安徽省毛竹实生苗造林苗木标准的探讨

以不同规格毛竹实生苗造林3年生试验结果为依据,综合考虑毛竹实生竹苗的生物学特性、生境地区性、苗木优质性、生产可行性、经济许可性、综合代表性等因素,制订了安徽省毛竹实生苗标准。生产实践表明,该标准对促进和提高毛竹育苗技术水平具有较大的激励作用,促进了毛竹实生苗造林质量的不断提高。     

短柄ISSR-PCR反应体系的优化

以短柄(Quercus glanduliferavar.brevipetiolata)的DNA为材料,对影响PCR扩增效果的一些因素诸如模板DNA用量、Taq酶的用量、镁离子浓度、dNTP的浓度、引物用量和牛血清白蛋白浓度等指标进行筛选和优化。结果显示适合短柄ISSR-PCR分析最适宜的PCR反应条件为:10μL PCR反应体积中,1×Taq酶配套缓冲液(10 mmol.L-1Tris-HCl,pH9.0,50 mmol.L-1KCl,0.1%Triton X-100),0.75UTaq DNA聚合酶,2 mmol.L-1MgCl2,0.2 mmol.L-14×dNTP,12 pmol引物,10 ng模板DNA,2 mg.mL-1牛血清白蛋白。短柄ISSR扩增较适宜的退火温度为54.4℃。     

激素及支持物对丰花月季快速繁殖的影响

丰花月季的茎段(含腋芽)在MS 6-BA3．000 NAA0．400或MS 6-BA3.000 NAA0.005的培养基上，腋芽能顺利萌发，采用MS 6-BA3.000 NAA0．005可以从无菌苗诱导大量丛生芽，在继代培养中，不同含量的6-BA和NAA在诱导效率上有明显的不同。以沙子替代琼脂作为支持物，诱导初代腋芽的效率比琼脂高，幼苗的生根率和移栽成活率均很高。     

8种育苗基质的思茅松嫩枝扦插育苗试验

为研究育苗基质与思茅松嫩枝扦插育苗效果间的关系,进行了8种不同基质的思茅松扦插育苗试验。结果表明,以河沙与锯末(1?2)为基质的扦插育苗成活率最高,平均成活率为82%;河沙与丹麦基质(1?2)的扦插苗平均不定根数量最多,达到5.2条/株;锯末基质扦插苗的平均不定根长最长,达5.50 cm/株;锯末与丹麦基质(1?1)的平均不定根最长值和单株不定根最长值最长分别为15 cm和21.7 cm。试验结果还表明,酸性基质有利于思茅松嫩枝扦插苗的成活,基质的总孔隙度大小影响着扦插苗根系的生长。     

思茅松1-脱氧-D-木酮糖-5-磷酸合酶(DXS)基因的克隆及功能分析

1-脱氧-D-木酮糖-5-磷酸合酶(DXS)是甲基-D-赤藓醇-4-磷酸(MEP)途径中的第一个酶,也是限速酶。本文根据思茅松(Pinus kesiya var. langbianensis(A. Chev.) Gaussen)树皮转录组数据分析结果,获得思茅松DXS基因片段,然后根据获得的基因片段设计特异引物,运用RT-PCR和RACE技术从思茅松树皮中克隆得到完整的DXS基因(PkDXS1)。PkDXS1基因的cDNA全长序列2888 bp,含有1个2223 bp的开放阅读框(ORF),编码740个氨基酸,该基因推断的蛋白与赤松(Pinus densiflora Siebold & Zucc)DXS蛋白的相似性为99%,与欧洲云杉(Picea abies(L.) H. Karst.)DXS的相似性为97%;经氨基酸序列比对,推断思茅松DXS具有高等植物DXS酶特有的叶绿体转运肽,二磷酸硫胺结合位点和转酮醇酶结构域。半定量RT-PCR检测表明树皮的创伤促进DXS基因的表达。     

Response of slash pine planted on mounds in central and southwestern Louisiana

On two silt loam flatwoods in Louisiana, use of mounds as planting sites for slash pine (Pinus elliottii Engelm. var. elliottii) was shown to be more effective than planting without mounds (untreated control) after six growing seasons in the field. Mounds formed were of two sizes: low mounds made of 550 dm³ of soil and high mounds made of 1,000 dm³ of soil. One site was in central Louisiana and had two drainage classes: a somewhat poorly drained Caddo-Messer complex and a poorly drained Caddo soil. On both drainage classes, pine survival was not affected by treatment, but the incidence of fusiform rust galls on the main stem (caused by Cronartium quercuum (Berk.) Miyabe ex Shirai f. sp. fusiforme Burdsall and Snow) was greater on trees planted on mounds. The second site was a poorly drained Caddo soil in southwestern Louisiana. At this site, there were fewer surviving pines on controls than on mounds, but the incidence of rust galls was not affected by treatment. At both sites, pines were taller and had a greater mean diameter at breast height on mounds than on controls. Mound size did not influence tree size at either site.     

First-year freeze hardiness of pure species and hybrid taxa of Pinus elliottii (Engelman) and Pinus caribaea (Morelet)

Six pine taxa were compared for freeze hardiness following 2 whole plant freeze tests carried out in early and late winter 1993–94. Pure species included slash pine (Pinus elliottii var. elliottii Engelman) (PEE), Caribbean pine (Pinus caribaea Morelet) var. bahamensis (PCB), and var. hondurensis (PCH). The same six slash pine parents served as the female parents of the pure slash pine taxon and were control pollinated to create the F₁ hybrids of slash pine × Caribbean pine var. bahamensis (F1B), the F₁ of slash pine × Caribbean pine var. hondurensis (F1H), and the backcross of slash pine × (slash pine × var. hondurensis (B1H). Four traits related to adaptation (bud set, foliage/stem damage, survival) were compared. Significant differences existing among the three species at all temperatures for both freeze tests. The 3 hybrid taxa were intermediate to parental taxa for all measured traits and only at extreme temperatures was there an indication of hybrid vigor. However, inspection of foliage damage curves to estimate temperatures at which 50 percent damage occurs indicated that the hybrids deviated from the mid parent value toward the more freeze susceptible parent. Discriminant functions which included foliage damage and survival traits provided the best segregation of taxa groupings and the combining of canonical variable 1 for these discriminant functions placed hybrids intermediate to parental taxa. Parent × taxa interaction was significant, suggesting that within these taxa, family to family variation occurred, but different maternal parents were associated with the freeze hardly families in different taxa.This is Florida Agricultural Experiment Station Journal Series No. R-04852 of the Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611     

长白鱼鳞云杉和臭冷杉的木材及其抽出物化学组成的研究

研究长白鱼鳞云杉、臭冷杉的木材及其抽出物化学组成，并分析生材与气干材、心材与边材中各种化学组成变化的规律。同时检测出抽出物中弱酸性物质、中性物质和强酸性物质的含量及弱酸性物质中树脂酸和脂肪酸的组成含量。     

微生物对长白鱼鳞云杉木材渗透性的影响

本文利用水池贮存处理木材研究了细菌对改善长白鱼鳞云杉木材渗透性的有效性。渗透性的测定采用水上升置换气流法。试验结果表明,水池贮存处理长白鱼鳞云杉气干材10周,不仅可以非常显著地增加其边材的渗透性(渗透性平均增加29倍),而且其心材渗透性亦有明显改善(平均渗透性增加1.52倍)。但心材试样渗透性增加不均匀,仅有50％的心材试样在水池贮存处理后渗透性得到了增加。渗透性增加的原因主要是由于边材和部分心材试样受到短芽孢杆菌(Bacillus brevis)等细菌的侵蚀,据电镜观察,边材大多数具缘纹孔的纹孔塞被细菌降解后形成空洞,心材的管胞内壁及具缘纹孔的纹孔缘上有细菌存在。     

钻天松无菌系建立的初步研究

摘　要:以钻天松侧枝顶芽作为繁殖材料,通过不同消毒剂处理试验,不同生长激素对外殖体愈伤组织形成的诱导,初步建立无菌系。结果表明:0.1%HgCl2 消毒时间最好为9 min;时间短,污染率高;时间过长会导致芽中毒而成活率下降。诱导钻天松愈伤组织形成的最佳培养基配方是1/2MS+ 6BA0. 2mg·L-1 + NAA0. 5mg·L-1 +IBA0.2mg·L-1,低浓度的6BA有利于愈伤组织的形成。