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991.
992.
厚皮甜瓜嫁接防治枯萎病试验研究 总被引:1,自引:3,他引:1
利用嫁接防治枯萎病在西瓜生产中已普及,但在甜瓜上应用较少。本试验以10种砧木为试材,拟为甜瓜嫁接栽培筛选适宜的砧木。嫁接防病试验结果表明,采用地方瓜种1笋瓜和日本新土佐南瓜等10种砧木嫁接海蜜3号甜瓜,可显著提高甜瓜的抗枯萎病能力,除菜瓜和永康组合有少许发病株外,地方瓜种1和新土佐组合防病效果均达100%,而对照海蜜3号自根嫁接植株的病株率为8.5%;亲和性,新土佐组合好于自根嫁接的对照,地方瓜种1组合总体上逊于对照;667m2产量新土佐超过对照116kg,地方瓜种1超过对照142kg;地方瓜种1组合与对照果肉质地、颜色相近,可溶性固形物含量高于对照,新土佐组合果实质地软,口感较淡,可溶性固形物含量略低于对照。地方瓜种1和日本新土佐可作为海蜜3号甜瓜的砧木在生产上应用。 相似文献
994.
Wayne?W.?FishEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(1):67-76
Netted cantaloupe (Cucumis melo var. cantalupensis cv. Magnum 45) were harvested from 5 to 35 days postanthesis. The fruit of each age group were divided into exocarp, outer mesocarp, mid mesocarp, inner mesocarp, placenta, and seed. Each tissue was extracted and assayed for polygalacturonase-inhibiting protein (PGIP) activity against polygalacturonases (PGs) from three fungal pathogens of cantaloupe fruit. The PGIP activity of all tissues except placenta was high from the flower stage through the first week of fruit development but decreased markedly between 5 and 10 days postanthesis. PGIP activity against Phomopsis cucurbitae PG remained high and nearly constant in placental tissue throughout fruit development. However in this same tissue, PGIP activity against Fusarium solani PG decreased during fruit development to about 25% of its level in the 5-day-old fruit. This differential change in PGIP activity toward the two PGs suggests that different forms of the inhibitor are expressed between early and late stages of cantaloupe fruit development. The results also illustrate the importance of using multiple pathogen enzyme systems that can provide an opportunity for more accurate elucidation of mechanisms involved in the host–pathogen interaction. Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture. All programs and services of the US Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap. The article cited was prepared by a USDA employee as part of his/her official duties. Copyright protection under US copyright law is not available for such works. Accordingly, there is no copyright to transfer. The fact that the private publication in which the article appears is itself copyrighted does not affect the material of the US Government, which can be freely reproduced by the public. 相似文献
995.
Dorette?Müller-St?verEmail author Holger?Buschmann Joachim?Sauerborn 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(3):193-202
Fusarium oxysporum Schlecht. f.sp. orthoceras (Appel & Wollenw.) Bilai is a potential biocontrol agent against the root-parasitic weed Orobanche cumana. In pot experiments with different sunflower cultivars, the application of F. oxysporum was combined with a treatment of BTH (Benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester), a product known to induce resistance against O. cumana in sunflower. The combined treatments resulted in highly reliable control and sometimes in increased control level compared to the Fusarium treatment alone. In laboratory experiments, no enhancing effect of BTH on virulence and growth of the fungus was observed. Future experiments should further investigate the basic mechanisms of the effect achieved by combining the two control strategies as well as the transfer of this innovative control approach into field experiments. 相似文献
996.
西瓜枯萎病是西瓜产业中最为重要的土传病害之一,利用抗病品种仍然是最理想的防治途径,然而新培育的抗病品种引入其他地区后抗性容易丧失,因此了解新品种抗性特点有助于品种推广应用。本试验通过菌土接种法鉴定了8 个西瓜品种对枯萎病生理小种1 的抗性,并利用分子标记进行验证。结果显示,6 个供试西瓜新品种表现为中抗,与分子标记检测结果一致。其中申选958、申蜜968 和申蜜6 号在3 次不同时间的重复试验中抗性表现差异较大,表明其抗性对环境因子尤其是温度和湿度较敏感。申抗988 与申选958 具有相同的抗病亲本,且分子标记检测基因型一致,但在相同环境条件下二者抗性表现差异也较大,表明由于亲本材料不同,品种间可能存在不同的微效基因或基因互作方式。 相似文献
997.
由丝核菌引起的十字花科蔬菜叶腐和茎基腐病在中国华北地区普遍发生,其中以河北、内蒙以及北京较为严重。2011~2018年,从华北地区不同省份具有典型叶腐和茎基腐症状的芸苔属蔬菜上分离获得95个丝核菌(Rhizoctonia spp.)分离物,大多数分离自发病植株的叶部,少数分离自茎基部。通过细胞核染色,87株菌属于多核丝核菌,另外8株属于双核丝核菌;经菌丝融合鉴定、rDNA-ITS区及TEF-1α(translation elongation factor 1-alpha, TEF-1α)序列分析,大多数多核丝核菌属于立枯丝核菌(Rhizoctonia solani)AG-2-1(74%),其他少数分别属于AG-1-IB(16%)、AG-4-HG II(2%)和双核丝核菌AG-A(8%)。温室条件下进行寄主范围致病力测定,各分离物对原寄主都表现出致病力,呈现典型叶腐或茎基腐症状;对其他作物的致病力差异较大。不同融合群(Anastomosis group,AG)的菌株对寄主致病力大小存在差异,AG-2-1致病力最强,只有AG-A对叶部没有致病力。AG-2-1对寄主叶部的致病力和对茎基部的致病力呈显著正相关,AG-1-IB对寄主叶部的致病力和对茎基部的致病力无显著相关性。 相似文献
998.
999.
新疆棉花枯萎病菌优势生理小种及其致病型研究 总被引:5,自引:0,他引:5
1996~1998年,我们陆续从新疆各主要棉区采集和收集400余株病株样,共分离获得108株棉花枯萎病菌,对其中具有代表性菌株致病性和生理性状研究结果表明,新疆棉花枯萎病菌优势小种仍为7号生理小种,但其致病性较强,新疆棉花枯萎病菌致病型主要分为强、弱2种致病型,强致病型主要分布于南北疆棉区,弱致病型主要分布于东疆棉区。供试棉花枯萎病菌菌系在25℃培养7 d后,菌丝为白色,菌落皿底产生色素多为紫色或浅紫色,大分生孢子为10.4~44.2 μm×2.0~6.1μm,多为马特型,最适生长温度为25℃,除供试6个菌系能在35℃缓慢生长外,多数棉花枯萎病菌菌系30℃以上不易生长,吐鲁番菌系HAI-17在40℃仍能缓慢生长,新疆棉花枯萎病菌较耐高温,在40、45℃高温下并未致死。目前,尚未发现3号生理小种。 相似文献
1000.
Bayoud, caused by the soilborne fungusFusarium oxysporum f.sp.albedinis (FOA), is the most serious disease of date palm. Since the disease is located in the North African countries of Morocco and
Algeria, and advancing steadily eastwards, the ultimate goal is to prevent spread of the pathogen to other date-growing areas
in the region and farther afield. Molecular diagnostic techniques have been developed for detection of FOA. In view of the
fact that the fungus does not exist in Israel, DNA of FOA was obtained to determine the reliability of these methods for diagnostic
purposes. Random amplified polymorphic DNA was not reliable enough for differentiation between FOA and various pathogenic
and saprophyticFusarium isolates. However, the polymerase chain reaction utilizing FOA-specific primers was accurate and enabled amplification of
a unique band specific to FOA DNA alone, and not that of the other tested pathogenic and saprophyticFusaria. The availability of a rapid and reliable diagnostic tool for detection of FOA will enable the Plant Protection and Inspection
Services of the Israel Ministry of Agriculture to test date palm tissue for the presence of the pathogen.
Contribution no. 513/00 from the Inst. of Plant Protection, ARO, The Volcani Center, Bet Dagan, Israel. 相似文献