蕙兰种子根状茎培养与愈伤组织诱导

以蕙兰种子无菌萌发的根状茎为材料,采用不同的激素配比以及不同的有机添加物,研究根状茎增殖和蕙兰愈伤组织诱导的适宜配方。研究结果表明:在蕙兰根状茎增殖的研究中添加100 g·L^-1香蕉泥在增殖率、分支数以及增加长度上均优于添加100 g·L^-1土豆泥;蕙兰根状茎出芽最佳的培养基:MS+2.0 mg·L^-1 NAA+4.0 mg·L^-1 6 BA+1.0 g·L^-1酪蛋白+1.0 g·L^-1蛋白胨+15 g·L^-1蔗糖+15 g·L^-1葡萄糖;诱导愈伤组织活力好并且诱导率高的培养基配方为MS+0.5 mg·L^-1 2,4 D + 1.0 mg·L^-1 NAA+1.0 mg·L^-1 6 BA+100 g·L^-1椰汁+30 g·L^-1 蔗糖。     

蕙兰不同盆栽深度对其生长影响初探

以中国蕙兰下山驯化苗为试材,研究北方日光温室中不同盆栽深度对其生长的影响.结果表明:浅栽(假鳞茎处于基质表面)有促进植株提前老化和衰退的趋势;传统栽培深度(假鳞茎基部在基质表面以下)下其叶片生长充分,根系较长,但病害发生较严重;深栽(基质表面位于叶片分批处)促进兰株生长健壮,有利于植株的更新复壮,但新芽萌发较少.     

Mechanism of herbicidal activity of a new cyclohexane-1,3-dione, tepraloxydim to Poa annua L.

Tepraloxydim [(EZ)‐(RS)‐2‐{1‐[(2E)‐3‐chloroallyloxyimino]propyl}‐3‐hydroxy‐5‐perhydropyran‐4‐ylcyclohex‐2‐en‐1‐one] showed high activity against annual bluegrass (Poa annua L.), which is relatively tolerant to sethoxydim [(±)‐2‐(1‐ethoxyiminobutyl)‐5‐[2‐(ethylthio)propyl]‐3‐hydroxycyclohex‐2‐en‐1‐one]. Absorption and translocation rates of tepraloxydim and sethoxydim were higher in P. annua than in Setaria faberi, but the absorption and translocation patterns of tepraloxydim in the two plants were similar to those of sethoxydim. Metabolic rates of tepraloxydim and sethoxydim in P. annua and S. faberi were found to be similar. The concentration for 50% inhibition (I₅₀) of acetyl‐coenzyme A carboxylase (ACCase) with tepraloxydim was approximately 3 × 10^?6 mol L^?1 for P. annua and 7 × 10^?7 mol L^?1 for S. faberi. For sethoxydim, the I₅₀ was found to be 2 × 10^?6 mol L^?1 with the enzyme of S. faberi, while sethoxydim showed a slight effect on ACCase from P. annua activity, even at 10^?4 mol L^?1. The strong inhibition of ACCase with tepraloxydim is considered to be the major factor contributing to the high herbicidal activity against P. annua. Measuring the whole plant growth response, the ratio of the tepraloxydim I₅₀ dose of P. annua to that of S. faberi (P/S) was found to be 2.4, while the P/S ratio of sethoxydim and a tepraloxydim analog with a propyl chain at R₂ were 56.3 and 73.3, respectively. The herbicidal activity against P. annua was remarkably influenced by the length of the R₂ alkyl chain, while the effect on S. faberi was not affected. Acetyl‐coenzyme A carboxylase from P. annua also exhibited a higher resistance to the tepraloxydim analog with a propyl chain than to tepraloxydim. These results suggest that a binding site structure of cyclohexane‐1,3‐diones in the ACCase differs between P. annua and S. faberi.     

ABA和PP333对蕙兰抗寒性的影响

为探讨植物生长调节剂ABA和PP333对蕙兰低温胁迫下抗寒性指标的影响,以蕙兰名品‘大一品’为试验材料,采用不同浓度的ABA和PP333对‘大一品’幼苗叶片进行叶面喷施处理,于光照培养箱[昼温/夜温=(5±0.5)℃/(0±0.5)℃]中进行低温处理,研究ABA和PP333对蕙兰抗寒性指标的影响。结果表明：ABA和PP333处理均降低了受低温胁迫的蕙兰叶片的相对电导率,提高了游离脯氨酸、可溶性糖含量和POD活性,对冷害具有缓解作用,所有处理中以15 mg/L和20 mg/L ABA处理效果最好。     

蕙兰B类MADS-box基因的克隆及表达分析

 采用RT-PCR结合RACE技术从蕙兰（Cymbidium faberi）中分离到3个B类MADS-box基因CfGLO、CfDEF1和CfDEF2,分别编码210、222和227个氨基酸。系统进化树分析显示,CfGLO属于PI/GLO类基因,CfDEF1和CfDEF2分别属于PaleoAP3组基因的PeMADS2类基因和PeMADS3类基因。RT-PCR和实时荧光定量表达分析表明,CfDEF1在2、3轮花器官侧瓣、唇瓣和蕊柱中强烈表达,在萼片中不表达;CfDEF2在1、2、3轮花器官中都表达,在营养组织中不表达;而CfGLO在所有组织中都表达,说明3个基因在蕙兰花器官的形成过程中可能扮演着不同的角色。此外,3个基因都在蕙兰幼嫩子房中有表达,显示其可能在蕙兰子房的形成过程中起一定作用。     

稀土钕对中国兰花品种线粒体酶活力及其同工酶的影响

采用不同浓度的NdCl3营养液,对中国蕙兰进行根、叶表面喷施培养,分析了蕙兰根部线粒体抗氧化酶SOD、呼吸代谢酶COX活性及同工酶的变化,结果表明:营养液中NdCl3浓度分别为60、80、100 mg/L时,COX-5同工酶被激活,NdCl3浓度为60 mg/L时的COX活性最高;营养液中NdCl3浓度分别为80、10...     

小陇山林区蕙兰生境调查

以小陇山林区蕙兰为研究对象,通过野外调查观测,分析了蕙兰在小陇山林区的分布情况及群落结构特征。结果表明:1)蕙兰分布于106°10′169″~106°21′643″E、33°44′526″~34°08′903″N范围内,海拔925~1 350 m之间;2)蕙兰多生于次生阔叶林,常绿、落叶阔叶混交林或常绿针阔混交林下,坡度17°~47°之间;3)蕙兰呈团块状不连续分布。     

秦岭地区春兰和蕙兰的花挥发性成分研究

采用顶空固相微萃取和气相色谱-质谱联用技术（HS–SPME–GC–MS）对原产于秦岭不同地点的春兰和蕙兰的鲜花进行了挥发性成分测定。结果表明该地区春兰的花中挥发性成分有40多种,主要成分有3–乙基–2–甲基–1,3–己二烯、(E)–2–辛烯醛和2–壬烯醛等;不同产地的春兰花中主要的挥发性物质构成比较类似,花香类型比较单一,且多数为无香型。而该地区蕙兰的花中挥发性成分多达50种以上,主要成分有(E)–橙花叔醇,二十二碳六烯酸和[1à,2à(Z)]–茉莉酸甲酯等。蕙兰花中挥发性成分中大多为有芳香味的物质,从而使得蕙兰的花具有更浓郁的香味。此外,蕙兰花挥发性成分构成也比春兰复杂,因此比春兰具有更多的花香类型。     

Glutathione transferases and herbicide detoxification in suspension-cultured cells of giant foxtail (Setaria faberi)

Glutathione transferases (GSTs) catalysing the conjugation of 1-chloro-2,4-dinitrobenzene, the chloro-s-triazine herbicide atrazine, the chloroacetanilide herbicides metolachlor and alachlor and the diphenyl ether herbicide fluorodifen have been identified in suspension-cultured cells derived from the grass weed giant foxtail (Setaria faberi Herrm.). In contrast to suspension-cultured cells of maize, where atrazine-conjugating GSTs are lost during de-differentiation, the GSTs active toward this herbicide in S. faberi plants were also expressed in cultures, suggesting that these isoenzymes are subject to different regulation in the crop and weed. As a result, glutathione conjugation was the major route of atrazine metabolism in S. faberi cultures. Activities of these GSTs were maximal three days after sub-culturing when the cells were dividing most actively, when they were determined to be in the order CDNB>alachlor>metolachlor= fluorodifen>atrazine. This indicated that GSTs which are enhanced during cell division can metabolise herbicides. On the basis of activity per mg protein, GST activities in the cultures were between 20 and 60-fold higher than those determined in the foliage of S. faberi seedlings. The GSTs with activity towards CDNB were resolved into three peaks following anion-exchange chromatography at pH 7·8 using Q-Sepharose. Peak 1 GSTs were not retained, while peak 2 and peak 3 were sequentially resolved with an increasing concentration of salt. Peak 1 GSTs showed activity toward metolachlor and atrazine but showed little activity toward fluorodifen. Peak 2 and peak 3 GSTs were active toward atrazine and metolachlor, with peak 3 being particularly associated with activity toward fluorodifen. The GSTs in these peaks were then further purified using S-hexyl-glutathione-agarose affinity chromatography. In each case, the affinity-bound fraction of the GSTs consisted of 28 kDa and 26 kDa polypeptides, suggesting that the GST isoenzymes in S. faberi cultures are composed of related subunits. Our results demonstrate that the GST isoenzymes involved in herbicide metabolism in suspension cultures of a grass weed show a similar level of complexity to that determined in maize cell cultures. © 1998 SCI