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991.
陕西省油松良种基地生产能力分析 总被引:3,自引:1,他引:3
对陕西省己建成的油松良种基地现实良种生产数量和质量分析结果表明,良种的遗传品质和播种品质基本上达到了营建初级种子园的目的,但基地生产能力较低,良种数量远远满足不了造林用种的需要。并对加强良种基地管理,提高良种生产能力提出了一些看法。 相似文献
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Seeds of Celtis australis were collected from 13 different sources, ranging from 550 to 1980 masl, in Central Himalaya, India. Significant (p = 0.05) variations were observed for seed traits among provenances. However, among various characters, seed weight exhibited
maximum variation between seed populations compared to other morphological characters. Between provenances, seed weight ranged
from 47.8 to 83.1 g/1000 seed, with mean value of 66.9 ± 10.7 g/1000 seed. Significant (p = 0.01) positive correlation was found between morphological characters of seeds including seed weight and elevational range
of seed source. For one year old seedlings, average shoot and root growth was 61.1 ± 13.3 and 30.5 ± 5.4 cm, respectively,
irrespective of provenance variation. Inter-comparing biomass yield of the seedlings with altitude, average biomass production
was 8.4 ± 2.5, 9.4 ± 3.3 and 12.7 ± 1.7 g/plant, respectively, for low (550–1000 masl), middle (1050–1250 masl) and high (1350–1980 masl)
altitudinal populations. Significant (p = 0.01) positive correlation between growth performance of seedlings and altitude of the seed source was recorded. Across
the provenances, shoots had the highest proportion of total biomass (42.3%), followed by leaves (32.6%) and roots (24.6%).
Among various provenances, Badiyargaon, Agroda, Guptakashi, Jakholi, Gajeli, Srinagar and Palampur populations produced heavier
seedlings and grew faster compared to seedlings of other sources. 相似文献
995.
Elliott Stephen Kuarak Cherdsak Navakitbumrung Puttipong Zangkum Sudarat Anusarnsunthorn Vilaiwan Blakesley David 《New Forests》2002,23(1):63-70
In northern Thailand, a growing interest in restoring forests for wildlife conservation and environmental protection is increasing demand for high quality planting stock of a wide range of native forest tree species. Since most native tree species have never been grown in nurseries, their production is hindered by a lack of knowledge of basic propagation methods. Basic data on germination and performance of ten indigenous framework tree species, Castanopsis acuminatissima, Dalbergia rimosa, Diospyros glandulosa, Eugenia albiflora, Ficus glaberrima var. glaberrima, Lithocarpus craibianus, Melia toosendan, Prunus cerasoides, Quercus semiserrata and Spondias axillaris were collected during the production process. Different species produce seeds at different times of the year and they have different growth rates, yet saplings must attain a plantable size by the optimum planting time i.e. the start of the wet season. Germination percentages ranged from 38 to 89%, and the time in the nursery to reach a plantable size ranged from 119 days for Prunus cerasoides, when it had reached a mean height of 48.6 cm (SD 7.9), to 609 days for Lithocarpus craibianus, when it had reached mean height of 40.5 cm (SD 10.6). This paper discusses the scheduling of production for these candidate framework species. 相似文献
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997.
Following dispersal from the parent tree, seeds of yellow-cedar (Chamaecyparis nootkatensis[D. Don] Spach) exhibit low germination, primarily as a result of coat-imposed dormancy. Dormancy of the mature (intact) seed is effectively terminated by traditional warm/cold treatments. A chemical treatment using the anaesthetic 1-propanol combined with a three day warm water soak (30 °C), a two day GA3 treatment and 60 d of moist chilling not only promotes high germinability of yellow-cedar seeds, but also elicits vigorous post-germinative growth following seedling emergence under nursery greenhouse conditions. Here we compare the effectiveness of the more traditional warm/cold treatments with the chemical treatment in terms of their capacity to elicit vigorous growth and establishment in natural stands following transplant of seedlings from a nursery greenhouse environment. Two seed lots (42313 and 43697) and open-pollinated seed from parent trees 13-6 and 19-8 showed equivalent seedling growth in natural stands following the chemical treatment and two traditional warm/cold treatments typically used for dormancy breakage by the forest industry and by the Ministry of Forests in British Columbia. The chemical protocol offers the advantage of reducing the time required to break seed dormancy. We have now demonstrated that it yields seedlings that exhibit vigorous growth and are capable of withstanding the vagaries of the environment. 相似文献
998.
本文描述了红皮云杉的最佳播种量的研究,结果表明,其最佳播种量为15kg/mu,这不但可以节约种子,而且还可以提高苗木质量。 相似文献
999.
兴安落叶松种子园花期防冻措施的研究 总被引:2,自引:0,他引:2
对兴安落叶松种子园进行调查表明,1989年雌花冻害为46.7%,1990年雌雄花冻害平均为94.2%,说明花期冻害严重地影响种子的产量和质量。经研究证明,通过培雪,推迟母树的物候期,解决了母树花期冻害问题,试验发明,75cm培雪覆草降低冻害率92.4%,效益显著。 相似文献
1000.
Natural regeneration of stone pine (Pinus pinea L.) stands in the Central Range of Spain can be difficult to attain. The success of this regeneration is affected by factors
such as the total amount of seed available, the short dispersal ability of the pinyon, the conditions required for germination,
specific problems associated with the establishment, early survival of the seedlings due to severe summer heat and drought,
competition for water and mineral resources and grazing damage. This study focuses on seed availability. The amount of available
seeds depends on the number and size of the cones and the number of viable pinyons within the cones. In stone pine stands,
both variables show great year to year variability. Both cone and seed production, for a given year, are also conditioned
by the vigour and health of the tree, its size, the condition and attributes of the stand and the loss of seed through pests
or predation. In this study, the main factors which influence cone and pinyon production are identified and a multivariate
model to predict annual cone and viable seed production is developed. To consider the correlation among observations coming
from the same tree, stand or year, random components are included in the model. The multivariate random structure allows for
future calibration of the model for a given year from a small additional sample of observations. It is important to know the
total amount of viable seed produced in a stand for a given year since regeneration cuttings for Stone pine should be concentrated
in high crop years. 相似文献