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91.
凤阳县白背飞虱发生规律及综合防治技术 总被引:1,自引:0,他引:1
根据安徽省凤阳县历年水稻白背飞虱的测报资料 ,探讨了水稻白背飞虱Sogatellafurcifera在江淮流域的发生规律。通过分析影响该地区白背飞虱发生的主要影响因子并结合当地的实际情况 ,确定其综合防治策略及方法 ,为该地区白背飞虱的综合防治提供理论依据 相似文献
92.
通过对1990—2012年云南省师宗县4—5月出现的白背飞虱灯诱高峰日进行轨迹模拟以及降虫高峰日的风场分析,得到以下结果:4月下旬,师宗上空盛行西风,白背飞虱虫源主要来自缅甸东北部,部分来自越南北部和金三角地区;5月份,西南风为盛行风向,其中上中旬的虫源地主要分布在越南西北部、老挝北部和滇西南,缅甸东北部可提供部分虫源;下旬则主要分布在滇西南,部分虫源来自越南西北部、老挝北部和缅甸东北部。对降虫高峰期的大气环流背景、峰日风温场、降雨等气象因子的分析结果表明,降水、风切变和气流垂直扰动是造成白背飞虱集中降落的主要因子。 相似文献
93.
白背飞虱雌成虫取食N22后,对马拉硫磷敏感性随取食天数增加呈增高趋势;而对叶蝉散的敏感性变化则正相反,在取食N22 1天后酯酶/羧酸酯酶即表现高水平的诱导活性,尔后随取食时间延长而降低,取食抗褐飞虱品种ASD7后,其体内酶活及对药剂抗性呈升高趋势。不同水稻品种中总酚含量以N22显著为高,相关分析表明,水稻叶鞘中的酚类物质可能是品种影响飞虱药剂敏感性的主要因素之一,因此,在生产实践中,适宜的杀虫剂与飞虱抗性品种应协同使用,以充分发挥各自的有效作用。 相似文献
94.
大气环流特征量的水稻白背飞虱发生程度预报模型的研究 总被引:8,自引:3,他引:8
根据500hPa大气环流特征量能表征天气形势和控制天气条件的这一特性,利用线性及单调曲线相关与最优化因子相关两种技术对环流特征量因子进行普查、对比分析,发现白背飞虱虫情指标与环流因子之间关系不仅是线性及几种单调曲线的关系,而且还存在非线性、非单调的单峰(谷)型的相关关系,并从中挑选一批与水稻白背飞虱虫情指标相关极其显著、稳定性强、因子间相互独立、可靠的大气环流特征量作为预报因子,在此基础上,建立了江苏省水稻白背飞虱虫情指标预报的环流模型,且还证实了模型中的环流因子与影响白背飞虱迁入、发生发展的气象条件呈显著相关关系,为预报白背飞虱发生程度提供了新的长期因子和新途径。 相似文献
95.
96.
南方水稻黑条矮缩病毒介体昆虫白背飞虱的传毒特性 总被引:2,自引:0,他引:2
白背飞虱Sogatella furcifera(Horváth)为传播南方水稻黑条矮缩病病毒(SRBSDV)的媒介昆虫,阐明其传毒特性将有助于了解南方水稻黑条矮缩病的发生流行规律和建立相应的防治方法。本研究通过RT-PCR技术测定了白背飞虱的传毒参数。结果表明,白背飞虱初孵若虫、3龄若虫、5龄若虫、长翅型成虫和短翅型成虫的最短获毒时间分别是11、6、3、2和2min,最长获毒时间分别是19、12、9、8和8min。在26℃时,SRBSDV在不同虫态(初孵若虫、3龄若虫、5龄若虫、长翅型成虫和短翅型成虫)的白背飞虱体内的循回期分别是7~11、5~8、3~7、4~8和3~6d。5龄若虫、长翅型和短翅型成虫在三叶一心稻苗的最短接毒时间为4、5和6min,最长接毒时间为8、10和11min;它们在分蘖初期稻苗上的最短接毒时间分别是5、7和7min,最长接毒时间分别是10、12和12min。白背飞虱获毒后可终身传毒,但不能经白背飞虱卵传毒,单虫最多传毒株数为87株,平均传毒48.3±0.8株。可见,该虫具有较强的获毒能力和传毒能力,秧苗易感染SRBSDV。因此,在防治上应尽量清除田间SRBSDV毒源植物,减少白背飞虱获毒的机会,在秧田期和移栽初期应重点防治飞虱。 相似文献
97.
Seasonal abundance of macropterous Nilaparvata lugens and Sogatella furcifera based on presumptive macroptery in fifth-instar nymphs 总被引:1,自引:0,他引:1
Abstract. 1. The seasonal changes in abundance of macropterous N. lugens (Stal) and S. furcifera (Horvath) (Homoptera: Delphacidae) are described based on observed numbers of adults and presumptive macroptery in fifth-instar nymphs occurring in rice crops in the Philippines.
2. Percentage presumptive macroptery in fifth-instar nymphs was correlated with nymphal density over the range of 0–20 nymphs per hill for females of both species and 5–20 nymphs per hill for male N. lugens.
3. Lunar phase had no effect on wingmorph expression in either species.
4. Comparison of the percentage macroptery in fifth-instar nymphs with subsequent percentage macroptery in N. lugens adults for one season showed net emigration occurred from 60 DAT (days after transplanting) to harvest except for a period of net immigration lasting 7–10 days at approximately 95 DAT for both sexes. 相似文献
2. Percentage presumptive macroptery in fifth-instar nymphs was correlated with nymphal density over the range of 0–20 nymphs per hill for females of both species and 5–20 nymphs per hill for male N. lugens.
3. Lunar phase had no effect on wingmorph expression in either species.
4. Comparison of the percentage macroptery in fifth-instar nymphs with subsequent percentage macroptery in N. lugens adults for one season showed net emigration occurred from 60 DAT (days after transplanting) to harvest except for a period of net immigration lasting 7–10 days at approximately 95 DAT for both sexes. 相似文献
98.
ABSTRACT. 1. Daily trap catches of the rice planthoppers, N.lugens Stal and S.furcifera Horvath, and associated synoptic weather patterns were analysed in Kyushu, south-west Japan, in the autumns of 1980–85.
2. Certain weather patterns which seemed to favour overseas immigration, were reflected in trap catches: of eighteen occasions in which back-tracks on 850 mbar wind fields reached central China, marked mass catches in a light trap occurred on six occasions, and peaks in catch curves were found on another seven occasions.
3. These results strongly imply overseas immigration of the planthoppers from China to Kyushu in autumn, identical to invasions by the same species in early summer. However, such autumn migration is apparently non-adaptive because migrants or their progeny are soon killed by cold weather. 相似文献
2. Certain weather patterns which seemed to favour overseas immigration, were reflected in trap catches: of eighteen occasions in which back-tracks on 850 mbar wind fields reached central China, marked mass catches in a light trap occurred on six occasions, and peaks in catch curves were found on another seven occasions.
3. These results strongly imply overseas immigration of the planthoppers from China to Kyushu in autumn, identical to invasions by the same species in early summer. However, such autumn migration is apparently non-adaptive because migrants or their progeny are soon killed by cold weather. 相似文献
99.
Masaya Matsumura 《Population Ecology》1996,38(1):19-25
A population census was conducted to describe the effects of the growth stage of rice on the population dynamics ofS. furcifera, in particular, on immigration, seasonal abundance, population growth rate, and wing-form expression. The number of immigrants was highest on rice plants 17 to 30 days after transplanting (DAT), which suggested that immigrants prefer to settle or remain more on rice plants at the tillering stage (approximately 20–30 DAT). Population growth rate from immigration to the 1st generation decreased with an increase in rice plant age. In contrast, population growth rate from the 1st to 2nd generation was not influenced by rice plant age and was negatively density-dependent. The percentage of macropters (flyers) was positively related to the growth stage of rice when rice was in the vegetative or early part of the reproductive stage, and reached 100% at about 10 days before heading (booting stage). Threafter, most adult females molted into macropters regardless of population density. The roles of host plant age and crowding effect on the population dynamics ofS. furcifera are discussed. 相似文献
100.
为明确水稻品种和施肥时间对白背飞虱Sogatella furcifera (Horvath)卵被稻飞虱缨小蜂Anagrus spp.寄生率的影响,采用产卵苗诱集法和田间双因子设计进行实验研究。与秀水11水稻品种相比,协优413品种上的白背飞虱卵块位置较高且卵块较大。诱集实验表明白背飞虱卵的被寄生率显著受用于诱集的产卵水稻品种的影响, 在协优413上所产卵的被寄生率(24%)显著高于秀水11上的相应值(12%),而不受由田间品种和氮肥施用时间组合而形成的诱集苗所置放的栖境条件的影响。田间种植的水稻品种对其稻株上的白背飞虱卵被寄生率的影响大于施肥时间, 在卵高峰期,这种影响更为显著, 协优413上的被寄生率(17%)显著高于秀水11上的相应值(9%)。田间寄生率和诱集寄生率二者的反正弦平方根转换值间存在着极显著的直线相关。这些结果表明,水稻品种是加强白背飞虱自然生物防治的重要因子。 相似文献