青稞粮草双高新品种藏青27的选育与栽培技术

选育粮草双高型青稞新品种,既是西藏自治区粮食安全保障的要求,也是种植区农户种养结构改善的需要。藏青27以中晚熟高秆大粒丰产型新品种藏青320为母本,用中熟中秆大穗多粒的美国大麦品种做父本杂交,1987年形成杂交组合,2016年通过西藏自治区作物品种审定后推广。该品种在西藏全区多点生产比较示范中,平均产量为326.7 kg/667 m~2,比对照喜拉19号增产15.8%,丰产性较好。本文从选育过程、不同海拔种植地的播种期、播种管理、栽培等方面进行了阐述,以期为该品种的大面积推广提供参考。     

基于茎秆生物力学特性的油菜抗倒调控机制研究

为了应用生物力学特性指标对茎秆抗倒性进行评价，进而指导油菜抗倒栽培，以华杂62和金油杂158为试验材料，基于不同栽培因素下油菜茎秆的弹性模量、弯曲强度、剪切强度及抗倒性，分析了栽培因素对油菜茎秆力学特性指标的影响及其与抗倒性的相关性。结果表明：油菜抗倒性与茎秆的弹性模量、弯曲强度、剪切强度呈显著负相关；随着播期推迟，油菜茎秆的弹性模量、弯曲强度及剪切强度分别减小15.31%、29.16%和13.88%，倒伏指数增大32.18%；随着播种密度增大，油菜茎秆的弹性模量、弯曲强度及剪切强度均呈先增大后减小趋势，而倒伏指数先减小后增大；随着施氮量增加，油菜茎秆的弹性模量、弯曲强度及剪切强度均逐渐减小，而倒伏指数逐渐增大，与施氮量120 kg·hm^-2处理相比，在施氮量为360 kg·hm^-2下，油菜茎秆的弹性模量、弯曲强度及剪切强度分别减小39.43%、19.40%和16.63%，倒伏指数增大16.36%。因此，播期提前、适当增加播种密度、控制氮肥投入，有助于提高油菜茎秆的力学特性强度，从而增强油菜的抗倒伏能力。研究结果可为油菜抗倒栽培调控提供理论依据。     

海贝柱自动晾晒设备设计

针对当前传统人工晾晒海贝柱效率低下、容易造成污染等问题。设计了海贝柱自动晾晒机械,采用阶梯式晾晒生产线对湿海贝柱分级晾晒,多条晾晒生产线分时、高效的工作,机器上方设有遮板以保证晾晒作业不被污染而且不受天气条件的影响。整机采用stm32单片机、传感器等技术实现自动化作业,机器控制系统监测到生产线发生故障或海贝柱出现堆积时会立即停止工作以便于检查故障、减少损失。试验结果表明:机械晾晒不会造成海贝柱内的营养成分的流失,机械晾晒海贝柱的干基含水率达到30%仅需12h,机械晾晒海贝柱能节省大量的干燥时间,显著的提高了晾晒效率,避免了人工晾晒过程导致的二次污染和损失。该研究为海贝柱自动晾晒机械的研制提供了技术参考。     

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。     

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.