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五针松属裸子植物,松科松属。常绿乔木,一束五针叶,叶色蓝绿,枝叶挺拔苍劲,开花时,雄花序椭园形,雌花球卵形,淡紫红色,与针叶相映,格外情趣高雅。五针松为温带树种,喜阳、耐寒,生长缓慢,至老不衰,是优良的盆景树种,我国通常用日本五针松制作盆景,有较高的欣赏价值。五针松的繁殖可分有性繁殖和无性繁殖。有性繁殖,即种子繁殖,因繁育时间长,根桩生态特性差,很少采用。无性繁殖分有扦插、压条、嫁接等。扦插不易生根,压条法与扦插均不能形成不同生态特性的冠根共生体,嫁接繁育才能获得理想生态特性的冠根共生体。嫁接方… 相似文献
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<正>沙棘是胡颓子科沙棘属的一种落叶灌木或小乔木,具有重要的生态学价值和经济价值。沙棘育苗方法有两种:无性繁殖和有性繁殖。有性繁殖虽是沙棘最简易可行的繁育方法,但由于其杂合性很高,重要果实品种的经济指标会消失,而扦插繁殖能将性状优良的品系或单株进行有目的的繁殖。 相似文献
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为繁荣河南经济、实现银杏事业的蓬勃发展,根据我省实际,系统提出了适地适树、统筹规划,做好基因资源的收集、保存利用,大力发展良种、实行有性繁殖和无性繁殖同步发展,加速培育良种壮苗、做到科学栽植,搞好综合利用的发展银杏的技术策略。 相似文献
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Larchisoneofthemainspeciesforfast-growingandhigh-yieldplantationsinNortheastChina,especialIyLarixolgensisHerry-ItsmeanannualincrementcanevenreachlO.l-lO.6m3/hm2intheear1y3OyearsinrelativecoldYichunRegion.P1ant-ingfast-growingandhigh-yieldplanta-honsrequirehighqua1itysite.Buttherearetoolittlehighqualitysitetosatisfythede-mandoffast-growingandhigh-yieldplantationsinforestregionsofNortheastChina.MostoftheplantationshavetobeplantedonstublandofformerLarchplan-tations,Thus,#theeffectsofsecondr… 相似文献
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Poor seed germination is a significant problem for propagation of teak and it particularly hampers the deployment of genetically improved material into plantations. Seed dormancy is the putative cause for delayed and sporadic germination of teak seed but specific dormancy mechanisms have not been proven. In this paper we investigate whether physical or mechanical dormancy could affect teak germination. Physical dormancy was disproved when we observed water in every examined locule of fruit which had been immersed for 12–24 h (n = 1,700 fruits from six diverse sources). Mechanical dormancy was found to affect teak seed germination by means of valve structures which must open for the radicle to emerge. All 1,450 germinating seeds in 16 samples emerged from the endocarp via the detachment of a valve. Germination over 16 days was compared between extracted seeds (ex situ) and seeds within their endocarp (in situ) to determine the effect of mechanical dormancy on germination. Significantly greater germination of the ex situ seeds (62 ± 2% SE; n = 486) than of the in situ seeds (32 ± 2% SE; n = 564) indicated that mechanical dormancy is an important factor in the poor germination of teak. 相似文献
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Estimates suggest that intensified silviculture using improvedgenotypes could raise productivity of existing forests in Britainby 30 per cent, thus reducing reliance upon imported timber.This increase is most readily attainable in upland coniferousforests where Sitka spruce is the major species. Superior families of Sitka spruce can now be identified witha ten per cent increase in vigour over ordinary seed lots. However,supplies of improved seed will not be available in significantquantities until after 2000. Research into vegetative propagationwas begun to speed the introduction of improved material intocommerce. Early work on the propagation of superior clones failedbecause of problems of maturation. Subsequent investigationhas concentrated upon propagation of young individuals of improvedgenotypes grown from seed produced by artificial pollinationof tested clones. Techniques for larne-scale production of rootedcuttings of these improved genotypes have now been successfullydeveloped. Following favourable hancial appraisals. commercialtrials of the svstem are under way. Based on experience with Sitka spruce, three preconditions areproposed ;or largescale propagation programmes. These are useof cutting from young parents, propagation of proven superiorgenotypes, and use of the technique with material in short supply.The possible role of vegetative propagation for other commerciallyimportant conifers is discussed with only Hybrid larch consideredpromising. Some implications for broadleaves and the potentialrole of tissue culture are mentioned. 相似文献
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总结了近年来国内花木市场发展趋势及其在国民经济中的重要地位,讨论了世界各国在花木新品种培育方面的研究情况。对目前花木新品种培育、花木栽培方面所采用的主要技术手段和方法进行总结。最后提出了花木育种和栽培研究的发展趋势。 相似文献
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分析了两片杉木子代林伐桩和杉木无性系采穗圃萌条数量的遗传变异情况。结果表明:杉木子代林伐桩萌条数量在产地间、产地内家系间及组合间均存在极显著差异,并有中等以上遗传力;遗传变异系数在37%~39%之间;产地的遗传方差分量与产地内家系间的相近。伐桩萌条数量与基径粗度的关系随伐桩年龄的变化而表现不一;不同砍伐季节伐桩萌条数量也存在较大差异。杉木无性系采穗圃无性系间有效萌条数量存在极显著差异,无性系的萌芽能力有较高的重复力。 相似文献