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81.
野生黄花苜蓿叶肉原生质体培养和植株再生 总被引:14,自引:7,他引:7
取野生黄花苜蓿15~20天叶龄的叶片,去掉下表皮,用1%纤维素酶、1%半纤维素酶和0.5%果胶酶的混合液游离原生质体。用改良的MS培养基附加2,4-D、BA和NAA等,在黑暗条件下浅层悬浮培养。培养第4天、第7天和第10天,原生质体分别出现第一次、第二次和多次分裂,在此期间数次加液或换液调节渗透压,直至形成1mm左右的大细胞团,然后转移到附加2,4-D和KT等的MS固体培养基,诱导形成愈伤组织,再经4~5次继代培养,分化成为完整的再生植株。 相似文献
82.
孙振久 《西北农林科技大学学报(自然科学版)》1993,21(1):100-102
将0.5%纤维素酶Rs+0.1%果胶酶Y-23酶溶液振荡处理3h,可得到最高的细胞分裂率,但原生质体分离数量较低。0.5%纤维素酶R-10+0.05%离析酶R-10+0.05%果胶酶Y-23酶溶液,25℃下处理14h,原生质体分离数量及细胞分裂率均较高。1/2MS培养基添加NAA3mg/L+BA0.5mg/L+2,4-D 0.1mg/L的液体培养基有利于细胞团形成及愈伤组织生长。本试验获得了完整的再生植株,芽分化率达20%左右。 相似文献
83.
原生质体在作物改良上的应用 总被引:4,自引:0,他引:4
植物原生质体(protoplast)是除去细胞壁而仅为原生质膜所包围的裸露细胞.由于失去了细胞壁这个屏障,因而使其具有了一般植物细胞所不具备的优点,不仅成为植物生理学、细胞生物学、体细胞遗传学等理论研究的理想材料,而且也成为生物工程及作物改良的有效手段,本文在参考大量文献资料的基础上,从原生质体融合、遗传转化、无性系变异及超低温保存等几个方面综述了原生质体应用于作物改良的特点及研究现状,展望了其应用前景. 相似文献
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87.
Kazutaka Kido Tomofumi Mochizuki Kazutoshi Matsuo Chika Tanaka Kenji Kubota Takehiro Ohki Shinya Tsuda 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):189-194
The single recessive gene, nsv, which confers resistance against Melon necrotic spot virus (MNSV), has recently been used to develop virus-resistant melon cultivars in Japan. However, the Chiba isolate of MNSV, a
common isolate in Japan, infected resistant cultivars when inoculated melon plants were grown at 15°C. Viral RNAs accumulated
in protoplasts from resistant cultivars at both 15 and 20°C. Mechanical inoculation of the cotyledons caused MNSV to spread
throughout the leaves at 15°C, but not at 20°C. These results support our novel hypothesis that a temperature-sensitive inactivation
of disease resistance genes occurs at the nsv locus in melon cultivars with the resistance gene grown at temperatures below 20°C.
The first and second authors contributed equally to this research. 相似文献
88.
利用原生质体融合技术构建梨孢属融合子的研究方法初探 总被引:1,自引:0,他引:1
鉴于有性世代形成能高的稻瘟病菌菌株有限,稻瘟病菌间的杂交组合难于获得,从而很难对一些重要基因,如无毒基因,抗药性基因等进行遗传分析及深入研究.本研究利用原生质体融合技术获得梨孢菌的杂合子,从而评价该体系用于遗传研究的可行性.首先,利用转基因技术获得稻瘟病菌Y93-164a-1跟蟋蟀草病菌SA98-4的抗药性转化子,然后将两个菌的稳定转化子的原生质体进行融合,之后进行连续5次的继代培养,最后进行3次单孢分离来挑选稳定的融合子.结果表明,利用原生质体融合技术在两个不同致病型的梨孢菌之间能获得稳定的融合子,初步表明利用原生质体融合技术组建梨孢菌的融合子群体用于遗传分析在技术上是可行的.Abstract: The genetic analysis of important genes, e. g. avirulence genes, antibiotic resistant genes in Magnaporthe oryzae pathogens had been limited because of the difficulty of getting highly fertile strains for genetic cross, especially in Oryza pathotype strains. In the present study, an alternative method for the genetic study of this fungus was tried by using the protoplast fusion system. Firstly, drug-resistant transformants were generated from the Oryza strain Y93-164a-1 and Eleusine pathotype strain SA98-4, then protoplasts of both selected transformants were fused by protoplast fusion technique. Stable fusants were selected after at least five subcultures and three single-spored isolations on the selective medium. Results suggested that the stable fusants can be easily obtained by protoplast fusion system, showing the protoplast fusion system could be usable for genetic analysis of M. oryzae pathogens. 相似文献
89.
Yasunori Akagi Masatoki Taga Mikihiro Yamamoto Takashi Tsuge Yukitaka Fukumasa-Nakai Hiroshi Otani Motoichiro Kodama 《Journal of General Plant Pathology》2009,75(2):101-109
To analyze the genetics of host-specific toxin production and its relation to the specific pathogenicity of a mitosporic fungus
Alternaria alternata, we developed a protoplast fusion system. Protoplasts of drug-resistant transformants of the A. alternata tomato pathotype (AAL-toxin producer) and A. alternata strawberry pathotype (AF-toxin producer) were fused by electrofusion. Of five fusion strains examined, two strains were pathogenic
on both tomato and strawberry host plants, whereas the rest of the fusion strains were pathogenic only on tomato. Pulsed-field
gel electrophoresis analysis demonstrated that the hybrid strains pathogenic on both tomato and strawberry carry 1.0- and
1.05-Mb conditionally dispensable (CD) chromosomes derived, respectively, from the parental strains of the tomato and strawberry
pathotypes. On the other hand, the fusion strains appeared to maintain only a single homologous chromosome derived from one
of the parental strain in the case of essential chromosomes (A chromosomes). The results suggest that fusion strains between
two different pathotypes of A. alternata might be haploid resulting from the deletion of extra sets of essential chromosomes in the fused nuclei, whereas the CD chromosomes
derived from each parental strain could be maintained stably in a new genetic background with an expanded range of pathogenicity.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank database under the accession numbers AB469331to
AB469354. 相似文献
90.
[目的]筛选软枣猕猴桃原生质体最佳酶解液配方。[方法]以4种配方酶解液在相同条件下处理等量软枣猕猴桃叶片,比较最后收集的纯化原生质体量,筛选最佳酶解液配方。[结果]配方Ⅲ(1.0%纤维素酶、0.5%离析酶、0.3%果胶酶)和Ⅳ(1.0%纤维素酶、0.5%果胶酶)处理酶解效果要明显优于配方Ⅰ(2.0%纤维素酶、0.5%离析酶)、Ⅱ(2.0%纤维素酶、0.3%果胶酶)。[结论]配方Ⅲ(1.0%纤维素酶、0.5%离析酶、0.3%果胶酶)为软枣猕猴桃原生质体最佳酶解液配方。 相似文献