首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到11条相似文献,搜索用时 0 毫秒
1.
本文概述了杉木种子园主要种实害虫的综合治理措施。以虫情监测为基础,结合采种摘除虫害球果及强度修枝等林业技术,适时应用0.05%溴氰菊酯油烟剂防治成虫。通过5年综合治理,使杉木种子园的球果虫害率明显下降,种子产量有较大提高,取得了明显的经济、社会和生态效益。  相似文献   

2.
Twelve- to 17-year-old Douglas-fir grafts, which in 1985 received no treatment, stem girdles only (G), or girdles plus stem injection of gibberellin A4/7 (G + GA) at vegetative bud burst, were in 1987 retreated with G + GA or left untreated. Tree were untreated in 1986 and cone production the following year was very sparse. G + GA treatment in 1987 increased the 1988 production of seed cones from 465 to 1600 per tree, with a comparable increase in frequency of grafts producing a heavy crop of pollen cones. However, induction treatments applied in 1985 adversely affected seed- and pollen-cone production in 1988, independent of treatment in 1987. Cone size, total and filled seed per cone, and seed germination were little affected by treatment either year. Treatment with G + GA in 1987 only maximized the production of filled seeds (48 100/tree), although G + GA in both 1985 and 1987 (31 200/tree) was still highly effective relative to no treatment in either year (14 700/tree). The G + GA treatment adversely affected tree condition more severely than previously (or since) experienced, probably as a consequence of grafts also being subjected to prolonged late-summer droughts during each of the treatment years.  相似文献   

3.
The influence of injecting 38-year-old Larix occidentalis with gibberellin A4/7 (GA4/7) on seed and pollen cone production was studied in western Montana, U.S.A. Two natural stands thinned to several spacings in 1961 were chosen. The two widest spacings were used. In 1991, 60 trees selected for study at each site were randomly divided into two groups of similar DBH, half as controls and half injected in June 1991 with a solution of GA4/7 in ethyl alcohol. The volume injected was adjusted to the DBH of each tree (60 mg per 5 cm diameter). In June 1994, half the trees treated with GA4/7 in 1991 and half the untreated trees were injected with GA4/7 in the same manner as before. In 1992 and 1995, seed cone production increased on GA4/7-treated trees compared to the controls. Pollen cone production was significantly increased by GA4/7 treatment but only at one site. Delayed effects of GA4/7 on seed cone production was not evident in subsequent years after treatment. Foliar and shoot damage on treated trees was attributed to GA4/7 treatment but most trees recovered completely the following year. Finally, GA4/7 treatment did not affect cone length, potential seed per cone or filled seed per cone.  相似文献   

4.
The effects of top pruning on subsequent seed and pollen cone production in lodgepole pine (Pinus contorta Dougl.) grafted clones in two seed orchards were evaluated. In the older orchard (14 years old), three pruning regimes were applied: an untreated control, a moderate pruning where 25% of the crown was removed and a severe pruning where 40% of the crown was removed. In the younger orchard (ten years old), only a control pruning and a severe pruning (50% of crown removed) were applied. Five-year seed cone production was lower in treated ramets compared to controls in both orchards. However, when cumulative seed cone yields were adjusted for reduced tree heights after pruning, differences were no longer significant in the older orchard. Strong clonal variation was observed in seed cone yields in both orchards. Pollen cone development was less variable among treatments in the older orchard. In the younger orchard, controls consistently produced heavier pollen crops. Pruning recommendations for similar orchards are made and results discussed for reducing the impacts of losses in seed cone yields.Deceased  相似文献   

5.
马尾松无性系种子园结实初期异交水平分析   总被引:6,自引:0,他引:6       下载免费PDF全文
利用1993年和1994年测定数据,采用球果饱满种子百分率方法估算马尾松无性系种子园异交率。研究发现8 ̄9年生马尾松无性系种子园在结实初期自交率较高,异交水平较低。利用不同杂交组合估算的各亲本无性系在自由授粉情况下的异交率差异较大,两年中分别为44.7% ̄98.1%和30.8% ̄96.8%,平均为73.5%(标准误差SE=17.3%)和69.2%(标准误差SE=21.3%)。异交率在无性系间变异较  相似文献   

6.
Results are presented from three different field trials comparing controlled crossed materials of Norway spruce from the southern seed orchard at Lyngdal (58° N) with open‐pollinated progenies from the same mother trees standing in the northern natural forest (63–66° N). The seed orchard progenies flushed consistently later in the spring, terminated leader shoot growth later in the summer, had higher frequencies of lammas shoots, were delayed in lignification during autumn, and were 15% taller at age seven years from seed. The difference between the orchard‐ and the natural stand material appeared to be permanent from age four to age seven. It is suspected that the non‐native environment in the seed orchard could affect the genotypic performance of the seed orchard progenies.  相似文献   

7.
为提高20世纪80年代后期营建的1.5代杉木种子园遗传品质和种子产量,以子代材积增益、当代种子产量均高为标准,选择用于成年种子园提质改造的优良无性系。经综合评价,选择出了靖大30、靖大35、广洋45等可用于杉木成年种子园提质改造的优良无性系20个。采用随机区组设计的方法开展优良无性系容器育苗试验。结果表明:以高度17 cm、直径19 cm规格的容器,按体积比配置70%泥炭土、25%黄心土、5%珍珠岩的混合基质培育容器砧木苗,在砧木保留3轮底枝的部位进行嫁接,切接或舌接法培育2年生容器嫁接苗成活率达90%以上、苗高达93 cm以上。  相似文献   

8.
对英德火炬松种子园227个无性系产果量问题的研究结果表明,无性系间,株间以及年度间产果量变异很大,差异显著;产是量性状与高,径,材积生长性状呈弱相关,前后年度间以及与3年平均产量则高度相关。  相似文献   

9.
以柳河五道沟林木种子园2014年采集的日本落叶松自由授粉种子为材料,对不同方法处理的种子发芽性状进行测定与评价,结果表明:种子发芽率、发芽势、平均发芽时间、发芽指数分别为65%、19%、7.1 d和10.8。种子发芽率分别高出国家标准和吉林省地方标准20个和15个百分点,种子活力实际使用价值分别提高了44%和30%,发芽性状遗传品质显著高于一般商品种子。  相似文献   

10.
笔者分析了日本落叶松种子园的现状、存在的问题,提出了相应的技术措施,通过日本落叶松种子园改扩建技术,以加速中国亚热带亚高山区日本落叶松良种化进程。  相似文献   

11.
概述了广东省油茶种苗生产的现状和特点,分析其存在问题,并提出相应的发展对策.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号