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81.
松褐天牛引诱试验初报 总被引:15,自引:0,他引:15
松材线虫病[Bursaphelenchus xylophilus(Steiner and Bubrer,1934)Nickle 1970]自1982年在我国南京中山陵发现以来,现已扩散至南京、镇江两市的12个区(县),安徽省马鞍山市、和县及滁县的部分松林。同时,在深圳马尾松林也发现了松材线虫为害(由香港疫区蔓延而来)。松褐天牛Monochamus alternatus Hope为该病的传播媒介。 相似文献
82.
1998~1999年在山西太原进行3%啶虫脒乳油防治棉蚜、麦蚜、菜蚜和苹果黄蚜田间小区药效试验。结果表明 ,啶虫脒对这几种蚜虫均有良好的防治效果。使用3%啶虫脒乳油0.6~0.9g(a.i.)/667m2 或10~20mg/kg稀释液 ,在蚜虫发生盛期喷雾防治 ,防治效果可达90%以上 ,持效期棉蚜、麦蚜、菜蚜可达10d以上 ,苹果黄蚜可达15d以上 ,与生产上推广使用的10%吡虫啉可湿性粉剂1.5g(a.i.)/667m2或25mg/kg稀释液防效相当。是一种理想的防治农作物蚜虫可供选择药剂 相似文献
83.
在田间小区试验条件下,粉锈宁喷雾防治小麦条锈病,每666.6m~28克用药量对各类型感病小麦品种的效应是有显著差异的,对慢锈品种和前期中感,但抽穗后有抗性的品种均可控制为害,而对极感品种则未能控制产量损失;等比系列用药量对各类型感病品种的效应也是有明显差异的,在 ED_(50)和 ED_(95)(克/666.6m~2)平均值上,极感品种为9.38和74.85,高感品种为4.53和25.43,中感品种为3.62和20.96,慢锈品种为1.82和15.30。根据这一结果,模拟出各类型感病品种大田防治的每666.6m~2适宜用药量,高感品种9—12克,中感品种7—9克,慢锈品种4—6克,并经实践证明,这一剂量标准是可行的。拌种对压低各类型感病品种的成株期病情也有明显差异,造成这种差异的主要原因是各类型品种流行速度不同。 相似文献
84.
樱桃致死黄化病病原研究 总被引:1,自引:0,他引:1
在电镜下,樱桃致死黄化病株筛管细胞中,观察到典型的类菌原体,大多数为球状,大小为132-321×168-520nm,无细胞壁,仅有双层细胞膜。抗菌素试验表明,四环素对本病具一定的治疗效果;而青霉素无效。初步认为此病为类菌原体引起的病害。 相似文献
85.
杂交制种稻粒黑粉病接种体芽殖附生阶段的研究 总被引:1,自引:0,他引:1
稻粒黑粉病(Neovossia horrida)是一种田土积累、种子传带、花期侵染的严重病害。其初次侵染源是病菌的冬孢子。 相似文献
86.
Hashimoto S Kimura K Iwata H Takakura R 《The Journal of reproduction and development》2003,49(1):61-66
The effects of the medium (TCM 199 or SOFaa) and temperature (20 or 39 C) during meiotic arrest by cycloheximide (CHX) under air on the developmental competence of bovine oocytes after in vitro maturation (IVM) and fertilization (IVF) were investigated. Oocytes were maintained in meiotic arrest by 10 microg/ml CHX in a 50-microl droplet of 25-mM HEPES-buffered TCM 199 (H199) at 39 C or synthetic oviduct fluid (HSOFaa) at 20 or 39 C in air for 24 h. After release from the arrest, the oocytes was matured and fertilized in vitro and their developmental competence was examined. The developmental rate of oocytes arrested in HSOFaa at 20 C to the blastocyst stage was similar to that of non-arrested oocytes but was significantly higher (P<0.05) than that of oocytes arrested at 39 C in H199 or in HSOFaa. In consideration of oocyte transport conditions, we also investigated the meiotic arrest of oocytes maintained in a 0.25-ml straw by CHX individually with 10 microl HSOFaa or as a group (40-50 oocytes) with 170-200 microl HSOFaa at 20 C in air for 24 h. After release from meiotic arrest, the developmental competence of these oocytes was assessed similarly. The developmental rate of oocytes treated with CHX individually was similar to that of those treated with CHX in 50-microl droplet of HSOFaa at 20 C. However, the developmental rate of oocytes treated with CHX as a group was lower than that of oocytes treated with CHX in a 50-microl droplet. Five blastocysts developed from oocytes maintained in meiotic arrest in a plastic straw were transferred to five recipient heifers. Consequently, three recipients became pregnant and 2 calves were delivered. The results of the present study indicate that bovine oocytes treated with CHX in HSOFaa at 20 C under air retain the same developmental competence as non-arrested oocytes. 相似文献
87.
88.
Shu Q Hillard MA Bindon BM Duan E Xu Y Bird SH Rowe JB Oddy VH Gill HS 《American journal of veterinary research》2000,61(7):839-843
OBJECTIVE: To determine efficacy of vaccines incorporating QuilA, alum, dextran combined with mineral oil, or Freund adjuvant for immunization of feedlot cattle against Streptococcus bovis and Lactobacillus spp. ANIMALS: 24 steers housed under feedlot conditions. PROCEDURE: Steers were randomly assigned to 4 experimental groups and a control group. Animals in experimental groups were inoculated on days 0 and 26 with vaccines containing Freund adjuvant (FCA), QuilA, dextran combined with mineral oil (Dex), or alum as adjuvant. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were measured, along with fecal pH, ruminal fluid pH, and number of S bovis and Lactobacillus spp in ruminal fluid. RESULTS: Throughout the study, serum anti-S bovis and anti-Lactobacillus IgG concentrations for animals in the Dex, QuilA, and alum groups were similar to or significantly higher than concentrations for animals in the FCA group. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were significantly increased on days 26 through 75 in all 4 experimental groups, and there was a linear relationship between anti-S bovis and anti-Lactobacillus IgG concentrations. For animals in the QuilA and Dex groups, mean pH of feces throughout the period of experiment were significantly higher and numbers of S bovis and Lactobacillus spp in ruminal fluid on day 47 were significantly lower than values for control cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that immunization of feedlot steers against S bovis and Lactobacillus spp with vaccines incorporating Freund adjuvant, QuilA, dextran, or alum as an adjuvant effectively induced high, long-lasting serum anti-S bovis and anti-Lactobacillus IgG concentrations. Of the adjuvants tested, dextran may be the most effective. 相似文献
89.
90.
半胱亚磺酸脱羧酶(CSD)基因在大鼠睾丸组织中的表达及其序列分析 总被引:1,自引:0,他引:1
试验根据大鼠肝脏牛磺酸生物合成关键酶——半胱亚磺酸脱羧酶(CSD)基因已知核苷酸序列,设计了1对特异的寡核苷酸引物,对提取的睾丸组织总RNA进行RT-PCR扩增,扩增出468 bp的DNA片段,在国际上首次证明CSD基因在大鼠睾丸组织中存在表达,即牛磺酸可在大鼠睾丸组织中生物合成。测定了扩增的睾丸组织CSD基因核苷酸序列,并与已知肝脏CSD基因核苷酸序列及其对应的氨基酸序列作了同源性分析。结果表明:睾丸组织CSD基因核苷酸序列同已知肝脏CSD基因核苷酸序列的同源性为99.8%,其对应氨基酸序列的同源性为100%。 相似文献