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61.
[目的]探索甜菜夜蛾和烟青虫卵的形态学特征,为卵的发育及种群鉴定积累资料。[方法]运用扫描电子显微镜对两种昆虫卵的超微结构特征进行观察。[结果]甜菜夜蛾和烟青虫的卵均为球状,前者卵壳表面具网状纹饰,且分布有较多的呼吸空,卵孔外围的梅花状刻纹卵石状;后者卵壳表面隆起贯穿两极,隆起间具梯形纹饰,亚极区的隆起上分布有乳突,未见呼吸孔的分布。[结论]甜菜夜蛾和烟青虫卵的超微结构特征存在种间特异性,超微特征丰富了两种昆虫的个体发育资料,也为两种昆虫的卵及其外类群的准确鉴定提供参考。  相似文献   
62.
黄健  李晶  张璞  李杨 《安徽农业科学》2010,38(23):12913-12915,12922
国内棉铃虫划分为热带型、亚热带型、温带型和新疆型4个地理型,预测棉铃虫的发生对棉铃虫的防治和安排农事生产有着重大意义。笔者选取新疆麦盖提县植保站棉铃虫发生资料与同期气象资料按月平均处理后,通过相关分析法选出与发生等级相关的因子作为预测因子,分别用逐步回归法和人工神经网络建立该地的预测预报模型。结果表明,BP神经网络预报模型的拟合精度和预报精度高于逐步回归模型,在干旱区,温度对棉铃虫发生的影响强于降雨量的影响。  相似文献   
63.
棉铃虫氨肽酶N基因片段克隆、表达和内源蛋白检测   总被引:1,自引:0,他引:1  
氨肽酶N(APN)是苏云金芽孢杆菌杀虫毒素Cry在昆虫中肠中的一个重要受体。研究氨肽酶N在昆虫中肠中的分布特征对于阐明Cry毒素的杀虫机理和昆虫对Cry毒素的抗性机理具有重要的意义。通过RT-PCR的方法从棉铃虫中肠上皮细胞中克隆得到氨肽酶N的基因片段APN1551,并诱导表达纯化得到其重组蛋白APN517。以此蛋白为抗原,制备其抗血清。用该抗血清能检测到棉铃虫中肠上皮细胞中的APN蛋白。为研究Cry毒素的作用机理奠定基础。  相似文献   
64.
以40%乐果乳油和4.5%高效氯氰菊酯乳油为对照药剂,研究不同剂量的Bt悬浮液对辣椒烟青虫防治效果,结果表明,在辣椒结果盛期(7月25日),烟青虫1~2龄幼虫期,用Bt悬浮液80 mL/667m2对水50kg进行喷雾,防治效果达83.67%~87.91%,为最佳剂量。  相似文献   
65.
李胄  郑永善 《湖北农业科学》2016,(12):3084-3088
利用同在半径5 km区域内连续10年的湿度和棉铃虫(Helicoverpa armigera Hübner)百株卵量的调查资料,分析研究了湿度与棉铃虫发生的关系。结果表明,2月平均绝对湿度和最小绝对湿度均与二代棉铃虫百株卵量呈极显著正相关,11月的定时最小相对湿度与次年二代棉铃虫百株卵量呈显著负相关,11月的月平均绝对湿度和月平均相对湿度与次年二代棉铃虫百株卵量呈极显著负相关,10~12月的5种湿度资料均与次年二代棉铃虫百株卵量呈负相关。建立了5个棉铃虫百株卵量与湿度因子呈显著或极显著相关的回归方程。  相似文献   
66.
Abstract

Organochlorine, organophosphate (o.p.) and carbamate insecticides have been extensively used in Australia to combat Lucilia cuprina Wied. the main initiator of fly-strike of sheep occurring wherever sheep are run on the continent. The improved mules operation, mid-season crutching and insecticides are important in the management of Merino sheep. Insecticides are particularly valuable against body strike, especially in young sheep, in years with intermittent rain during the warmer months. Resistance to larvicides developed in the blowfly over a period of 10y from 1957. The time between the introduction of various insecticides and development of resistance is considered and a comparison made between the emergence of resistance problems to the newer synthetic insecticides in the housefly in Denmark, and in the blowfly in Australia. To provide a complete history of insecticides against the blowfly reference is made to arsenicals, to which there was no suspicion of resistance until low order cross resistance was diagnosed in o.p.-carbamate resistant strains. Some seven years after their introduction DDT and γ BHC were replaced by cyclodiene insecticides in 1954/1955. Reasons are advanced to explain the non-emergence of resistance to DDT and BHC in that period. Resistance to dieldrin and aldrin developed in late 1957 after which diazinon was introduced. The resistance has a typical BHC/dieldrin resistance spectrum and is due to a semi-dominant gene which has persisted in the field in the absence of pressure from cyclodiene insecticides. Non-specific resistance to o.p. insecticides developed in two steps. Low order resistance, diagnosed in 1965, was supplemented by an additional resistance mechanism in 1966, three alleles on two chromosomes are involved. The carbamate, butacarb, was effective against o.p. resistant strains of the blowfly when introduced in the 1966/67 season. In 1967, resistance to butacarb was diagnosed and rapidly became widespread. For the past three fly seasons larvae have been used to monitor resistance levels to o.p. and carbamate insecticides; resistance factors to both these classes of insecticide are significantly higher in larvae than adult females. Resistance levels to o.p. insecticides have stabilised. By contrast resistance levels to butacarb have doubled. A combined o p.-carbamate resistance generally applies in field samples. Larvae from o.p.-carbamate resistant strains form artificial strikes earlier than susceptible larvae, particularly on sheep treated with butacarb. It is concluded that registered o.p. insecticides, but not butacarb, will still give considerable protection against fly-strike, providing the maximum levels of o.p. resistance, reached in laboratory selection programmes, are not exceeded in the field. Investigation into o.p. resistance in the species suggests that the resistance mechanisms place their carriers at a disadvantage in the absence of selection pressure. Measures to minimise the amount of insecticide used against the blowfly are therefore strongly advocated—these include: the improved mules operation, mid season crutching and good animal husbandry.  相似文献   
67.
We determined the effects of petroleum spray oil (PSO) (Caltex Canopy®) on oviposition responses of Helicoverpa armigera Hubner and Ostrinia nubilalis Hubner adults, and larval survival of the pest moths on cotton and maize plants in the laboratory. Application of 2% (v/v) of the PSO deterred H. armigera oviposition. Increasing the rate from 2 to 5% (v/v) did not significantly reduce the number of eggs laid by H. armigera on the treated plants. In contrast, the minimum rate at which the oil could deter oviposition of O. nubilalis on maize plants was 5% (v/v). Increasing the rate from 5 to 10% (v/v) did not significantly reduce the number of eggs laid per plant. However, a reduction in the rate of the PSO from 5 to 3% (v/v) resulted in a 73.9% increase in oviposition activity on the maize plants. In wind tunnel bioassay tests, all mated H. armigera females tested could detect and settle on plants treated with water but with plants treated with PSO at various times, only 50% of tested females settled on the plants 4?–?5 days after treatment (DAT) and none on the plants 0?–?2 DAT. A solid phase micro-extraction (SPME) test to determine the effect of the PSO on volatiles released by the cotton plants showed that the quantity of volatiles released by the cotton plants treated with PSO was lower than for water treated plants. This indicates that the PSO sprays may be suppressing or masking the leaf surface volatiles of the cotton plants, thereby deterring oviposition of H. armigera. Larval survival data show that PSO sprays can cause direct mortality of first, second and third instar O. nubilalis larvae. PSOs may have the potential to be integrated into pest management programme targeting H. armigera and O. nubilalis on cotton and maize crops, respectively.  相似文献   
68.
新疆南部转基因棉区棉铃虫种群长期动态研究   总被引:2,自引:0,他引:2  
(Bacillus thuringiensis)基因抗虫棉在新疆南部推广已超过10 a,为探索Bt棉大面积种植对棉铃虫(Helicoverpa armigera)种群动态的影响,于1999-2010年使用诱虫灯监测了Bt棉大面积种植区域(麦盖提)和非Bt棉大面积种植区域(阿瓦提)棉铃虫的种群动态。结果表明:新疆南部地区20世纪90年代末发生棉铃虫害较重,2000-2004年种群数量保持较高水平;自2005年Bt棉大面积推广以后,Bt棉区棉铃虫的种群数量显著下降,棉铃虫种群数量随Bt棉种植比例的上升而下降(P<0.05);]随着Bt棉大面积推广年数的增加,Bt棉区棉铃虫各代种群数量均逐渐下降,第二代种群数量和高峰期蛾量下降速率均较越冬代和第一代快,且第二代棉铃虫种群相对丰富度也逐渐下降。因此,新疆地区Bt棉的大面积种植能较好地控制棉铃虫的种群数量,而且对第二代棉铃虫种群的控制效果最好。  相似文献   
69.
戴珏  冯再兴  王影  李凤丽 《安徽农业科学》2013,(27):11022-11023
[目的]筛选出防治烟青虫的高效、低毒杀虫剂。[方法]通过大田喷雾方法研究了5种杀虫剂对烟青虫的防治效果。[结果]5种杀虫剂对烟青虫均具有较好的防治作用。其中以8000IU/山苏云金杆菌悬浮剂1500g/hm^2、10%醚菊酯悬浮剂1350ml/hm^2、25g/L高效氯氟氰菊酯乳油375ml/hm^2喷雾处理对烟青虫的防治效果最好,药后7d防效分别达到92.94%、91.00%和90.96%,明显高于其他2种药剂及清水对照;5%高氯·甲威盐微乳剂90g/hm^2、0.5%苦参碱水剂1500g/hm^2喷雾处理对烟青虫的药后7d防效均也达到80%以上。[结论]为烟青虫防治和烟草生产提供了理论依据。  相似文献   
70.
通过超声波破碎、硫酸铵盐析等方法从10株昆虫病原线虫共生菌的发酵液中分离出各菌株的胞内和胞外蛋白,测定各蛋白样品含量及其对棉铃虫初孵幼虫的生长抑制毒性,并用Native-PAGE和SDS-PAGE对各粗蛋白组分进行初步分析。结果表明有7个菌株的胞内和胞外蛋白对棉铃虫初孵幼虫生长均显示出不同程度的抑制生长活性。其中以嗜线虫致病杆菌3个菌株CB6、All和Bw活性最强,其胞内蛋白的活性分别达97.1%、97.9%、97.2%,胞外蛋白分别达95.8%9、6.3%、88.6%。不同菌株胞内胞外蛋白产量各不相同。电泳图谱表明,不同菌株间及同一菌株胞内胞外蛋白有差异,但近缘菌株相似。  相似文献   
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