异硫氰酸丙烯酯毒杀松材线虫作用机制初步研究

对异硫氰酸丙烯酯毒杀松材线虫作用机制进行了初步研究。测定了其对线虫虫体形态、运动行为、体内总糖和蛋白质含量的影响,以及处理前后线虫体内过氧化氢酶(CAT)、乙酰胆碱酯酶(AChE)和谷胱甘肽-S-转移酶(GST)活性变化。结果表明:经异硫氰酸丙烯酯处理后的松材线虫虫体形态严重扭曲,运动形态出现由正常的S形变化为多节弯曲和螺旋状卷曲等异常状况,线虫行动随时间的推移变得迟缓,最终呈C形、新月形或直接死亡。随着异硫氰酸丙烯酯处理质量浓度的增大,线虫体内总糖和蛋白质含量显著上升,糖和蛋白质的代谢发生紊乱;线虫体内CAT、AChE和GST活性显著降低,且均低于对照组,表明线虫体内氧化和抗氧化作用失衡;细胞受到极大的影响,神经系统遭到破坏,解毒能力明显降低。研究结果可为研究利用异硫氰酸丙烯酯作为植物源杀线虫剂提供依据。     

秀珍菇原基形成相关基因PpFBD1的克隆与表达研究

前期研究中通过对秀珍菇经低温诱导后不同发育阶段样本进行转录组测序及差异表达基因分析发现,ID为Cluster-6377.64510的基因(命名为PpFBD1)在原基形成前期的样本中高表达。为进一步了解分析其表达特性及功能,根据转录组测序结果设计特异性引物,利用RT-PCR技术从秀珍菇中克隆获得了该基因的cDNA全长。该基因由342个核苷酸组成,编码一个由113个氨基酸组成的蛋白,蛋白相对分子质量约11 ku。进化树分析显示,PpFBD1编码蛋白与糙皮侧耳hydrophobin1编码的疏水蛋白亲缘关系最近。Gene Ontology功能分析表明,PpFBD1主要参与真菌类细胞壁的合成。荧光定量RT-PCR检测显示,该基因在菌丝体经低温诱导后恢复至室温阶段(原基形成前期)表达量最高,这表明其可能参与调控秀珍菇原基形成过程。本研究结果为阐明秀珍菇原基形成机制提供参考。     

减氮条件下密度对望两优361产量的影响

为探索减氮条件下密度对望两优361产量的影响,2018年在马庙镇进行了该试验。试验结果表明：怀宁县单季稻施肥量应为：N:P:K=13.5:5.4:10.8。在此施肥量的基础上： 1.5万穴/667m_²为最佳移栽密度。     

鸡流行性腹泻病原的分离鉴定及特性研究

用胰蛋白酶处理发病鸡的粪便和肠内容物，接种Marc145细胞，盲传数代后，从山东不同地区发生流行性腹泻的鸡群中分离到轮状病毒，并对分离的轮状病毒的生物学特性和理化特性进行了部分研究。结果表明病毒粒子的形态呈车轮状、大小为70-80nm；其病毒基因组的电泳图谱为5：1：3：2；病毒在Marc145细胞上传到第9代时的TCID50为10^-4.62／0．1mL；该分离株病毒对氯仿、乙醚有抵抗力；对pH3．0处理60min稳定；50℃ 30min能使其感染力下降10^2；1mol／L MgCl2不能增强其对50℃ 60min的抵抗力。动物回归试验中接种两周龄SPF鸡，24h后陆续发病，表现为持续性水样腹泻，与自然发病相同；剖检可见病鸡脱水、小肠内有大量的液体和气泡、肠粘膜变薄；组织学变化为肠绒毛上皮坏死、脱落，绒毛平均长度减少而隐窝深度增加，固有层中淋巴细胞浸润。其临床症状及病理组织学变化与自然发病相同。因此确定发生在山东鸡流行件腹泻的病原为轮状病毒．     

聚丙烯酰胺凝胶电泳法鉴定禽呼肠孤病毒

从感染禽呼肠孤病毒的细胞中,以SDS和酚提取病毒核酸,通过聚丙烯酰胺凝胶电泳(PAGE)法将分节段的核酸分开,经银染色显示,呈3-3-1-3分布,此法可用于禽呼肠孤病毒的快速检测、鉴定。同样方法未能使传染性法氏囊病毒核酸显示。     

一类耗散非线性波动方程初边值问题整体解的存在与非存在性

本文考虑一类耗散非线性波动方程的初边值问题。用半(?)方法和先验估计论证了该问题小初值下在时间大范围的可解性、唯一性;并用凸性方法证明了(?)当条件下该问题的解在有限时间内发生爆破现象。     

Evaluation of abomasal outflow diversion as an experimental model of hypochloremic, hypokalemic metabolic alkalosis in lactating cows.

Four adult, lactating dairy cows were subjected to diversion (loss) of gastric contents through a T-shaped cannula placed in the cranial part of the duodenum just distal to the pylorus. Diversion was continued for 10 to 12 hours, at which point the cows were very weak and depressed. The volume of effluent during this period ranged from 37.3 to 46.8 L, with the largest volume being produced during the first four hours. All cows became dehydrated, with mean packed cell volume and total plasma protein concentration increasing 30% and 19.6%, respectively, but with only a slight increase in plasma creatinine concentration. Plasma Cl- concentrations decreased from a mean of 97.3 mEq/L at the beginning of diversion to a mean of 87.2 mEq/L at eight hours. This was followed by a plateau or slight increase in concentrations over the final hours of diversion. Plasma K+ concentration followed a similar pattern, decreasing from a mean of 3.9 mEq/L to a mean of 2.94 mEq/L at six hours, followed by increasing values until termination of diversion. No changes in plasma Na+ concentration were noted, except for a mild decrease in one cow. Plasma calcium concentrations decreased significantly, reaching 6.6 +/- 0.6 mEq/L at the end of diversion. Venous pH, plasma HCO3- concentration, and plasma base excess concentration increased during the first four to eight hours of diversion, followed by a gradual decline. Although a mild hypochloremic metabolic alkalosis resulted from diversion of abomasal outflow in all cows, substantiated by a mild increase in plasma strong ion difference, the changes observed were not as great as expected.(ABSTRACT TRUNCATED AT 250 WORDS)     

荔枝果实发育过程中细胞分裂素的变化

荔枝果实中含有玉米素、二氢玉米素和二氢核糖基玉米素。果实发育过程中细胞分裂素（ＣＴＫ）含量的动态是：谢花后两周内含量最高，然后下降并稳定在低水平。用外源６一卞基氨基嘌呤（６一ＢＡ）处理，仅在果实发育初期有明显保果作用。果实采后贮藏期间ＣＴＫ含量稳定在低水平；贮藏前用６一ＢＡ处理，能延迟果实衰老，提高果品质量。     

茶多酚(TP)对家禽免疫功能的研究

选用14日龄健康的海佩科内用仔鸡48羽,随机分成试验(24羽)和对照(24羽)两组.试验组在饲粮中添加0.25％的茶多酚(TP),研究TP对鸡免疫功能的作用.试验结果表明,TP对自然感染法氏囊病鸡,有明显提高(p<0.05)鸡血液中红细胞C_(3b)受体和免疫复合物的含量及保护鸡脾脏正常的免疫功能,同时也发现TP对公母鸡法氏囊的重量有不同影响.本试验表明,TP具有提高家禽免疫功能的作用.     

Use of netting and whitewash spray to protect papaya plants against Nivun Haamir (NH)-dieback disease

A disease causing the decline of papaya (Carica papaya) plants was noticed in the Jordan Valley in 1982. The disease caused severe yellowing of the upper leaves and dieback of the apex. The disease was not transmissible mechanically and continued efforts to associate viruses and viroids have so far been unsuccessful. Epidemiological observations suggested that the disease is airborne and probably caused by a mollicute. In order to test this hypothesis, plots were covered by an insect-proof net and with white nets providing 15, 30 and 50% shade. The 30%, 50% and insect-proof nettings provided complete protection, and the 15% netting reduced disease incidence to <2%, compared with>37% in the uncovered control plot. Spraying plants at weekly intervals with a commercial whitewash solution was also found to be effective in reducing disease incidence. The advantages of using a range of netting field treatments as a simple means for obtaining information on the epidemiological nature of a new disease are described.