滴灌条件下地膜覆盖对玉米田间土壤水热效应的影响

水热条件是影响作物生长和发育的重要因素之一,通过田间试验研究了有膜滴灌和无膜滴灌对玉米的土壤水分和温度的变化。结果表明:在玉米生长前期,有膜滴灌0~20cm土层的含水率较无膜滴灌高出6.4%,差异显著(p0.05),但在30~100cm土层,有膜滴灌土壤含水率却比无膜滴灌低6.1%~7.54%,差异显著(p0.05)。玉米生育期前期(5-6月),覆盖地膜比无膜措施平均温度高0.4~4.1℃;种植后30d,覆盖地膜处理在5~10cm土层的日较差显著高于无膜处理,但其他土层差异却不显著,可见地膜覆盖在玉米生育期前期可以增加土壤浅层温度,提高土壤表层含水率,为玉米的生长发育提供了良好的水热条件。     

Anatid herpesvirus 1 CH virulent strain induces syncytium and apoptosis in duck embryo fibroblast cultures

Anatid herpesvirus 1 (AHV-1) CH virulent strain was first isolated from an infected duck and it was found that this virus strain could induce cytopathic effect (CPE) in duck embryo fibroblast (DEF). Following AHV-1 infection, DEF showed morphological changes such as cell rounding, improved refractivity and detachment from the culture surface. However, its pathological characteristics were not adequately known. Related studies were performed and the results showed that syncytium formation could be observed as the other type of CPE in AHV-1 infection. Hematoxylin-eosin staining and 4’, 6-diamidino-2-phenylindole (DAPI) staining of infected DEF were each used to visualize the shape and distribution of chromatin within nuclei and nuclear fragmentation was observed. Chromatin condensation and margination, as well as formation of apoptotic bodies were observed by transmission electron microscopy (TEM). DNA ladder formation was detected in AHV-1 infected cells and apoptosis of the infected DEF was also detected by flow cytometry analysis of Annexin V-FITC/PI staining method. Therefore, it was suggested that AHV-1 virulent strain can induce syncytium and apoptosis in DEF. Syncytium formation and apoptosis observed in this study may contribute to the elucidation of AHV-1 pathogenesis.     

杂交稻抗二化螟的胞质遗传效应分析

以一套6种细胞质的同核异质广亲和不育系和两套同质(野败型和印水型)异核不育系与恢复系蜀恢162和密阳46配组的F1为材料，测定二化螟的幼虫存活率、幼虫体重和田间水稻枯心率，分析了不育系的细胞质、细胞核和质核互作对二化螟抗性的遗传效应。结果表明，二化螟幼虫在同核异质不育系的矮败型“国广2A”、D型“国广4A”、印水型“国广5A”和K型“国广6A”上的体重显著低于在野败型“国广1A”和冈型“国广3A”上的；在国广4A和国广5A上的枯心率(12.9%和14.1%)显著低于在其他同核异质不育系上的。水稻枯心率在野败型和印水型同质异核不育系的2种不育系之间均表现出显著差异。同核异质不育系和印水型同质异核不育系对二化螟存活率没有细胞质效应和质核互作效应。同核异质不育系的质核互作效应(47.1%)和细胞质效应(29.4%)是影响幼虫体重的主要因素；细胞核效应(76.0%)、细胞质(12.1%)和质核互作效应(10.4%)都影响着水稻枯心率。野败型同质异核不育系的细胞核效应(78.5%)是影响幼虫体重的主要因素，其次是细胞质效应(17.7%)；枯心率受到细胞核效应(58.5%)和质核互作效应(35.7%)的影响。印水型同质异核不育系影响幼虫体重和枯心率的质核互作效应分别是26.5%和66.9%；影响幼虫体重的还有细胞核效应(50.7%)和细胞质效应(21.9%)。     

杀螨剂“克螨特”亚致死剂量对朱砂叶螨实验种群生命参数的影响

为了科学合理地使用桑园杀虫剂,采用Jackkn ife统计推断技术,在16 L、(30±1)℃、RH 75%±10%,8D、(20±1)℃、RH 65%±15%的条件下,对寄主为桑树的朱砂叶螨种群水平上的亚致死效应进行了研究。朱砂叶螨成螨经杀螨剂“克螨特”亚致死剂量(60.83 mg/L)处理后,成螨寿命降低,雌螨总产卵量显著低于对照组;处理组内禀增长率(0.272 0±0.007 5)也显著低于对照组(0.338 6±0.005 5)。     

CT—43乳剂防治几种蔬菜害虫的应用效果初报

应用CT—43双毒乳剂防治小菜蛾,菜青虫和豆荚螟有较好的防治效果。以500倍稀释液防治菜青虫的平均防效为93.9％,防治小菜蛾的平均防效为84.8％,防治豆荚螟的平均防效为83.2％,对棉铃虫的防治效果为86.5％。防治效果受虫龄和气温的影响较大。CT—43双毒乳剂对斜纹夜蛾高龄幼虫防治效果欠佳。     

辽宁大凌河河滩地生态修复模式初步研究

以杨树纯林、杨树-沙棘混交林、紫花苜蓿草地为对象,对大凌河河滩地进行植物生态修复模式研究,结果表明:杨树纯林林地的土壤年风蚀量仅为0.21 kg·m~(-2),杨树-沙棘混交林林地为0.25 kg·m~(-2),紫花苜蓿草地为0.30 kg·m~(-2),而对照河滩耕地高达1.69 kg·m~(-2)。3种试验地的土壤年风蚀量均值分别较对照减少了1.48 kg·m~(-2)、1.44 kg·m~(-2)、1.39 kg·m~(-2)。植物生态修复效果显著。     

腐霉利在水溶液中的光化学降解研究

研究了3种浓度的腐霉利在3种光源下的光化学降解途径,并考察了溶液pH、硝酸盐和H2O2对腐霉利水溶液光化学降解的影响。结果表明,在3种光源下,腐霉利水溶液的光解符合一级动力学反应。腐霉利的光解速率在紫外灯下是高压汞灯下的近2倍,其半衰期在高压汞灯下为43.6 min,在紫外灯下仅为28.2 min;以高压汞灯为光源,在浓度2～8 mg.L-1范围内,腐霉利的光解速率与其初始浓度呈负相关;随着溶液pH的增大,腐霉利的光解速度加快;硝酸盐对腐霉利的光解表现为光猝灭效应;而H2O2对腐霉利的光解有显著的光敏化作用。     

杂交小麦复合型种衣剂的生理效应研究

研究了复合型种衣剂包衣处理对杂交小麦种子萌发和幼苗生长的生理效应。结果表明：杂交小麦复合型种衣剂能提高杂交小麦的实验室发芽率和田间出苗率,增强种子的α-淀粉酶活性,增加幼苗的干物质重量,提高叶绿素α、叶绿素b及总叶绿素含量,提高幼苗的根系活力、可溶性蛋白质含量和可溶性糖含量,苗足苗壮,分蘖数增加,对杂交小麦的种子萌发和幼苗的生长有明显的促进作用。     

Experimental Analysis of the Behavior of Steel Plate-masonry Composite Wall-beams

When steel plate-masonry composite structure used in the existing masonry structure with load bearing walls is removed for a large space, composite action should be considered between the beam and the supported masonry wall due to the arch effect formed in the supported wall. In order to investigate the working mechanism, failure mode, and load-carrying capacity, strain distribution in critical sections and mid-span defcection of this type of composite wall-beam, five steel plate-masonry wall-beams were tested under concentrated loads and analyzed, which considered variables of height-span-ratio of supported masonry wall, height-span-ratio of composite beam and thickness of steel plate. The results show that steel plate-masonry composite wall-beam starts failure from the masonry located at the line between loading point and supporting point; strain distribution of steel plate along section height meets the plane section assumption; the height-span-ratio of supported wall can directly influence the failure mode of masonry wall, buckling load corresponding to steel plate experiencing local buckling and ultimate load of tested specimens; the reasonable height of supported masonry wall is beneficial to the formation of composite action between supported masonry wall and composite beam, and the excessive high masonry wall will reduce the ultimate load of the tested specimen. Finally, the reasonable range for height-span-ratio of supported masonry wall was presented, and the proposed value representing the flexural stiffness of the steel plate-composite beam relative to the in-plane stiffness of the supported masonry wall was at least more than 79.     

新泰市马铃薯晚疫病田间药效筛选试验

_SSSSSS 【 】 选用了70%丙森锌可湿性粉剂、80%代森锰锌可湿性粉剂等6种药剂开展马铃薯晚疫病田间防效试验。结果表明,80%代森锰锌可湿性粉剂1500g/hm^₂对马铃薯晚疫病的防治效果最好,防效为77.4%;70%丙森锌可湿性粉剂375g/hm^₂对马铃薯晚疫病的防效次之,防效为73.6%。