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91.
龙胆叶肉原生质体再生愈伤组织的研究   总被引:1,自引:0,他引:1  
从龙胆试管苗的叶肉细胞分离得原生质体。培养4—5天后能见到第一次分裂,一个月后形成肉眼可见的小愈伤组织。试管苗的低温预处理是龙胆叶肉原生质体能否分裂的重要条件;似乎只有体积小的原生质体能保持持续分裂。获得的愈伤组织正在诱导器官分化。  相似文献   
92.
Pogostemon cablin (Benth.) is commercially important for its aromatic patchouli oil. Plants were regenerated through callus culture from leaf and nodal segments. Highest callusing was obtained from leaf explants in Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.8% bacto agar and 2 mg/L NAA + 0.5 mg/L BA. Shoot formation frequency was maximum (83%) with BA at 1.0 mg/L. Regenerated plantlets were rooted on MS medium with auxins. Maximum (90%) rooting was obtained using 0.5 mg/L NAA. Plantlets were grown for 4 weeks in this medium and then transferred to pots containing sterile sand in a moisture saturated glass chamber under laboratory conditions. The established plants were grown in pots filled with a mixture of sandsoilmanure (211) under natural daylight conditions in the field. The total leaf yield was increased in the tissue culture derived plants. These plants were dwarf and had higher specific leaf weight (leaf thickness) and leaf area compared to control plants.Abbreviations BA N6-Benzyladenine - 2,4-D 2,4-dichlorophenoxyacetic acid - IBA Indole-3-butyric acid - IAA Indole 3-acetic acid - MS Murashige and Skoog (1962) medium - NAA 1-Naphthaleneacetic acid  相似文献   
93.
密花香薷花蜜腺的解剖学研究   总被引:6,自引:0,他引:6  
密花香薷花密腺分布于子房基部和子房表面,属于一朵花中具二种花蜜腺类型,子房基部的盘状蜜腺由分泌表皮、产蜜组织及维管束三部分组成,分泌表皮上角质层局部有小孔。子房蜜腺由分泌表皮和产蜜组织组成。  相似文献   
94.
Four undescribed compounds ( 1 – 4 ) named pelliolatifolias A−D together with seven known compounds trans-clovamide ( 5 ), N-trans-caffeoyl-4-hydroxyphenylalanine methyl ester ( 6 ), N-trans-caffeoyl-3,4-dihydroxyphenylalanine methyl ester ( 7 ), luteolin 4’-O-β-D-glucopyrannoside ( 8 ), cis-syringin ( 9 ), trans-syringin ( 10 ), and citroside A ( 11 ) have been isolated from the methanol extract of the Pellionia latifolia leaves. Their chemical structures were elucidated based on extensive analyses of HR-ESI-MS, 1D and 2D NMR, and CD spectra. Compounds 1 – 7 , 9 and 10 showed moderate inhibition of NO production in LPS-activated RAW264.7 cells with their IC50 values ranging from 39.27 to 75.42 μM, compared to that of the positive control compound, dexamethasone, IC50 value of 14.20 μM.  相似文献   
95.
粗糙龙胆地下器官龙胆苦苷和可溶性糖含量的动态研究   总被引:4,自引:2,他引:2  
关旸  王臣  王晔 《植物研究》2004,24(3):366-368
对两个栽培地点北安和呼兰产粗糙龙胆的主要有效成分龙胆苦苷的含量和可溶性糖含量进行了研究。结果表明:龙胆苦苷含量随发育节律而波动,6月份虽然有一个积累高峰,但含水率高,不宜定为采收期,适宜采收期均应是花期和休眠期。可溶性糖含量相应在6月份出现先低后高的趋势,在生长后期则积累较多。  相似文献   
96.
Tesso H  König WA 《Phytochemistry》2004,65(14):2057-2062
The essential oil and chloroform extract of air-dried leaves of Otostegia integrifolia Benth. were investigated for the first time using analytical and preparative gas chromatography (GC), GC-mass spectrometry (MS) and NMR techniques. A total of 40 constituents including monoterpenes, sesquiterpenes, diterpenes and their derivatives were identified. A prenylbisabolane type diterpene, 1-methyl-4-(5,9-dimethyl-1-methylene-deca-4,8-dienyl)cyclohexene was identified as a major component. The chloroform extract of the leaves yielded two labdane type diterpenoids, 15,16-epoxy-3alpha,9alpha-dihydroxy-labda-13(16),14-diene and 9(13),15(16)-diepoxy-3alpha-hydroxy-16-dihydrolabda-14-ene, a saturated hydrocarbon, pentatriacontane, and stigmasterol. The structures of the isolated compounds were established by spectroscopic methods.  相似文献   
97.
异叶青兰挥发性化学成分研究   总被引:6,自引:0,他引:6  
采用毛细管气相色谱-质谱联用法对异叶青兰挥发性化学成分进行了研究,经毛细管色谱分离出184多个峰,共确认了其中154种成分,所鉴定化合物的含量占全油的83.52%。用气相色谱面积归一化法测定了各成分的相对百分含量,其主要化学成分为4-甲基噻唑、6,6-二甲基-二环「3,3,1」-庚-2-烯-2-甲醇,4-(1-甲基乙基)-苯甲醇、十六酸乙酯等。  相似文献   
98.
Approximately 40% of the calcium existing in colloidal phase of skimmilk was estimated to be hardly exchanged with the calcium psesent in soluble phase by applying a radioisotopic technique. This type of calcium was designated hard-to-exchange calcium. Hard-to-exchange calcium was absent or nearly zero in calcium caseinate dispersion or colloidal phosphate-free milk, but was present in composite calcium caseinate phosphate dispersion. It is suggested that hard-to-exchange calcium is present in a part of colloidal phosphate portion of casein micelles.  相似文献   
99.
采用测定生物量与精油提取相结合的方法来研究确定木香薷的最佳采收期。结果表明:霍山地区木香薷的最佳采收期在8月中旬。木香薷生物量的增长在前期主要表现为当年生小枝数的增加,而后期表现为当年生小枝重量的增加。从5月12日到8月17日,每100 g干重的当年生枝产精油量逐渐增加,而8月17日之后精油产量逐渐下降,以8月7日为最高达到1.62 g,得率为1.62%。  相似文献   
100.
王文采 《植物研究》2017,37(5):641-644
描述了自重庆市江津区四面山发现的荨麻科赤车属一新种和楼梯草属二新种:(1)四面山赤车,与融安赤车近缘,区别在于新种的叶的二级脉较少,2枚雌花被片有短角状突起,以及长圆形瘦果;(2)稀柱毛楼梯草,可能与托叶楼梯草近缘,区别在于新种的叶较小,雌总苞苞片,以及雄、雌小苞片均在背面具龙骨状突起,柱头由只3~4根毛组成;(3)四面山楼梯草,与长尖楼梯草近缘,区别在于新种茎的顶端被短柔毛,雄头状花序的花序梗较短,以及雄总苞苞片呈条状船形,背面具龙骨状突起。  相似文献   
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