毛白杨优良无性系抗旱性研究

采用１３个与抗旱性胶在的性状，应用数据极差标准化的方法，对３０个毛白杨无性系的抗旱性进行综合评定，排出抗旱位次。无性系７号、２５号、９８号、３０号、８５号和１４号的抗旱性较强，多性状综合评定树木的抗性可靠性高，蒸腾效率，气孔阻力和单位面积干重等性状和毛白杨的抗旱性关系较大。     

毛白杨抗寒无性系选育

利用全国毛白杨优树基因资源进行抗寒无性系选育,国内尚属首次。经８年系统研究,选育出１７个抗寒无性系,其中Ｌｘ、１１７１等７个无性系的材积超过小黑杨２３％以上,病虫害少,树干通直,无冻害。苗期复测和区域中试表明,这些抗寒无性系在北纬４０°左右,年均气温６℃以上,年平均极端最低温－２７．８℃和极值－３２．４℃的生态条件下,能正常发育生长并保持毛白杨特有的速生性,适宜在北方平川寒冷地区推广。而目前推广的三倍体毛白杨抗寒性差,冻害严重,只宜在热量条件较好的晋南推广。     

毛白杨优良无性系选育试验报告

为选择适合平原农区的优良品种，进行了毛白杨优良无性系选育试验。经过８ａ造要测定，筛选出３１１９、５０５７、００８４、３８８２、５０７３、５０４８等６个优良无性系，均为雄株，其材积生长量分别超对照（易县毛白杨雌株）的６９．１％、５３．３％、１５．４％、９．８％、４．４％、７．２％；形质指标均优于对照。     

国外对杨树湿心材的研究

杨树是我国主要速生造林树种之一。杨树的利用对我国林业和林产工业的发展有重要影响。湿心材是树木生长中的一种反常现象,在杨树中表现甚为突出,是杨树加工利用中的一大难题。国外对湿心材的研究于上世纪初即已开始,已取得许多研究成果。本文扼要介绍国外研究的进展和一些重要观点,涉及湿心材的形成,湿心材中的细菌、气体和水分,湿心材的酸度、材色、力学强度、渗透性和湿心材对干燥、人造板生产和刨削等工艺过程的影响。     

毛白杨优良无性系选育研究报告

毛白杨优良无性系选育研究报告高万斌（烟台市林业勘察设计队，２６４０００）为选择适于烟台市生长的优良毛白杨品种，我们从１９７４年开始，在省林业厅组织两次大规模选优的基础上，汇集部分省选及本市选择的毛白杨优树作为试验材料，嫁接繁育成无性系苗木，并从１９８...     

全国毛白杨优良无性系选育

经苗期对比试验,从国１０省种源的１０４７株毛白杨优良基因资源中初先同了３４个无性系进行中试,以比较速生的天然三倍体毛白杨雌株做对照。９年测定结果表明,鲁毛５０、５３１４、１４１４、５０１５和南＊毛新五个无性系的材积增益高达３０％－５８．２％,且干形直,形态变异明显,易识别,有较高的推广利用价值。     

毛白杨优良无性系抗寒性的研究

用电导仪测定了１０个毛白杨无性系１年生休眠苗经不同低温处理后的电解质渗出率，用原子吸收分光光度计测定外渗Ｋ＾＋浓度予以验证，并结合观察低温处理过的插穗在田间的展叶，生根和成活情况，评价了１０个毛白杨无性系的相对抗寒能力，确定了其适生范围。     

湿心材研究进展

笔者对国内外湿心材研究进展作了全面的概述,并提出研究中存在的问题,在此基础上提出了我国杨树湿心材未来研究方向。国外对于湿心材研究对象包括多种树种,研究的内容涉及湿心材的形成、湿心材中的细菌、液体和气体、湿心材的特征和湿心材检测等方面。我国湿心材研究的广度和深度与国外存在一定差距,杨树是我国主要速生造林树种之一,今后应该加强杨树湿心材病原、抗性育种和防治等方面的研究。     

三倍体毛白杨无性系生长性状研究

以三倍体毛白杨无性系B301、B302、B303、B304、B305、B306、B317、B318、B331、B385、B513、B517、BM13、BM19、BM27、BM86为试验材料,以易县毛白杨作为对照,进行田间试验,对各无性系的树高、胸径、材积进行逐年分析,发现B301、B303、B331、B513、B517这五个无性系树高、胸径、材积明显大于易县毛白杨.     

毛白杨无性系苗期生长参数分析

利用Logistic方程对6个毛白杨无性系苗高、地径的年生长动态进行拟合,并分析年生长动态规律及生长参数。结果表明:拟合效果显著,相关系数均大于0.900;苗高和地径的速生持续期分别为70~79 d和86~101 d,速生期内的苗高生长量占总生长量的58.9%~61.0%,地径生长量占总生长量的61.2%~65.1%;苗高、地径年生长极值与其实测值呈极显著正相关,相关系数均为0.990;苗高、地径的年生长极值均与各自的速生持续期、最大生长速度呈显著正相关。     

不同毛白杨无性系林分蓄积量的长期水氮耦合效应

【目的】研究不同田间持水量和纯氮施用量对毛白杨人工林单位面积上林分蓄积量的影响,确定毛白杨无性系最佳水氮组合方案。【方法】采用裂区试验设计在河北威县林地研究不同水氮耦合处理对不同无性系(BT17,B331,S86,1316)毛白杨林分蓄积量影响。【结果】1)无性系在不同纯氮施用量和田间持水量灌溉条件下单位面积上林分生长量有差异,S86无性系对高水肥处理响应较好,1316无性系响应较差。2)对杨树人工林进行水分灌溉管理措施时,应该设置田间持水量75%以上作为灌溉临界值同时灌溉临界值应考虑造林地区的环境条件、造林密度、林龄等因素。3)杨树人工林单位面积上纯氮施肥量范围是在100~400kg·hm^-2,且施肥量应当根据实验地区肥力等级状况进行酌量加减。【结论】在河北威县S86无性系是在田间持水量75%以上和每株施氮量160g的管理措施下能实现速生丰产的毛白杨无性系,建议在相近地区进行杨树人工林速生丰产林培育时候优先考虑。     

毛白杨新无性系引进选育研究

对引进11个毛白杨新无性系，在造林试验获取各无性系生长、形质指标，以及抗病性状等数据基础上，进行了多性状选择。结果BT17、51L-7、193、175、196、BT18、BT85等7个新无性系生长快、不蹲苗、破腹病率低，适应性强，材积生长比对照增益180．35％，是大连地区造林优良新品种，其中193、BT17、BT18为雄性不飞絮无性系，又是城镇绿化的好品种。     

毛白杨无性系纤维特性及微纤丝角的遗传分析

毛白杨(Populus tomentosa)是我国特有的白杨派珍贵乡土树种,早期的研究多集中在以生长量为改良目标的育种工作上(朱之悌,1992).由于造纸原料的短缺,发展杨树速生丰产纸浆林刻不容缓,对毛白杨木材性状的研究也日益增多(赵勇刚等,1996;顾万春等,1998;宋婉等,2000;邢新婷等,2000;2004).毛白杨的重要用途之一就是作为制浆造纸的原料.影响纸浆性能的性状很多,这些性状的表型变异受遗传因素和环境因素2方面影响,遗传因子有时能造成木材材性在无性系间的差异,有时则不然,环境和竞争的共同影响常常掩盖真实遗传差异,所以需要对影响木材材性的遗传因子进行更深入地研究.     

Effects of Planting Density on Growth of New Clones in Populus tomentosa

Effects of seven planting densities on the growth and tree form of nine 5-year-old new clones in Populus tomentosa were studied. The plantations, arranged with completely random block design, were located in Wuzhi County, Henan Province.Results indicated that effects of planting density on the diameter at breast height (DBH), individual volume and growing stock increment of all new clones in P. tomentosa were significant at the 1% level of probability, effects of planting density on the tree height increment of new clones B2 and B31 and on the live branches height (LBH) increment of new clones B5 and B30 were significant at the 5% level of probability, while the interaction between planting density and clone was not significant at the 5% level of probability. It was concluded that the degree of differences among new clones within the same planting density was different with different planting densities and traits. For short rotation industrial timber, clones B 1, B3, B4, B5, B7, B9, B31 were suitable with the density of 1 000-2 500 trees per hectare, while for bigger diameter timber, clones B1, B3, B4, B7, B9, B31 could be used with the planting density of 660-833 trees per hectare. Clonal repeatability was also different in different planting densities.     

三倍体毛白杨品种和种植密度对其叶片营养元素含量的影响

在田间试验条件下,采用裂区设计,以三倍体毛白杨无性系S1、S6、S8、S11为试验材料,以二倍体毛白杨S10为对照,采用7种种植密度A1(2 m×2 m)、A2(2 m×3 m)、A3(2 m×3.5 m)、A4(3 m×4 m)、A5(2 m×4 m)、A6(2 m×5 m)、A7(3 m×3 m),研究了不同品种和种植密度对三倍体毛白杨叶片营养元素含量的影响。结果表明:不同的无性系对三倍体毛白杨叶片中N、P、K、Ca、Mg的含量均有极显著的影响。叶片中N含量最高的是S6(27.41 g/kg),P含量最高的是S1(1.88 g/kg),K含量最高的是S8(3.59 g/kg),Ca、Mg含量最高的分别是S10(10.48 g/kg)、S11(4.61 g/kg)。不同种植密度对叶片中N元素的含量有显著的影响,其中叶片含N量最多的是A6,达26.97 g/kg。而不同种植密度的无性系叶片中P、K、Ca、Mg的含量无显著差异。相关性分析表明,各元素之间存在一定的相关性,Mg与Ca之间呈显著正相关,与K之间呈显著负相关。     

Comparison and early selection of new clones in Populus tomentosa

In our study, two experimental plantations, respectively, with 24 and 32 new clones of P. tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height (DBH) of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically sig-nificant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of beight, DBH and volume, as well as larger coefficients of variation (CV). The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BTI7 and 21J-1 were considered suitable in Weixian. hi Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi.     

三倍体毛白杨新无性系木材干缩性的遗传分析

利用 9a生三倍体毛白杨测定林的 9个无性系为试材 ,着重研究了木材干缩率的遗传学问题。结果表明 :木材干缩率在无性系间的差异都达到了极显著水平 ,并受到强度遗传控制 ;木材干缩在株内纵向的变异模式是随树高增加而降低 ;全干体积 ,径向、弦向干缩率和气干体积 ,径向、弦向干缩率无性系重复力分别为 0 89,0 95 ,0 84 ,0 6 7,0 84和 0 6 8。     

Genetic control of fiber properties and growth in triploid hybrid clones of Populus tomentosa

To better understand the genetic control of fiber properties (fiber length [FL], fiber width [FW] and coarseness [C]) and growth traits (tree height [H], diameter at breast height [DBH] and stem volume [SV]) in triploid hybrid clones of Populus tomentosa carr., genetic relationships among selected fiber properties with growth traits were examined in five-year-old clonal field trials located in Yanzhou, Gaotang and Xiangfen, China. In total, 180 trees from 10 clones were sampled from the three sites. The site had a moderate effect on FW, C and tree growth, and a highly significant (P<0.001) effect on FL and fiber length/width (FL/W). Clonal effects were also significant (P<0.05) for all studied traits except for the DBH and SV. Clone×site interactions were significant for all studied traits (except for FL). The estimated repeatability of clonal mean for FL (0.91) was higher than for FW (0.88), C (0.77), FL/W (0.74), H (0.62), DBH (0.61) and SV (0.55). Intersite genetic correlation estimates indicated that fiber properties were more stable than growth traits. Positively insignificant genetic correlation estimates between FL and growth trait and negatively insignificant genetic correlation estimates between C and growth traits were observed. This suggests that in the triploid hybrid poplar, clones selection for growth traits will not result in a significant increase or reduction in the fiber properties.