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81.
Explants from leaves of in vitro-grown chrysanthemum (Dendranthema grandiflora Tzvel.) cultivars regenerated adventitious shoots without an intermediate callus phase. Puncturing explants with a brush increased regenerations, but in combination with cocultivation with Agrobacterium tumefaciens it had an adverse effect on shoot formation. The negative effect of brushing and cocultivation could be overcome by preculturing explants for 8 days. Preculture altered the location of transformed sites but did not inhibit transformation. Regeneration following cocultivation with Agrobacterium is also encouraged if alternative regeneration protocols are used that do not require brushing.Abbreviations BA benzyladenine - GUS -glucuronidase - IAA indoleacetic acid - NAA naphthaleneacetic acid  相似文献   
82.
In an attempt to develop a system for producing transformed plants from explants ofDendranthema grandiflora, the susceptibility of the cultivar Super White to various wild-type strains ofAgrobacterium tumefaciens andA. rhizogenes was investigated. Tumour formation was not a reliable indicator of the ability of a related disarmed strain to mediate transformation. Following inoculation of explants with disarmedAgrobacterium strains, a number of shoots developed on selective media. However, none of these shoots were transformed. By co-cultivating stem internode explants with a mixed inoculum of wild-type and disarmed strains, it was possible to obtain a callus stably transformed withAgrobacterium carrying a disarmed T-DNA. Histological analysis of explants revealed that shoot regeneration initially occurred from the cells of the epidermis and subsequently from the cortex. However, the cells which were susceptible to T-DNA transfer were confined to the vascular tissue.  相似文献   
83.
The efficacies of sago (from Metroxylon sagu Rottb.) and isubgol (from Plantago ovata Forsk.) as gelling agents and those of filter paper, nylon cloth, polystyrene foam and glass wool cloth as support matrices have been tested for the propagation of plantlets of chrysanthemum (Dendranthema grandiflora Tzvelev). The performances of these low-cost gelling agents and matrices were found satisfactory and could compare well with that of agar. Glass wool cloth was, however, found to be the best matrix. Comparative cost estimations of the matrices and gelling agents have been presented and their merits and/or demerits have been discussed. For a given quantity of a medium, sago and isubgol cost about 1/18th and 1/10th respectively, compared to agar (e.g. Sigma, purified agar, No. A. 7921). The corresponding costs of the matrices are also less than that of agar. The results showed the potential of the substitutes for economic commercial application, replacing the costliest, though not indispensable, gelling agent agar.Abbreviations MS Murashige and Skoog medium (1962) - IAA indole-3-acetic acid - BA 6-benzyladenine - SEM scanning electron microscopy - m matric potential - osmotic potential  相似文献   
84.
菊花种质资源与遗传改良研究进展   总被引:17,自引:0,他引:17  
本文对菊花(Dendranthemamorifolium)种质资源的调查、搜集、研究与评价、菊花杂交育种、诱变育种和生物技术育种等方面取得的成果进行了综述,并对目前存在的问题及今后的发展方向进行了探讨.  相似文献   
85.
布洛芬对菊花插条生根、菊苗质量的影响   总被引:3,自引:0,他引:3  
孙全根 《生物技术》2001,11(6):14-15
研究了布洛芬对菊花插条生根、茎叶生长和菊苗质量的影响。结果表明,将菊花插条束蘸1000mg.L^-1布洛芬液5g然后扦插,能有效地促进菊花插条生根,显著增加平均每插条的生根数、最长根长度和根干重;并能促进菊苗生长,增加茎叶鲜重;菊苗的质量明显提高。  相似文献   
86.
Sixteen xanthophylls were isolated from the petals of chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura). Among them, (3S,5S,6R,3'R,6'R)-5,6-dihydro-5,6-dihydroxylutein (1) and five di-Z geometrical isomers of lutein-5,6-epoxide, i.e., 9Z,13'Z (2), 13Z,9'Z (3), 9'Z,13'Z (4), 9Z,13Z (5), and 9Z,9'Z (7), had never before been identified as natural products. All of the carotenoids isolated from chrysanthemum, except for (9Z)-violaxanthin, are beta,epsilon-carotene (alpha-carotene) derivatives. The analyses indicate that carotenoids from the petals of chrysanthemum have a very characteristic composition.  相似文献   
87.
涝渍胁迫下5种菊花近缘种属植物生理特性   总被引:3,自引:0,他引:3  
尹冬梅  陈发棣  陈素梅 《生态学报》2009,29(4):2143-2148
采用土培模拟涝害的方法,对5种菊花近缘种属植物的根系活力、叶绿素含量和光合生理特性以及涝渍胁迫后的形态表现进行研究和观察,比较了其耐涝能力.结果表明:涝渍胁迫下,5种菊花近缘种属植物根系活力急剧下降,但紫花野菊在胁迫初期表现出强的根系活力;5种植物叶绿素含量总体呈现先升后降的趋势;涝渍胁迫15d时纪伊潮菊、泡黄金菊的光合强度明显降低,CO2同化作用下降,并出现负值,叶片已丧失光合作用能力,其次是大岛野路菊和那贺川野菊,而紫花野菊维持了一定水平的净光合速率.结合叶片外观形态观察发现,紫花野菊最为耐涝,泡黄金菊最不耐涝,而大岛野路菊、纪伊潮菊和那贺川野菊的耐涝性介于两者之间.  相似文献   
88.
栽培菊花与矶菊属间杂交亲和性及F1结实特性研究   总被引:4,自引:0,他引:4  
研究菊属栽培小菊‘奥运火炬’、‘意大利红’与亚菊属矶菊的杂交亲和性和结实性,以及杂种F1自交、回交和开放授粉的结实特性。结果表明:无论是以栽培菊花还是矶菊为母本,父本花粉在柱头上均能很好萌发,但结实率较低,‘奥运火炬’和矶菊杂交结实率为每花序3.72粒,‘意大利红’和矶菊正反交结实率分别为每花序1.20粒和0.87粒。回交组合(‘奥运火炬’×矶菊)F1ב奥运火炬’结实率为0~1.24粒;‘意大利红’与矶菊正反交F1无论是以‘意大利红’还是以矶菊为回交父本,结实率均较低,为0~1.37粒;‘早意大利红’和矶菊正反交F1自交不结实,‘奥运火炬’×矶菊杂种F1自交仅有少数单株有一定结实性,但在开放授粉条件下结实率均较高,最高达每花序47.5粒,说明F1雌配子发育良好,回交结实率低的原因可能在于远缘杂交障碍,而自交结实率低可能由自交不亲和机制决定。  相似文献   
89.
神农香菊Dendranthema indicum(L.)Des Monl. var. aromaticum Q. H. Liuet S. F. Zhang,是湖北新发现的一种香料资源植物[1],并有药用价值,是医药和轻化工业的优良原料[2],具有广阔的开发前景。  相似文献   
90.
Population parameters of the melon aphid, Aphis gossypii Glover, were compared for insects grown on six cultivars of chrysanthemum, Dendranthema grandiflora Tzvelev ('Fontana', 'Iridon', 'Pink Lady', 'Splendor', 'White Diamond', and 'White View Time') fertilized with 3 different levels of nitrogen (80, 160 and 240 mg N/l) and 2 levels of irrigation (high 300 ml and low 210 ml every other day). Fecundity, longevity, and survivorship of aphids were significantly affected by the cultivar treatment, but were not affected by irrigation or fertilizer treatments or by any combination of interactions among cultivar, fertilizer and irrigation. Significantly fewer aphids survived on the cultivar 'Pink Lady' (populations reduced by 20.8%) than any other cultivar examined. Intrinsic rates of increase r m , finite rates of increase (R 0), and population doubling times (DT) for aphids were different among fertilizer levels and cultivars, but were not different among irrigation levels. There were no significant fertilizer by irrigation interaction effects upon r m , R 0, or DT. The highest rate of fertilizer applied (240 mg N/liter) adversely affected the intrinsic rate of increase of melon aphids; however, aphid intrinsic rate of increase was weakly correlated with foliar soluble protein levels (r=0.989, P=0.0954). Foliar soluble protein levels were not associated with fertilization treatment. Melon aphids perform consistently better on the cultivars 'White Diamond', 'Fontana', and 'Splendor', relative to those aphids growing on 'Iridon', 'Pink Lady', or 'White View Time'. In general, melon aphids performed best on 'White Diamond' and poorest on 'Pink Lady'.  相似文献   
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