica tests and cholinesterase assays confirmed the insecticidal activity of the compounds, with cholinesterase inhibition being the most likely mode of insecticidal action. The inactivity of the sulfide I and sulfoxide II in vertebrate in-vitro studies may indicate that conversion, in vivo, of the sulfide and sulfoxide methanesulfonates to the sulfone ( III ) is a requirement for activity. In mouse toxicity tests, matching high toxicity was observed for the alkylthio-, alkylsulfoxy- and alkylsulfone analogues indicating fast metabolic oxidation of the injected alkylthio- and alkylsulfoxy-compounds. However, in in-vitro tissue tests, the sulfone, although active, did not exhibit the characteristic pharmacological profile of the standard acetylcholinesterase inhibitor, physostigmine. The sulfone demonstrated a mixed action, with indications that it acts as an inhibitor of specific cholinesterase isozymes, or that it may modify responses at cholinoceptors.     

盐酸阿苯达哩亚砜化学结构分析

建立了药物盐酸阿苯达唑亚砜的化学结构确证方法.通过高效液相色谱(HPLC)测定盐酸阿苯达唑亚砜纯度,采用紫外光谱(UV)、红外光谱(IR)、核磁共振(NMR)以及质谱(MS)等分析方法对盐酸阿苯达唑亚砜样品进行了结构测定.结果确证盐酸阿苯达唑亚砜的结构为[5-(丙亚砜基)-1H-苯并咪唑-2-基]氨基甲酸甲醋盐酸.本方...     

Antioxidant potency of white (Brassica oleracea L. var. capitata) and Chinese (Brassica rapa L. var. pekinensis (Lour.)) cabbage: The influence of development stage,cultivar choice and seed selection

The accumulation of total phenols (TP, Folin-Ciocalteu method) and total flavonoids (TF, colorimetric assay with AlCl₃) and the evolution of antioxidant capacity (FRAP assay, DPPH and ABTS radical scavenging assays) have been monitored in juices of Croatian white cabbage (Brassica oleracea var. capitata) cultivars Vara?dinski and Ogulinski, as well as Chinese cabbage (Brassica rapa var. pekinensis), at various developmental stages. Measurements were performed every four weeks, starting from planting to full maturity, throughout the course of eight months. In the first 8–12 weeks, the TP and TF contents as well as antioxidant capacity increased significantly in all analyzed juice samples and in most even doubled. This rapid increase was followed by a gradual decrease in values derived from all assays, over the course of 12–30 weeks, to the final values which were in all cases lower than the values measured at week 4. The results also point to significant variability in TP and TF contents and antioxidant capacity at the fully mature stage between white and Chinese cabbage juices and between juices extracted from cultivars Ogulinski and Vara?dinski.