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51.
经一年的田间试验,在西双版纳网棚无土栽培条件下,采用在网棚下增置防雨塑料棚和多种农药组合的6种处理,对幼苗期和产花期细菌性叶疫病表现出有不同程度的防效,但防效较低(10.6%-61.1%), 不能有效抑制病害累计死亡率的快速增长和全部死亡;经研究提出了在现有的栽培条件下,实施“无菌”栽培策略,调整栽培技术思路的建议。 相似文献
52.
红掌不同品种产生愈伤组织的差异 总被引:7,自引:0,他引:7
对10个红掌品种2种外植体、4种愈伤组织诱导培养基的组培试验结果:H3、H4、H10、H6、H1等5个品种愈伤组织的平均直径(叶片外植体依次为5.0~3.8mm,叶柄外植体依次为6.6~4.9mm)明显大于H5、H2、H9、H8、H7等5个品种(叶片外植体均为1.0mm,叶柄外植体依次为1.2~2.0mm);叶柄外植体愈伤组织平均直径明显大于叶片外植体;参试培养基B、D产生愈伤组织的直径大于培养基A、C;愈伤组织大的5个品种经增殖、继代培养成完整植株,而愈伤组织小的5个品种愈伤组织在增殖培养中逐渐褐变,全部死亡。 相似文献
53.
影响红掌愈伤组织诱导、增殖和芽分化的因素 总被引:17,自引:0,他引:17
以Pink champion等盆栽植株和试管苗为材料,研究了影响红掌愈伤组织诱导、增殖和芽分化的因素。结果表明,不同品种的愈伤组织诱导率和外植体褐变率均存在显著差异,诱导率和褐变率之间呈显著的负相关关系。外植体、外源激素和培养基对愈伤组织的诱导有显著影响,不同品种和外植体的适宜诱导培养基不同。光照对愈伤组织的诱导有显著的抑制作用;高浓度生长素、低浓度细胞分裂素,促进愈伤组织的增殖,高浓度细胞分裂素及低浓度生长素促进愈伤组织芽分化;固体培养比液体培养更有利于愈伤组织的增殖和芽分化。 相似文献
54.
Surassawadee Promyou Saichol Ketsa Wouter G. van Doorn 《Postharvest Biology and Technology》2012,64(1):104-110
We tested if salicylic acid (SA) can alleviate chilling injury in anthurium flowers (Anthurium andraeanum). Cut flowers of five cultivars, individually placed in water, were held at 4 °C and 12 °C. Symptoms of chilling injury (CI) were found in the flowers stored at 4 °C. These symptoms included desiccation of the spadix (the compound floral stalk) and a colour change of the spathe (the large floral bract) to pink and then to brown. The time to the CI symptoms depended on the cultivar. CI symptoms were accompanied by an increase in electrolyte leakage, by loss of fresh weight, and by an increase in catalase (CAT) and superoxide dismutase (SOD) activity. SA at 2.0 mM in water was applied as a 15 min dip. It delayed the CI symptoms, as well as the loss of fresh weight, the increase in electrolyte leakage, and the increase CAT and SOD activity. The data suggest that CI in this system is related to an increase in the concentrations of active oxygen species. 相似文献
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57.
Bai Jing-shu Zhu Xiao-qing Li Feng-lan Guo Hui-hong Li Zhi-dan College of Biological Sciences Biotechnology Beijing Forestry University Beijing P. R. China North National Forest Plantlet Exemplary Base Beijing P. R. China 《中国林学(英文版)》2005,7(1)
The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum “Arizona" and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium’s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically sub- tended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers’ cells degenerated completely dur- ing meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflores- cences stay at their fifth development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage. 相似文献
58.
The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum ““Arizona““ and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium‘s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically subtended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers‘ cells degenerated completely during meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflorescences stay at their fiRb development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage. 相似文献
59.
CO2 浓度升高对红掌光合速率与生长发育的影响 总被引:10,自引:1,他引:10
本试验以开顶式塑料薄膜温室为设施, 研究了高CO2 浓度对红掌叶片光合速率、植株生长、光合酶活性和花期的影响。结果表明: 处理90 d时, 对照组〔大气CO2 浓度( 360 ±30) μmol·mol- 1 〕红掌的株高、叶面积、株干样质量、株鲜样质量与处理前相比分别增加了16.4%、36.1%、101.2%和84.2% , 而高CO2 浓度组〔( 1 000 ±100 ) μmol·mol- 1 〕则分别增加了72.9%、65.6%、217.6%和199.1%。高CO2 浓度组的净光合速率比对照增加46.27%, 气孔导度下降, 促进了叶片中可溶性糖和淀粉积累, 叶绿素含量比对照下降, 而对Rubisco活性影响较小, 乙醇酸氧化酶活性则明显下降。高CO2 浓度处理50 d时, 开花率为25%, 处理90 d时已达到80%以上, 而在整个试验期间对照组未见开花。因此, 高浓度CO2 处理提高了红掌叶片的光合速率和碳水化合物的积累, 促进了营养生长, 提前了花期。 相似文献