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排序方式: 共有224条查询结果,搜索用时 15 毫秒
1.
Trevor J. Douglas Victor M. Villalobos Michael R. Thompson Trevor A. Thorpe 《Physiologia plantarum》1982,55(4):470-477
Cotyledon explants of radiata pine contain principally lipid and protein reserve materials, which decline during shoot initiation. This process was followed phytochemically and ultrastructurally. Fatty acid and sterol analyses indicated that there were both quantitative and qualitative changes in the different classes of lipid. The most pronounced changes were an increase in the linolenic acid content of the polar lipids and the appearance of stigmasterol during shoot initiation. There was also a continued increase in chlorophyll and carotenoid levels, which paralleled chloroplast development. It appears that the changes observed were similar to those that occur in cotyledons during normal seedling development. 相似文献
2.
Daxu Li Jie Zhang Jian Zhao Yi Zhang Fei Chen Jingqiu Zhu Shujun Liu Zhirong Yang 《Plant Cell, Tissue and Organ Culture》2006,84(3):285-292
The mature seeds, mesocotyls, and young leaf tips of Elymus sibiricus L. cv. ‘chuancao No. 2’ were cultured on Murashige and Skoog (MS) medium supplemented with 5.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-d) and 0.05 mg/L kinetin in the dark at 26°C, the calluses were produced. The rate of callus regeneration depended on the explants
source and plant growth regulators. Plants regenerated from whitish-yellow-coloured compact nodular callus formed after subculturing
for 8 weeks. Higher frequency (54%) of shoot differentiation was obtained from the embryo tissues of mature seed than from
either mesocotyls (24%) or young leaf tip tissues (6%) when these calluses from different types of explants were cultured
on plant regeneration medium containing half strength MS salts supplemented with 0.1 mg/L kinetin, 1.5 mg/L 2,4-D and 20 g/L sucrose. The green plants were rooted within 6 weeks in the root regeneration medium, and over 97% of these soil-established
plants were obtained in the greenhouse when potted in a sand and peat mixture medium. 相似文献
3.
The effect of sucrose on fruiting, seed production, and seed germination of lesser centaury [Centaurium pulchellum (Sw.) Druce] was examined using explants of flowers and flower buds. Sucrose concentrations in the culture medium ranged
from 0.003 to 0.3 M. It has been shown that the number of auxiliary buds, capsules dimension, number of viable seeds per capsule
and seed dimensions increased with the increase of sucrose concentrations. The highest values were recorded at sucrose concentrations
higher than 0.03 M, except for seeds size, which were larger at sucrose concentration ranging from 0.003 to 0.1 M. The germination
of in vitro produced seeds was affected by previous culture history: a higher germination percentage was obtained in seeds that were
raised from explants originally grown on medium with sucrose concentrations higher than 0.003 M. 相似文献
4.
濒危植物盐桦离体组织培养特性的研究 总被引:1,自引:1,他引:0
目的:探讨新疆濒危植物盐桦离体组织培养的特性。方法:从盐桦原生地阿尔泰阿拉哈克盐湖边采摘盐桦休眠实生苗上的落叶枝条,待其萌发后分别取带芽嫩茎、嫩茎茎段及嫩叶芽尖三种不同材料接种于启动培养基,比较三种盐桦离体组织的诱导分化,继而设计不同激素、不同水平的单因子试验和正交试验,筛选适宜盐桦外植体芽增殖和生根的分化培养基。结果:诱导盐桦芽增殖的最佳外植体是带芽嫩茎,盐桦外植体增殖、壮苗最适培养基为:MS 6-BA 1.0mg/L IBA 0.5mg/L;盐桦外植体生根最适培养基为:1/2MS IBA 0.5mg/L 蔗糖30g/L 琼脂7% 暗光处理3d。结论:本研究筛选获得适宜盐桦芽增殖和生根的最佳培养条件,为高效扩繁和保存盐桦种质资源奠定了基础。 相似文献
5.
辣椒离体培养及再生体系的研究 总被引:8,自引:0,他引:8
选用9个辣椒(Capsicum annuumL.)品种(系),研究了不同激素组合、基因型、外植体类型、苗龄和Ag-NO3等因素对外植体不定芽分化和伸长的影响.结果表明,在6-BA/IAA为10∶1配比下,有利于辣椒外植体的分化再生,而6-BA/IAA为3∶1配比下适合于再生芽的伸长;不同品种辣椒的再生能力差别较大,分化率在13.3%~90.0%之间;辣椒子叶再生能力比下胚轴强,是较好的外植体材料;12~16 d苗龄的外植体分化频率较高;添加4mg?L-1AgNO3可使芽分化率平均提高16.9%.通过比较,筛选出了适合于辣椒芽分化的培养基为MB5(MS无机盐 B5有机成分) 5 mg?L-16-BA 0.5 mg?L-1IAA 4 mg?L-1AgNO3,芽伸长培养基为MB5 3 mg?L-16-BA 1 mg?L-1IAA 2 mg?L-1GA3 4 mg?L-1AgNO3,生根培养基为1/2 MS 0.2 mg?L-1IAA 0.1 mg?L-1NAA. 相似文献
6.
《Cell cycle (Georgetown, Tex.)》2013,12(15):2765-2766
Comment on: Tran KV, et al. Cell Metab 2012; 15:222-9. 相似文献
7.
Karl-Frederik Bergeron Tatiana Cardinal Nicolas Pilon 《Journal of visualized experiments : JoVE》2013,(79)
Neural crest cells (NCC) are a transient and multipotent cell population that originates from the dorsal neural tube and migrates extensively throughout the developing vertebrate embryo. In addition to providing peripheral glia and neurons, NCC generate melanocytes as well as most of the cranio-facial skeleton. NCC migration and differentiation is controlled by a combination of their axial origin along the neural tube and their exposure to regionally distinct extracellular cues. Such contribution of extracellular ligands is especially evident during the formation of the enteric nervous system (ENS), a complex interconnected network of neural ganglia that locally controls (among other things) gut muscle movement and intestinal motility. Most of the ENS is derived from a small initial pool of NCC that undertake a long journey in order to colonize - in a rostral to caudal fashion - the entire length of the prospective gut. Among several signaling pathways known to influence enteric NCC colonization, GDNF/RET signaling is recognized as the most important. Indeed, spatiotemporally controlled secretion of the RET ligand GDNF by the gut mesenchyme is chiefly responsible for the attraction and guidance of RET-expressing enteric NCC to and within the embryonic gut. Here, we describe an ex vivo cell migration assay, making use of a transgenic mouse line possessing fluorescently labeled NCC, which allows precise quantification of enteric NCC migration potential in the presence of various growth factors, including GDNF. 相似文献
8.
Vinod Kumar Ashwani Sharma Bellur Chayapathy Narasimha Prasad Harishchandra Bhaskar Gururaj Parvatam Giridhar Gokare Aswathanarayana Ravishankar 《Acta Physiologiae Plantarum》2007,29(1):11-18
Direct shoot bud induction and plant regeneration was achieved in Capsicum frutescens var. KTOC. Aseptically grown seedling explants devoid of roots, apical meristem and cotyledons were inoculated in an inverted
position in medium comprising of Murashige and Skoog (Physiol Plant 15:472–497, 1962) basal medium supplemented with 2-(N-morpholine) ethanesulphonic acid buffer along with 2.28 μM indole-3-acetic acid, 10 μM silver nitrate and either of 13.31–89.77 μM
benzyl adenine (BA), 9.29–23.23 μM kinetin, 0.91–9.12 μM zeatin, 2.46–9.84 μM 2-isopentenyl adenine. Profuse shoot bud induction
was observed only in explants grown on a media supplemented with BA (26.63 μM) as a cytokinin source and 19.4 ± 4.2 shoot
buds per explant was obtained in inverted mode under continuous light. Incorporation of polyamine inhibitors in the culture
medium completely inhibited shoothoot bud induction. Incorporation of exogenous polyamines improved the induction of shoot
buds under 24 h photoperiod. These buds were elongated in MS medium containing 2.8 μM gibberellic acid. Transfer of these
shoots to hormone-free MS medium resulted in rooting and rooted plants were transferred to fields. This protocol can be efficiently
used for mass propagation and presumably also for regeneration of genetically transformed C. frutescens. 相似文献
9.
I. Sivanesan Byoung Ryong Jeong 《In vitro cellular & developmental biology. Plant》2007,43(5):436-441
A method was developed to initiate multiple shoots from mature nodal explants of Sida cordifolia Linn. High frequency of regeneration was achieved on Murashige and Skoog (MS) medium supplemented with 2.0 mg l−1 6-benzylaminopurine, 0.5 mg l−1 α-naphthalene acidic acid, 1.0 mg l−1 adenine sulfate, and 10% (v/v) coconut milk. Multiple shoots were initiated within 21 d and the above media was capable of inducing the formation of more
than 20 shoots from each explant. Regenerated shoots were successfully rooted on half-strength MS medium supplemented with
2.0 mg l−1 indole-3-butyric acid and 3% (w/v) sucrose. Rooted plantlets were established in soil. The regenerated plantlets showed no morphological differences from the
parent material. This protocol could be useful for germplasm conservation, cultivation, and genetic improvement of S. cordifolia. 相似文献
10.
A study was conducted to evaluate in vitro techniques for germplasm preservation of wild species of Arachis. Nodal segments excised from in vitro-grown plants of A. retusa, A. macedoi and A. burchellii were used to examine the effects of explant position and age of the donor plant. Explants were excised from plants maintained in culture for 30, 60, 90 or 180 d, numbered I – V from top to bottom and cultured on MS medium supplemented with 2.7 µM NAA or different BAP concentrations (0, 4.4, 13.2 and 22 µM). The age of the donor plant has not influenced the responses of the four genotypes studied. In contrast, shoot regeneration ability was significantly affected by the original explant position, decreasing from top to bottom. In media supplemented with different BAP concentrations, multishoot formation was induced from apical segments at low frequencies (10 – 20%) and segments of all positions originated calluses at the explant basis after 30 d of culture. The culture of nodal segments in the presence of 2.7 µM NAA as the sole growth regulator is recommended for the multiplication of in vitro collections of wild groundnut species in order to avoid callusing and adventitious shoot formation. 相似文献