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楸螟生物学特性及防治研究 总被引：1，自引：0，他引：1
楸螟在河南一年发生两代,以老熟幼虫在枝、干中越冬。第二代成虫羽化盛期及第一代幼虫孵化盛期(5月),是进行药剂防治的最佳时期。在此期间喷洒20％杀灭菊酯乳油1万倍液3次或2.5％溴氰菊酯乳油5000倍液4次(间隔5—10天),防治效果达100％;根埋3％呋喃丹颗粒剂防治1—2年生幼林,每株用量25g,防治效果为97.87—98.1％。 相似文献
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桉树尺蠖是闽南地区桉树林中发生最严重的食叶害虫,为控制其危害,确定最佳防治适期,通过采用林间喷洒2%阿维菌素+苏云金杆菌粉剂的方法,比较第1代幼虫危害早期(5月2日)、危害中期(5月13日)和危害后期(5月30日)分别进行防治的效果,结果表明:在第1代尺蠖幼虫危害早期,每667 m2使用500 g药剂进行防治,5 d后虫口减退率为97.5%;危害中期每667 m2施用500 g药剂进行防治,5 d后虫口减退率为95.3%;危害后期每667 m2施用1000 g药剂进行防治,5 d后虫口减退率为83.9%,明显比早期和中期开展防治的低。危害早期和中期施药防治,第2代幼虫不产生危害;而危害后期开展防治,第2代幼虫仍有轻度危害。在危害中期以前防治对提高防治效果、减少损失有显著作用,同时还能减少农药的使用量。 相似文献
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美国白蛾无公害防治 总被引：2，自引：0，他引：2
辽宁省自1979年发生美国白蛾以来就开展了生物(仿生物)药剂防治美国白蛾试验,经过十几年的试验、推广、应用确,定了几种药剂的防治方法。1美国白蛾核型多角体病毒1 1防治方法将美国白蛾2～3龄幼虫喂食喷过美国白蛾核型多角体病毒的树叶进行接毒,接毒后5～7d收取虫尸,盛在暗色瓶内放在冰箱(-4℃)或冻库内(-10℃)保存,或制成粗提纯剂放在冰箱或冷库内保存。第一代防治用头年第二代虫尸提纯剂,5×10PIB mL,第二代防治用当年第一代虫尸稀释液,2×10PIB mL。1 2防治效果从防治效果看出(见表1),2～3龄幼虫的死亡高峰为第8天至第9天,3龄为第1… 相似文献
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为了研究钾对缓解樟子松苗木淹水胁迫的生理效应.该试验在盆栽条件下,以2a生樟子松为试材,设置0(CK)、4、8、12g/株 4个钾肥施用量处理,3次重复.试验结果显示:(1)随淹水时间延长,樟子松光合速率降低,施用钾肥提高了光合速率,第7～10天,8g/株和12g/株处理显著高于4g/株;(2)施钾提高了第4～10天的... 相似文献
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油橄榄叶部病害的发病高峰期在4～6月份。试验用春雷霉素、嘧啶核苷类抗菌素、异菌脲、多粘类芽孢杆菌4种生物制剂相应浓度梯度的药液对其进行防治。结果表明：单次施药10 d后多粘类芽孢杆菌2 000～3 000倍液防治效果达到67.21%,异菌脲1 500倍液防治效果为59.02%,防治效果均超过50%,可作为速效药剂施用;2次施药10 d后异菌脲1 000倍液、多粘类芽孢杆菌2 000倍液防治效果达到71.95%,说明这2种生物制剂可以多次施用达到长期防治目的。 相似文献
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几种药剂对银杏大蚕蛾的毒力测定和防效对比试验 总被引：1，自引：0，他引：1
对几种药剂防治银杏大蚕蛾Dictyoploca japonica Butler 2龄幼虫进行了室内毒力测定、林间小区防治试验.室内毒力测定结果表明1.2％烟碱·苦参碱乳油对银杏大蚕蛾2龄幼虫毒力最强,其次为1.8％阿维菌素乳油,最弱的为4.5％高效氯氰菊酯.林间小区防效试验的3种药剂对银杏大蚕蛾2龄幼虫均有很好的防治效果,1.2％烟碱·苦参碱112.5 g/hm2,20％杀铃脲56 g/hm2,25％灭幼脲150 g/hm2为最佳剂量,防效为90.7％ ～92.1％.1.2％烟碱·苦参碱乳油杀虫速率高峰期在第1天;2种仿生物制剂击倒速率较慢,高峰期出现在第10天.1.2％烟碱·苦参碱防治费用最低. 相似文献
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美国白蛾NPV大面积应用试验 总被引：1，自引：0，他引：1
1983年至1985年连续三年利用美国白蛾核型多角体病毒进行了2311公顷的大面积试验,防治效果平均为91.9％。防治第一代美国白蛾使用头年第二代美国白蛾发生期生产的感病致死虫尸,其制剂浓度为2—3×10~7PIB/ml;防治第二代美国白蛾使用当年第一代生产的感病致死虫尸,其制剂浓度为1.5-2.0×10~7PIB/ml,防治效果均在90％以上;如使用粗提纯液防治,其制剂浓度为1.3×10~7PIB/ml,防治效果在95％以上。防治龄期为2—3龄。用感病致死虫尸稀释液防治美国白蛾其死亡高峰为13一15天,死亡结束时间为18—19天。 相似文献
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印楝提取物对桑天牛产卵量及卵孵化率的影响 总被引：19，自引：3，他引：19
使用一定浓度的印楝提取物 (NeemEC)处理的构树枝条作为天牛的食物 ,研究了其对桑天牛产卵量及卵孵化率的影响。在室温下 ,将成对的天牛放在盖有铁砂网的直径 2 5cm高的塑料桶中进行实验。用含印楝素 50× 1 0 -6g/mL的印楝提取物处理枝条 ,处理组天牛 ( 7对 )在 1 5d试验中 ,其每天对平均产卵量为2 0 0± 1 56个 ,而对照组每天平均产卵量为 1 0 33± 3 33个。经T—检验处理组与对照组之间差异显著。用含印楝素 1 0 0× 1 0 -6g/mL的印楝提取物处理枝条 ,在 1 5d试验中 ,处理组 7对天牛从第 5d开始死亡 ,至第 8d全部死亡 ,按实际成活天数计算 ,其每天每对平均产卵量为 1 0 0± 1 4 1个 ,而对照每天每对平均产卵量为 1 3 73± 2 90个。经T—检验两者之间差异显著。取食含印楝素 50× 1 0 -6g/mL的印楝提取物处理枝条后天牛产的卵需经 1 9d达到其最终孵化率 ,33 33% ;而对照组 9d达到最终孵化率 98 96%。在进行了 2 4d的选择取食试验中含印楝素 1 0 0× 1 0 -6g/mL的印楝提取物处理枝条 ,1 0对对照组天牛每天每对平均取食量为 3 53± 0 38g,而处理组天牛每天每对平均取食量 3 4 2± 0 60 g。经T—检验两者差异不显著。这说明桑天牛不能分辩含印楝提取物的食物 ,即印楝提取物对桑天牛不具拒食性。 相似文献
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应用盆栽试验方法,比较研究了水松幼苗在不同水分和铜胁迫条件下的生长表现。结果表明:①在渍水(Wa)、隔天渍水(Wb)及3天浇水1次(Wc)和7天浇水1次(Wd)等4种水分胁迫条件下,Wc处理组幼苗生长表现最好;Wa和Wb处理组次之,Wd处理组幼苗在第7 d就出现萎焉,至第10天时全部死亡。②在Cu2+50(Cu50)、100(Cu100)、200(Cu200)、500mg·L-1(Cu500)等4种铜胁迫条件下,水松裸根苗在第10天时全部死亡;水松土培苗也出现不同程度的死亡和生长受抑现象,随着铜胁迫时间的延长,其成活率和生长量与对照组(Cu0)的差异增大;至90 d时,Cu500处理组的苗木存活率只有22.2%,其幼苗高增长量仅为对照组的38.2%。 相似文献
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Chlamydospores of four isolates of Phytophthora cinnamomi were produced on mycelium grown on medium with or without 100 μg phosphite/ml, then tested for germination on medium containing no phosphite or 100 or 160 μg phosphite/ml. For each isolate when spores were produced on medium without phosphite, there was no effect of phosphite on germination. However, chlamydospores produced in the presence of 100 μg phosphite/ml showed significantly lower germination on media with no phosphite, 100 or 160 μg phosphite/ml than those produced in the absence of phosphite. For isolates known to be phosphite sensitive, the level of viable non‐germinated chlamydospores was higher amongst those produced on medium containing phosphite than amongst the controls, suggesting phosphite induces chlamydospore dormancy in some isolates of P. cinnamomi. Chlamydospores were produced uniformly across the radius of colonies on solid or liquid control media, but on media containing 100 μg phosphite/ml, chlamydospore production was lower in the centre of the colony and peaked at a point where mycelial morphology changed from tightly packed to sparse. This change in mycelial morphology and the peak in chlamydospore numbers did not occur when the pathogen was grown on liquid medium renewed every few days. In renewed medium, chlamydospores were evenly distributed across the radius of the colony. 相似文献
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对蓝莓的组培快繁技术进行了研究。结果表明:茎段在1/3MS+BA1.5mg/L+NAA0.2mg/L+ZT1.5mg/L培养基上继代一次即可出苗,繁苗系数8倍以上;生根培养以1/4MS+IBA0.5mg/L培养基为最好,生根率达100%,并且每株可达5～10条根;移栽基质以腐苔藓为最好,成活率达80%以上。 相似文献
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Göransson A 《Tree physiology》1999,19(2):111-116
Small birch plants (Betula pendula Roth) were cultivated in a hydroponic spray solution where the relative growth rate (R(G); day(-1)) was controlled by the relative supply rate of zinc (R(Zn); day(-1)). After an adjustment phase to steady-state growth, R(G) equaled R(Zn). The R(Zn) treatments were 0.05, 0.125 and 0.20 day(-1) with free access to all other nutrients. In an additional treatment, there was free access to all nutrients, including zinc (FA treatment). The pH of the nutrient solution was approximately 4.5 and conductivity was 100 &mgr;S cm(-1). The duration of each treatment depended on R(Zn) and ranged from 4 (FA treatment) to 10 weeks (at R(Zn) = 0.05 day(-1)). The plants showed persistent and typical zinc-deficiency symptoms at steady-state growth when R(G) was 0.05 and 0.125 day(-1), whereas there were few symptoms when R(G) was 0.2 day(-1). The Zn concentration of the plants ranged from 8 (at R(Zn) = 0.05 day(-1)) to 21 &mgr;g g(DM) (-1) (DM = dry mass) (at R(Zn) = 0.2 day(-1)) and was approximately 42 &mgr;g g(DM) (-1) in the FA treatment. Uptake rates of Zn, calculated per root growth rate (&mgr;mol g(DM, root) (-1)), were about 2.8 times higher at R(Zn) = 0.20 day(-1) than at R(Zn)= 0.05 day(-1). The root and stem biomass fractions were approximately constant at all supply rates of Zn, whereas the leaf biomass fraction tended to increase with increasing supply rate of Zn. Net assimilation rate was constant from FA to an R(Zn) of 0.125 day(-1) but decreased by a factor of about 2 at R(Zn) = 0.05 day(-1). Leaf area ratio and specific leaf area were smaller at low supply rates of zinc than at high supply rates. 相似文献
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天牛幼虫排出的虫粪在指示天敌寻找寄主的过程中起着重要的作用。通过在光肩星天牛幼虫发生期定期收集幼虫虫粪的方法,首次研究了林间天牛幼虫排粪量的变化规律。结果显示,光肩星天牛成虫羽化前,排粪总量呈现由上升到下降的过程,单个排粪孔的日平均排粪量为(0.030 2±0.002 1)g,单排粪孔的日最大排粪量可以达到0.319 4 g。同时研究了幼虫排粪量与寄主树的胸径、树皮厚度、树皮含水量和排粪孔大小的关系,结果表明,在调查期内,无论是各个排粪孔的排粪总量还是日均最大排粪量,均与排粪孔的大小有直接关系,而与其他几个因子无关。通过在树干上缠绑胶带形成的微栖境,采集到了光肩星天牛的天敌花绒寄甲成虫,表明花绒寄甲的发生与寄主天牛的发生紧密相关。 相似文献
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To determine if bifenthrin residues elicit morbidity and surfacing behavior in wireworms, larvae of the dusky wireworm, Agriotes obscurus (Coleoptera: Elateridae) were placed in field soil treated with the pyrethroid insecticide bifenthrin ~1 year previous. Morbidity was immediate and lasted as long as wireworms remained in the soil, disappearing quickly after transfer to clean soil. In 2009, field soil treated 336 days previous with bifenthrin at 340 g AI/ha elicited morbidity symptoms similar to that elicited by soil freshly amended with bifenthrin at 100 g AI, and analysis of the field soil confirmed residual levels of bifenthrin exceeding 100 g AI/ha. In 2010, wireworms placed in field soil treated 343 days previous with bifenthrin at 100, 200, and 300 g AI/ha responded as in 2009, with the degree of morbidity increasing with the rate of insecticide, and with wireworms in a non-feeding state more affected than those in a feeding state at each rate. In both 2009 and 2010, moribund wireworms moved to the soil surface within 1 day of placement in the soil containing residual bifenthrin and remained there until reburied, after which they often resurfaced. To confirm that the bifenthrin residues elicited repellency, wireworms were placed in soil window bioassays containing field soil with residual bifenthrin. Wireworms behaved markedly different upon contacting soil containing the residues than when exposed to untreated soil, both in the presence and absence of an attractant, but were less likely to avoid soil containing residual bifenthrin when attracted by wheat seedlings placed inside it. 相似文献
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Ammar Khalil Mohamed Ahmed Luping Jiang Fang Wang Song Chen Xueyan Zhou Xiaona Pei Xiyang Zhao Guanzheng Qu 《林业研究》2020,31(1):45-55
To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in height.The growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly significant.ANOVA results for tree height and basal diameter indicated that all sources of variance showed significant differences(p<0.001).The average tree height and basal diameter for all the four clones under the different treatments ranged from 155.39 to 235.04 cm,and from 13.71 to 17.42 mm,respectively.A highly positive correlation between the extreme k value and tree height was observed,suggesting that the k value was an accurate estimation of tree height.For model parameters,the earliest average time point for the onset of the rapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 cm.The highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,respectively.The most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O). 相似文献