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111.
Wayne A. Mackay 《In vitro cellular & developmental biology. Plant》1999,35(4):283-284
Summary There are many Chihuahuan desert species that have potential as landscape plants for the arid communities of the southwestern
United States [agarita, Berberis trifoliata Moric.; Mexican buckeye, Ungnadia speciosa Endl.; Texas madrone, Arbutus xalapensis var. texana (Buckl.). A. Gray]. Within these plant populations, there are superior genotypes that offer even greater interest for the
landscape. However, it is difficult to clonally propagate many of these species with conventional techniques, and the seed-derived
populations often do not breed true. Therefore, selection of superior genotypes in wild populations coupled with clonal propagation
through tissue culture may offer an attractive option. It is relatively easy to achieve disinfestation of explants from desert
plants due to a general lack of natural surface contamination by fungi and bacteria, even though interference from numerous
trichomes can impede good contact with disinfesting agents. However, there is only a narrow window of time that is ideal for
explant collection, because of the brief, periodic flushes of growth that characterize this unusual plant group. There may
be years when, due to the harsh environment, the amount of suitable explant material is severely limited. Phenolics and exudates
are also problematic in this group of plants, and acclimatization of ex vitro plantlets to the harsh desert environment is
a particular challenge. For these reasons, specific adaptations and modifications were necessary to achieve success with micropropagation
of desert plant species such as Mexican redbud (Cercis canadensis var. mexicana L.). 相似文献
112.
Roberta H. Smith Jody Burrows Kristen Kurten 《In vitro cellular & developmental biology. Plant》1999,35(4):281-282
Summary Conventional propagation of amaryllis, Hippeastrum Herbert sp. hybrids by bulb offsets is slow, seasonal, and variable; additionally, some amaryllis hybrids do not produce
many offsets. From seed, it takes approximately 2 yr to flower. Micropropagation of Zephyranthes L. sp. bulbs has challenges related to contamination of stage I cultures as well as genotype differences in culture media
requirements. There are literature reports on in vitro propagation of both genera; however, the application of these reports
to new cultivars leaves unanswered questions regarding surface disinfestation, explant, nutrient media, and multiplication
rates. Surface disinfestation of container-grown Hippeastrum spp. hybrid cv. San Antonio Rose bulbs resulted in contamination rates of 20 to 100% in spite of various treatments, some
of which killed the explant. Twin scale explants of San Antonio Rose bulbs responded on a Murashige and Skoog salt medium
with 2 mg naphthalene acetic acid per 1, and transfer to soil was not a problem. In contrast, aseptically germinated seed
of Zephyranthes sp. served as a suitable source of clean bulb tissue. 相似文献
113.
114.
Somatic embryos differentiated from hypocotyl explant in cotton (Gossypium hirsutum L.) exhibited very divergent morphologies. Six different types of somatic embryos based on cotyledon development were observed.
The growth hormones (2,4-dichlorophenoxyacetic acid and kinetin) used in induction and maintenance media did not affect embryo
rooting and germination. The 95 % conversion of normal embryos (with two cotyledons) was achieved, while an overall conversion
was only 38 %. Horn shaped embryos failed to exhibit shoot growth. Poorly developed apical meristems were responsible for
lower conversion percentages in some of embryo classes. However, regenerated plants phenotypically resembled to seed grown
control plants regardless of somatic embryo morphology. 相似文献
115.
Negash Almaz Puite Klaas Schaart Jan Visser Bert Krens Frans 《Plant Cell, Tissue and Organ Culture》2000,62(2):153-158
Three clones of enset (Ensete ventricosum Welw. Cheesman) from southwestern Ethiopia (Keffa-Shaka zone) were investigated for their potential for micropropagation
and regeneration in tissue culture. Corm and leaf tissue of greenhouse-grown plants as well as in vitro germinated zygotic embryos were used as starting material for micro-propagation and regeneration studies. Embryos were excised
from disinfected seeds and cultured in vitro. Multiple shoots from both corm- and embryo-explants were obtained using regeneration medium supplemented with 10 μM or 20
μM BAP. Rooting of shoots was achieved using medium with 5 μM IBA, 1 μM BAP and 1 g l−1 activated charcoal. Plantlets obtained by this process were transferred to soil under greenhouse conditions. Optimal conditions,
which were determined for clonal propagation of three different genotypes of enset, allowing both in vitro micropropagation and regeneration, are described. This protocol makes for conservation of enset clones, rapid propagation
of selected disease-free germplasm and more efficient breeding procedures.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
116.
The aim was to produce a tetraploid form of Buddleia globosa to facilitate introgression of yellow flower colour into B. davidii, which is naturally tetraploid. Protocols were established for the micropropagation of B. globosa and tetraploid plants were obtained by application in vitro of colchicine to pre-cultured excised nodal sections. Three concentrations of colchicine were applied (0.01%, 0.05% and 0.1%
w/v) for 1, 2 or 3 days. At 0.01% tetraploids were produced only after 2 days of application. All other treatments produced
at least one tetraploid. The colchicine technique was extremely effective: of 29 lines tested, 19 were tetraploid and 5 were
mixoploid. The vegetative characteristics of these tetraploids are described and the flowering characteristics of the three
that flowered.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
117.
Anatomy of normal and hyperhydric leaves and shoots of in vitro grown Simmondsia chinesis (link) schn 总被引:1,自引:0,他引:1
Nancy M. Apóstolo Berta E. Llorente 《In vitro cellular & developmental biology. Plant》2000,36(4):243-249
Summary The anatomy of normal and hyperhydric in vitro shoots and leaves from micropropagated simmondsia chinensis (Link.) Schn. (jojoba) was compared with that of seedlings (control plants). In vitro normal plantlets displayed good development and survived during the acclimatization stage. In vitro hyperhydric plantlets presented numerous anatomical defects, such as hypertrophy of the mesophyll and of the stem cortex,
malformed non-functional stomata, epidermal discontinuity, and xylem hypolignification; they did not survice acclimatization.
The study of the anatomical features of in vitro jojoba shoots and leaves allowed determination of the structural condition of the plantlets and prediction of which plantlet
would survive the critical acclimatization stage. 相似文献
118.
Ajith Anand Chaluvadi Srinivasa Rao 《In vitro cellular & developmental biology. Plant》2000,36(1):61-64
Summary A protocol is described for rapid multiplication of Piper barberi Gamble (Piperaceae) through shoot tip and nodal explant cultures. Nodal explants with a single axillary meristem showed three
times better response with respect to shoot proliferation when compared to shoot tip explants. The best shoot proliferation
response of nodal explants was observed with a cytokinin combination of N6-benzyladenine (4.43 μM) and kinetin (2.32 μM), with 88% bud break. The number of shoot initials (2.4) produced per nodal explant was twice the number of shoot initials
(1.2) per shoot tip. An average of 6.9±0.58 adventitious shoots were observed from the proximal end of the internodal explants
on Mursashige and Skoog (1962) (Ms) basal medium supplemented with N6-benzyladenine (2.22 μM) and kinetin (0.46 μM). A multiplication rate of 82 shoots per explant could be achieved after 9 wk of subculturing. The in vitro shoots were rooted on one-half and one-quarter MS basal medium. The shoots rooted on one-quarter MS in the dark produced
eight roots with an average root length of 3.36 cm and 98% survival. These plants were transferred to the field with a survival
rate of 75%. 相似文献
119.
阳春砂仁微繁殖技术研究 总被引:1,自引:0,他引:1
以阳春砂仁的芽块为外植体,在附加1~6mg/L 6-BA的MS培养基上,可实现丛生芽增殖。最佳启动和增殖培养基为MS+5mg/L BA+5ml/L 20%硫代硫酸钠,出苗率和增殖率分别为62.5%和5.36。采用1/2 MS+1mg/L IBA+0.5mg/L IAA进行离体生根,生根率可达94.6%。 相似文献
120.
An efficient protocol has been developed for rapid in vitro propagation of Eclipta alba L. (Asteraceae) through axillary bud multiplication. Murashige and Skoog (MS) medium supplemented with BA (10 M) was found
to be most effective in breaking bud dormancy. An average number of 23 ± 0.57 shoots per explant was recorded after 30 days.
Culture of node segments on fresh medium with lower concentration of BA (2 M) enhanced the multiplication rate. A maximum
of 79 ± 1.90 mean number of shoots were obtained after three subcultures without any decline in multiplication rate. The regenerated
microshoots showed the most efficient rooting on half strength MS medium augmented with 0.5 M IBA. Plantlets went through
a hardening phase prior to ex vitro transfer and established in earthen pots containing garden soil; survival of about 90%. The established plants were uniform
and exhibited morphological characters identical to mother plants. 相似文献