Cortical monoterpene variation in natural populations of Pinus sylvestris in Sweden

Cortical oleoresins were obtained from 10 natural populations of Pinus sylvestris L. from different geographical localities. Gas chromatography was used to determine quantities of individual monoterpenes. Considerable variation was found in monoterpene composition among different populations. High proportions of limonene occurred in greater percentages in trees of northern origins, while high sabinene was frequently found in southern trees. Mean proportions of limonene and sabinene in the populations were clinal with latitude. For some monoterpenes, variation coefficients as a measure of variability within populations appeared to be clinal with latitude. 85.4% of the variance in monoterpene composition was found within populations and 14.6 between populations. Discriminant analysis differentiates populations from different geographical localities into different groups. The differences in monoterpene patterns between adjacent populations were statistically nonsignificant. It is recommended that monoterpene composition be used for more general study of genetic variation, geographical distinction between different populations and seed certification purposes.     

樟子松温室容器育苗技术

樟子松温室容器育苗出苗率达95%以上,表现为生长快,造林成活率高,通过温室容器育苗缩短育苗周期,经济效益显著。     

樟子松温棚容器育苗技术

温棚樟子松容器育苗,改善了生长环境,缩短了育苗时间,苗木质量好,造林成活率高。     

针叶小爪螨对樟子松的危害及防治试验

首次在陕西榆林发现针叶小爪螨危害樟子松。经用７种化学药剂野外防治试验，其中三氯杀螨醇，克螨特，双甲脒施药３天后虫口减退均达８５％以上。     

“套笼”技术在樟子松小苗造林中的应用

沙地樟子松小苗造林采用"套笼"技术,解决了"遮阴问题"和"兔害困扰"技术难题,此法能提高造林成活率,在生产实践中大面积推广,收到了良好效果。因此,探讨"套笼"技术在樟子松小苗造林中的应用,意义重大。     

樟子松种子变异与种子品质关系的研究

樟子松（ＰｉｎｕｓＳｙｌｖｅｓｔｒｉｓｖａｒｍｏｎｇｏｌｉｃａ）是一个变异水平较高的树种，不仅其冠型、干型、皮包型、分枝角侧枝粗普遍存在变异，而且球果大小、颜色和球果表面鳞盾形状以及种子的颜色。大小也发生变异，本文着重研究变异和种子品质的关系，并分析种子变异的原因。     

在高寒地区樟子松育苗中应用外生菌根真菌的效应*

人工接种外生菌根真菌对高寒地区樟子松新播苗、移植苗的生长有明显的促进作用,苗高、地径、侧根数、干重和菌根化程度均比对照有较大提高。随着苗木生长期的延长,这种积极作用越显著。根据各项生长指标综合分析,筛选出的优良菌种为:臭红菇(Russula foetens)、牛肝菌(Boletus sp.)、血红铆钉菇(Gomphidius rutilus)。     

球毛壳菌对樟子松的侵染规律研究

榆林风沙区樟子松枯死主要发生在10—15年生幼龄林上，7月上旬至8月下旬为感病高峰期，翌年4月中旬至5月中旬为死亡高峰期。病菌孢子在整个生长季均能放散与传播，降雨节律及降雨量直接影响孢子的扩散与数量。人工接种发现：病菌的侵入期主要在6月中旬至8月中旬，潜育期半个月，侵入途径是伤口，病株感病部位及枯死枝是病原菌的越冬场所，密度高，植被盖度大的林分感病重。     

不同类型樟子松人工固沙林土壤质量的研究

从土壤微生物 ,土壤持水性、土壤物理、化学性质方面探讨不同类型樟子松人工固沙林土壤质量状况 ,得出针阔混交林比针叶纯林土壤质量高。松杨混交林、松枫混交林下微生物细菌、真菌数量分别比樟子松纯林高 1～ 3倍 ,表层枯枝落叶量比纯林高 8.5 4%～ 10 .0 2 % ,0～ 2 0cm最大持水量提高了 4～ 5个百分点。不同林分类型间土壤容重差异不大 ,混交林有降低趋势 ;养分状况表层有较明显差异 ,但深层土壤中除速效N之外 ,其它各项养分含量差异不明显 ,表明林木对土壤的改良作用是一个长期的持续过程     

Customer adapted grading of Scots pine sawn timber using a multivariate method

To define new grading rules, or to customize the ones in use in a rule-based automatic grading (RBAG) system of boards, is a time-consuming job for a sawmill engineer. This has the effect that changes are rarely made. The objective of this study was to continue the development of a method that replaces the calibration of grading rule settings by a holistic-subjective automatic grading, using multivariate models. The objective was also to investigate if this approach can improve sawmill profitability and at the same time have a satisfied customer. For the study, 323 Scots pine (Pinus sylvestris L.) boards were manually graded according to the preferences of an important customer. That is, a customer that regularly purchases significant volumes of sawn timber. This manual grading was seen as reference grading in this work. The same boards were also scanned and graded by a RBAG system, calibrated for the same customer. Multivariate models for prediction of board grade based on aggregated knot variables, obtained from the scanning, were calibrated using partial least squares regression. The results show that prediction of board grades by the multivariate models were more correct, with respect to the manual grading, than the grading by the RBAG system. The prediction of board grades based on multivariate models resulted in 76–87% of the boards graded correctly, according to the manual grading, while the corresponding number was 63% for the RBAG system.