配方施肥对泡桐林生长及土壤质量的影响

以3年生泡桐林为研究对象,探讨不同施肥配方对泡桐林生长及土壤质量的影响。结果表明：配方Ⅲ（每株试验木施肥量：0．3kg尿素＋0．18kg纯N＋0．5kg钙镁磷＋0．07kg纯P＋0．25kg氯化钾＋0．19kg纯K）为最佳施肥配方。经过配方Ⅲ处理过的泡桐林地,土壤有机质和速效氮、磷、钾含量均显著提高;根际土壤微生物数量明显增多;泡桐林的生长量也得到较大的增长。     

兰考泡桐和刺槐幼苗最适营养需要的研究

按稳态营养理论和方法,本文研究了兰考泡桐(Paulownia elongata)和刺槐(Robinia pseudoacacia)幼苗的最适营养需要。通过每天测定和调整培养液pH值和电导率,及时补偿消耗的营养物,幼苗体内营养状况和最大生长速率均保持稳定。兰考泡桐幼苗每天生长率高达25％以上,刺槐达15％。营养物利用率90％以上。确定兰考泡桐幼苗最适营养物比例为100N:75K:18P:7Ca:8.5Mg;刺槐为100N:60K:15P:8Ca:9Mg。本文还讨论了最适营养研究在育苗和林地施肥应用的前景。     

应用^32P和^86Rb对泡桐丛枝病病枝,叶吸收磷钾规律的研究

泡桐丛枝病在我国发生普遍,特别是在河南、山东和陕西关中地区危害严重,群众称之为泡桐的癌症。该病病原在1967年被日本人确定为类菌质体(MLO)。我国有不少人对这一病害作过研究,并取得了一定成绩。为了寻求更有效的防治措施,我们曾对该病进行了较为系统、全面的调查研究,对土壤中N、P、K含量的百分比值与感病指数间的关系,应用通径分析法进行研究,发现磷含量越高,发病越轻;钾含量越高,发病越重。经回归分析得知感病指数与P/K比值成反相关。在此基础上,对泡桐丛枝病病枝、叶对磷钾的吸收规律及不同种泡桐苗木吸收磷钾情况进行了同位素示踪试验。     

泡桐材变色类型的确定及变色真菌的鉴定

对泡桐材变色类型的研究表明,泡桐材变色存在着真菌变色。同时从新伐的泡桐木材中分离出两种真菌,经鉴定是链格孢菌和一种根霉菌,这两种真菌可引发泡桐木材变色。     

烟楸桐（选）一号二号选择的研究

对参试楸叶桐无性系进行了３试点多年度的测定,选出８２０１４和１３３两个优良系号,暂定名为烟楸桐（选）一号和二号。两个优良无性系均具有主干圆满通直、生长快、抗性较强的特点;５年生测定结果,单株材积分别超过对照７５．６８％～９１．１４％和４５．９１％～７８．４７％,遗传增益显著。     

我国泡桐抗丛枝病育种研究进展

从选种育种、引种和人工杂交育种三个方面介绍了我国的泡桐抗丛枝病育种方面所取得的成就，并阐述了目前泡桐抗病育种工作中存在的问题和今后的发展方向。     

Stand basal area as an index of tree competitiveness in timber intercropping

To derive optimal benefits from intercropping timber, farmers should make important initial decisions on tree species and planting density with a good understanding of their tradeoffs. Complex and data-intensive models used by researchers should be supplemented with simpler models based on easily measured parameters and easily understood competition functions. In experiments in the Philippine uplands, growth parameters of three popular farm-forestry species (Eucalyptus deglupta, E. torelliana, and Paraserianthes falcataria) were measured, along with intercropped and non-intercropped yields of maize and vegetables. The commonly used forestry parameter of stand basal area had a significant negative correlation with intercrop yields (as a percentage of non-intercropped yields). The slope of the regression line differed between species; in this study, percent yield loss per unit stem basal area growth was in the order E. deglupta > E. torelliana > P. falcataria. The relationship between stand basal area and intercrop-yield decline was tested on an independent data set from China. Intercrop yields had significant negative correlations with stand basal area of Paulownia elongata. We propose that adaptive tree-screening trials evaluate competitiveness in addition to evaluating growth and mortality. Stand basal area may be better suited to this task than more mechanistic indices such as leaf-area index as it is easy to measure, calculate, and understand, and it may serve as a better index of total (aboveground + belowground) competition. Basal area is also directly related to tree volume, and allows farmers to more easily evaluate the economic tradeoffs between tree growth and intercrop-yield declines. This revised version was published online in June 2006 with corrections to the Cover Date.     

TCS基因转化泡桐及抗病能力

泡桐(Paulownia)是经济价值较高的优良绿化造林树种.由于丛枝病的危害,每年我国林业的直接经济损失就高达数千万元,并且严重影响农民种植泡桐的积极性(杨俊秀等,2007).     

四倍体及二倍体毛泡桐截干再生特性研究

为掌握人工诱导四倍体毛泡桐保持多倍体特性情况及毛泡桐截干再生特性,笔者以5a生四倍体及二倍体毛泡桐截干再生苗为材料,对截干再生苗的倍性、出芽数、生长速率、叶片特性、叶绿素含量及光合特性等进行研究.结果表明:四倍体毛泡桐截干再生苗能很好地保持其多倍体倍性,相对于二倍体来说,出芽数较少,生长较缓慢;气孔增大,气孔密度降低;...     

陕西兰考泡桐木材构造和材性的研究

对陕西渭南产兰考泡桐木材构造和材性的研究表明,木材材质优良,利用价值与其它泡桐相当,其管孔式类型并非为单纯的环孔材或单纯的半环孔材,而是环孔材至半环孔材。