蒙古沙冬青子叶节诱导培养再生植株的研究

[目的]建立蒙古沙冬青子叶节丛生芽再生体系。[方法]以蒙古沙冬青子叶节为外植体,研究种子萌发培养基中6-BA浓度、子叶节萌发天数、丛生芽诱导的基本培养基及6-BA浓度对丛生芽诱导的影响和外源激素对丛生芽伸长及生根的影响。[结果]表明:(1)添加6-BA的萌发培养基与不添加的相比能够显著促进子叶节的生长及子叶节丛生芽的诱导,且6-BA浓度在2.0 mg·L-1时,诱导率最高可达73.3%,平均芽数2.26个;(2)种子萌发天数对子叶节丛生芽的诱导有显著影响,萌发7 d的子叶节丛生芽诱导率最高,诱导率为74.7%,但与萌发9、11 d的子叶节丛生芽诱导率差异不显著;(3)MS和B5培养基对丛生芽诱导的影响差异不显著,但B5抑制褐化的效果显著好于MS;(4)采用1.0 mg·L-16-BA+0.3 mg·L-1IAA激素组合有利于丛生芽伸长,伸长率为60.5%;(5)不同浓度生长素组合均能促进丛生芽幼苗生根,1.0 mg·L-1IBA生根率最大,生根数最多。[结论]最佳蒙古沙冬青子叶节丛生芽再生体系为:以在MS+2.0 mg·L-16-BA培养基中黑暗培养7 11 d的幼苗子叶节为外植体,在B5+1.0mg·L-16-BA培养基中诱导丛生芽,待丛生芽长约0.3 0.5 cm后,转入B5+1.0 mg·L-16-BA+0.3 mg·L-1IAA培养基中进行伸长培养,当丛生芽伸长至2 3 cm时,单株切下转入1/2 B5+1.0 mg·L-1IBA培养基中生根,该体系与愈伤组织培养相比能缩短培养时间,改善褐化严重、玻璃化等问题,可为蒙古沙冬青的扩繁及进一步开展遗传转化奠定基础。     

白林2号杨组织培养与快繁技术研究

以白林2号杨优树萌发枝条(已木质化)为外植体进行组织培养快繁技术研究,结果表明:初代分化最适培养基为MS+6-BA0.3 mg·L-1+IAA0.5 mg·L-1,分化仅为7 d,并有丛生芽发生;使用MS+6-BA0.3 mg·L-1+NAA0.01 mg·L-1+IAA0.3 mg·L-1进行继代培养效果最好,丛生芽粗壮,数量较多;以附加不同含量NAA和IAA诱导生根,可获得再生植株,其中1/2MS+NAA0.01 mg·L-1+IAA0.2 mg·L-1培养基生根率达到88%。     

蝴蝶兰丛生芽高效增殖的研究

采用正交试验L16(44)表,研究6-BA、NAA、不同附加物等对蝴蝶兰丛生芽增殖的影响。结果表明,6-BA、NAA、对蝴蝶兰丛生芽的增殖均有一定的影响,当6-BA、NAA浓度分别为5.0、1.0mg.L-1时,丛生芽的增殖系数最大,可达6.6以上。文中分析了不同附加物培养基对蝴蝶兰丛生芽增殖的影响,得到最优培养基配方为:MS+5mg.L-16-BA+1 mg.L-1NAA+10%蔗糖+15 g.L-1马铃薯。     

高粱泡组织培养技术

为了加快高粱泡的开发利用,以MS为基本培养基,以高粱泡的带芽茎段为外植体进行组织培养研究。结果表明:不同种类和浓度的激素对高粱泡不定芽增殖和生长的影响不同。最佳启动培养基为MS+0.5mg·L-16-BA,最佳增殖培养基为MS+6-BA0.5mg·L-1+NAA0.1mg·L-1,最佳生根培养基为1/2MS+0.05mg·L-1NAA。     

金合欢组织培养技术研究

以金合欢2a生优树的带芽茎段为材料,着重研究不同激素浓度及其配比对金合欢组织培养各环节的影响,探索适宜的启动、增殖、生根培养基配方.结果表明:适宜的启动培养基配方为:3/4MS+6-BA1.0 mg· L-1+IBA0.5 mg·L-1;适宜的增殖培养基配方为:MS +6-BA0.5 mg·L-1+ NAA0.3 mg·L-1+ NaH2PO440 mg·L-1,月增殖系数可达3.83;适宜的生根培养基配方为:1/2MS+ IBA0.6 mg·L-1+ NAA0.2 mg·L-1,生根率可达86％,生根效果较理想.     

香樟茎段组培快繁技术

以多年生香樟茎段为外植体,进行丛生芽的诱导和快速繁殖试验。结果表明:无菌茎段接种至MS+6-BA 0.5 mg·L-1+IBA 0.07 mg·L-1的诱导培养基中,腋芽明显萌动并伸长展叶,且萌发率为100%;在MS+6-BA 0.5 mg·L-1+NAA0.05 mg·L-1可形成大量丛生芽,平均有效芽数可达5.2个;在1/2 MS+IBA 0.05 mg·L-1生根培养基中培养20 d后,丛生芽全部生根,移栽成活率可达90%。     

巨尾桉组织培养快繁技术研究

以巨尾桉优良无性系无菌苗带腋芽的茎段为外植体,诱导产生丛生芽,探讨不同浓度无机盐对诱导产生的丛生芽黄化率的影响,并开展丛生芽壮苗和生根培养.结果表明:诱导产生丛生芽的最佳培养基为:改良MS+ZT 0.5 mg·L-1+NAA 0.2 mg·L-1;降低丛生芽黄化率的最佳无机盐离子浓度是在MS大量元素的基础上增加Ca2+和Mg2+浓度、Fe2+和Mn2+浓度;壮苗后生根最佳培养基为:改良1/2 MS+IBA 1.0mg·L-1+NAA 1.5 mg·L-1.从而建立了高效巨尾桉组培再生系统,为桉树良种选育和遗传转化等研究提供材料和基础手段.     

檀香丛生芽增殖培养的研究

研究在相同的培养条件下,不同无机盐浓度、不同激素配比与组合、不同体积分数CW对檀香丛生芽增殖生长的影响,得出最适合的檀香丛生芽增殖培养基为MS+6-BA 1.0 mg.L-1+NAA 0.1 mg.L-1+10%CW。     

青钱柳茎段腋芽萌发和丛生芽增殖

为建立高效的青钱柳组培快繁体系,以青钱柳茎段腋芽作为外植体,WPM为基本培养基,研究不同植物生长调节剂种类及其浓度组合对腋芽萌发和丛生芽增殖的影响.结果表明:9个处理的激素组合对青钱柳腋芽萌发均有不同程度的促进作用.其中,6-BA 3 mg·L-1+2ip 1 mg·L-1 +NAA 0.1 mg·L-1处理效果最佳,萌芽率最高(83.33%),芽生长状态最好,但各处理诱导的均以单芽为主.将单芽置于添加TDZ的培养基中则诱导的均为丛芽,最佳组合为TDZ 0.1 mg·L-1+NAA 0.1 mg·L-1,萌芽率、增殖系数均达最高,分别为100%和7.33.培养基中添加2.0 mg·L-1 GA,能有效地促进丛生芽的伸长生长,芽苗生长健壮,为后续生根奠定良好基础.     

窿缘桉组织培养技术研究

以28年生窿缘桉优株萌芽条的嫩茎为外植体,对窿缘桉进行了组培试验。结果表明,MS+6-BA 0.5mg.L-1对外植体始芽诱导效果较好,诱导率为72%,且丛生芽生长健壮,无玻璃化现象;在改良MS+6-BA1.5 mg.L-1+IBA 0.5 mg.L-1上继代培养,芽增殖系数3.9;单芽在改良生根培养基1/2MS+IAA 1.5 mg.L-1+NAA 1.0 mg.L-1中的生根率最好,达86%。     

Determinants of floodplain forest development illustrated by the example of the floodplain forest in the District of Leipzig

This paper discusses determinants of the historical and current spatial extent of the floodplain forest in Leipzig as well as its tree species composition using a GIS-data based delineation model and historical forest inventories for the floodplain forest in the district of Leipzig in Germany from the 19th to the 20th century. We found that the spatial extent of the floodplain forest remained considerably stable in spite of an overall decline in the entire floodplain area from the period where the city first experienced industrialisation in the 19th century to now. However, with river regulations and the alteration of forest management from coppice-with-standards forest to high forest in the 19th century, major changes can be found in the tree species composition of the floodplain forest. Comparing these findings with references from other European floodplain forests we discuss the impact of historical and current forest management as well as the city location's influence on the extent and tree species composition of urban floodplain forests. For urban forest management in particular there is a great need to integrate biophysical, historical and forestry knowledge when predicting future developmental trends.     

Optimizing the joint production of timber and bilberries

Berries and mushrooms are increasingly appreciated products of Finnish forests. Therefore, there is a need to integrate them in silvicultural planning. Bilberry (Vaccinium myrtillus L.) is an economically important wild berry that is widely collected for household consumption and sale in North Karelia, Finland. In this study, bilberry yield models developed recently were included in a stand growth simulator and the joint production of timber and bilberry was optimized by maximizing soil expectation value (SEV) with 3% discounting rate, assuming that 75% of the bilberry yield is harvested. The effect of bilberry production on the optimal stand management increased with increasing bilberry price. With high bilberry prices (4–8 € kg⁻¹) it was optimal to manage the mixed stand of Scots pine, Norway spruce and birch, and the pure stand of Norway spruce so as to promote bilberry production. In the Scots pine stand, where bilberry yields are higher, bilberry production affected optimal stand management already with a price of 2 € kg⁻¹. Compared to timber production, joint production led to longer rotation lengths, higher thinning intensities, more frequent thinnings, and higher share of Scots pine in the mixed stand. The contribution of bilberries to the total SEV increased with increasing bilberry price and discounting rate. In the mixed stand and pine stand the SEV of bilberry production, calculated with 3% discounting rate, exceeded the SEV of timber production when bilberry price was 4 € kg⁻¹.With 4% discounting rate this happened already with bilberry price of 2 € kg⁻¹. It was concluded that forest management which promotes bilberry yields is the most profitable in pine stands where the potential bilberry yields are high.     

Antimicrobial activity of some endemic plants growing in the Eastern Black Sea Region, Turkey

The Eastern Black Sea Region has an extensive flora because of ample rainfall lasting all year. In this study, antimicrobial effects of 74 crude extracts of 22 endemic plants were investigated. Among the 30 active crude extracts, water-insoluble crude extracts from Betula medwediewii, Heracleum platytaenium, Primula longipes, Anthemis cretica ssp. argaea and Centaurea helenioides were the prominent ones with their MIC values.     

Antimicrobial activity of the Derris elliptica, Derris indica and Derris trifoliata extractives

Various parts of Derris elliptica, Derris indica and Derris trifoliata on fractionation with a number of solvents (petrol, dichloromethane, ethyl acetate, butanol and methanol) gave fractions which demonstrated a varied level of broad spectrum antibacterial activity. Good activity was exhibited by the methanol fractions of the leaves and root heart-wood, petrol, butanol and methanol fractions of the root bark of D. indica and petrol and ethyl acetate fractions of D. trifoliata. None of the plants showed antifungal activity.     

Relative susceptibility of four species of African mahogany to the shoot borer Hypsipyla robusta (Lepidoptera: Pyralidae) in the moist semideciduous forest of Ghana

We examined the relative susceptibility of four mahogany species, Khaya ivorensis, Khaya anthotheca, Entandrophragma angolense, and E. utile, to Hypsipyla robusta attack. Seeds were obtained from one to three parent trees for each species. The research was conducted in the moist semideciduous forest zone in Ghana and used a randomized complete block design. Tree height and diameter and height to first branch were measured until 24 months after out-planting in the field. H. robusta damage was assessed by counting the numbers of shoots attacked, branches, and dead shoots. Khaya spp. grew better but experienced more attack than Entandrophragma spp. The relative susceptibility to H. robusta attack, from most to least, of the four species was: K. anthotheca > K. ivorensis > E. angolense > E. utile. At 24 months, the mean number of shoots attacked per tree ranged from 1.0 for an E. utile seed source to 3.6 on for a K. anthotheca seed source. At 15 months, K. anthotheca and K. ivorensis started branching at about 1.5 m, but height of clear trunk increased over time due to self-pruning. As K. anthotheca grew taller, the number of H. robusta attacks per tree declined. This suggested that selection of genotypes and species that are tolerant of H. robusta attack based on infestation of young plants may not be appropriate. Genetic factors more completely reflecting the response of different species and genotypes to H. robusta attack may manifest themselves at later growth stages.     

Antimicrobial activity of coupled hydroxyanthracenones isolated from plants of the genus Karwinskia

The in vitro activity of some isolated hydroxyanthracenones belonging to the genus Karwinskia against four bacteria, six filamentous fungi and four yeast are reported. These hydroxyanthracenones were found to possess antimicrobial activity, particularly against Streptococcus pyogenes, Candida albicans, C. boidinii, C. glabrata and Cryptococcus neoformans; minimal inhibitory concentrations range between 16 and 2 microg/ml.     

Molluscicidal activity of Solanum species of the Northeast of Brazil on Biomphalaria glabrata

Seven species of Solanum were screened for their molluscicidal properties against Biomphalaria glabrata, the intermediated host of Schistosoma mansoni, Solanum agrarium, S. jabrense, S. melissarum, S. megalonyx, S. paludosum, S. paraibanum and S. stipulaceum. Four extracts showed molluscicidal activity with LC(50) from 22 to 56 microg/ml.     

Antimicrobial activity of the Maniltoa schefferi extracts

All fractions of Maniltoa schefferi exhibited a broad spectrum of antibacterial activity. Good activity was demonstrated by the petrol and dichloromethane fractions of seed pods, seeds with coat and by methanol fractions of stem heartwood, root bark, root heartwood and stem bark whose butanol fraction was equally good. None of the fractions showed any antifungal activity.     

Nepetalactone content in shoot cultures of three endemic Nepeta species and the evaluation of their antimicrobial activity

Rapid micropropagation of Nepeta rtanjensis, N. sibirica and N. nervosa was performed. Qualitative and quantitative nepetalactone content in methanol extracts of in vitro grown plants was analysed by reverse-phase HPLC coupled with UV and MS detection. Only trans,cis-nepetalactone was detected in shoots of N. rtanjensis, while cis,trans-nepetalactone stereoisomer was present in N. sibirica. No nepetalactone was observed in shoots of N. nervosa. The antimicrobial activity of methanol extracts, against eight bacterial and eight fungal species, was evaluated. All the tested extracts showed significant antibacterial and strong antifungal activity. However, N. rtanjensis extract exhibited the best antimicrobial potential.