共查询到20条相似文献,搜索用时 842 毫秒
1.
The calabrese cultivar Brassica oleracea var. italica cv. GreenComet was used in a study of the effects of exogenous hormoneson the growth and differentiation of seedling organs in vitro.Four types of explants were tested: hypocotyl segments, rootsegments, primary leaf discs and cotyledon discs. These explantswere incubated on media containing factorial combinations ofBAP x IBA, BAP x NAA, KN x IBA and KN x NAA (all at 0, 0.1,10 and 10.0mg l1). Hypocotyls were the most regenerativeexplants; shoot production was favoured by cytokinin: auxinratios greater than one and was decreased by IBA at 10 mg l1when callus was produced. Shoot formation from root explantsoccurred either in the absence of hormones or with low concentrations;no shoot was produced when any hormone was present at 10 mgl1. In contrast, shoot production from primary leaf diseswas favoured by high concentrations of both auxin and cytokininwith the combination of BAP and IBA the most effective. Shootproduction from cotyledon discs was sporadic with no consistentresponse on any auxin/cytokinin combination. After further experimentson the optimization of hormone concentration, the followingcombinations were chosen as allowing reliable regeneration:0.1 mg l1 BAP+0.1mg l1 IBA for hypocotyl segments,0.075 mg l1 KN +0.025 mg l1 IBA for root segments,and 5.0 mg l1 BAP+5.0 mg l1 IBA for leaf discs. Brassica oleracea var. italica, calabrese, tissue culture, seedling, auxin, cytokinin 相似文献
2.
A micropropagation technique was developed for Delphinium malabaricumusing nodes from inflorescence stalks Maximum shoot proliferationwas obtained on Murashige and Skoog's medium supplemented with2-1P (10 mg l1) and inositol (100 mg l1) Fromthe sixth passage onwards, shoots could be multiplied by omissionof inositol and reduction of 2-1P (0.5 mg l1) concentrationBest rooting response was obtained with a 24-h pulse treatmentof shoots with 0.5 mg I1 IBA in the dark, transfer oftreated shoots to hormone-free half-strength MS medium and incubationunder 24-h light. Regenerated plants were established successfullyin the field Cytological examination of root tips of in vitroand control plants showed identical chromosome number (2n =16) Delphinium malabaricum (Huth) Munz, micropropagation, tissue culture, rare plant 相似文献
3.
Callus of sainfoin (Onobrychis viciifolia Scop.) was initiatedfrom stem and root explants which were obtained from seedlingsgrowing in vitro, on Linsmaier Skoog (LS) medium supplementedwith 1 mg l1 2, 4-D and 1 mg l1 BA or only 1 mgl1 BA, and the Vacin and Went medium without hormones.Somatic embryos were formed on LS medium containing 1 m l1BA. Embryos developed into complete plants on filter paper saturatedwith hormone-free LS medium. Onobrychis viciifolia, somatic embryogenesis, callus culture, plant regeneration 相似文献
4.
Plantlets of Limonium estevei Fdez. Casas, an endangered Spanishspecies, were successfully regenerated from nodal segments excisedfrom young seedlings. Initiation of multiple adventitious budswere obtained in MS modified medium plus 1 mg l1 IBAand 0·1 mg l1 BAP. Rooting was achieved by transferof the isolated shoots to fresh MS medium without plant growthregulators. Fully grown plants were established in a pottingmix and are growing well in a greenhouse. Limonium estevei, in vitro multiplication, adventitious regeneration 相似文献
5.
In vitro Propagation of Narcissus 总被引:2,自引:0,他引:2
Adventitious shoots were induced on leaf, scale and stem explantstaken from the basal plate region of flowering-size bulbs onmedia containing 216 mg l1 6-benzylaminopurineand 0·254·0 mg 11 1-naphthal-eneacetic acid (NAA). Only the levels of NAA had a significanteffect on the numbers of shoots produced. When trimmed and splitin half, 6 mm or more diameter in vitro shoots regenerated furtheradventitious shoots which in turn grew in size suitable forsplitting within 16 weeks. The vigour of the first generation of shoots was proportionalto the hormone levels used for their initiation. All shootseventually declined in vigour, senesced and formed dormant bulbils.Split senescent shoots regenerated only a few secondary shootswhich quickly became senescent. A total of 5002000 bulbilscould be obtained from each initial bulb within 18 months. Bulbilsrequired 10 weeks at low temperature before planting to breakdormancy. Histological observations showed that in twin scales and splitshoots, adventitious shoots were regenerated from at least twosuperficial layers of menstematic cells near to the basal plate.This multicellular mode of origin suggests that plants multipliedfrom in vitro adventitious shoots could be as genetically uniformas those from natural vegetative increase. Narcissus, tissue culture, propagation, adventitious shoots, histology 相似文献
6.
Effects of Sucrose Concentration on the Photosynthetic Ability of Rose Shoots In Vitro 总被引:3,自引:0,他引:3
Reducing the concentration of sucrose in the culture mediumover successive subcultures has been tested as a method forincreasing the ability of rose shoots grown in vitro (Rosa cvsIceberg and Peace) to take up CO2. Shoots maintained on constant10, 20 and 40 g I1 sucrose showed decreased levels ofCO2 uptake at higher sucrose concentrations, although cv. Peacegrew least at 10 g l1 and showed correspondingly lowamounts of CO2 uptake compared with 20 and 40 g l1. Bothcultivars died when sucrose was omitted from the medium. Assucrose concentration was reduced in the medium, so CO2 uptakeof shoots initially cultured on 20 and 40 g l1 sucrosewas found to increase, although a concentration of 10 gl 1sucrose seemed to be limiting, below which the growth and chlorophylllevels of shoots declined. Rosa hybrid, rose, shoot culture in vitro, photosynthetic ability, sucrose, infra-red gas analysis 相似文献
7.
Plantlets were successfully regenerated from shoot segmentsof Betula celtiberica excised from young seedlings. Initiationand elongation of multiple shoot-buds were obtained after 20d culture in MS-modified medium plus BAP 0.6 mg l1 followedby 20 d culture in the same medium in the presence of a reducedBAP concentration (0.1 mg l1). Rooting was achieved 7d after having transplanted the isolated shoots to fresh medium,supplemented with IBA (0.2 mg l1). Betula celtiberica, birch, micropropagation, organogenesis 相似文献
8.
The effect of changes in nitrate-nitrogen supply on the absorptionand distribution of copper was examined in grasses grown inflowing solution culture with a maintained concentration ofcopper. Absorption by roots (µg Cu g1 dry root)decreased markedly when nitrogen had been depleted or was maintainedat 0.1 mg l1 N, but there was an immediate increase whennitrogen was maintained at 1.0 or 10.0 mg l1. There werealso large increases in the concentration of copper in the shootsof plants grown with 1.0 and 10.0 mg 11 N. The rootsof plants grown with 0.1 or 1.0 mg 11 N retained similarproportions of uptake, but a lower proportion was retained whenthe plants were grown with 10.0 mg 11. Although a lowerproportion of the copper was associated with cell walls in theplants grown at 10.0 mg 11 N this was the result of alower content of cell walls rather than an effect on copperitself. In a longer-term experiment in conventional solutionculture with a range of nitrogen concentration, the concentrationof copper in shoots was largely determined by shoot growth. Dactylis glomerata, Festuca arundinacea, Lolium perenne, cell walls, copper absorption, copper distribution, flowing solution culture, nitrate-nitrogen 相似文献
9.
Hypocotyl explants of S. melongena showed three types of regenerationthrough callus formation depending on the concentration of NAAin the medium. At 0.8 mg l1, only callus was produced.Lower concentrations resulted in callus, adventitious roots(optimum, 0.016 mg 11 NAA), and adventitious shoots (noNAA). Roots and shoots developed during the early stages ofculture. Higher concentrations of NAA depressed callus growthand stimulated embryoid formation (optimum 8.0 mg 11NAA), Embryoids were identifiable after about 6 weeks as greenspots on the surface of callus: Addition of 6-BA enhanced shootproduction but inhibited both root and embryoid production.Whole plants were obtained from embryogenic callus after transferto NAA free medium. Genotypic differences in response were observed. In general,the potential for embryogenesis was independent of or inverselyrelated to the potential for organogenesis. 相似文献
10.
In Vitro Embryo Culture and Induction of Multiple Shoots in Lychee (Litchi chinensis Sonn.) 总被引:1,自引:0,他引:1
Immature embryos of different sizes and ages from commercialvarieties of lychee (Litchi chinensis Sonn.) were cultured ina range of different media. Embryos as small as 3 mm could becultured using in vitro techniques and subsequently grown intoplants. MS solid medium with 2% sucrose supplemented with 150ml l1 coconut water was most effective in stimulatingthe germination of immature lychee embryos. Embryos of lycheewere treated to induce adventitious buds from embryonic shootsas a means of achieving multiplication. The different varietiesexhibited differences in response, with Bengal embryonic shootsproducing 15 adventitious buds after pretreatment with 100 mgl1 BAP for 3 h. Root formation was achieved in 65% ofadventitious shoots using MS medium supplemented with 0.5 mgl1 NAA and activated charcoal. These plants were successfullydeflasked and grown on in the glasshouse. This technique providesof means of producing some multiple shoots from lychee embryosand has value for multiplication in a breeding program wherea method of micropropagation is unavailable. Litchi chinensis Sonn., lychee, embryo culture, multiple shoots, in vitro 相似文献
11.
Somatic Embryogenesis from Clonal Leaf Tissues of Cassava 总被引:3,自引:0,他引:3
Leaf lobes were isolated from palmate leaves of clonal cassava(Manihot esculenta Crantz) material growing in vitro or in glasshouseconditions and subjected to a two-stage culture procedure involvingincubation on Murashige and Skoog (MS2) basal medium supplementedwith 212 mg l1 2,4-D for 20 d (Stage I) beforetransfer to MS2 basal medium supplemented with 0.01 mg l12,4-D and 0.1 mg l1 6-benzylamino purine (BAP) (StageII medium). Embryogenetic tissues, foliose structures and somatic embryosdeveloped from leaf lobes at all Stage I 2,4-D concentrations,except on those explants isolated from shoot-tip cultures incubatedon MS2 basal medium supplemented with 0.1 mg l1 NAA and1.0 mg l1 BAP. Leaf lobes isolated directly from glasshouse plants showed optimalembryogenetic competence when subjected to a Stage I cultureperiod of 17 d, although foliose structure initiation was optimalwith shorter Stage I durations. Leaf lobes of 24 mm lengthand those isolated from phyllotaxic leaf numbers 4 and 5 showedthe greatest embryogenetic competence. Manihot esculenta, cassava, somatic embryogenesis, tissue culture, morphogenetic competence 相似文献
12.
Somatic embryogenesis can be induced in tissue cultures of Freesiarefracta either directly from the epidermal cells of explants,or indirectly via intervening callus. These two pathways ofsomatic embryogenesis can be controlled and regulated by varyingthe combinations and levels of exogenous hormones. When younginflorescence segments were cultured in vitro on modified N4(MN4) medium supplemented with 2 mg l1 indoleacetic acid(IAA) and 3 mg l1 6-benzylaminopurine (BAP), some ofthe epidermal cells began to exhibit the features of embryogeniccells. These cells produced embryoids and developed into newplants through direct somatic embryogenesis. If the same explantswere placed on Murashige and Skoog's (MS) medium containing2 mg l1 IAA, 05 mg l1 BAP and 05 mg l1naphthaleneacetic acid (NAA), pale-yellow translucent nodularcalluses appeared on the surface of the explants. When thiskind of callus was transferred to MN6 medium with 2 mg l1IAA and 3 mg l1 BAP, embryoids formed which further developedinto plantlets. The regenerated plants were morphologicallynormal and possessed the normal diploid chromosome number of2n = 22. A similar result has also been obtained with youngleaf explants of this plant. The early segmentations of embryogeniccells and the development of embryoids were studied using histologicaland scanning electron microscopic techniques, and the resultshave been discussed in association with the ontogeny and originof the embryoids. Freesia refracta Klatt, somatic embryogenesis, plant regeneration, exogenous hormones 相似文献
13.
Bulbil development in cultured nodes of D. bulbifera proceededin the absence of growth substances from the medium. When IAAwas incorporated into the medium at the concentrations of 5mg l1 and 10 mg l1 the cultured nodes producedlarger bulbils than in its absences. When the concentrationof IAA was increased to 15 mg l1, however, the culturednodes produced a callus instead of a properly organized bulbil.The dry weight of bulbils increased when kinetin was added tothe medium at the concentrations of 0.05, 0.5, and 2.5 mg l1.The greatest increase was with 0.5 mg l1 kinetin. Onincreasing the concentration of kinetin in the medium to 5.0mg l1 the tissue produced had smaller dry weight thanthose produced in the absence of growth substances. Additionof different combinations of IAA and kinetin to the basal mediumresulted in the production of normal bulbils, roots, and shootsin some instances (suitable combinations) and in the productionof callus and abnormal shoots in others (non suitable combinations). 相似文献
14.
Multiple shoots were induced on excised hypocotyl segments andshoot tips of in vitro germinated seedlings of Indian rosewood(Dalbergia latifolia) on Murashige and Skoog's medium supplementedwith cytokinins and auxins. Roots were induced when individualshoots were treated first with half strength MS medium supplementedwith NAA, IAA and IBA (1 mg 11 each) and subsequentlytransferred to hormone-free half-strength MS medium. The plantletswere then transferred to pots and grown in the greenhouse. Dalbergia latifolia, micropropagation, tissue culture, clonal propagation 相似文献
15.
Multiple shoots were induced from nodal segments of seedlingsof Syzygium aromaticum, on Murashige and Skoog's (MS) basalmedium at half strength salts and Gamborg's medium (B5), supplementedwith BAP and NAA. Six to eight shoots were obtained when 3 mgl1 BAP and 0.5 mg l1 NAA were used in the medium.Both MS medium and B5 medium showed more or less similar resultsregarding the proliferation of the explants. Syzygium aromaticum (L) Merr and Perry (clove), multiple shoots, regeneration 相似文献
16.
By manipulation of various growth regulators and physical conditions,plants have been regenerated from excised roots, stem segments,cotyledons, leaves, and callus cultures of red cabbage (Brassicaoleracea var. capitata) grown under in vitro conditions. Shootbuds were induced on isolated root segments (1 cm long) culturedon Murashige and Skoog's medium and the frequency of bud formationwas greatly enhanced by the addition of kinetin (0.5 part 106).Callus obtained from the seeds, cotyledons, and hypocotyl segmentscultured on a medium fortified with 2,4-D (1 part 106),kinetin (0.1 part 106), and coconut milk (10%, v/v) hasbeen repeatedly subcultured. The callus is slow growing, andon transference to a kinetin (2 parts 106) and IAA (2parts 106) medium underwent morphogenesis to give riseto plants. The significance of the propagation of red cabbageby in vitro culture is pointed out. 相似文献
17.
Agrobacterium rhizogenes Mediated Transformation of the Forage Legumes Medicago sativa and Onobrychis viciifolia 总被引:3,自引:0,他引:3
GOLDS T. J.; LEE J. Y.; HUSNAIN T.; GHOSE T. K.; DAVEY M. R. 《Journal of experimental botany》1991,42(9):1147-1157
Three cultivars of M. sativa and one cultivar of O. viciifoliawere evaluated for their response to inoculation with A. rhizogenesstrain A4T (containing pRiA4b). A cultivar-dependent responsewas observed in M. sativa with 94%, 25%, and 4% of infectedstem explants producing transformed roots in the cultivars Vertus,Regen-S, and Rangelander, respectively. In O. viciifolia cv.Hampshire Giant, an explant-dependent response was observedwith 78% and 50% of seedling cotyledon and hypocotyl explantsresponding, respectively. Leaf explants failed to produce transformedroots. Transformed roots showed plagiotropic and negativelygeotropic growth on hormone-free agar MS medium. Productionof transgenic shoots from O. viciifolia root cultures occurredspontaneously. Recovery of transgenic plants from M. salivacv. Rangelander was achieved by transfer of callus (inducedon UM medium containing 2·0mg dm3 2,4-D and 0·25mg dm3 kinetin) to MS medium containing 0·5 ingdm3 BAP and 0·05 mg dm3 NAA. Cultured rootsof both species synthesized opines (agropine and mannopine).Extensive morphological variation was observed in plants ofM. sativa (clone Al) and O. viciifolia (clone A4Tl) establishedin the glasshouse. DNA sequences homologous to TL-DNA and TR-DNAwere present in root clones and regenerated plants. Key words: Agrobacterium rhizogenes, Medicago sativa, Onobrychis viciifolia, transformed roots, transgenic plants 相似文献
18.
Effects of a Range of O2 Concentrations on Porosity of Barley Roots and on their Sugar and Protein Concentrations 总被引:1,自引:0,他引:1
Barley was grown at a range of oxygen concentrations (0.59mg l1), in nutrient solutions. Growth of both shootsand seminal roots was restricted by O2 concentrations lowerthan 23 mg l1) but nodal root growth was not. Root porosities were increased even at those O2 concentrationswhich did not restrict growth, and were inversely proportionalto the protein levels of the roots. Sugar concentrations increasedappreciably only at those O2 concentrations which also restrictedgrowth. Hordeum vulgare L., barley, root porosity, sugar, protein, oxygen concentration 相似文献
19.
The efficiency of an avocado hybridization programme, usingsmall potted glasshouse plants, was reduced by a high rate ofabscission of immature fruitlets bearing embryos too young forconventional germination. This was overcome in part by culturein vitro of the shed embryos on a liquid medium supplementedwith 0.5 mg l1 benzyladenine. Most embryos younger than6 weeks did not survive in culture, but older embryos slowlyproduced multiple shoots, with axillary shoot growth being furtherstimulated by removal of both cotyledons. Embryo response wasnot related to cultivar. Shoots removed from culture could begrafted to seedling rootstocks. Grafting was considered morereliable than dependence on growth of the main root or adventitiousroots in vitro to produce established plants. Persea americana Miller, avocado, abscissed fruitlets, in vitro embryo culture 相似文献
20.
Direct Organogenesis from Petiole and Thin Cell Layer Explants in Sugar Beet Cultured In Vitro 总被引:1,自引:0,他引:1
DETREZ C.; TETU T.; SANGWAN R. S.; SANGWAN-NORREEL B. S. 《Journal of experimental botany》1988,39(7):917-926
Detrez, C., Tetu, T., Sangwan, R. S. and Sangwan-Norreel, B.S., 1988. Direct organogenesis from petiole and thin cell layerexplants in sugar beet cultured in vitro.J. exp. Bot.39: 917926. Plant regeneration was obtained by direct bud formation frompetiole as well as from thin cell layer explants taken fromsugar beet (Beta vulgaris L.) plants grown in vitro. The budswere mainly induced in the blade-petiole transition zone ofthe explants. High frequency bud regeneration was observed inpetiole and thin layer explants of 10 different breeding linesof sugar beet tested. Organogenesis resulted when petiole explantsexcised from 8-d-old seedlings grown on half-strength Murashigeand Skoog medium (MS) containing 3.0 mg dm3 naphthaleneacetic acid (NAA), 3.0 mg dm3 6-benzylaminopurine (BAP)and 1.0 mg dm3 2, 3, 5, triiodobenzoic acid (TIBA) werecultured on MS with 3.0 mg dm3 NAA and 3.0 mg dm3BAP. Thin cell layer strips isolated from shoot apices culturedon MS medium supplemented with 09 mg dm3 BAP or1.0 mg dm3 indolebutyric acid (IBA) formed adventitiousbuds on MS medium containing 05 mg dm3 NAA + 5.0mg dm3 BAP. Histological studies confirmed the sub-epidermalorigin of shoots. Key words: Beta vulgaris, direct organogenesis, in vitro culture, petiole, regeneration, thin cell layer 相似文献