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应用硫氟磺酰胺毒饵防治红火蚁 总被引:9,自引:0,他引:9
应用硫氟磺酰胺毒饵在广西陆川防治25hm^2红火蚁的结果表明,施药后3d蚁巢内即有红火蚁个体死亡。施药后7、14、21d的防治效果分别可达81.5%,93.9%和100%;施药后余下的顽固蚁巢和7d后出现的新蚁巢经再度施药后14d全部死亡;从5月23日到11月25日蚁群全部死亡的5欢监测、调查,既诱捕不到工蚁,也没有发现新蚁巢。因此,硫氟磺酰胺毒饵不仅具有高效、快速、安全、使用方便等特点,而且硫氟磺酰胺的应用完全可以取代目前国外普遍使用的二步施药法中的灌巢法。 相似文献
104.
XIONG Xiaoyan QIN Zhenbin MO Hongfang HE Dongxian YU Lintian XU Jiarong 《中国畜牧兽医》2007,47(12):4032-4040
This study was designed to evaluate the synergistic effect of VA5 immunopotentiator on pigeon ND4416 inactivated vaccine.160 healthy pigeons were randomly divided into four groups,including ND4416 strain inactivated vaccine group (NDV group),ND4416 strain inactivated vaccine and immunopotentiator (VA5) mixed group (NDV+VA5 group),La Sota inactivated vaccine group (La Sota group) and normal saline as the control group (C group),to assess their vaccine efficacy against virulent pigeon NDV by serological analysis and animal testing.Pigeons sera were collected at different time points after immunization and measured the HI antibody titer of each group.The results showed that VA5 immunopotentiator significantly improved the serum antibody level of pigeons immunized with pigeon Newcastle disease inactivated vaccine (P<0.05).In addition,comparative test of spleen lymphocyte transformation was conducted at various time points after immunization.The results indicated that VA5 effectively stimulated the lymphocyte transformation of immune pigeon.Pigeons in each groups were challenged with ND4416 strain at the 30th,90th and 180th d after immunization.The results presented that the NDV+VA5 group had 100% protection rate and higher than La Sota group.The duration of immunization test showed that the antibody titer of NDV+VA5 group reached peak 11.20log2 at the 21st d,remained 7.50log2 at 180th d,and the protection rate remained 100% at 180th d.It indicated that VA5 immunopotentiator sustained the immune duration of pigeon NDV vaccine up to 180 d.Moreover,the in vitro detoxification test results suggested that VA5 immunopotentiator reduced the in vitro detoxification cycle of pigeons after challenge.Overall,this study suggested VA5 immunopotentiator could significantly improve the immune efficacy of pigeon Newcastle disease inactivated vaccine,which provided a basis for further enhancing the efficacy of Newcastle disease vaccine,as well increased experimental data for the application of immunopotentiators. 相似文献
105.
将H5亚型禽流感病毒血凝素HA基因克隆入插入载体pllS中获得重组转移质粒p11SH5A,通过酶切鉴定获得了预期的转移质粒p11SHSA,将质粒p11SHSA和野生禽痘病毒(wtFPV)共转染鸡胚成纤维细胞(CEF),通过蓝白斑筛选纯化得到重组病毒rFPV-11SH5A.以间接免疫荧光法证实,HA基因得到了表达.将该重组病毒rFPV-11SH5A以10(5)PFU/只免疫7日龄SPF鸡,于7、10、14、18、21d分别采血分离血清检测HI抗体,于免疫21d后用10(5)ELD50的野生病毒进行肌肉注射观察疫苗保护率.结果表明,该疫苗能提供100%的保护. 相似文献
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WAHYU WIBAWA ROSLI MOHAMAD DZOLKHIFLI OMAR ABDUL SHUKOR JURAIMI 《Weed Biology and Management》2007,7(4):242-247
In 2002, the Malaysian government had banned the use of the hazardous herbicide, paraquat. Most growers perceive that paraquat is the most effective herbicide and provides the fastest mode of action to control weeds. An experiment was conducted at MAB Agriculture-Horticulture, Sepang, Selangor, Malaysia, from February 2004 to February 2005 to evaluate the efficacy and ability of the less hazardous herbicides, glufosinate ammonium and glyphosate, as an alternative to the hazardous herbicide, paraquat, in controlling weeds in immature oil palm (<3 years old). The results showed that paraquat needed high rates, 600 and 800 g ha−1 , to control weeds effectively. However, lower rates of glufosinate ammonium (200 g ha−1 ) and glyphosate (400 g ha−1 ) gave excellent weed control. The results showed that the efficacy of glufosinate ammonium and glyphosate were much better than paraquat. The results also showed that, with no direct contact with the plants, paraquat, glufosinate ammonium, and glyphosate had no adverse effect on the vegetative and generative growth of oil palm in this study. These results proved that the less hazardous herbicides, glufosinate ammonium and glyphosate, could be used as an alternative to paraquat to control weeds in immature oil palm. 相似文献
108.
Depletion of the protective ozone layer in the atmosphere leads to increasing UV‐B radiation on the earth's surface with potential effects on the response of plants to different stresses. Abutilon theophrasti, Amaranthus retroflexus, Digitaria sanguinalis and Chloris virgata are common weeds encountered in most arable fields in China. The effectiveness of herbicides used in controlling these weeds needs to be evaluated with increased UV‐B radiation. Seedlings of these four weeds were therefore grown under ambient and elevated UV‐B radiation to compare the efficacy of paraquat, a commonly used contact herbicide. Irrespective of species sensitivity to radiation, the elevated UV‐B radiation decreased the effectiveness of paraquat. Net photosynthesis rate was adversely affected except for D. sanguinalis, while the chlorophyll content was significantly reduced in A. retroflexus and C. virgata. UV‐B treatment increased the leaf surface wax and decreased the absorption of 14C‐paraquat in A. theophrasti, D. sanguinalis and C. virgata. These results suggest that the response of weeds to paraquat or the use of the herbicide may be affected by increased UV‐B radiation, to the extent that larger doses may be required to achieve desired effects. This may have damaging consequences for the environment. 相似文献
109.
烟草内生短短芽孢杆菌的分离鉴定及对烟草青枯病的防效 总被引:5,自引:0,他引:5
在烟草青枯病区采取健康烟草植株,从其茎杆内分离到2株对烟草青枯拉尔氏菌(Ralstonia solanacarum)有强拮抗作用的内生菌株009和011。形态观察、生理生化鉴定及16S rDNA序列比对结果表明,菌株009和011均归属为Brevi-bacillus brevis,009、011菌株与B. brevis(AY591911)相似性分别为99.5%和99.0%,GenBank登录号分别为DQ444284、DQ444285。生长特性研究结果表明,它们的最适生长pH值分别为6.5、7.5,最适生长温度分别为25、30℃。温室内用淋根法分别先接种009和011菌株,后接种病原菌,其防效分别为87.25%和52.30%。用009和011菌液分别和烟草青枯病菌的混合液淋根,其防效明显低于前者。田间小区试验结果表明,011菌株的防效明显高于009菌株和农用链霉素。 相似文献
110.