桉树染色体的染色和制片技术

通过比较不同预处理剂、染色剂对桉树根尖处理染色效果，确定出最佳的处理方法：用0．2％的秋水仙素预处理材料2～3h，固定18小时，置于1mol／L稀盐酸在60℃恒温水浴酸化6min，置载玻片切片后用改良石炭酸品红染色30min。制出的玻片显微镜观察，染色体清楚，可计数。     

鸡树条荚蒾种子生活力测定

以鸡树条荚蒾为材料,对其种子(种仁)进行TTC染色测定生活力,结果表明:在城市人工栽培条件下,种子的生活力达到98%,种子生命力强,质量优良.在不具有恒温设备的状况下,种子(种仁)的适宜染色时间应延长至48 h或更长一点时间.     

四唑染色法测定毛竹种子生活力的研究

采用染色全过程观察和正交试验方法研究了TTC浓度、温度和染色时间对毛竹种子生活力的影响,探讨毛竹种子生活力测定的最佳条件。结果表明:四唑染色法能够很好地检测毛竹种子生活力水平,估测种子的潜在发芽能力。TTC浓度、温度和染色时间在生活力测定中存在一定的线性关系。试验表明,25℃下浸种48 h待种子完全吸涨后,于30~35℃黑暗条件下、TTC浓度0.5%,染色3~4 h为毛竹种子生活力测定的最佳条件。     

枳椇种子生活力的四唑测定方法

通过对枳椇种子不同预处理、不同的TTC浓度和染色时间的设定,研究枳椇种子生活力测定的最佳条件。结果表明:四唑染色法能够准确的检测种子的生活力,测定的适宜条件为在远离胚根部位切除少部分种子组织后,室温条件下浸种24 h,去除种皮。在30℃环境下,采用0.25%的TTC溶液染色4 h,或0.75%TTC溶液染色2 h。     

食用色素对绣线菊染色效应的研究

为了丰富绣线菊压花花材的颜色,扩大其应用范围,从染色剂种类(宝石蓝、紫色、桔色、柠檬黄)、染色剂浓度、温度及花枝长短等方面研究食用色素对绣线菊花朵的染色效应。结果表明:4种食用色素均能对绣线菊很好染色,但不同色素之间略有差异,其中食用色素宝石蓝的适应性最佳,其次为紫色,桔色和柠檬黄适应性稍差,染色时间稍长;不同食用色素适宜的染色浓度和染色时间不同,其中宝石蓝为3 g/L染色2～3 h,紫色3 g/L染色3～4 h,桔色5 g/L染色3～4 h,柠檬黄5 g/L染色4～5 h;染色液温度对染色效果也有一定影响,室温(20℃左右)下,染色效果较好,而较低温度抑制绣线菊花朵对色素的吸收,染色时间长,效果较差,但温度太高也会导致花材很快失水,花朵萎蔫甚至脱落;枝条长度对染色效果没有明显影响,在染色液浓度和温度适宜条件下,均能获得较好的染色效果。     

苹果及橙类果实的生物防腐保鲜技术研究

用PRS5菌剂浸涂苹果的防腐保鲜试验表明：低温条件下，“PRS5菌剂 塑膜包装”、“PRS5菌剂 藕粉成膜”及“PRS5菌剂 羧甲基纤维素钠成膜”保鲜效果最优，120天的腐烂率仅为6．7％，相对防效达79．9％，以保鲜膜处理的苹果失水率最低，色泽新鲜。在恒温条件下，以“PRS5菌剂 塑膜包装”和“PRS5菌剂单独处理的效果最佳，120天腐烂率均为13．3％，相对防效达81．9％，但前者果实表面无皱缩，失水率较低。对脐橙而言，PRS5含量越高，防腐效果越好，失水率越低；PRS5菌剂经热处理后，相对防效可下降33．6％；一定时间内，防腐作用随处理时间的延长而增加。在自然条件下，对罗伯森脐橙的相对防腐效果(72天)高达95．15％，与优质化学防腐剂“施保克”效果相当。     

四唑染色法快速测定麻疯树种子生活力研究

根据四唑染色法测定种子生活力的原理,研究不同预处理和不同染色浓度对麻疯树种子着色速度和生活力测定值的影响,摸索出测定麻疯树种子生活力的最佳条件。结果表明,在室温条件下(25℃),种子经裂缝预处理,再经过0.5%TTC浸种24h是测定麻疯树种子生活力的最佳条件。     

鞭角华扁叶蜂蛹、卵发育起点温度和有效积温的研究

经试验测定，鞭角华扁叶蜂蛹、卵在室温条件下发育起点温度分别为8．3、8．5℃，有效积温分别为130．9℃、176．1℃；在恒温条件下发育起点温度分别为8．4℃、9．2℃，有效积温分别为127．2℃、164．9℃。     

绒毛白蜡种子发芽试验

在恒温条件下(25℃),利用不同浓度的赤霉素、双氧水、硝酸钾,对经过不同层积天数的绒毛白蜡种子进行浸种催芽试验,浸种时间均为48h.结果表明,层积后的种子,经适宜浓度的药剂浸泡后,发芽率显著提高,恒温条件下,对绒毛白蜡种子进行催芽的最高处理组合为层积50d,赤霉素浓度300mg/L,平均发芽率达93%;最经济的处理组合为层积50d,双氧水浓度0.05%,平均发芽率为89%,与对照相比,效果极显著.     

水曲柳弯翘木皮恢复平直工艺

以3.4mm厚水曲柳弯翘木皮为研究对象,研究采用不同温度的湿空气和不同时间处理对弯翘木皮扭曲度恢复程度的影响。结果表明:在干湿球温差1℃情况下,当处理温度从70℃上升到100℃,温度越高,木皮扭曲度恢复效果越好,从1h延长到3h,处理时间越长,木皮扭曲度恢复效果也越好。结合实际生产需求,生产上较佳的工艺参数为:温度90℃、干湿球温差1℃、处理时间2h。     

速生杨木染色效果的色差分析

木材染色是人工林速生材常用的一种改性处理方法.以染液温度、染色时间和染液浓度作为变化因素,对速生杨木染色效果进行色差检验,分析了染液温度、染色时间和染液浓度对速生杨木染色后色差变化趋势的影响.     

影响黄果西番莲授粉受孕率的一些因子

黄果西番莲花形大 ,其结构和显花过程对昆虫 (特别是小型昆虫 )传粉有一定限制 ,自然授粉坐果率不高。人工授粉试验表明授粉受孕率与花粉贮藏时间、花粉潮湿、授粉量和花粉种、株间来源有关 :当天采集的花粉授粉受孕率为 97.5% ;室温下保藏 1d ,受孕率为 12 .8% ,保藏 2d受孕率为 0 ;柱头粘着花粉量大 ,受孕率为 92 .5% ,败育率 13.5% ,花粉量少 ,受孕率为 2 2 .5% ,败育率为 4 0 .7% ;种、株间授粉受孕率 10 0 % ,自花授粉、同株异花授粉、同株繁殖的无性苗 ,株间授粉均不孕     

Production of Picea abies in South-east Norway in Response to Climate Change: A Case Study Using Process-based Model Simulation with Field Validation

A process-based model was used to simulate biomass production of Norway spruce under both current climate and climate change scenarios. The model was parameterized for Nordmoen in south-east Norway using real climate data for the period 1987-1989. The model was applied to predict the biomass production responses to three climate change scenarios. The results showed that net primary production (NPP) increased by 7% under an elevated annual mean air temperature of 4°C from the current 10.1 t dry mass ha -1 yr -1 . A doubled current ambient CO 2 concentration significantly increased NPP by 36%. The scenario of both elevated temperature and elevated CO 2 concentration led to an increase in the NPP of 49%, higher than the sum of the two effects acting singly. The results also showed that forest production responses to climate change depend on the conditions of climate used for reference.     

Temperature responses of growth and wood anatomy in European beech saplings grown in different carbon dioxide concentrations

Effects of temperature on growth and wood anatomy were studied in young European beech (Fagus sylvatica L.) grown in 7-l pots for 2.5 years in field-phytotron chambers supplied with an ambient (approximately 400 micromol mol-1) or elevated (approximately 700 micromol mol-1) carbon dioxide concentration ([CO2]). Temperatures in the chambers ranged in increments of 2 degrees C from -4 degrees C to +4 degrees C relative to the long-term mean monthly (day and night) air temperature in Berlin-Dahlem. Soil was not fertilized and soil water and air humidity were kept constant. Data were evaluated by regression analysis. At final harvest, stem diameter was significantly greater at increased temperature (Delta1 degrees C: 2.4%), stems were taller (Delta1 degrees C: 8.5%) and stem mass tree-1 (Delta1 degrees C: 10.9%) and leaf area tree-1(Delta1 degrees C: 6.5%) were greater. Allocation pattern was slightly influenced by temperature: leaf mass ratio and leaf area ratio decreased with increasing temperature (Delta1 degrees C: 2.3% and 2.2% respectively), whereas stem mass/total mass increased (Delta1 degrees C: 2.1%). Elevated [CO2] enhanced height growth by 8.8% and decreased coarse root mass/total mass by 10.3% and root/shoot ratio by 11.7%. Additional carbon was mainly invested in aboveground growth. At final harvest a synergistic interaction between elevated [CO2] and temperature yielded trees that were 3.2% taller at -4 degrees C and 12.7% taller at +4 degrees C than trees in ambient [CO2]. After 2.5 seasons, cross-sectional area of the oldest stem part was approximately 32% greater in the +4 degrees C treatment than in the -4 degrees C treatment, and in the last year approximately 67% more leaf area/unit tree ring area was produced in the highest temperature regime compared with the lowest. Elevated [CO2] decreased mean vessel area of the 120 largest vessels per mm2 by 5.8%, causing a decrease in water conducting capacity. There was a positive interaction between temperature and elevated [CO2] for relative vessel area, which was approximately 38% higher at +4 degrees C than at -4 degrees C in elevated [CO2] compared with ambient [CO2]. Overall, temperature had a greater effect on growth than [CO2], but elevated [CO2] caused quantitative changes in wood anatomy.     

千年桐种子吸水规律初探

采用称重法探讨了几种处理条件下千年桐种子吸水规律，表明千年桐种子吸水量随着温度的升高而增加。在室温、35℃、45℃水温下，种子饱和吸水量分别为27．80％，34．84％，48．51％，在60℃下饱和吸水量为48．51％。剥去外种皮饱和吸水量为36．34％，60℃时处理相比剥去种皮饱和吸水量高12．23个百分点，60℃水温浸泡处理是种子育苗较合适的前处理方式。     

毛竹竹片上染率影响因子研究

对毛竹竹地板的基本单元毛竹竹片进行染色试验的结果表明:染料种类不同,毛竹竹片的上染率亦不同,酸性染料更适于毛竹竹片的染色;毛竹竹片含竹节时的上染率小于不含竹节的毛竹竹片;染料浓度对毛竹竹片的上染率有重要影响,酸性大红对毛竹竹片染色时的较佳浓度为1%;染色温度对毛竹竹片的上染率有较大影响,适宜的染色温度为90℃;随着染色时间的延长,上染率逐渐增大;染料溶液适宜的pH值为4.5;与常压染色相比,真空加压染色能显著提高毛竹竹片的上染率,且随着真空加压染色时间的延长,上染率增大。     

Gas exchange,biomass, whole-plant water-use efficiency and water uptake of peach (Prunus persica) seedlings in response to elevated carbon dioxide concentration and water availability

We examined the interactive effects of elevated CO2 concentration ([CO2]) and water stress on growth and physiology of 1-year-old peach (Prunus persica L.) seedlings grown in 10-dm3 pots in open-top chambers with ambient (350 micromol mol-1) or elevated (700 micromol mol-1) [CO2]. Seedlings were supplied weekly with a non-limiting nutrient solution. Water was withheld from half of the plants in each treatment for a 4-week drying cycle, to simulate a sudden and severe water stress during the phase of rapid plant growth. Throughout the growing season, seedlings in elevated [CO2] had higher assimilation rates, measured at the growth [CO2], than seedlings in ambient [CO2], and this caused an increase in total dry mass of about 33%. Stomatal conductance, total water uptake, leaf area and leaf number were unaffected by elevated [CO2]. Because seedlings in the two CO2 treatments had similar transpiration despite large differences in total dry mass, water-use efficiency (WUE) of well-watered and water-stressed seedlings grown in elevated [CO2] was an average of 51 and 63% higher, respectively, than WUE of comparable seedlings grown in ambient [CO2]. Elevated [CO2] enhanced total biomass of water-stressed seedlings by 31%, and thus ameliorated the effects of water limitation. However, the percentage increases in total dry mass between well-watered and water-stressed seedlings were similar in ambient (53%) and elevated (58%) [CO2], demonstrating that there was no interaction between elevated [CO2] and water stress. This finding should be considered when predicting responses of trees to global climate change in hot and dry environments, where predicted temperature increases will raise evaporative demands and exacerbate the effects of drought on tree growth.     

Respiratory responses of Scots pine stems to 5 years of exposure to elevated CO2 concentration and temperature

Stem respiration in 20-year-old Scots pine (Pinus sylvestris L.) trees was examined following 5 years of exposure to ambient conditions (CON), elevated atmospheric carbon dioxide concentration ([CO2]) (ambient + 350 micromol mol(-1), (EC)), elevated temperature (ambient + 2-6 degrees C, (ET)) or a combination of elevated [CO2] and elevated temperature (ECT). Stem respiration varied seasonally regardless of the treatment and displayed a similar trend to temperature, with maximum rates occurring around Day 190 in summer and minimum rates in winter. Respiration normalized to 15 degrees C (R15) was higher in the growing season than in the non-growing season, whereas the temperature coefficient (Q10) was lower in the growing season. Annually averaged R15 was 0.36, 0.43, 0.40 and 0.44 micromol m(-2) s(-1) under CON, EC, ET and ECT conditions, respectively, whereas the corresponding values for total stem respiration were 6.55, 7.69, 7.50 and 7.90 mol m(-2) year(-1). The EC, ET and ECT treatments increased R15 by 18, 11 and 22%, respectively, relative to CON, and increased the modeled annual total stem respiration by 18, 15 and 21%. The increase in modeled annual stem respiration under EC and ECT conditions was caused mainly by higher maintenance respiration (22 and 25%, respectively, whereas the increase in growth respiration was 9 and 12%). Growth respiration was unaltered by ET. The treatments did not significantly affect the respiratory response to stem temperature; the mean Q10 value was 2.04, 2.10, 1.99 and 2.12 in the CON, EC, ET and ECT treatments, respectively. It is suggested that the increase in stem respiration was partly a result of the increased growth rate. We conclude that elevated [CO2] increased the maintenance component of respiration more than the growth component.     

速生杨木板材的染色工艺试验

采用真空加热法对杨木板材进行染色处理,利用方差和色差分析研究染液浓度、染液温度、染色时间等因素对杨木染色的效果影响。结果表明,染液浓度是杨木试件染色均匀性和上染性的第一位影响因子,其次是染色温度。染色时间达到6h后,再延长时间对染色效果改善不明显。     

预处理对尾巨桉单板染色性能的影响

采用乙醇处理、碱处理和热水处理三种方式对尾巨桉单板进行预处理,由正交试验确定最佳染色工艺并在最佳染色工艺条件下对预处理单板进行染色,然后对染色单板的着色性能、耐光色牢度及耐水色牢度进行测定。结果表明：正交试验确立的最佳染色工艺为染液温度70℃、染色处理时间45 m in和酸性蓝浓度0.2%,其中染液温度是影响染色效果的最主要因素;三种预处理方法能够提高尾巨桉单板的渗透性并对着色性能影响不大,同时会使染色处理材的耐光性小幅下降;三种预处理方式对染色材的耐水色牢度有较好的促进作用,其中热水处理最好,乙醇处理次之,而碱处理最差。