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很多林木种子存在难萌发、天然更新不良的现象,而种子际是直接影响种子萌发的土壤区域,种子际微生物会对天然更新的植物产生有益或有害的影响,并对解释根际微生物群落的建立具有重要的意义.文中主要从种子际微生物多样性、对种子和幼苗生长发育的影响、种子际微生物群落变化的影响因素以及种子际微生物的自身调节行为等4方面来概述种子际微生... 相似文献
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3种木本油脂植物种子活力研究 总被引:17,自引:4,他引:13
选用了3种木本油料植物即光皮树、麻疯树和续随子的种子作为试材,布置简单随机区组实验,并测定了各树种的发芽率、发芽势、发芽指数和活力指数;运用SPSS软件进行数据分析,并探讨影响种子活力指数的内在及外在因素。结果表明:种子的活力最能反映种子在实际条件下萌发速度和整齐度以及幼苗健壮生长的潜势;种子的活力指数受品种的影响最大,即主要是由于其遗传和生理上的差异;外在因素主要是水分、温度、光照等。因而种子萌发是外在因素与内在因素共同作用的结果。 相似文献
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提高林木种子生命力和安全贮藏 总被引:1,自引:1,他引:0
介绍了种子的贮藏意义、目的和国内外贮藏林木种子的研究及概况。重点论述了影响林木种子生命力的因素,介绍了国家有关种子的法律法规及国家标准《林木种子贮藏》,并对贮藏方法给予具体指导。 相似文献
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为给毛竹(Phyllostachys edulis)种子增产及资源利用提供参考,以桂林北部地区开花毛竹为研究对象,开展毛竹种子产量与表型性状相关分析,探索种子产量与表型性状间的关系。结果表明,株高、胸径、冠幅、秆节数和生殖枝条数与种子产量呈极显著正相关,空瘪率与种子产量呈极显著负相关。毛竹种子产量的影响因素多样,需各因素共同作用才能达到增产的目的。综合分析认为,秆节数、生殖枝条数和冠幅对种子产量起主导作用;空瘪率、株高和胸径对种子产量有一定作用;出籽率、百粒重和生殖枝平均粗度对种子产量影响不大。 相似文献
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林木种子贮藏的任务,是通过改善种子的贮藏条件,通过管理使种子在贮藏期间的新陈代谢和物质消耗降到最低限度,在较长时间内保持其生命力。一、影响林木种子贮藏的因素1、种子类型:种子类型是影响种子安全贮藏的主要因素。一般而言,在同等贮藏条件下,完全成熟的种子比未成熟的种子保持生命力的时间长;初始发芽率高的种子比初始发芽率低的种子贮藏效果好;种皮坚硬而不透水的种子比种皮柔软而透水的种子保持生命力的时间长;未受机械损伤的种子比受了机械损伤的种子贮藏效果好。2、种子含水量:种子含水量的多少与生命力的保存密切相关… 相似文献
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以兔儿伞(Syneilesis aconitifolia)种子为试验材料,对不同温度、光照及PEG-6000条件处理下对种子萌发特性进行了研究。研究结果表明:兔儿伞种子成熟度和光照对种子发芽率影响不大,温度是影响种子萌发的主要因素。种子萌发最适温度为15~25℃,但其耐高温和干旱,萌发前经过24 h高温(40℃)处理,发芽率达55%。高浓度PEG抑制种子萌发,而低浓度PEG促进种子萌发,种子经25%PEG处理后复水萌发,种子发芽率和出苗整齐度提高。 相似文献
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苦槠(Castanopsis sclerophylla (Lindl.) Schott.)为壳斗科(Fagaceae)栲属(Castanopsis (D. Don.) Spach.)植物[1],是亚热带地区常绿阔叶林的重要建群树种,也是亚热带常绿阔叶林次生演替阶段重要的先锋树种,对群落的组成、外貌、功能等都有一定控制作用[2].苦槠作为优良多用途树种,其生态效益、经济价值、食品保健功用及其在园林绿化中的地位已逐渐得到认可[3-4].目前,国内对苦槠的研究已有了一定基础,但对苦槠种群遗传学研究较少.种子是物种遗传变异的重要特征之一,在分类和遗传上具有重要的价值[5],种子形态不仅决定其扩散能力,也影响到种子的萌发和幼苗定植,进而影响到种群的分布格局[6].研究苦槠种子性状变异及其地理分化,对了解苦槠种群遗传分布格局具有重要意义,进而也可为苦槠天然林的保护和人工林的营建提供理论参考. 相似文献
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毛果含笑种子休眠的原因及其休眠的破除 总被引:1,自引:0,他引:1
毛果含笑为分布于云南的珍贵绿化观赏树种,其种子具有休眠习性。为解决毛果含笑种子的有效繁殖问题,从种子的形态结构,种皮的透水性、种子中的萌发抑制物质测定,种子的生活力测定及其种子萌发试验等方面,对毛果含笑种子休眠的原因及破除方法进行了研究。结果表明:种胚发育不完全和种子所含的萌发抑制物质是导致毛果含笑种子休眠的主要原因。毛果含笑种皮具有较好的透水性,与其休眠的关系不大,由此可认为毛果含笑种子的休眠类型为形态生理休眠;用蒸馏水浸泡或赤霉素液浸泡种子均可有效破除毛果含笑种子休眠,促进其萌发。 相似文献
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柏木种子活力探讨 总被引:6,自引:1,他引:6
通过对柏木种子活力生化指标的测定,用相关分析、逐步回归和主要成分分析方法,探讨了不同采种期、地形部位、球果大小和种子大小各批种子活力之间的关系。结果表明,种子活力指数可表达种子迅速、整齐萌发的发芽潜力和幼苗生长势,是柏木种子较常规发芽率和其它各生理指标更可靠有效的质量指标。柏木种子生理成熟期较其球果形态成熟期提前10—20天,其后活力显著下降。不同坡位对种子活力影响显著,从坡下部到坡顶,活力显著下降。种子活力与脱氢酶活性和过氧化物酶活性呈显著正相关,与电导率成显著负相关,后者同种子成熟度密切相关。种子4种内含物(蛋白质、还原糖、蔗糖和淀粉)对种子活力,千粒重和幼苗干重影响显著,其中还原糖含量与种子成熟度紧密相关。球果或种子越大,活力越高,二者极显著相关。 相似文献
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种子产业现代化的发展很快,做好种子贮藏工作的一个关键因素是建立环境条件良好的贮藏种子的场所--种子库.本文介绍了国内种子库建设的现状及种子储藏环境,分析了我国种子库房的发展趋势. 相似文献
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The purpose of this study was to investigate the morphology, transmission route of photosynthetic products in the seed stalk of Caragana arborescens Lam. at various stages after flowering and evaluate the role of the seed stalk in seed maturation using scanning electron microscopy. We found that the mature seed stalk mainly consisted of vessels,sclerenchymatous cells and parenchymatous cells. Elongated cells formed a ring at the junction between the seed stalk and seed, and a large hollow was produced by two layers of sclerenchymatous cells in the interior seed, which functions to sustain seed growth. The opening in the center of the ring was closed during an early stage of seed development, and the opening enlarged as the seed matured.There were two routes for material transport, which started from the seed stalk: one from the seed coat to the embryo,and another directly entering the embryo. Vessels, which are abundant in the seed stalk, are the pathway for absorption of nutrients by the seeds. The vessels were densely packed in the seed stalk, and secondary thickening of the cell wall of the vessels was characterized by net thread thickening, while the secondary thickening of the cell wall of the vessels within the seed was characterized by screw thread thickening. The morphological characteristics of the vessels were adaptive to its functions. 相似文献
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川西南山地高山栲种群种子雨和地表种子库研究 总被引:5,自引:0,他引:5
研究川西南山地区两个高山栲低密度种群的种子雨模式、种子雨过程中地表种子库动态和种群的幼苗状况,讨论种子产量、种子存留和种子对成苗的贡献.结果表明:1)种子雨持续时间超过2个月,但种子下落的高峰期存在样地间差异;2)该地区高山栲的种子产量很低,种子雨散落的密度不大(2.3~2.8个·m-2).3)在种子雨过程中,地表种子库各组成的动态不同,霉烂种子和萌发种子为零,完好种子和虫蛀种子有轻微的波动,完好种子的存留密度为0.13个·m-2;和它们相反,地表的壳斗和败育种子存在积累效应.4)动物捕食是地表种子损失的主要原因,两种群分别占91.3%和97.83%,地表种子的存留率仅为8.7%和2.17%.5)研究样地的高山栲种群低的种子生产量、地表种子存留率和幼苗建成困难等3个环节都限制了高山栲种群的实生更新. 相似文献
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Natural variation in seed characteristics of eastern white pine (Pinus strobus L.) trees and its relationship with the size, form, and crown class of parent trees was examined in second-growth, white
pine mixedwood stands in Ontario. Cones were collected prior to and following partial harvesting of two stands during 2 years
of above-average seed production. Fully enlarged seed extracted from mature cones was X-rayed to determine seed yield per
cone, the percentage of sound, partially filled, and empty seed, and the sound seed mass for each tree. Variation in seed
yield per cone, the proportion of sound, partially filled, and empty seed, and seed mass was much greater among individuals
than between stands or seed years. The strength and significance of the relationship of seed mass with sound seed yield differed
with stand and seed year. In uncut stands, seed mass was higher for trees with dominant crown class, larger live crown ratios,
and smaller height to diameter ratios, suggesting tree vigour and microsite quality influence seed mass. Proportion of partially
filled seeds was significantly reduced in both stands in the second year likely due to increased growing degree days during
female gametophyte development. The implications of these results to natural and artificial regeneration of white pine are
discussed. 相似文献