3种抗凝血类杀鼠剂在喀什农区防治害鼠效果及对家禽的安全性评价

为确定适于防治南疆农区鼠害的抗凝血类杀鼠剂, 在喀什地区疏勒县采用夹捕法、食饵法、粉迹法评估了杀鼠醚、溴敌隆、溴鼠灵的防治效果, 并采用灌胃法给药测试3种杀鼠剂对家鸡Gallus domestiaus和鸽子Columba livia的安全性。结果表明, 连续投放毒饵10 d后, 与溴敌隆防治区相比, 杀鼠醚防治区的阳性粉块和无毒小麦取食量的下降幅度均无显著差异, 但无毒小麦取食量下降的农户比例更高;且防治后褐家鼠比例更低, 防治期间毒饵消耗量更高。连续单独投放溴敌隆30 d的灭鼠效果可达90.9%, 但10 d溴敌隆与20 d溴鼠灵联合防治防效仅为65.9%。灌胃法测试表明, 对当地家禽类的毒性从低到高依次为杀鼠醚、溴敌隆和溴鼠灵。因此, 建议优选毒性较低的杀鼠醚或溴敌隆用于南疆农区鼠害防治。     

Bromadiolone,a New Anticoagulant Rodenticide1

A search for more effective anticoagulant rodenticides has brought about the development of a new compound, coded LM-637, and temporarily named bromadiolone. Results of efficacy tests on 10 rodent species are discussed in detail. The compound was found to be a very potent and highly palatable anticoagulant which is capable of achieving 100% mortality in Norway rats, Rattus norvegicus (Berkenhout), with 1-day feeding. Efficacy was demonstrated on all 3 commensal rodents and several important agricultural rodent pests native to the United States. A relatively few feedings (1 to 5 days) of bait containing 0.005 % bromadiolone produced death in most species tested. These rodenticidal properties make bromadiolone a most promising control agent.     

Laboratory and field trials of the rodenticide brodifacoum against warfarin-resistant Norway rats

Norway rats (Rattus norvegicus) trapped in a low-income housing area in Raleigh, North Carolina, and on a poultry farm in Garner, North Carolina, manifested high levels of resistance to warfarin in laboratory tests. Of the rats tested, 59.1 and 91.7% from the Raleigh and Garner trap sites, respectively, survived a 6-day no-choice test of a diet containing 0.005 % warfarin. The warfarin-resistant rats were subsequently given a choice of a 0.005% brodifacoum bait and a placebo diet. Of 27 rats, 19 died after a 3-day test. Survivors had consumed significantly less brodifacoum (0.1 < P > 0.05) than those that died, but the survivors also died when subjected to an additional 1-day no-choice test of the brodifacoum bait. Field trials, in which warfarin-resistant rats in four poultry houses were fed with poison bait for 14–16 days with 0.005% brodifacoum in a pelletised bait (‘Talon’), resulted in 87–99 % control being achieved.     

Brodifacoum is effective against Norway rats (Rattus norvegicus) in a tyrosine139cysteine focus of anticoagulant resistance in Westphalia,Germany

BACKGROUND: The tyrosine to cysteine amino acid substitution at location 139 of the vkorc1 protein (i.e. tyrosine139cysteine or Y139C) is the most widespread anticoagulant resistance mutation in Norway rats (Rattus norvegicus Berk.) in Europe. Field trials were conducted to determine the incidence of the Y139C mutation at two rat‐infested farms in Westphalia, Germany, and to estimate the practical efficacy against them of applications, using a pulsed baiting treatment regime, of a proprietary bait (Klerat^?) containing 0.005% brodifacoum. RESULTS: DNA analysis for the Y139C mutation showed that resistant rats were prevalent at the two farms, with an incidence of 80.0 and 78.6% respectively. Applications of brodifacoum bait achieved results of 99.2 and 100.0% control at the two farms, when measured by census baiting, although the treatment was somewhat prolonged at one site, possibly owing to the abundance of attractive alternative food. CONCLUSION: The study showed that 0.005% brodifacoum bait is fully effective against Norway rats possessing the Y139C mutation at the Münsterland focus and is likely to be so elsewhere in Europe where this mutation is found. The pulsed baiting regime reduced to relatively low levels the quantity of bait required to control these two substantial resistant Norway rat infestations. Previous studies had shown much larger quantities of bromadiolone and difenacoum baits used in largely ineffective treatments against Y139C resistant rats in the Münsterland. These results should be considered when making decisions about the use of anticoagulants against resistant Norway rats and their potential environmental impacts. Copyright © 2012 Society of Chemical Industry     

Yield reduction in wheat by simulated rat damage

Abstract

A study of simulated rat damage was done to determine the loss of wheat yield when O (control). 10, 30 and 50% ot the wheat stems were cut at tillering, booting, dough and mature crop stages. The yields at harvest from each of 128 1‐m² plots were compared by analysis of variance and least significant difference tests. Yield at the tillering stages was not significantly different from the controls but yields at all other stages differed significantly. Yield losses in tillering and booting stages were not significant for the different damage levels except for 50% stem cutting at the booting stage. The yields from dough and mature crop stages at all damage levels were significantly lower than yields from controls. No significant differences in yield at all growth stages were observed between control plots and those receiving 10% damage, but 30 and 50% damage gave significant losses.     

Weeds

Abstract

The effects of simulated rat damage (stem cutting) on IR-8 rice yield was examined. Fields were subjected to four damage levels: 0 (control), 10, 25 and 50% of the stems cut. A modified split-plot sampling design was used with ten 1 m² plots tested at each damage level in three growth stages: tillering, booting and maturity. Each of the 120 plots (2,400 hills) was harvested and yields compared by Analysis of Variance and Least Significant Difference (LSD) tests. Ten perpent of all stems removed during the tillering stage produced growth compensation and a higher yield resulted. Trends in rice yields for different damage levels showed that the later damage occurred, the greater the yield loss. An LSD analysis of yields for the damage levels revealed no significant differences during tillering. At booting, significant differences (P < 0.05) in yields were noted with > 10% of the stems cut. At maturity, yields for all damaged levels differed significantly (P < 0.01). The results of this study demonstrated that rat damage in rice up to the booting stage did not affect yield significantly. From an economic standpoint, rodent control by field baiting before booting stage is not recommended in monsoon rice.     

高置式大容量毒饵站对东北农田害鼠的防治效果初探

毒饵站是化学防鼠常用设施,可以减少非靶标动物的误食风险。目前常用毒饵站容量小、毒饵易浪费、添加毒饵不便的缺点限制了其在东北地区的大规模应用。本研究针对东北农业环境特点,设计了一种新型高置式大容量毒饵站,在黑龙江了进行为期1年的防效试验,并测试其作用范围。结果表明,这种毒饵站每年毒饵用量2.8~3.8kg,鼠密度控制率可长期保持在75%以下;其有效覆盖面积为1.1hm2,最佳防治效果的覆盖面积为0.5hm2。这些结果说明这种大容量高置式毒饵站具有毒饵添加便捷、无浪费的优点,在东北地区防治经济效益远远大于其他传统小容量毒饵站,值得在当地应用和推广。     

Crop damage and yield loss caused by two species of rodents in irrigated fields in northern Nigeria

We investigated the damage and yield loss caused by two rodent species, Arvicanthis niloticus and Mastomys (Praomys) natalensis, in cereal crops in fields near Kano, northern Nigeria from August, 1990 to April, 1992. Using the random cluster technique, we selected 100 clusters of 30 hills in each rice and wheat field, and assessed damage fortnightly, using the Cut Tiller Count method. In premature crops, damage increased from tillering stages to the dough stages. Differences in the percentages of damage (yield loss) in mature rice (4.8% in 1990 and 12.6% in 1991) and in wheat (30.0% in 1991 and 21.7% in 1992) were statistically significant between years. Severe yield losses in wheat, compared to low and moderate levels in rice (grown for the most part during the rains), were probably a result of greater consumption of the wheat, grown entirely by irrigation during the dry season when other rodent food sources were less abundant. Results of ANOVA showed significant effects of developmental stage of the crop, year of cultivation, and their interactions on the magnitude of crop damage.     

The susceptibility of the Indian field mouse,Mus booduga gray,to anticoagulant rodenticidal baits

The baseline susceptibility of the Indian field mouse, Mus booduga was established for warfarin, bromadiolone and brodifacoum by means of nochoice feeding tests. The mice were found to be more susceptible to the second generation anticoagulants bromadiolone (0.005 g kg^?1) and brodifacoum (0.002 g kg^?1) than warfarin (0-25 g kg^?1). They required 8–10 days feeding on warfarin (0.25 g kg^?1) diet for complete mortality. A feeding period of 8 days corresponding to 99% mortality was suggested as a checking test for registering future warfarin resistance in suspect samples of M. booduga.     

Bromadiolone susceptibility in wild and laboratory Mus musculus L.(house mice) in Buenos Aires,Argentina

BACKGROUND: Rodents are major pests in many agricultural systems, where they can cause significant economic losses and involve a sanitary risk. The application of anticoagulant rodenticides for rodent control has showed a decrease in effectiveness through time because of the development of resistant populations and the development of aversion behaviour. The goal of the present study was to test the susceptibility to bromadiolone and the existence of anticoagulant resistance in Mus musculus L. (house mouse) in Argentina. We conducted a feeding test with wild animals captured in poultry farms and a laboratory strain that were fed with bromadiolone bait. RESULTS: Three animals of the field experimental group survived the 21 days study period, while for laboratory animals mortality was 100%. Control field animals which were fed without anticoagulant showed 100% survival. CONCLUSION: We found evidence of the presence of anticoagulant resistant M. musculus L. in the study area. Feeding behaviour may have contributed to increasing the time of survival, and may be a mechanism that allows metabolic clearance of the bromadiolone. Under field conditions control with anticoagulants would be less effective because animals have alternative food. Copyright © 2009 Society of Chemical Industry     

Pesticides

Abstract

The anticoagulant chlorophacinone was evaluated in the laboratory for the control of the gerbils Tatera indica Hardwicke and Meriones hurrianae (Jerdon), which are major pests of agricultural crops, grassland and reforestation projects in the arid zone of India. Millet and sorghum grain treated with chlorophacinone was offered in no‐choice feeding tests. The results showed that 100% mortality occurred after seven and five days with 0.0075% chlorophacinone and after three and four days with 0.01% chlorophacinone in T. indica and M. hurrianae respectively. The anticoagulant‐treated bait was significantly less palatable than untreated bait, except bait containing 0.0075% chlorophacinone to T. indica. It is concluded that 0.0075% chlorophacinone can be effectively used to control the gerbils, especially bait‐shy populations previously exposed to zinc phosphide bait. Chlorophacinone appears to give more effective control than warfarin and fumarin, and slightly less effective control than brodifacoum.     

Influence of weather factors on sorghum earhead bug Calocoris angustatus Lethierry incidence

Abstract

Weather parameters during the same week and one, two, three or four weeks before were correlated with the population of earhead bug, Calocoris angustatus on different earhead stages of two hybrids, CSH 5 and K‐Tall, in main and ratoon crops. The weather factors in the different weeks contributing to the insect population varied with the stage of earhead, the hybrid and the nature of the crop (main or ratoon). In the main crop, the insect population at pre‐flowering, milky, dough and maturity stage was influenced by weather parameters one week before, the same, two and three weeks before respectively. Morning relative humidity was important in both hybrids at all stages, with a few exceptions. In the ratoon crop, the pre‐flowering and maturity stage populations were influenced by the weather parameters of the same week. The populations at milky and maturity stage were influenced by parameters four weeks and one week before the observations respectively. The factors influencing the population on CSH 5 and K‐Tall varied. In most cases morning relative humidity had a positive influence.     

Effects of leaf blast on growth and production of a rice crop

Rice crops grown under irrigated conditions were inoculated withPyricularia oryzae during early growth stages to study the effect of leaf blast on yield formation. The inoculations led to severe epidemics of leaf blast around maximum tillering, characterized by the presence of typical blast lesions and an accelerated senescence of heavily infested leaf tissue. Leaf blast led to a prolonged tillering and a delay in flowering and maturity.Crop growth rate and leaf area formation declined sharply during establishment of the disease and continued to be reduced till maturity. This resulted in a marked reduction of total dry matter production and grain yield. Dry matter distribution was not affected. Leaf blast reduced spikelet number, 1000 grain weight, and the fraction filled grains. From this last observation it was concluded that the reduction in grain yield was exclusively source determined.Nitrogen uptake of the inoculated crops before flowering was reduced compared to the N uptake of the control crop, but shoot N content of the inoculated crops at flowering was higher. Uptake of nitrogen after flowering was negligible in both healthy and inoculated crops. Redistribution from vegetative tissue was therefore the main source of N for grain growth. The higher N content of the shoot organs in the inoculated crops during ripening led to the conclusion that the reduced N uptake was not responsible for the yield reduction observed. Consequently, the reduction in grain yield was solely determined by a reduced carbohydrate supply.     

Efficacy and attractiveness of zinc phosphide bait in common voles (Microtus arvalis)

BACKGROUND: Minimising the concentration of active ingredient in rodenticide bait is desirable economically and for the protection of the agroecosystem. This study aimed to identify a zinc phosphide concentration that balances palatability and efficacy for common vole (Microtus arvalis Pall.) management and to compare the attractiveness of two bait carriers. RESULTS: Bait uptake of voles was reduced by 87–98% compared with plain bait when bait contained 0.4–3.2% zinc phosphide. There was an almost 50% decrease in the uptake of zinc phosphide when the zinc phosphide concentration of bait was doubled. Red dye used in commercially available bait decreased bait consumption by 10%. Daily consumption of zinc phosphide bait on days 2 to 5 was half the consumption on the first day of exposure. In bait choice tests, wheat kernels were preferred initially, but within 12 h similar amounts of wheat‐based pellets and wheat kernels were eaten. CONCLUSIONS: According to the results from the laboratory trial, a zinc phosphide concentration of 2.1% seemed to balance uptake/efficacy best and may be most appropriate for the management of common vole populations. This concentration is substantially lower than the concentration used in many registered products. A reduced concentration of active ingredient and the use of pellet bait instead of wheat which is highly attractive for birds may have advantages for agroecosystem health when applying zinc phosphide for rodent control. © Jens Jacob, Mechthild Budde and Angela Leukers, employees of the Federal Research Centre for Cultivated Plants, Germany. Printed with permission.     

Impact of the Common Vole,Microtus arvalis (Pallas) on Winter Wheat and Alfalfa Crops1)

Impact of the common vole, Microtus arvalis (Pallas), upon the winter wheat and alfalfa crops was determined. Net-bottomed coops were used for estimating the effect of vole grazing. Exposure of winter wheat to vole grazing at the stages of earing and flowering was the most harmful. Losses were up to 91% of the potential crop yield, while the proportion of the best grain size fraction (2.8 mm) dropped to a minimum level. Coefficients reflecting the influence of vole grazing on the crop were determined. The coefficient TOTAL is an index of the total impact of consumption. The impact, I_t, at time t equals the consumption, Ct, at this time multiplied by the value of TOTAL. For alfalfa, these coefficients range from 1.28 to 11.73. The results obtained in this study have made it possible to determine the effective rodent pressure on crop yield.     

枯草芽孢杆菌B1514可湿性粉剂对小麦纹枯病的防效及对土壤微生物区系和小麦产量的影响

为明确枯草芽孢杆菌B1514可湿性粉剂（WP）在小麦纹枯病防治中的应用前景,于2014-2015年在中国河北省文安县、献县、枣强县及辛集市4个实验站进行了田间试验,研究了B1514 WP对小麦纹枯病的防效,采用失重法测定了其对玉米秸秆腐解效果的影响,利用稀释平板法研究了其对土壤微生物区系的影响,并测定了该菌剂对小麦生长及产量的影响。结果表明:越冬期至拔节期,B1514 WP对小麦纹枯病的防效均显著高于B1514片剂,但明显低于戊唑醇湿拌种剂（WS）;成熟期,辛集、献县和枣强试验点B1514 WP处理组平均防效为64.0%,与戊唑醇WS处理差异不显著,比B1514片剂处理组高7.2%,差异达显著水平,而文安试验点B1514 WP处理组防效为65.2%,与B1514片剂差异不显著,但显著低于戊唑醇WS处理组。在成熟期,B1514 WP对玉米秸秆的累积腐解率为64.2%,较空白对照提高38.6%,但与B1514片剂和秸秆腐解剂处理差异不显著。此外,B1514 WP处理显著提高了土壤中可培养细菌数量（92.8%）,降低了真菌数量（48.4%）,但对放线菌数量无显著影响。采用B1514 WP拌种后,小麦株高和分蘖数分别比空白对照提高8%和12%;4个试验点小麦平均产量为7 545 kg/hm2,分别比B1514片剂、戊唑醇WS、秸秆腐解剂处理和空白对照提高6.8%、5.5%、9.3%和10.9%。研究表明,B1514 WP对小麦纹枯病具有很好的防效,并能加速秸秆腐解,增加土壤中细菌数量、降低真菌数量,促进小麦生长并增产。     

主要栽培因子对小麦纹枯病的定量效应

研究了播期、密度和氮肥对小麦纹枯病的定量效应，组建了小麦扬花期病情指数（DI1）和黄熟期病情指数（DI2）的回归模型，并对其进行了检验和解析。结果表明：两回归模型均在0．01水平上显著，且拟合较好；各个因子对纹枯病病指的影响为：播期＞氮肥＞密度；其中播期中DI1、DI2的效应均极显著；播期与密度互作（X1X2）对DI2的效应达到0．2显著水平；晚播稀植有利于控制该病的危害。最后对回归模型进行了仿真优化，提出了控制该病发生程度的优化栽培方案。     

南方灭鼠应用稻谷与大米毒饵的比较

生物测定法测得谷壳对复方88-1灭鼠剂的阻滞率为54．3％，光谱分析法测得其对敌鼠钠盐的阻滞率在47．43％—57．00％之间。相同条件下，褐家鼠Rattus norvegicus取食敌鼠钠盐稻谷毒饵量为大米毒饵的2倍多。在南方潮湿的环境下，大米毒饵更易松散、霉变，使其适口性更低。综合考虑认为南方灭鼠使用稻谷毒饵更为合适。     

旱地小麦产量及其构成因素灌溉效应的模拟分析

为揭示灌水时期与灌水量对黄土丘陵区小麦产量及其构成因素的影响规律，依据黄土丘陵典型区域定西1971-2016年气象数据及定西市安定区凤翔镇安家沟村2016年大田试验数据，利用APSIM（Agricultural Production Systems Simulator）平台，动态模拟各灌溉处理下的小麦生长发育过程，并对各灌溉响应进行模拟分析。结果表明：小麦全生育期需水量为315.25 mm，各生育阶段需水量为播种~出苗21.13 mm、出苗~分蘖26.60 mm、分蘖~拔节33.27 mm、拔节~孕穗77.17 mm、孕穗~开花69.31 mm、开花~灌浆36.19 mm、灌浆~成熟51.58 mm。为提高产量，最佳灌水时期应在播种至拔节，灌水量不宜超过60 mm；开花前各生育阶段灌溉处理都明显提高了单位面积籽粒数量，其中以分蘖~拔节阶段（TS）最明显，拔节~孕穗阶段（JS）灌水量不宜超过80 mm、孕穗~开花阶段（BS）灌水量不宜超过20 mm。开花~灌浆阶段（FS）灌水量40 mm对粒重增加的促进作用最明显。     

Reducing sodium fluoroacetate and fluoroacetamide concentrations in field rodent baits

Laboratory trials were carried out in order to establish the minimum active ingredient (a.i.) concentration of sodium fluoroacetate (1080) and of fluoroacetamide (1081) in wheat baits employed againstMicrotus guentheri, the Levant vole, andMeriones tristrami, Tristram’s jird, without interfering with the toxicants’ efficacy. Using a mixture of treated and untreated grain enabled a greater reduction in the a.i. concentration compared with that which could be achieved whenall the grains offered contained a lower a.i. concentration of the toxicants. ForM. tristrami the lowest efficient final a.i. concentration in the bait was 0.0125% for 1080 mixed bait (1:4 mixture of 0.05% poison grains with filler grains) and 0.01% for 1081 mixed bait (1:10 mixture of 0.1% poison grains with filler grains); and forM. guentheri — 0.005% mixed bait of 1080 or 1081 (1:10 mixture of 0.05% poison grains with filler grains). This leads to a reduction of the hazards involved in the use of prepared baits of these toxicants in the field.