Effects of peach branches returning on autotoxins and microbes in soil and tree growth of peaches

Aims This study aimed to investigate the effects of branch returning on the growth of peach (Amygdalus persica "Chunmei/Maotao") saplings, soil enzyme activity, and soil contents of phenolic acids and amygdalin, thereby providing scientific evidence against the application of branch returning for peach trees. Methods One-year-old potted peach tree (Amygdalus persica "Chunmei/Maotao") was used in this study with four agricultural treatments applied, including soil coverage by fragmented peach tree branches (fragment treatment;1.5 and 22.5 g·kg^-1) and applying leachate solutions of peach tree branches to soil (leachate treatment; 1.5 and 22.5 g·kg^-1). No branch addition was used as control (CK). Solid phase extraction, high performance liquid chromatography (HPLC), biological high-throughput sequencing was used to determine the content of autotoxic substances, and microbial community structure in soil. Soil coverage and leachate solution treatments of 30 g and 450 g branches applied to the peach trees were described as 1.5 and 22.5 g·kg^-1, respectively in this paper.Important findings Compared with CK, the phenolic acid and amygdalin contents significantly increased after both fragment and leachate treatments in high quantities (22.5 g·kg^-1). Soil microbial community structure altered in both treatments, with the proportion of fungi (particularly Agaricomycetes, Tubeufia and Cystofilobasidiaceae) increased significantly and bacteria decreased accordingly. Invertase activity in both high-quantity treatments exceeded that in the CK significantly. The activity of catalase and urease was higher at first and then decreased relative to CK under high-quantity fragment and leachate treatments. Specifically, the effect of leachate treatment on enzyme activity was higher than the fragment treatment in the short term. Chlorophyll content, ground diameter (diameter of 5 cm from the ground) growth and net photosynthesis rate of plants were lower in high-quantity fragment and leachate treatments than those in CK, with earlier retardation of new shoot growth. We observed an increase in soil phenolic acids and enzymes in treatments in normal pruning quantity, while no inhibition effect was found on the tree growth. In conclusion, autotoxins (such as phenolic acid and amygdalin) inhibited the growth of peach trees both directly and indirectly through changing soil enzyme activity and microbial community.     

探究黄热病毒NS1蛋白在感染早期的诊断价值

为了探讨黄热病毒(Yellow fever virus,YFV)非结构蛋白1(Nonstructural protein 1,NS1)在感染早期的诊断价值。颅内注射YFV-17D感染乳鼠,每日处死1窝,收集抗凝血。Vero细胞和C6/36细胞感染YFV-17D病毒后,每隔12h收集培养上清。分别采用荧光定量PCR和基于YFV NS1多克隆抗体的双抗体夹心酶联免疫(Enzyme linked immunosorbent assay,ELISA)方法检测感染后乳鼠血液、C6/36和Vero细胞上清中YFV的扩增情况和NS1蛋白的分泌规律。乳鼠感染YFV-17D后第2d在血清中即可检测到YFV NS1,第3d血液中检测到YFV核酸。敏感细胞株在感染YFV-17D后第36h培养上清中可检测到YFV NS1,而48h后才能检测到YFV核酸。YFV NS1蛋白具有作为YFV感染早期的诊断靶标的潜在价值。     

黑鹅膏菌（Amanita fuliginea）毒素的HPLC初步分离鉴定

本文了用反相高效液相色谱法（ＨＰＬＣ）分离黑鹅膏实体内几种鹅膏毒素的结果,采用Ｃ１８液相柱,以不同浓度的０．０２ｍｏｌ／Ｌ乙酸铵－乙腈混合液为流动相,从黑鹅膏子产体中分离并鉴定出了６种毒素,每公斤干重含量分别为（ｍｍｏｌ）：α－毒伞肽：５．１９ｍｍｏｌ;β－毒伞肽;１．１７ｍｍｏｌ;ｐｈａｌｌｏｉｄｉｎ;１．５ｍｍｏｌ;ｐｈａｌｌａｃｉｄｉｎ;０．４０ｍｍｏｌ;ｐｈａｌｌｉｓｉｎ;０．２６ｍｍｏｌ     

番木瓜环斑病毒YsCP基因的序列分析和植物表达载体的构建

用双脱氧链终止法分析了克隆的番木瓜环斑病毒（PRV）Ys株系外壳蛋白（CP）基因的序列,结果表明YsCP基因全长858nt。对PRV国内外16个株系或分离物CP基因的比较发现,YsCP基因与国内株系或分离物CP基因的同源性较高（94．44％～97．68％）,而与国外株系或分离物CP基因的同源性较低（88．88％～92．70％）。CP基因之间的差异主要靠近基因5’端,特别是在YSCP基因第63nt后连续缺失6nt,SmGTHAI和SRI的CP基因也在此处缺失3nt。将YsCP基因插入中间质粒pRokⅡ的CaMV35S启动于和nos终止序列之间形成CP基因的植物表达载体pRPCY,通过三亲交配使pRPCY进入农杆菌LBA4404,与其中的pAL4404构成双元载体系统。     

番茄（Lycopersicon）的化感作用研究

采用室内生测、室外盆栽和水培相结合的研究方法,以多种受体品种来探讨番茄 的化感作用．结果表明,番茄植物不仅具有自毒作用,番茄植株的水提液对黄瓜、萝卜、生 菜、白菜、包心菜的幼苗生长均有显著的抑制作用;番茄植株的挥发物对黄瓜的生长具有 明显的抑制作用,但对绿豆、白菜、生菜及番茄自身的幼苗生长则无明显的影响;番茄移苗 后４０ ｄ之内,其根分泌物对黄瓜生长有明显抑制作用,但对生菜作用不明显认为自毒作 用是造成番茄连作障碍的原因之一,指出番茄种植应采用轮作方式,水培或大棚种植番茄 时,应避免与黄瓜间种．     

口泰含漱液对控制菌斑和牙龈炎的疗效分析

本研究采用双盲随机对照法观察口泰含液对牙龈炎及控制菌斑的疗效。结果显示：实验组的牙龈指数,龈沟出血指数及菌斑指数以在含漱５天后均有明显的改善,且与对照组的比较也有明显的差异。     

几种不同鹅膏菌毒素对真核生物RNA聚合酶Ⅱ抑制作用的比较研究

用鹅膏菌属（Amanita）含α-毒伞肽的毒素粗提液培养新鲜绿豆,结果在36小时后,各种不同毒苗的毒素粗提液培养的绿豆生长情况有明显不同,用紫外吸收法测定蛋白质含量,发现毒素粗提液培养的绿豆细胞中蛋白质含量比蒸馏水培养的有明显下降,这表明α-毒伞肽的作用机理的确是通过抑制RNA聚合酶Ⅱ而寻致蛋白质合成减少。     

我国韭菜主产区韭菜迟眼蕈蚊田间种群的抗药性监测

【目的】建立韭菜迟眼蕈蚊Bradysia odoriphaga Yang et Zhang对10种常用药剂的敏感基线,并对4省7个主要韭菜产区的田间种群进行6种常用杀虫剂的抗药性水平监测。【方法】采用胃毒触杀联合毒力法对韭菜迟眼蕈蚊3龄幼虫进行室内生物测定。【结果】建立了敏感品系对新烟碱类、有机磷类、菊酯类、昆虫生长调节剂类、吡咯类药剂的敏感基线。对7个地区的田间韭菜迟眼蕈蚊种群监测结果表明:其对有机磷类药剂均产生了抗药性,其中河南郑州种群对毒死蜱和辛硫磷产生了极高水平抗性;河南郑州种群对高效氯氰菊酯产生了中等水平抗性,其他各地区均处于敏感状态;大部分种群对新烟碱类药剂处于低等或中等水平抗性,但山东李坡种群对噻虫嗪产生了高水平抗性。【结论】本文建立的韭菜迟眼蕈蚊对10种杀虫剂的敏感基线及抗药性监测数据为抗性治理提供一定参考。     

三种植物精油对家蝇成虫的熏蒸活性

【目的】探究香樟Cinnamomum caphora果实精油、天竺桂Cinnamomum pedunculatum叶精油和龙柏Sabina chinensis var.chinensis叶精油对家蝇Musca domestica成虫的熏蒸活性,比较这3种植物精油以及混配精油对家蝇的毒力效果,为植物源灭蝇剂的开发提供理论依据。【方法】利用水蒸汽蒸馏法提取植物精油,采取三角瓶密闭熏蒸法测试植物精油及其混剂对家蝇5日龄成虫的熏蒸毒性和击倒作用。【结果】3种植物精油对家蝇的LC50值(致死中浓)分别为5.28,16.86和14.54μg/cm3。LC90熏蒸剂量下,对家蝇的KT50值(击倒中时)分别为12.03,16.56和13.37 min。天竺桂叶精油和龙柏叶精油混配后对家蝇有增效作用,二者的LC50值配比为9∶1时,增效作用极为显著,共毒系数高达367.95。【结论】香樟果实精油对家蝇成虫有很好的熏杀和击倒作用,龙柏叶精油次之,天竺桂叶精油效果最差。天竺桂叶精油和龙柏叶精油混配后对其对家蝇成虫的熏蒸毒性有增效作用。3种植物精油具备开发环保灭蝇剂的潜力,可深入研究。     

抗五步蛇毒血清致血清病30例临床分析

目的探讨抗五步蛇毒血清所致血清病的临床特点,总结其治疗方法及可预防性手段。方法回顾性分析1447例使用抗五步蛇毒血清治疗的毒蛇咬伤患者的临床资料,其中30例患者在治疗后出现血清病症状,采用抗变态反应等治疗。结果 30例患者均治愈,住院治疗时间1~8天,平均3.53天。结论抗五步蛇毒血清致血清病患者及时给予抗变态反应治疗,其预后良好,按规范用药以及临床中早发现并及时处理是防治关键。