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11.
Relation between electrokinetic potentials and growth in callus cultures ofTrigonella foenum-graecum
Callus cultures ofTrigonella foenum-graecum were initiated from radicle or cotyledon portions of seedlings and young leaves and maintained on modified 1-B5 medium. The
callus mass was disaggregated by mechanical agitation and the discrete cells thus obtained were used to measure their electrokinetic
potential. Studies pertaining to the effects of ageing on electrokinetic potential and growth index revealed a relationship
between these two parameters. Thus, the rate of change of electrokinotie potential with age could be employed as a parameter
to study the growth kinetics of cells in callus cultures. 相似文献
12.
Calli of P. argentatum were grown on a newly designed liquid nutrient flow-through system which facilitated the subculturing of calli and delayed
browning for 6 weeks. Friable calli were obtained on half-strength Gamborg B5-medium supplemented with 0.05 mgl−1 2,4-dichlorophenoxyacetic acid. Shoots developed on media supplemented with 0.2 mgl−1 benzylaminopurine but lacking 2,4-dichlorophenocyacetic acid. 相似文献
13.
Studies were performed to define tissue culture techniques and culture conditions for morphogenesis, callus culture and plantlet culture of sweet orange (Citrus sinensis (L.) Osb.), citron (C. medica L.) and lime (C. aurantifolia) (Christm. Swing). The optimal concentrations of NAA to induce root formation on stem segments were 10 mg l-1 for sweet orange and lime, and 3 mg l-1 for citron. The optimal BA concentration for shoot and bud proliferation was 3 mg l-1 for sweet orange and citron, and 1 mg l-1 for lime. Callus initiation was accomplished in a culture medium containing 10 mg l-1 NAA and 0.25 mg l-1 BA. Callus was maintained by periodical subculture into the same medium supplemented with 10% (v:v) organge juice. In vitro plantlets of the three species were obtained by rooting of shoots developed from bud cultures, and of citron and lime by development of shoots from root cultures. The plants were successfully established on soil. 相似文献
14.
Calli from hypocotyl and root explants of Digitalis obscura L. showed regeneration of adventitious shoots, roots and embryos when transferred to Murashige & Skoog medium supplemented with cytokinins alone or in combination with auxins. Optimum shoot-bud formation was achieved in the presence of IAA and BA, while roots mainly appeared either in absence of growth regulators or with IAA and Kn. Embryo formation took place only in those combinations that included Kn. Embryo development was influenced by the type of auxin, and precocious germination occurred in media with NAA. Mechanically isolated cells from hypocotyl- and root-derived calli were plated in MS medium supplemented with several IAA and BA combinations. Single cells were able to proliferate forming callus within 20–30 days in culture. In order to induce organogenesis, calli were transferred to various regeneration media. Shoot-bud differentiation efficiency depended on both callus origin and medium initially used for cell culture, best results being obtained in calli grown from hypocotyl-derived cells cultured in the presence of casein hydrolysate. A further subculture to medium containing coconut milk and lower concentrations of NH4NO3 and sucrose promoted shoot development. Rooting was readily achieved upon transferring shoots onto half-strength MS medium. Plantlets were ultimately established in soil.Abbreviations BA
benzyladenine
- BM
basal medium
- CH
casein hydrolysate
- CM
coconut milk
- 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
indoleacetic acid
- Kn
kinetin
- MS
Murashige & Skoog
- NAA
naphthaleneacetic acid 相似文献
15.
Dragan V. Vinterhalter 《Plant Cell, Tissue and Organ Culture》1989,17(1):13-19
Callus tissue was induced in young stem segments cultured on MS based media supplemented with 0.25–0.5 mg l-1 2, 4-D. Shoots were differentiated on media containing 0.5–1.0 mg l-1 BA and 0.5–2.0 mg l-1 IBA or 0.1–0.2 mg l-1 NAA. The same media were suitable for shoot multiplication. Shoot elongation and rooting were strongly inhibited by BA and stimulated by auxins IBA and NAA. Medium containing 0.5 mg l-1 IBA was optimal for rooting. Root elongation was stimulated by light and inhibited in darkness. Transfer of rooted plantlets to outdoor conditions was feasible and special hardening procedures were not required. Among more than 5000 plants produced by this procedure only 9 off-type plants with variegated leaves were found. 相似文献
16.
The experiment was conducted to investigate the human thermoregulatory responses during rest, exercise and recovery atT
a 20°C and 60% R.H. under the conditions of wearing two different types of clothing. Six healthy men wore two types of clothing: one covering the whole body area except the head (Type A, weight 1656 g), and the other covering only the trunk, upper arms and thighs (Type B, weight 996 g). The level of rectal temperature was kept significantly higher in Type B than in Type A during rest and recovery. The increased and decreased rates of rectal temperature during exercise and recovery were significantly greater in Type A than in Type B, respectively. These findings are discussed from the viewpoint of the differences of skin temperatures of the extremities between Type A and Type B. 相似文献
17.
Summary Axillary bud expiants from South Pacific (Solomon Islands) taro, Colocasia esculenta var. esculenta cv. Akalomamale (Araceae) cultured on a modified Murashige-Skoog medium containing 1 mg NAA 1–1 and TE formed callus and produced multiple plantlets. Explants died if NAA was present at levels lower than 0.1 mg 1–1. BA was not required and may have been inhibitory. Plantlets developed faster and became larger following transfer to a hormone-free medium two weeks after the start of culture. Fully grown plants were established in a potting mix and are growing well in a greenhouse.Abbreviations BA
benzyladenine
- BM
basal medium
- Ca
Colocasia esculenta var. antiquorum
- Ce
Colocasia esculenta var. esculenta
- Ck
cytokinin(s)
- CW
coconut water
- HSMSM
half strength Murashige Skoog macroelements
- HSMS
half strength Murashige and Skoog medium
- IM
initial medium(ia)
- MS
Murashige and Skoog medium
- NAA
naphthaleneacetic acid
- SM
second medium
- TE
taro corm extract
- UCI
University of California, Irvine 相似文献
18.
Calluses induced fromPterocladia capillacea have been kept in culture for more than three years. They exhibit a fast growth rate, owing to the release of single cells, which in turn develop into new callus. The effect of various media and culture conditions upon growth was investigated. In order to confirm the identity of the callus cells, a 0,45 mg incoculum was grown that yielded 15 g dried callus within six weeks. Polysaccharides from this material (5.5 g) were analysed by13C NMR spectroscopy. This produced a spectrum typical of agar and very similar to the one obtained for agar extracted fromP. capillacea plants. However, the callus agar displayed no gel-forming properties, even after alkali modification.author for correspondence 相似文献
19.
小麦—天兰偃麦草—黑麦三属杂种花粉植株诱导条件的研究 总被引:3,自引:1,他引:2
研究表明,三属杂种处于单核中晚期阶段的花粉最适于诱导形成愈伤组织。低温预处理对促进三属杂种花粉愈伤组织的诱导有一定的作用。利用以马铃薯提取物为基础物质的马铃薯-Ⅱ培养基作诱导培养基,其愈伤组织诱导与分化的频率比目前两个较好的合成培养基要高。同一个三属杂种F_1春、秋播种植株之间在形成愈伤组织的能力上有较大的差异,秋播材料形成愈伤组织的能力明显高于春播材料。F_(?)杂种植株诱导愈伤组织和分化植株的频率均比F_1杂种明显提高。 相似文献
20.
A non-sporulating isolate of Alternaria brassicae, inoculated on callus culture of Brassica juncea cv. Kranti, colonized the callus and produced spores. When captafol, a fungicide, was added (100 mg/l) to the callus culture medium, if effectively checked fungal contamination and saprophytic growth of A. brassicae on culture medium, without adversely affecting callus growth or establishment of dual culture. 相似文献