不同轮作模式下小麦禾谷孢囊线虫的发生动态和种群密度

轮作是防治小麦禾谷孢囊线虫的重要农业措施,为了明确青海省春麦区不同轮作模式对小麦禾谷孢囊线虫的控制效果,采用田间大区试验法对生产中应用的6种轮作模式进行了研究。结果表明:不同轮作模式下,小麦禾谷孢囊线虫种群密度变化差异极显著,其中小麦与马铃薯、油菜、蚕豆轮作两年或以上能有效降低小麦禾谷孢囊线虫种群密度,土壤中的孢囊量减少39.31%~84.39%,单孢虫口数量减少73.21%~95.35%,虫口密度减少83.76%~97.82%;不同作物间,小麦与马铃薯或蚕豆的轮作效果(虫口密度减少74.39%~79.37%)显著优于小麦与油菜的轮作效果(虫口密度减少67.16%)。在同一地块相同条件下,种植油菜、蚕豆、马铃薯、小麦4种作物,小麦禾谷孢囊线虫均能正常孵化,4月底土壤中的2龄幼虫(J2)量增加,5月上旬达到高峰期,5月中旬开始,土壤中的J2、孢囊量、虫口密度和单孢虫口数量均急剧下降,6月至7月份下降幅度小,趋于稳定;田间空孢囊率于5月中旬至6月中旬急剧增加,7月份趋于稳定,8月份以前,4种作物田禾谷孢囊线虫的孵化动态和种群密度变化趋势一致,8月中旬,小麦田随着新孢囊脱落到土壤中,禾谷孢囊线虫种群密度开始上升,小麦收获后土壤中的孢囊量比播种前增加28.62%,虫口密度增加41.30%;而油菜、蚕豆、马铃薯田土壤中的孢囊量比播种前减少32.27%~48.36%,虫口密度减少70.91%~81.73%,8月中旬至10月份小麦田禾谷孢囊线虫种群密度极显著高于油菜、蚕豆、马铃薯田。     

Bioavailability of suppository acetaminophen in healthy and hospitalized ill dogs

To determine the plasma pharmacokinetics of suppository acetaminophen (APAP) in healthy dogs and clinically ill dogs. This prospective study used six healthy client‐owned and 20 clinically ill hospitalized dogs. The healthy dogs were randomized by coin flip to receive APAP orally or as a suppository in crossover study design. Blood samples were collected up to 10 hr after APAP dosing. The hospitalized dogs were administered APAP as a suppository, and blood collected at 2 and 6 hr after dosing. Plasma samples were analyzed by ultra‐performance liquid chromatography with triple quadrupole mass spectrometry. In healthy dogs, oral APAP maximal concentration (C_MAX=2.69 μg/ml) was reached quickly (T_MAX=1.04 hr) and eliminated rapidly (T1/2 = 1.81 hr). Suppository APAP was rapidly, but variably absorbed (C_MAX=0.52 μg/ml T_MAX=0.67 hr) and eliminated (T_1/2 = 3.21 hr). The relative (to oral) fraction of the suppository dose absorbed was 30% (range <1%–67%). In hospitalized ill dogs, the suppository APAP mean plasma concentration at 2 hr and 6 hr was 1.317 μg/ml and 0.283 μg/ml. Nonlinear mixed‐effects modeling did not identify significant covariates affecting variability and was similar to noncompartmental results. Results supported that oral and suppository acetaminophen in healthy and clinical dogs did not reach or sustain concentrations associated with efficacy. Further studies performed on different doses are needed.     

A novel screening method for rice allelopathic potential: the inhibitory‐circle method

Screening crop accessions for allelopathic activity is of paramount importance for crop allelopathy research. Previous bioassays often did not use a mixed culture of donor and target plants, did not use soil and were not conducted under natural conditions. In this study, we designed an inhibitory‐circle method in which a rice accession (donor plant) and Echinochloa crus‐galli (target plant) were cultured together in paddy soil under natural conditions. First, we determined that the highest allelopathic activity of allelopathic rice accession PI312777 was at the 5‐leaf stage, and the suitable distance of rice seedlings and E. crus‐galli was 12 cm apart. This method was then validated by a field test. A further 40 rice accessions were evaluated for allelopathic activity to E. crus‐galli using this method. Two rice accessions, PI312777 and Taichung Native 1, had highly allelopathic activity to E. crus‐galli (inhibitory rate > 50%), while another accession, Lemont, had non‐allelopathic activity. These experimental results were in accordance with previous studies using direct field experiments. The inhibitory‐circle method integrated three necessary conditions, that is donor and target plants grown together, with soil as the medium and under natural conditions for reliable results. The ‘inhibitory‐circle method’, which combined donor and target plants, soil medium and field conditions, can give reliable results in one step, compared with laboratory screening methods. Also, the ‘inhibitory‐circle method’ gave results in 30‐35 days, thereby substantially reducing the requirements for time, labour and cost.     

罐藏番茄新品种石红9号的选育

石红9号是以3071-3-5为母本,以3072-4为父本配制的中熟、制酱专用罐藏加工番茄一代杂种。自封顶类型,果实深红色,高圆形,平均单果质量82g,抗裂、耐压、耐贮运,可溶性固形物含量4.92%,番茄红素含量154.8mg·kg-1(FW),总糖3.20%,总酸0.27%,干物质5.92%,每667m2产量6500kg左右。已在新疆、内蒙古巴颜淖尔、甘肃张掖、宁夏平罗等地推广种植3600hm2。     

家蚕品种茧层生产效率的调查及相关分析

251个家蚕品种的茧层生产效率平均为10．11％，最高12．19％，最低6．71％。二化性品种较高，一化性和多化性较低。中系二化种最高，平均10．54％，日二化种次之，平均10．39％，欧一化平均9.08％，日一化8．90％，多化平均8．72％。茧层生产效率与茧层量、茧层率、5龄一日茧层量成正相关，达显著或极显著水平；与5龄经过、全龄经过有正相关倾向，但不显著；与虫蛹率、死笼率、全茧量、消化率无一致倾向的相关。还调查了消化率和茧层转换率。     

人参三醇组皂苷对大鼠急性坐骨神经损伤修复相关蛋白表达的影响

研究人参三醇组皂苷(PTS)对大鼠坐骨神经急性损伤蛋白表达的影响。建立大鼠坐骨神经挤压损伤模型,随机分为PTS组,模型对照组及空白对照组,每组各10只大鼠;各组均经腹腔注射给药,PTS组损伤后注射PTS;模型对照组,损伤后注射同剂量生理盐水;空白对照组,不损伤坐骨神经,注射同剂量生理盐水。坐骨神经损伤术后30d,免疫荧光化学染色检测PTS对损伤侧坐骨神经神经丝蛋白(NF-M)、微管相关蛋白-2(MAP-2)、生长相关蛋白(GAP-43)表达的影响,观察PTS对损伤侧神经的影响。大鼠损伤侧坐骨神经NF-M、MAP-2、GAP-43平均光密度表达(9.66±0.99、12.43±1.44、0.344±0.040)与模型对照组(8.21±1.25、11.90±1.14、0.278±0.042)比较有极显著性差异(P0.01)。PTS可促进坐骨神经损伤大鼠NF-M,MAP-2,GAP-43的表达。     

“伊维菌素”注射液对肉牛皮蝇蛆的防治效果观察

牛皮蝇蛆是危害我国畜牧业发展最为严重的寄生虫病之一。本试验将已感染牛皮蝇蛆的171头肉牛为对象,随机分成5组。将伊维菌素注射液分别以高、中、低三种剂量对不同组别的肉牛进行颈部皮下注射治疗和观察,同时注射等体积生理盐水作为阴性对照组,饲喂虫克星粉剂作为阳性对照组进行对比试验。结果显示,0.2 mg/kg体重(中剂量组)为伊维菌素皮下注射的最佳剂量,对皮蝇蛆的治愈率达97.82%(45/46),而以0.2 mg/kg体重口服虫克星粉剂的对照组治愈率达60.71%(17/28),且统计分析差异显著(P0.05)。试验表明,中等剂量的伊维菌素注射液对牛皮蝇蛆的防治安全可靠且效果显著,为临床治疗肉牛皮蝇蛆提供理论参考。     

不同添加剂对紫花苜蓿拉伸膜裹包青贮饲料品质的影响

为明确葡萄糖、红糖、果渣对紫花苜蓿拉伸膜裹包青贮饲料青贮品质的影响,探明最适合添加于紫花苜蓿裹包青贮的有机添加剂,按照紫花苜蓿原料重量的0.2%、0.4%、10%分别添加葡萄糖、果糖、果渣进行90 d青贮。结果表明:添加葡萄糖可保留紫花苜蓿中更多的干物质,有效提高青贮饲料中的乳酸含量,降低乙酸和丙酸含量;添加红糖不利于青贮饲料pH值的降低和乳酸积累,能产生较高的氨态氮、乙酸和丙酸含量;添加果渣虽然可以降低青贮饲料的pH值,但会造成显著的粗蛋白损失。综合分析认为,添加葡萄糖对提高紫花苜蓿拉伸膜裹包青贮饲料青贮品质效果较好。     

戊唑醇分子印迹传感器制备及其农药残留检测的电学传感机理分析

以甲基丙烯酸为功能单体,戊唑醇(tebuconazole,TEB)为模板分子,乙二醇二甲基丙烯酸酯为交联剂,应用电化学聚合法制备了分子印迹电化学传感器(TEB-MIP/F-CNTs/GCE)。利用循环伏安法(cyclic voltammetry,CV)和交流阻抗法(electrochemical impedance spectroscopy,EIS)对新型传感器进行了表征,并用差分脉冲伏安法(differential pulse voltammetry,DPV)考察了新型传感器对戊唑醇的检测性能。结果表明:戊唑醇分子印迹电化学传感器具有一定特异性;传感器表观表面积比裸电极显著提高;新型传感器具有良好的印迹效果,相较于其他结构类似的三唑类化合物(如苯醚甲环唑),TEB-MIP/F-CNTs/GCE对戊唑醇表现出高效的识别能力,具有专一性和强选择性,且在C_(TEB)≤2.0×10~(-6)mol/L范围内传感器峰电流与C_(TEB)存在定量关系;数据模拟分析得到传感器的电学阻抗谱等效电路模型为R_1(CPE_1(R_2(CPE_2(R_3)))),计算各电极/传感器的等效电路中各元件参数,证明该模型能有效地模拟传感器检测戊唑醇的传感机理。该研究结果可为三唑类农药残留仿生免疫检测方法的建立提供技术支撑。