共查询到20条相似文献，搜索用时 250 毫秒
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浮山县苗圃于1985年春进行毛白杨斜栽埋杆育苗试验,1986年在总结试验的基础上,又用此法繁殖毛白杨苗木32亩,取得了良好的效果,平均亩产苗4100株,平均苗高1.5米,地径1.2厘米,苗木长势较好。方法是:1、母株的选取:选生长健壮、芽子饱满、根系发育好、无病虫害、木质化程度高的1年生苗,作为繁殖母株,放入清水中浸泡5—7天,使母株充分吸足水分,促进抑制物质转化和形成根原始体,以提高成活率。2、栽植母株:在巳深耕细整施足农家肥的圃地上,每隔40厘米划线定行距,挖栽植坑,坑的距离依母株的长度而定。于3月下旬将母株斜栽使其与地面的角度成5—10度,一株接一株地栽好,及时浇水,使土壤与母株的根系紧密结合。 相似文献
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<正> 白榆(又称家榆),在我省栽培历史悠久,生长快,适应性强;木材用途广泛,是群众喜爱的树种之一。白榆主要以种子繁殖为主,但种子繁殖容易改变母株的优良特性,所以在优良单株的快速繁殖过程中,多采用无性繁殖,为了探索白榆无性繁殖的新方法,我们进行了此项试验,总结如下。 相似文献
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吉林露水河林区灯台树种质资源初步研究 总被引：1，自引：0，他引：1
以吉林省露水河林区灯台树野生群体为材料,采用样地调查法对其种质资源进行初步调查与分析,结果表明:在3个样地中,以下坡位3号样地生长的植株最多,密度可达349株·hm-2,其中以胸径5~10 cm植株占优势,密度为207株·hm-2,并生长有胸径30 cm、树高16.7 m高大个体。中坡位2号样地密度也较大,为277株·hm-2,而且天然更新极好,幼苗幼树密度为214株·hm-2。在上坡位1号样地中,单位面积密度亦达到149株·hm-2。该林区林地坡度较大地段针阔混交林或杨树纯林是野生种群最为适宜的立地生境。野生植株生长发育正常,无林业有害生物与冻害危害。 相似文献
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从中国林业科学研究院林业研究所引入39个美洲黑杨×甜杨杂交无性系,在黑龙江西部高纬度高寒地区对各无性系苗期生长、越冬及抗病虫性等性状进行多年测试,选择繁殖能力强、苗期长势好、无严重病虫害、抗逆性强、能安全越冬的优良品系进行大量繁殖,建立品系评比林进行复选。经20 a时间,开展苗期品系评比、区域试验与示范,筛选出杨树新品种中雄4号杨(Populus deltoides×P.suaveolens)。该品种为雄株,具有树干通直圆满、速生、材质好、耐寒、抗旱、抗病虫和不飞絮等优良特性,适合作纸浆材等工业用材林、防护林及绿化树种。 相似文献
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药剂处理对金银花扦插繁殖的影响 总被引：6，自引：5，他引：1
探讨了2,4-D二氯本氧乙酸、IBA(吲哚丁酸)、NAA(萘乙酸)对金银花扦插繁殖的影响,结果表明,用IBA500mg·L-1浸5～10s及NAA700mg·L-1浸30s效果最好。 相似文献
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Rapid economic growth of the Khasia people has resulted from a most successful betel leaf farming system practiced within
the fringe of reserved forests, where government policies have facilitated effective use of the local people as a labour force
for production, protection and conservation of biodiversity of the surrounding forests. Khasia tribes have traditionally grown
betel leaf plants on naturally occurring trees. Deforestation is a serious problem in Bangladesh, whereas the Khasia people
living within forests are protecting trees for their livelihood, including selling betel leaf, collecting fuelwood and consuming
and selling fruits from support trees. It is a profitable yet sustainable forest production system, maintaining soil fertility,
stable production and optimal family size, and has created employment opportunities for the people living within and outside
the forests. It has enhanced the supply of socially required betel leaf to the local markets, contributed to price stability,
and generated some export revenue. However, the revenue of growers has been reduced by plant diseases and the capture of resource
rent by middlemen. Economic benefits could be further increased through government initiatives to improve management and the
marketing system.
This paper is based on a presentation at the International Conference on Economics of Sustainable Forest Management, University
of Toronto, Canada, May 20–22, 2004. 相似文献
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以四川白河自然保护区连香树为研究对象,采用访问法、样线法和样方法相结合,调查连香树的空间分布位点、种群特征和干扰因素。调查结果表明:保护区有连香树365株,适宜面积约1 995.46 hm2;海拔1 900～2 200 m区域的连香树株数占总株数的89.53%,尤其是海拔2 000～2 100 m分布最为密集(占43.01%);径级分布为纺锤形,自然更新差,种群呈不稳定状态,胸径在12～32 cm之间的有238株(占65.20%)。连香树主要分布区与传统耕作区和放牧区的重叠性高,林地转化成耕地及放牧践踏是连香树种群数量和栖息地下降的主要原因;减少人为干扰、就地保护与监测、建立天然母树园、种子繁殖和扦插是保护连香树种群的有效措施。 相似文献
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Various in vitro cultures were established from shoot tips of Ocimum americanum seedlings. Rosmarinic acid content of the in vitro produced plants as well as parent plant were determined by HPLC analysis and subjected to RAPD analysis. MS medium with BA at a concentration of 1 mg/l and 0.25 mg/l IAA supports maximum rosmarinic acid production in plants produced from cultures grown on that medium. RAPD analysis revealed 64 scorable bands from four primers, including six polymorphic bands. The band pattern revealed differences between the parent plant and the in vitro regenerated plants. Certain band changes were found in O. americanum plants regenerated in vitro, suggesting the existence of genetic variation that might affect the biochemical synthesis of plants derived from tissue culture. 相似文献
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We investigated the long-term recovery of Trillium ovatum (Liliaceae) following clear-cut logging by assessing demographic trends across a forest chronosequence that ranged in age from 2 to 424 years. In each of 20 sites across the chronosequence, we used 50 × 50 m plots to assess the population size, age and stage structure, seed production, and the spatial distribution of seedlings relative to reproductive plants. We found that Trillium populations were significantly reduced in younger sites and a significant positive relationship of population size and stand age, suggesting that population recovery following stand-replacement disturbances may take centuries. Slow recovery rates of Trillium can partly be explained by short seed dispersal distances. We found 67% of new Trillium recruits within only one meter of potential parent plants. Despite the general trend of slow recovery, a few recently disturbed populations showed fast population growth. In these cases, high rates of post-disturbance recruitment were related to the number of individuals surviving the disturbance event. We found that local, within-site seed production can most likely mitigate limited dispersal abilities of Trillium. The rate of Trillium recovery following disturbance, therefore, depends on the number of plants that have persisted through the disturbance event and serve as within-site seed sources. Our study suggests that the nature of the stand-replacement disturbance (i.e., magnitude and intensity) may be critical in determining the recovery of understory plants in managed forests. 相似文献