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231.
为了解育成抗病品种抗性稳定性及胞囊线虫生理小种侵染力的变异,于2005~2008年,应用黑龙江省发生的大豆胞囊线虫3号生理小种及已经通过鉴定的抗大豆胞囊线虫3号生理小种的品种,哈尔滨小黑豆、灰皮支等8个品种和感病对照品种Lee68为材料,进行抗病基凶对大豆胞囊线虫3号生理小种选择作用研究.在盆栽条件下,强迫大豆胞囊线虫3号生理小种的群体在抗病品种上繁殖10代,选用5个标准鉴定大豆胞囊线虫生理小种的鉴别品种,重新鉴定经抗病基因选择后的大豆胞囊线虫的生理小种类型.结果表明:原来为3号生理小种的线虫群体,经在抗病品种抗线虫1号、抗线虫2号、抗线虫3号、抗线虫4号、抗线虫5号上连续选择10代之后,变为6号小种;经在厌皮支黑豆上选择之后变为10号小种;经在Peking上选择之后变为14号小种,经在哈尔滨小黑豆上选择之后变为15号小种.上述鉴定结果说明,原大豆胞囊线虫生理种群体,经过在抗病品种上连续强迫繁殖后,形成新的生理小种,并使原扰病品种变为感染品种,认为在生产上采用轮作方式是保持抗线品种抗性稳定性的有效途径. 相似文献
232.
灰皮支黑豆抗大豆胞囊线虫3号生理小种的生理机制 总被引:1,自引:0,他引:1
以抗感大豆胞囊线虫3号生理小种品种灰皮支黑豆(ZDD2315)和辽豆15为材料,室内人工接种大豆胞囊线虫,接种后5、10、15、20、25、30 d取样,测定抗感品种接种与未接种根内丙二醛(MDA)、可溶性糖和可溶性蛋白含量的动态变化,初步明确灰皮支黑豆抗大豆胞囊线虫3号生理小种的生理机制.结果表明:大豆受大豆胞囊线虫侵染后,抗病品种灰皮支黑豆根内丙二醛(MDA)、可溶性糖含量低于感病品种辽豆15,而可溶性蛋白含量高于感病品种辽豆15. 相似文献
233.
江苏省小麦孢囊线虫病发生情况初步调查 总被引:6,自引:1,他引:5
2009年5月对江苏省5个地区的22个县市小麦孢囊线虫病发生情况进行了初步调查,共采集76份含根系和根际土壤的样本,经分离与鉴定表明,小麦禾谷孢囊线虫(Heterodera avenae,CCN)在徐州、连云港、宿迁和盐城等地区都有分布,检出率为35%。徐州的沛县、丰县、邳州和睢宁等4个县市的小麦孢囊线虫病检出率超过90%。其中,丰县华山镇、沛县河口镇和丰县城东的田块孢囊密度较大,每100 mL土壤的平均孢囊数分别为161、159个和112个,每个孢囊的平均含卵量分别为187、190粒和174粒。这是小麦孢囊线虫病在江苏省发生的首次报道。 相似文献
234.
Worldwide, cyst nematode (SCN) Heterodera glycines is the most destructive pathogen on cultivated soybean (Glycine max (L.) Merr.). In the USA yield losses in 2001 were estimated to be nearly 60 million dollars. Crop losses are primarily reduced
by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars
overtime because resistance primarily traces to two soybean accessions. Recently cv. Hartwig was released which has comprehensive
resistance to most SCN populations. A virulent nematode population LY1 was recently selected for its reproduction on Hartwig.
LY1 population originated from a mass mating of Race 2 (HG Type 1.2.5-) females with Race 5 (HG Type 1.2-) males. LY1 nematode
population infects currently known sources of resistance except PI 567516C. The female indices obtained on PI 567516C and
Hartwig were 7% (resistant) and 155% (susceptible), respectively. However, the genetic basis of LY1 resistance in soybean
PI 567516C is not known. Resistant PI line 567516C was crossed to susceptible cultivar Hartwig to generate 105 F2:5 families. These families together with parents, seven indicator lines and a susceptible control cv. Lee-74 were evaluated
for response to LY1 nematode population in the greenhouse. Chi-square analysis showed resistance in PI567516C to LY1 was conditioned
by one dominant and two recessive genes (Rhg, rhg, rhg). Chi-square value was 0.15 and P = 0.70. This information will be useful to soybean researchers for developing resistant cultivars to nematode population
that infects Hartwig. 相似文献
235.
以往大豆孢囊线虫采用生理小种来划分不同群体对大豆致病力的差异,最近美国采用了新的分类系统-HG类型,将用此分类系统代替原来的生理小种分类系统。本文介绍了HG类型的命名原则、鉴别寄主、标准感病品种、鉴定标准(环境、种子、接种物制备、盆栽容器和土壤)以及HG类型的用途等。 相似文献
236.
The effect of soybean cyst nematode (SCN) race 3 and strains of Bradyrhizobium japonkum interactions on nodulation and other agronomic characters of several soybean genotypes was investigated. Nodule weight was reduced in soybean cultivar Ogden treated with SCN plus Bradyrhizobia strains USDA 110 and 6 and on soybean cultivar Essex treated with SCN plus strain USDA 6. The result was reversed on soybean cultivar Essex treated with SCN plus strain USDA 110. The nodule number also decreased on soybean cultivars Ogden and Essex treated with SCN plus strains USDA 110 and 6. The fresh root weights of soybean cultivars Ogden and Essex treated with SCN plus strain USDA 110 were heavier than the fresh root weight of Essex treated with SCN plus strain USDA 6. Lower nitrogen content of stems and leaves was noted only in cultivar Essex treated with SCN plus strains USDA 110 and 6. Bradyrhizobia strain USDA 110 was more efficient in the initiation of nodules in cultivars Ogden and Essex than strain USDA 6. The nitrogen-fixing capacity of strain USDA 6 in Ogden was better than strain USDA 110. The differences in the agronomic performances of the various soybean genotypes were due to their degree of susceptibility to SCN and Bradyrhizobia strains and also to their genetic make-up. 相似文献
237.
238.
对吉林省36个县(市)330块大豆地进行了抽样调查和分离鉴定,结果表明:34个县(市)有大豆孢囊线虫病发生,占调查总数的94%。该病在柳河、长岭、镇莱、白城和靖宇发生严重,扶余、吉林、舒兰、通榆、农安、榆树、德惠、磐石次之。按照Golden鉴定大豆孢囊线虫生理小种的方法,用五个国际上的标准鉴别寄主即Peking,PI88788,PI90763,Pickett和感病对照品种Lee对吉林省孢囊线虫发生较重的地块分得的线虫进行了生理小种鉴定,结果分析表明:吉林省大豆孢囊至少存在两个生理小种,即3号和7号小种,其中3号小种出现频率较高,是吉林省大豆孢囊线虫的优势小种。 相似文献
239.
Monosomic sugar beet/wild beet addition lines (2n = 19) with full resistance against the beet cyst nematode have been characterized in different ways. Within the B. procumbens and B. webbiana addition lines three groups could be classified according to their isozymes pattern, growth habit, transmission rate, and resistance level. It is assumed that B. procumbens and B. webbiana each possess three different chromosomes which carry genes for nematode resistance. In the offspring of the addition lines diploid translocation types appear at very low frequencies, Isozyme pattern or growth type of the resistant plants were used for selecting diploid types in the offspring of monosomic addition lines. Effective selection could be made in progenies of susceptible sugar beets pollinated by addition lines because the pollen transmission of the alien chromosome is very low. Using these methods 7 nematode-resistant sugar beet lines could be selected. The transmission rates of the resistance gene ranged from 70.6% to 100%. Threw heterozygous progenies showed a 1:1 segregation indicating monogenic dominant inheritance of resistance. The level of resistance was as high as in the addition lines. 相似文献
240.