全文获取类型
收费全文 | 835篇 |
免费 | 50篇 |
国内免费 | 25篇 |
专业分类
林业 | 23篇 |
农学 | 49篇 |
基础科学 | 16篇 |
54篇 | |
综合类 | 268篇 |
农作物 | 72篇 |
水产渔业 | 3篇 |
畜牧兽医 | 93篇 |
园艺 | 10篇 |
植物保护 | 322篇 |
出版年
2024年 | 4篇 |
2023年 | 8篇 |
2022年 | 19篇 |
2021年 | 19篇 |
2020年 | 30篇 |
2019年 | 28篇 |
2018年 | 16篇 |
2017年 | 40篇 |
2016年 | 46篇 |
2015年 | 25篇 |
2014年 | 51篇 |
2013年 | 63篇 |
2012年 | 60篇 |
2011年 | 55篇 |
2010年 | 27篇 |
2009年 | 39篇 |
2008年 | 35篇 |
2007年 | 41篇 |
2006年 | 36篇 |
2005年 | 40篇 |
2004年 | 39篇 |
2003年 | 38篇 |
2002年 | 21篇 |
2001年 | 27篇 |
2000年 | 11篇 |
1999年 | 19篇 |
1998年 | 11篇 |
1997年 | 14篇 |
1996年 | 6篇 |
1995年 | 12篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1982年 | 2篇 |
排序方式: 共有910条查询结果,搜索用时 296 毫秒
111.
112.
113.
40%苯苄乙草胺WP防除水稻抛秧田杂草效果研究 总被引:2,自引:1,他引:1
对40%苯苄乙草胺WP、10%苄嘧磺隆WP、50%苯噻酰草胺WP、20%乙草胺WP、60%苯噻苄WP防除水稻抛秧田杂草的效果进行研究.试验结果表明:40%苯苄乙草胺WP在水稻抛秧后5~7 d施药,可有效防除稗草、节节菜、矮慈菇、鸭舌草、异型莎草等各种稻田常见杂草,用药量600-750 g/hm~2,药后40 d对各类杂草总草株防效、鲜蕈防效分别达83.8%~88.6%、94.4%~96.4%,显著高于对照药剂60%苯噻苄WP 600 g/hm~2、10%苄嘧磺隆WP 300g/hm~2和50%苯嚷酰草胺WP750 g/hm~2防效. 相似文献
114.
为了探讨谷田阔叶杂草的化学防除技术,以冀谷25为试材,研究了喷施浓度225~450 mL/hm2的“削阔”水乳剂对谷田阔叶杂草的防治效果以及对谷子产量和经济效益的影响。结果表明:“削阔”水乳剂喷施浓度为450 mL/hm2时除草效果最好,且经济效益最高。 相似文献
115.
116.
高效氟吡甲禾灵108g/L乳油防除花生田1年生禾本科杂草药效试验 总被引:1,自引:0,他引:1
试验结果表明,高效氟吡甲禾灵108g/L乳油16.2、32.4、48.6、64.8g/hm2共4个处理对1年生禾本科杂草马唐的防效分别达到83.6%、96.5%、92.2%、91.1%。在花生田1年生禾本科杂草2叶期~生长盛期用高效氟吡甲禾灵108g/L乳油进行茎叶处理,施药量以32.4~48.6g/hm2(商品量20~30mL/667m2)为宜,药后45d防效仍可保持在90.0%以上。推荐剂量下药剂对花生生长安全。 相似文献
117.
[目的]研究三氟啶磺隆防除细叶结缕草草坪杂草的效果、杀草谱、合理使用剂量及其对草坪的安全性,为大面积生产应用提供科学依据。[方法]采用单因素随机区组试验设计,在细叶结缕草草坪上,用100 g/L三氟啶磺隆OD 300~750 ml/hm2进行茎叶喷雾处理防除杂草研究。[结果]600~750ml/hm2的100 g/L三氟啶磺隆OD能有效防除酢浆草,其防效优于对照药剂25%秀百宫WDG;也能够较好地防除单穗水蜈蚣等莎草科杂草,对马唐也有一定的抑制效果,防效接近对照药剂25%秀百宫WDG;对两耳草、母草、粗叶耳草等防效相对较差;对成坪的细叶结缕草生长无影响,对草坪安全。[结论]在细叶结缕草草坪上使用600~750ml/hm2的100 g/L三氟啶磺隆OD较为适宜。 相似文献
118.
Buffer strips are refuges for a variety of plants providing resources, such as pollen, nectar and seeds, for higher trophic levels, including invertebrates, mammals and birds. Margins can also harbour plant species that are potentially injurious to the adjacent arable crop (undesirable species). Sowing perennial species in non‐cropped buffer strips can reduce weed incidence, but limits the abundance of annuals with the potential to support wider biodiversity (desirable species). We investigated the responses of unsown plant species present in buffer strips established with three different seed mixes managed annually with three contrasting management regimes (cutting, sward scarification and selective graminicide). Sward scarification had the strongest influence on the unsown desirable (e.g. Sonchus spp.) and unsown pernicious (e.g. Elytrigia repens) species, and was generally associated with higher cover values of these species. However, abundances of several desirable weed species, in particular Poa annua, were not promoted by scarification. The treatments of cutting and graminicide tended to have negative impacts on the unsown species, except for Cirsium vulgare, which increased with graminicide application. Differences in unsown species cover between seed mixes were minimal, although the grass‐only mix was more susceptible to establishment by C. vulgare and Galium aparine than the two grass and forb mixes. Annual scarification can enable desirable annuals and sown perennials to co‐exist, however, this practice can also promote pernicious species, and so is unlikely to be widely adopted as a management tool in its current form. 相似文献
119.
Moving integrated weed management from low level to a truly integrated and highly specific weed management system using advanced technologies
下载免费PDF全文
![点击此处可从《Weed Research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Integrated weed management (IWM) is one of the most commonly referred to approaches for sustainable and effective weed control in agriculture, yet it is not widely practiced, likely because current IWM systems fail to meet performance expectations of growers. The effectiveness and value of IWM systems should increase with increasing application specificity and true integration made possible with contemporary advances in technology, information systems and decision support. IWM systems can be classified based on their degree of application specificity and level of integration of tactics. In the application specificity pathway, a tactic is applied at a range of scales, from subfield to plant specific. In the integration pathway, multiple weed control tactics are combined in a synergistic manner. We hypothesise that the full value of IWM can and will be realised only when current and emerging technological innovations, information systems and decision tools are synergistically combined for use in real time. The True IWM system we envision requires automation and robotic technologies, coupled with information and decision support systems that are available or emerging but not yet enabled, in a proven integrated platform. Examples of low‐level, traditional and precision IWM systems are discussed, and research needs for a True IWM system are presented. We conclude that the immediate call should be for a long‐term investment in R&D and education (both theoretical and empirical) to develop and implement True IWM systems, an effort best accomplished in a public–private partnership where all essential entities are fully engaged and adequately resourced, including growers from all countries who will utilise IWM. 相似文献
120.
Globalisation and increasing trade have led to the introduction of alien plants that are highly competitive and difficult to control in agriculture in central Europe. Our study set out to analyse the invasion process and agricultural impact of the six emerging alien plants Abutilon theophrasti, Ambrosia artemisiifolia, Cyperus esculentus, Datura stramonium, Panicum schinzii and Sorghum halepense in Austria, based on a large distribution data set (694 occurrence records in crop fields). We found that all study species have increased in abundance and range, especially after the year 2000. The rate of spread was highest for A. artemisiifolia and lowest for C. esculentus. At present, records of the study species were largely associated with areas of high summer crop concentration in eastern, southern and north‐western Austria. Based on the CORINE land‐cover data set, we found that the agricultural area at risk of being invaded increased over time. At present, it ranges between 45 500 and 168 000 ha (approximately 2.4% and 8.7% of the total agricultural area) depending on the species. The invasion success of the study species is probably associated with frequent human‐mediated dispersal, specific crop‐dominated rotations and herbicide use. Our results suggest that the study species will successfully spread further. We conclude that these emerging alien species will cause substantial impacts on crops in Austria and probably in other countries of central Europe. 相似文献