狭叶金星蕨的快速繁殖

The rapid propagation system of Huperzia serrata(Thunb.) Trev. associated fern (Parathelypteris angustifrons(Miq.) Ching) was established by culturing its prothallium. MS+1.0 mg·L^-1 NAA was the most suitable medium for prothallium proliferation. After 60 days of growing in this medium, the fresh weight of prothallium weighed twice heavier compared with one in the control medium (MS without hormone). MS without plant hormone was the optimal medium for inducing sporophyte. The shortest induction time was 22 days and the induction rate was 15%. 6-BA and TDZ showed inhibitory effect on the formation of the sporophyte. The best medium for root induction of sporophyte was MS+1.0 mg·L^-1 IAA. Within 60 days, the medium induced a mean root length of 1.72 cm and 13 roots per explant. Sporophyte grew best in water moss by which the survival rate of transplantation reached 100%.     

The response of electron transport mediated by active NADPH dehydrogenase complexes to heat stress in the cyanobacterium Synechocystis 6803

The electron-transport machinery in photosynthetic membranes is known to be very sensitive to heat. In this study, the rate of electron transport (ETR) driven by photosystem I (PSI) and photosystem II (PSII) during heat stress in the wild-type Synechocystis sp. strain PCC 6803 (WT) and its ndh gene inactiva-tion mutants △ndhB (M55) and △ndhD1/ndhD2 (D1/D2) was simultaneously assessed by using the novel Dual-PAM-100 measuring system. The rate of electron transport driven by the photosystems (ETRPSs) in the WT, M55, and D1/D2 cells incubated at 30℃ and at 55℃ for 10 min was compared. Incubation at 55 ℃ for 10 min significantly inhibited PSII-driven ETR (ETRPSII) in the WT, M55 and D1/D2 cells, and the ex-tent of inhibition in both the M55 and D1/D2 cells was greater than that in the WT cells. Further, PSI-driven ETR (ETRPSI) was stimulated in both the WT and D1/D2 cells, and this rate was increased to a greater extent in the D1/D2 than in the WT cells. However, ETRPSI was considerably inhibited in the M55 cells. Analysis of the effect of heat stress on ETRPSs with regard to the alterations in the 2 active NDH-1 complexes in the WT, M55, and D1/D2 cells indicated that the active NDH-1 supercomplex and medi-umcomplex are essential for alleviating the heat-induced inhibition of ETRPSII and for accelerating the heat-induced stimulation of ETRPSI, respectively. Further, it is believed that these effects are most likely brought about by the electron transport mediated by each of these 2 active NDH-1 complexes.     

Simulated N and S deposition affected soil chemistry and understory plant communities in a boreal forest in western Canada

Aims We conducted a simulated nitrogen (N) and sulfur (S) deposition experiment from 2006 to 2012 to answer the following questions: (i) does chronic N and S deposition decrease cation concentrations in the soil and foliage of understory plant species, and (ii) does chronic N and S deposition decrease plant diversity and alter species composition of the understory plant community in a boreal forest in western Canada where intensifying industrial activities are increasing N and S deposition. Methods Our field site was a mixedwood boreal forest stand located ~100 km southeast of Fort McMurray, Alberta, Canada. The experiment involved a 2 × 2 factorial design, with two levels each of N (0 and 30 kg N ha^-1 yr^-1; applied as NH₄NO₃) and S addition (0 and 30 kg S ha^-1 yr^-1; applied as Na₂SO₄). Four blocks were established in July 2006, each with four plots of 20 × 20 m randomly assigned to the treatments. Soil and understory vegetation were sampled and cover (%) of individual species of herb (height ≤ 0.5 m) and shrub (height 0.5–1 m) layers was determined in August 2012. Important findings Seven years after the treatments began, N addition increased dissolved organic carbon and N in the mineral soil (P < 0.05), whereas S addition decreased exchangeable cations (P < 0.05) in the forest floor. In the shrub layer, species evenness, and overall diversity were decreased by N addition (P < 0.05) due to increases in abundance of nitrophilous species and S addition (P < 0.01) due to decreased cation concentrations in soils. Total shrub cover decreased with S addition (P < 0.10). Nitrogen and S addition affected neither species richness nor evenness in the herb layer. However, permutational multivariate analysis of variance and non-metric multidimensional scaling analyses (based on plant cover) indicated that the effect of N and S addition on understory plant species composition in the both shrub and herb layers was species-specific. Addition of N decreased foliar phosphorus and potassium concentrations in some species, suggesting potential risk of N-meditated nutrient imbalance in those species. Our results indicate that long-term elevated levels of N and S deposition can negatively impact plant nutrition and decrease the diversity of the understory plant community in boreal forests in northern Alberta, Canada. However, considering that the current N and S deposition rates in northern Alberta are much lower than the rates used in this study, N and S deposition should not negatively affect plant diversity in the near future.     

The response of electron transport mediated by active NADPH dehydrogenase complexes to heat stress in the cyanobacterium Synechocystis 6803

The electron-transport machinery in photosynthetic membranes is known to be very sensitive to heat. In this study, the rate of electron transport (ETR) driven by photosystem I (PSI) and photosystem II (PSII) during heat stress in the wild-type Synechocystis sp. strain PCC 6803 (WT) and its ndh gene inactiva-tion mutants ΔndhB (M55) and ΔndhD1/ndhD2 (D1/D2) was simultaneously assessed by using the novel Dual-PAM-100 measuring system. The rate of electron transport driven by the photosystems (ETR_PSs) in the WT, M55, and D1/D2 cells incubated at 30℃ and at 55℃ for 10 min was compared. Incubation at 55℃ for 10 min significantly inhibited PSII-driven ETR (ETR^_PSII) in the WT, M55 and D1/D2 cells, and the ex-tent of inhibition in both the M55 and D1/D2 cells was greater than that in the WT cells. Further, PSI-driven ETR (ETR_PSI) was stimulated in both the WT and D1/D2 cells, and this rate was increased to a greater extent in the D1/D2 than in the WT cells. However, ETR_PSI was considerably inhibited in the M55 cells. Analysis of the effect of heat stress on ETR_PSs with regard to the alterations in the 2 active NDH-1 complexes in the WT, M55, and D1/D2 cells indicated that the active NDH-1 supercomplex and medi-umcomplex are essential for alleviating the heat-induced inhibition of ETRPSII and for accelerating the heat-induced stimulation of ETR_PSI, respectively. Further, it is believed that these effects are most likely brought about by the electron transport mediated by each of these 2 active NDH-1 complexes.     

Responses of Tamarix ramosissima ABA accumulation to changes in groundwater levels and soil salinity in the lower reaches of Tarim River, China

The Tarim River, located in central Xinjiang Uygur Autonomous Region, is situated north of the Taklimakana Desert. A reduction in groundwater levels and a concomitant increase in soil salinity have reduced vegetation in lower reaches of the river. Tamarix ramosissima is one of the dominant plant species in this riparian system. This species provides a buffer between the desert and the riparian zone, and contributes significantly to the function of the ecosystem and the maintenance of the biodiversity. Thus, an understanding of how T. ramosissima responds to changes in groundwater levels and soil salinity is necessary for ecological and economic management of this riparian system. We found a positive correlation (Pearson Correlation Coefficient = 0.80305) between T. ramosissima Abscisic Acid (ABA) and groundwater levels, and a negative correlation between ABA and soil salinity levels (Pearson Correlation Coefficient = –0.00961). From these relationships between ABA and groundwater/salinity we concluded that subsurface groundwater level of 3.12 m and soil salinity of 0.96 g/L can limit the normal growth and development of T. ramosissima; subsurface groundwater level of larger than 5.59 m and soil salinity of higher than 1.61 g/L will strongly impede the normal development of T. ramosissima. So we should take into account the resistance of plants to environmental stressors such as drought and salinity to keep the levels of salinity and groundwater on both sides of the main river within a range, in which trees, shrubs and herbs can grow well, and perform various ecological functions. Such conservation practice will not only avoid waste of water resources, but also contribute to efficient artificial water-recharge, helping to maintain the riparian zone of Tarim River and to promote “green corridor” maintenance.     

Responses of Tamarix ramosissima ABA accumulation to changes in groundwater levels and soil salinity in the lower reaches of Tarim River, China

The Tarim River, located in central Xinjiang Uygur Autonomous Region, is situated north of the Taklimakana Desert. A reduction in groundwater levels and a concomitant increase in soil salinity have reduced vegetation in lower reaches of the river. Tamarix ramosissima is one of the dominant plant species in this riparian system. This species provides a buffer between the desert and the riparian zone, and contributes significantly to the function of the ecosystem and the maintenance of the biodiversity. Thus, an understanding of how T. ramosissima responds to changes in groundwater levels and soil salinity is necessary for ecological and economic management of this riparian system. We found a positive correlation (Pearson Correlation Coefficient = 0.80305) between T. ramosissima Abscisic Acid (ABA) and groundwater levels, and a negative correlation between ABA and soil salinity levels (Pearson Correlation Coefficient = –0.00961). From these relationships between ABA and groundwater/salinity we concluded that subsurface groundwater level of 3.12 m and soil salinity of 0.96 g/L can limit the normal growth and development of T. ramosissima; subsurface groundwater level of larger than 5.59 m and soil salinity of higher than 1.61 g/L will strongly impede the normal development of T. ramosissima. So we should take into account the resistance of plants to environmental stressors such as drought and salinity to keep the levels of salinity and groundwater on both sides of the main river within a range, in which trees, shrubs and herbs can grow well, and perform various ecological functions. Such conservation practice will not only avoid waste of water resources, but also contribute to efficient artificial water-recharge, helping to maintain the riparian zone of Tarim River and to promote “green corridor” maintenance.     

Population genetics and breeding system of Tupistra pingbianensis (Liliaceae), a naturally rare plant endemic to SW China

The levels and partitioning of genetic diversity and inbreeding depression were investigated in Tupistra pingbianensis, a narrow endemic of South-east Yunnan, China, characterized by a naturally fragmented distribution due to extreme specialization on a rare habitat type. Here genetic diversity and patterns of genetic variation within and among 11 populations were analyzed using AFLP markers with 97 individuals across its whole geographical range. High levels of genetic variation were revealed both at the species level (P₉₉ = 96.012%; H_t = 0.302) and at the population level (P₉₉ = 51.41%; H_s = 0.224). Strong genetic differentiation among populations was also detected (F_ST = 0.2961; ⍬^嘦= 0.281), which corresponded to results reported for typical animal-pollinated, mixed selfing and outcrossing plant species. This result was consistent with mating patterns detected by our pollination experiments. The indirect estimate of gene flow based on ⍬^嘦 was low (N_m = 0.64). Special habitat and its life history traits may play an important role in shaping the genetic diversity and the genetic structure of this species. A pollination experiment also fail to detect significant inbreeding depression upon F₁ fruit set, seed weight and germinate rate fitness-traits. Since naturally rare species T. pingbianensis is not seriously genetically impoverished and likely to have adapted to tolerating a high level of inbreeding early in its history, we propose this species need only periodic monitoring to ensure their continued persistence but not intervention to remain viable.     

Interactions of bacteria and microflagellates in sequencing batch reactors exhibiting enhanced mineralization of toxic organic chemicals

Community level interactions were studied in non-axenic sequencing batch reactors (SBRs) being used to treat 2,4-dinitrophenol (DNP). Increasing the influent DNP concentrations from 1 to 10 μg ml⁻¹ eliminated large predatory organisms such as rotifers and ciliated protozoa from the SBRs. Under steady-state conditions at a DNP concentration of 10 μg ml⁻¹, supplemental additions of glucose enhanced DNP degradation and led to the establishment of a microbial community consisting of five species of bacteria and a variety of microflagellates. The bacteria and flagellates exhibited oscillating population dynamics in this system, possibly indicating predator-prey interactions between these two groups. Only two of the five bacteria isolated from this system could utilize glucose as a growth substrate, and one of these two species was the only organism that could mineralize DNP in the system. The other three bacteria could grow using metabolic by-products of one of the glucose-utilizing strains (Bacillus cereus) found in the reactors. Supplemental glucose additions increased the average size of bacterial floc particles to 172 μm, compared with 41 μm in SBRs not receiving glucose. It is theorized that the enhanced mineralization of DNP in this non-axenic system was attributable to increased community interactions resulting in increased bacterial flocculation in SBRs receiving supplemental glucose additions. Offprint requests to: S. K. Schmidt.     

Effects of a rainwater-harvesting furrow/ridge system on spring corn productivity under simulated rainfalls

A field experiment was conducted to determine the effects of a rainwater-harvesting furrow/ridge system (RHFRS) on water use efficiency (WUE) and grain yield of spring com in different simulated rainfall treatments. Our results showed that when rainfall supply ranged between 230 and 440 mm, the rainwater-harvesting furrow/ridge system increased surface temperature by 0.7–1°C at the depth of 10 cm and increased soil water storage by 5%–12% in the soil layer of 0–120 cm compared with the control. Emergence was also more rapid in the furrow-ridge system. Spring corn yield in the rainwater-harvesting furrow/ridge system was 83% higher in the 230 mm rainfall treatment, 43% higher in the 340 mm rainfall treatment, and 11% higher in the 440 mm rainfall treatment compared with the control. Similarly, WUE was 77% higher in the 230 mm rainfall treatment, 43% higher in the 340 mm treatment, and 10% higher in the 440 mm treatment than those of the control under the corresponding rainfalls. In summary, results from this study indicate that 440 mm rainfall during the spring corn growing season is the upper limit for which the rainwater-harvesting furrow/ridge system should be adopted.     

Anaerobic solubilisation of nitrogen from municipal solid waste (MSW)

This paper reviews anaerobic solubilisation of nitrogen municipal solid waste (MSW) and the effect of current waste management practises on nitrogen release. The production and use of synthetically fixed nitrogen fertiliser in food production has more than doubled the flow of excessive nitrogenous material into the community and hence into the waste disposal system. This imbalance in the global nitrogen cycle has led to uncontrolled nitrogen emissions into the atmosphere and water systems. The nitrogen content of MSW is up to4.0% of total solids (TS) and the proteins in MSW have a lower rate of degradation than cellulose. The proteins are hydrolysed through multiple stages into amino acids that are further fermented into volatile fatty acids, carbon dioxides, hydrogen gas, ammonium and reduced sulphur. Anaerobic digestion of MSW putrescibles could solubilise around 50% of the nitrogen. Thus, the anaerobic digestion of putrescibles may become an important method of increasing the rate of nitrogen recycling back to the ecosystem. A large proportion of the nitrogen in MSW continues to end up inland fills; for example, in the EU countries around 2 million tonnes of nitrogen is disposed of annually this way. Nitrogen concentration in the leachates of existing landfills are likely to remain at a high level for decades to come. Under present waste management practices with a relatively low level of efficiency in the source segregation or mechanical sorting of putrescibles from grey waste and with a low level of control over landfill operating procedures, nitrogen solubilisation from landfilled waste will take at least a century. This revised version was published online in June 2006 with corrections to the Cover Date.     

Environmental assessment of energy production from municipal solid waste incineration

Background, Aims and Scope During the combustion of municipal solid waste (MSW), energy is produced which can be utilized to generate electricity. However, electricity production from incineration has to be evaluated from the point view of the environmental performance. In this study, environmental impacts of electricity production from waste incineration plant in Thailand are compared with those from Thai conventional power plants. Methods The evaluation is based on a life cycle perspective using life cycle assessment (LCA) as the evaluation tool. Since MSW incineration provides two services, viz., waste management and electricity production, the conventional power production system is expanded to include landfilling without energy recovery, which is the most commonly used waste management system in Thailand, to provide the equivalent function of waste management. Results The study shows that the incineration performs better than conventional power plants vis-à-vis global warming and photochemical ozone formation, but not for acidification and nutrient enrichment. Discussion There are some aspects which may influence this result. If landfilling with gas collection and flaring systems is included in the analysis along with conventional power production instead of landfilling without energy recovery, the expanded system could become more favorable than the incineration in the global warming point of view. In addition, if the installation of deNO_x process is employed in the MSW incineration process, nitrogen dioxide can be reduced with a consequent reduction of acidification and nutrient enrichment potentials. However, the conventional power plants still have lower acidification and nutrient enrichment potentials. Conclusions The study shows that incineration could not play the major role for electricity production, but in addition to being a waste management option, could be considered as a complement to conventional power production. To promote incineration as a benign waste management option, appropriate deNO_x and dioxin removal processes should be provided. Separation of high moisture content waste fractions from the waste to be incinerated and improvement of the operation efficiency of the incineration plant must be considered to improve the environmental performance of MSW incineration. Recommendations This study provides an overall picture and impacts, and hence, can support a decision-making process for implementation of MSW incineration. The results obtained in this study could provide valuable information to implement incineration. But it should be noted that the results show the characteristics only from some viewpoints. Outlook Further analysis is required to evaluate the electricity production of the incineration plant from other environmental aspects such as toxicity and land-use.     

Preparation of ultra-lightweight sludge ceramics (ULSC) and application for pharmaceutical advanced wastewater treatment in a biological aerobic filter (BAF)

Novel media-ultra-lightweight sludge ceramics (ULSC) employed in an upflow lab-scale biological aerobic filter (BAF) were investigated for pharmaceutical advanced wastewater treatment. The influences of the volume ratio of pharmaceutical wastewater to domestic wastewater (PW/DW), hydraulic retention time (HRT) and air-liquid ratio (A/L) on chemical oxygen demand (CODCr) and ammonium (NH(4)(+)-N) of the effluent were investigated. When PW/DW of 4:1, HRT of 6 h, and A/L of 5:1 were applied, the mean effluent concentration of NH(4)(+)-N was 6.2 mg L(-1), and the maximum CODCr concentration in the effluent was 96 mg L(-1). Both NH(4)(+)-N and CODCr did not exceed the limits of the national discharge standards (NH(4)(+)-N ≤ 15 mg L(-1), CODCr ≤ 100 mg L(-1)). In addition, the BAF system showed a strong capacity of further removal from NH(4)(+)-N of the effluent.     

Identifying Stakeholders’ Views on the Eco‐efficiency Assessment of a Municipal Solid Waste Management System

Life cycle assessment (LCA) is one of the most popular methods of technical‐environmental assessment for informing environmental policies, as, for instance, in municipal solid waste (MSW) management. Because MSW management involves many stakeholders with possibly conflicting interests, the implementation of an LCA‐based policy can, however, be blocked or delayed. A stakeholder assessment of future scenarios helps identify conflicting interests and anticipate barriers of sustainable MSW management systems. This article presents such an approach for Swiss waste glass‐packaging disposal, currently undergoing a policy review. In an online survey, stakeholders (N = 85) were asked to assess disposal scenarios showing different LCA‐based eco‐efficiencies with respect to their desirability and probability of occurrence. Scenarios with higher eco‐efficiency than the current system are more desirable and considered more probable than those with lower eco‐efficiency. A combination of inland recycling and downcycling to foam glass (insulation material) in Switzerland is desired by all stakeholders and is more eco‐efficient than the current system. In contrast, institutions of MSW management, such as national and regional environmental protection agencies, judge a scenario in which nearly all cullet would be recycled in the only Swiss glass‐packaging factory as more desirable than supply and demand stakeholders of waste glass‐packaging. Such a scenario involves a monopsony rejected by many municipalities and scrap traders. Such an assessment procedure can provide vital information guiding the formulation of environmental policies.     

Quantity,Components, and Value of Waste Materials Landfilled in the United States

The current system of production and consumption needs end‐of‐life disposal to function, but the linkage between upstream production‐consumption with the downstream landfill as terminus is, at best, a tenuous, one‐way relationship, suggesting a partial system failure. A starting point to fix this link is to confront, systematically, the messy “black box” that is mixed waste landfilling, interrogate its contents locally, and determine a baseline that can be used to scale up results. Here, we develop a detailed model characterizing landfilled municipal solid waste (MSW) in the United States across the dimensions of material quantity, quality, location, and time. The model triangulates measurements spanning 1,161 landfills (representing up to 95% of landfilled MSW) and 15,169 solid waste samples collected and analyzed at 222 sites across the United States. We confirm that landfilled quantities of paper (63 million megagrams [Mg]), food waste (35 million Mg), plastic (32 million Mg, textiles (10 million Mg), and electronic waste (3.5 million Mg) are far larger than computed by previous top‐down U.S. government estimates. We estimate the cost of MSW landfill disposal in 2015 (10.7 billion U.S. dollars [USD]) and gross lost commodity value of recyclable material (1.4 billion USD). Further, we estimate landfill methane emissions to be up to 14% greater (mass basis) than the 2015 U.S. inventory. By principally relying on measurements of waste quantity and type that are recorded annually, the model can inform more effective, targeted interventions to divert waste materials from landfill disposal, improve local, regional, and national emission estimates, enhance dissipative loss estimates in material flow analyses, and illuminate the dynamics linking material, energy, and economic dimensions to production, consumption, and disposal cycles.     

软枣猕猴桃‘天源红'离体再生体系的建立

为了建立快速高效的全红型软枣猕猴桃离体再生体系,该研究以果皮、果肉均为红色的软枣猕猴桃新品种‘天源红’( Actinidia arguta)带腋芽茎段和幼嫩叶片、叶柄为外植体材料,采用组织培养的方法,研究适合其离体再生的外植体类型以及最佳植物生长物质组合。结果表明：初春带腋芽的茎段是最好的获得无菌苗的外植体材料,诱导腋芽出芽的最佳植物生长物质组合为MS＋6－BA 0.5 mg·L-1＋IBA 1.0 mg·L-1;研究发现叶柄比叶片更适合进行‘天源红’愈伤组织诱导,叶柄诱导的最佳植物生长物质组合为MS＋ZT 0.5 mg·L-1;同时,研究了不定芽增殖的最佳植物生长物质组合为MS＋ZT 1.0 mg·L-1;此外使用6－BA也可以达到较高的不定芽增殖率,在生产上可以替代ZT进行不定芽分化,即MS＋6－BA 2.0 mg·L-1＋IBA 0.5 mg·L-1;较适宜的生根培养基为1/2 MS＋NAA 0.2 mg·L-1;生根后的组培苗在珍珠岩∶泥炭∶细沙＝1∶1∶1的基质配比中能够达到98％的移栽成活率。该研究结果建立了全红型软枣猕猴桃的离体再生体系,为全红型软枣猕猴桃苗木快繁、工厂化育苗提供了技术支持,同时建立的再生体系为软枣猕猴桃遗传转化研究提供了基础。     

Characteristics and biogas production potential of municipal solid wastes pretreated with a rotary drum reactor

This study was conducted to determine the characteristics and biogas production potential of organic materials separated from municipal solid wastes using a rotary drum reactor (RDR) process. Four different types of wastes were first pretreated with a commercial RDR system at different retention times (1, 2 and 3 d) and the organic fractions were tested with batch anaerobic digesters with 2.6 g VS L(-1) initial loading. The four types of waste were: municipal solid waste (MSW), a mixture of MSW and paper waste, a mixture of MSW and biosolids, and a mixture of paper and biosolids. After 20 d of thermophilic digestion (50+/-1 degrees C), it was found that the biogas yields of the above materials were in the range of 457-557 mL g VS(-1) and the biogas contained 57.3-60.6% methane. The total solid and volatile solid reductions ranged from 50.2% to 65.0% and 51.8% to 66.8%, respectively. For each material, the change of retention time in the RDR from 1 to 3d did not show significant (alpha=0.05) influence on the biogas yields of the recovered organic materials. Further studies are needed to determine the minimum retention time requirements in the RDR system to achieve effective separation of organic from inorganic materials and produce suitable feedstock for anaerobic digesters.     

The incorporation of waste prevention activities into life cycle assessments of municipal solid waste management systems: methodological issues

Background, aim, and scope  

Municipal solid waste (MSW) management organizations commonly address both waste treatment and diversion activities in their management plans, yet the application of life cycle assessment (LCA) to MSW rarely incorporates the effects of waste prevention activities (WPAs) in an explicit manner. The primary objective of this paper is to further develop the methodological options for attributional LCAs of MSW to address waste prevention, including product reuse.     

链霉素在葡萄果粒中的残留分析及膨大剂的处理效果

以12年生‘玫瑰香’葡萄为实验材料,探讨了无核诱导剂（链霉素）在果实中的残留及对无核果粒的膨大的影响。结果表明,于盛花前3 d用赤霉酸50 mg.L-1＋链霉素400 mg.L-1的混合液浸蘸花穗,无核率达96%。果粒中链霉素的残留量在浸蘸10 d后即下降到处理日的1/10,到成熟时不足1 mg.kg-1。应用数学灰色系统理论分析表明,CPPU 5 mg.L-1+GAs 50 mg.L-1 、GAs 100 mg.L-1、GAs 50 mg.L-1和CPPU 5 mg.L-1在盛花后2周浸蘸无核处理过的‘玫瑰香’果穗,无核果粒的膨大及品质良好。     

小叶龙竹（Dendrocalamus barbatus）愈伤组织诱导及植株再生

以小叶龙竹种子为外植体,通过研究MS培养基中不同植物生长调节剂浓度组合对外植体愈伤组织诱导和不定芽分化的影响以及不同配比对生根的作用,建立了稳定的繁殖再生体系。试验结果表明愈伤组织诱导的最适培养基为MS＋2,4-D5．0mg·L-1;不定芽分化的最适培养基为MS＋2,4-D0．5mg·L-1＋6．BA1．0mg·L-1＋KT0．25mg·L-1;小苗的最适生根培养基为1／2MS＋6-BA0．5mg·L-1＋NAA1．0mg·L-1＋IBA0．4mg·L-1,建立的繁殖再生体系将为进一步利用分子生物学技术对竹类植物进行遗传改良奠定基础。