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101.
A new and efficient method for clonal propagation of Casuarina sumatrana by rooting stem cuttings is described. High percentage (about 60–70%) of rooting was achieved with mature softwood stem cuttings. A quick-dip of 5 s in NAA (1–10mM) solution followed by sand culture under high humidity were required for a high rate of survival and rooting of stem cuttings. A simple, closed chamber propagation system, using fluorocarbon polymer (tetrafluoroethyleneperfluoroalkyl vinyl ether) film (Neoflon PFA film), was successfully developed for the rooting of stem cuttings without mist. Rooted cuttings inoculated with Frankia were easily transplanted and established in field conditions with very low (about 3%) mortality. The significance of these findings for mass clonal propagation of C. sumatrana is discussed.Abbreviations IBA
indole-3-butyric acid
- NAA
-naphthaleneacetic acid 相似文献
102.
Direct shoot formation and plant regeneration from cotyledon explants of rapid-cycling Brassica rapa
Winnie Teo Prakash Lakshmanan Prakash Kumar Chong-Jin Goh Sanjay Swarup 《In vitro cellular & developmental biology. Plant》1997,33(4):288-292
Summary An in vitro culture system for direct shoot regeneration from cotyledon explants of rapid-cycling Brassica rapa was developed. Cotyledons from 3-d-old seedlings, when cultured on Murashige and Skoog (MS) medium supplemented with 20 μM N6-benzyladenine (BA) and 2 μM α-naphthaleneacetic acid (NAA), regenerated shoots directly at a frequency of 20%. The addition of 2 μM aminoethoxyvinylglycine (AVG) to this medium increased shoot regeneration to 33%, but silver nitrate drastically inhibited
shoot regeneration. Shoot regeneration occurred directly, at the petiolar cut ends of cotyledonary explants, between 10 to
17 d in culture. The highest percentage of regeneration (33%) was obtained from 3-d-old seedlings. NAA was the most effective
auxin for root induction and development, with 49% of shoots producing roots after 2 wk on medium containing 1.0 μM NAA. Regenerated plantlets were grown to maturity in pots containing peat moss and vermiculite (1:1). These plants were morphologically
normal and fertile. With this protocol, over 100 independently derived, flowering R0 plants were obtained from 40 regenerating cotyledonary explants within 40 d after culture initiation. 相似文献
103.
Giovanni Iapichino 《In vitro cellular & developmental biology. Plant》1996,32(4):249-252
Summary Side shoots excised from underground dormant buds ofCynara scolymus L. were used as primary explants to establishin vitro cultures. A 3×3 factorial experiment with all possible combinations of three concentrations (0.5, 1.0, 2.0 mg/liter or 2.22,
4.44, 8.88 μM) ofN
6-benzyladenine (BA) and three concentrations (0, 0.1, 0.2 mg/liter or 0, 0.54, 1.07 μM) of 1-naphthaleneacetic acid (NAA) was used to determine the optimum growth regulator combination for shoot multiplication.
The highest rate of axillary shoots was induced on Murashige and Skoog agar medium supplemented with 0 mg NAA/liter and 1.0
mg BA/liter (4.44 μM). Other cytokinins tested (kinetin, zeatin, and 2-isopentenyl-adenine were less effective than BA in inducing axillary shoot
growth. Up to 60% of elongated microshoots rooted after 5 weeks on 1/2 MS agar medium supplemented with 2 mg/liter (11.42
μM) indole-3-acetic acid (IAA). Seventy percent of rooted plantlets were transferred successfully into soil. Plants are under
evaluation for their genetic uniformity and clonal fidelity. 相似文献
104.
Heloir Marie-claire Fournioux Jean-Claude Oziol Lucie Bessis Roger 《Plant Cell, Tissue and Organ Culture》1997,49(3):223-225
A method has been developed for rapid propagation in vitro of Vitis vinifera cv. 'Pinot noir' from axillary-bud microcuttings
harvested from plantlets initially cultured in vitro. The requirement of plant growth regulators for the different stages
of the micropropagation was examined. BA at 8.9 μM added to MS basal medium was found to be optimal for culture establishment,
while for subcultures, the concentration of BA was reduced to 4.4 μM to prevent hyperhydricity. Among the two auxins (NAA
and IBA) tested for rooting, IBA at 2.5 μM was found to induce a good rooting- system in 100% of the shoots. The advantages
of this method, using microcuttings from established plants in vitro, is discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
105.
Rooting, growth and ethylene evolution of pea cuttings in response to chloroindole auxins 总被引:3,自引:0,他引:3
In pea cuttings ( Pisum sativum L. cv. Alaska) we measured shoot and root growth and ethylene production in response to 4-chloroindole-3-acetic acid (4-CI-IAA) or 4,6-dichloroindole-3-acetic acid (4,6-Cl2 -IAA). Leafy cuttings treated basally with either of the chlorinated auxins in high concentrations showed permanent epinasty, loss of apical growth and dominance resulting in the outgrowth of laterals from the lower-most axillary bud. The naturally occurring 4-CI-IAA was a better root promoter than the synthetic 4,6-Cl2 -IAA which inhibited rooting. Both chloroindole auxins induced very high ethylene evolution, which lasted much longer than the ethylene evolution after IAA treatment. 相似文献
106.
107.
N fertilizer recommendatons are based on the Nmin content in the useable soil layer. However, for spinach, information from the literature differs for both depth of useable
soil layer and N fertilizer recommendations. The objectives of these experiments were to study the importance of different
soil zones for N supply to spinach and to kohlrabi, and to examine the relationship between N supply in the useable soil layer
and yield of spinach.
Field experiments with both crops showed that about 80% of total root length was in the upper 0–15 cm soil layer and less
than 5% below 30 cm. Spinach roots were present in the 15–30 cm layer only during the last 2 weeks before harvest, whereas
kohlrabi roots penetrated this layer already 4 weeks before harvest. Placement of NO3 below 30 cm depth did not influence root distribution. The top layer contributed about 80% to total N uptake for both crops.
The 15–30 cm soil layer can maximally contribute 40–50 kg N ha-1. It is concluded that N fertilizer recommendations for both crops should be based on the Nmin content of the 0–30 cm soil layer.
Maximum yield of spinach (300 dt f.m. ha-1) was obtained at 150 kg N supply ha-1. The nitrate residue was 50 kg N ha-1 at 0–30 cm in this treatment. It is argued that the nitrate residues at harvest could be decreased by delaying the harvest
for a few days, at slightly suboptimal N supply. 相似文献
108.
A. González A. Casares T. R. Sánchez R. Rodríguez 《In vitro cellular & developmental biology. Plant》1991,27(3):125-131
Summary An experimental rooting system was developed to study in vitro adventitious root formation in hazelnut cotyledons. Experiments
involveda) assay of several culture media,b) use of different developmental status of the seeds (germinated and ungerminated),c) cotyledons subjected to various light regimes, andd) different size of cotyledons slices. It was observed that higher rooting was induced in cotyledonary portions of 5- or 7-mm
thickness (250 and 350 mm3, respectively) cultured on half-strength basal medium supplemented with 50 μM indole-3-butyric acid and 5 μM kinetin. Rooting was affected by light and the developmental state of seeds. Preinitiation, initiation, and root manifestation
stages were defined according to specific culture periods and in relation with morphologic and histologic changes. The first
histologic changes (cell division and root primordia induction) were observed after 12 days in culture. At 30 days of culture
in rhizogenic medium root primodia were fully differentiated with well-developed vascular tissues. 相似文献
109.
几种木本植物插穗生根与内源IAA,ABA的关系 总被引:8,自引:0,他引:8
迄今为止,传统的插条繁殖仍是林业和园林工作者获得良种无性系和培育苗木的重要途径。在影响插穗不定根形成内外因素中,植物内源激素水平和生长调节剂应用占有重要地位。已知第一个根原基细胞的分裂依赖于内源生长素或外源的生长调节剂(Hartmann 1983,Haissig 1974),低浓度的ABA(1.26~20μg/ml)能促进 相似文献
110.
Rooting and acclimatization procedures for micropropagated conifers are reviewed, with emphasis on their effects on root quality and plantlet performance in the nursery and field. Major influences on root production include auxin concentration and mode of application, shoot quality, donor age, clone and temperature. The development of a fibrous, well-branched root system has been a problem that may be solved by using rooting substrates that are better-aerated than agar. Further development of the root system may be enhanced by early air-pruning and ectomycorrhizal associations. During acclimatization, high humidity is required for conifers. However, conifers have an advantage over non-coniferous plantlets with respect to water loss because of a better development of the needle cuticles prior to transfer to in vivo conditions. In greenhouse and field comparisons with seedlings, plantlets were similar in survival and growth rate, but root systems were less fibrous. Also, features of early maturation have been observed for plantlets, the cause of which is uncertain. Pertinent research with rooted cuttings and seedlings of conifers has been cited to gain a better understanding of the factors involved in root production and development. 相似文献