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研究证明，沙棘种源苗期生长量、生长进程及种子形态和播种品质等存在显著的地理变异；生长性状变异呈以等效纬度和海拔为负相关地理变异模式；种子性状变异以经向为主，纬向为辅的双向变异，表现为高经度、等效纬度偏低的种源种子长宽比小，千粒重大，发芽率高，种子品质优良；沙棘地理变异体现了由干到湿，由冷到暖种源呈正向渐变的规律；根据苗期综合表现，将沙棘种源划分３个种群：西北华北种群、新疆种群和西藏种群，其中西北华 相似文献
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直干桉(Eucalyptus maienii)原产澳洲,五十年代初期引入云南,属外来的珍贵树种,具有生长迅速,适应性强等优点,由于引入的时间短,数量少,种子价格昂贵,难以大面积推广,其次,该树种质量性状方面的遗传品质存在不同程度的退化,如直干桉不直等。为满足大理州日益增长的直干桉种子需求,也 相似文献
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史密斯桉在陆良的引种试验 总被引：1，自引：0，他引：1
雷彩惠 《云南林业调查规划设计》2001,26(1):60-62
1995年从澳大利亚引进史密斯桉7个种源，试验点设在陆良县野鸭塘林场，对照为云南直干桉和蓝桉商品混合种子，从苗期和幼对期的生长情况分析，认为15064，18284，18676，19688等4个种源表现较好，可以在珠防工程中采用。 相似文献
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１９９５年从澳大利亚引进史密斯桉７个种源，试验点设在陆良县野鸭塘林场，对照为云南直干桉和蓝桉商品混合种子，从苗期和幼树期的生长情况分析，认为以１５０６４．１８２８４，１８６７６，１９６８８等４个种源表现效好，可以在珠防工程中采用 相似文献
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樟子松种子变异与种子品质关系的研究 总被引：3，自引：0，他引：3
樟子松（ＰｉｎｕｓＳｙｌｖｅｓｔｒｉｓｖａｒｍｏｎｇｏｌｉｃａ）是一个变异水平较高的树种，不仅其冠型、干型、皮包型、分枝角侧枝粗普遍存在变异，而且球果大小、颜色和球果表面鳞盾形状以及种子的颜色。大小也发生变异，本文着重研究变异和种子品质的关系，并分析种子变异的原因。 相似文献
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试验研究证明:(1)沙棘种源苗期生长量、生长进程及种子形态和播种品质等存在显著的地理变异;(2)生长性状变异里以等效纬度和海拔为负相关地理变异模式;(3)种子性状变异以经向为主,纬度为辅的双向变异,表现为高经度、等效纬度偏低的种源种子长宽比小,千粒重大,发芽率高,种子品质优良;(4)沙棘地理变异体现了由干到湿,由冷到暖,种源呈正向渐变的规律;(5)根据苗期综合表现,将沙棘种源划分三个种群为:西北华北种群、新疆种群和西藏种群。其中西北华北种群为优良种群。 相似文献
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史密斯桉引种栽培试验 总被引：1，自引：0，他引：1
从澳大利亚引进史密斯桉原产地的7个种源，以保山市本地生长量较好的直干桉和蓝桉作对照，在保山市隆阳区国营林场长岭岗林区进行了引种栽培试验。苗期到5年生幼树的生长情况表明，史密斯桉在云南保山市适生，幼林树高、胸径、冠幅生长量均达到或超过当地的直干桉和蓝桉，出油率均比直干桉和蓝桉高。引种的7个种源中，尤以18688、18681、18682表现最好，有较好的发展前途，可进一步推广。 相似文献
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To provide an objective approach for comparing various planting methods likely to differ in cost, seedling performance, and cost efficiency, loblolly pine (Pinus taeda L.) seedlings were dug-hole or slit planted with either straight, deformed, or pruned taproots, and planting rate (seconds per seedling) and three-year survival and growth of seedlings were measured. The per-hectare cost of dug-hole planting seedlings to ensure straight taproots ($273) was over five times that of slit planting seedlings with intentionally deformed or pruned taproots ($50). Although third-year pine survival did not differ significantly among treatments (74% to 87%), yield index was 58% higher for seedlings dug-hole planted with straight taproots (1152 dm3 stem volume/ha) versus that for seedlings slit planted with deformed or pruned taproots (730 dm3/ha). Third-year cost efficiency (yield index ÷ planting cost) of slit planted seedlings with deformed or pruned taproots (11.7 dm3/$) was over three times that of dug-hole planted seedlings with straight taproots (3.5 dm3/$). These short-term results suggest that the higher values of yield index resulting from straight-root planting do not justify its considerably greater cost. 相似文献
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Interactions between scarification treatments and seedling types of Norway spruce were examined at two different locations in southern Sweden. The scarification treatments were not scarified control, mounding and soil inversion and the seedling types were a 10 week-old containerized seedling (mini seedling), a 2 year-old containerized seedling and a 2 year-old hybrid seedling, grown as a containerized seedling the first year and as a bare-root seedling the second year. Site preparation intensity had a greater effect on the mini seedlings. The results indicated that mini seedlings established faster in the soil inversion treatment compared to the larger seedling types. At the same seedling age, the mini seedlings had faster or similar growth rate as the containerized and the hybrid seedlings regardless of scarification treatment. Although mini seedlings grew as well as or even better than larger seedlings if they were successfully established, they were more sensitive to their planting environment and proper handling was critical. Problems with frost heaving and competing vegetation have to be taken into consideration when choosing site preparation method and seedling type. 相似文献
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Quantifying root system quality of nursery seedlings and relationship to outplanting performance 总被引：2，自引：2，他引：2
With over 1.5 billion forest tree seedlings produced annually in the USA, seedling quality assessment is critical to ensure reforestation success. While height and root-collar diameter are the most common traits evaluated during seedling quality assessment, above-ground morphology is not always an accurate predictor of performance after outplanting. Root system morphology and physiological status may provide a more accurate indication of seedling potential. However, relatively few studies have attempted to quantitatively assess root system quality in relation to outplanting success. Large root volume, high root fibrosity, and an increased number of first-order lateral roots have shown some correlation to improved field performance. Physiological seedling quality assessment is commonly practiced through evaluation of root growth potential. Other tests, such as root electrolyte leakage, have also shown some potential as measures of seedling physiological quality. This review identifies current methods of assessing seedling root system quality and discusses potential shortcomings of these methods. An increased understanding of the suitability of current tests, coupled with the development of new tests and multiple parameter relationships, may foster the development of species and site-specific targets for seedling root system quality assessment. The production of seedlings with root systems that meet high morphological and physiological standards better enables seedlings to rapidly establish and thrive upon outplanting. 相似文献
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云南高氏甜龙竹苗木质量分级及造林效果 总被引：1，自引：1，他引：0
为保障高氏甜龙竹（商品名）苗木质量,提高造林效果,在昆明市嵩明县、富民县,保山市昌宁县,玉溪市元江县开展了播种育苗和扦插育苗试验,以苗高、地径为分级指标研究了高氏甜龙竹1年生苗的分级标准。结果显示,不同地区苗木的分级标准具有一定差异,其中富民县和元江县对Ⅰ级苗的要求较高,富民县Ⅰ级播种苗要求苗高≥8.31 m、地径≥4.63 cm,元江县Ⅰ级扦插苗要求苗高≥6.55 m、地径≥3.67 cm。高氏甜龙竹不同育苗方式,其苗木生长状况存在差异,表现为播种苗的各项生长指标均好于扦插苗,特别是根系的生长状况和每丛株数,播种苗的平均根系数量、根系总质量、每丛株数分别是扦插苗的7.07倍、7.13倍和6.69倍,表明播种苗以后的生长潜力更大。不同等级的高氏甜龙竹苗木的造林效果,无论是播种苗还是扦插苗,Ⅰ级苗的造林成活率均达到100%,Ⅱ级苗的造林成活率也可达到95%以上,Ⅲ级苗的造林成活率均低于82%。 相似文献
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为研究轻基质与黄心土两种不同基质育苗效果,选用木荷（Schima superba）、桃花心木
（Swietenia mahagoni）、闽楠（Phoebe bournei）、红锥（Castanopsis hystrix）、红桂木（Artocarpus nitidus）
5 个主要造林树种,开展轻基质与黄心土育苗对比试验。结果表明：轻基质苗保存率总体比黄心土苗高 1
个百分点;轻基质苗高、径生长量明显优于黄心土苗,平均苗高高出 16.3 cm,平均地径高出 0.3 cm;生
长节律比较显示：芽苗移栽后,轻基质苗比黄心土苗恢复快,高、径生长快,且苗木整齐均匀,轻基质
苗高和地径的变异系数分别比黄心土苗低 1 个和 5 个百分点。因此认为轻基质育出的种苗质量高。 相似文献
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对辽宁省凤城市国有凤山林场苗圃不同苗龄红松苗木生长量和山地造林3龄、4龄和5龄红松苗木生长量和造林成活率进行研究,结果表明:随红松苗龄的增加,苗高、地径、主根长和大于1mm侧根条数明显增加,苗龄越长,生长量越大;山地造林采用4龄红松苗比采用3龄和5龄苗造林成活率高。 相似文献
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水曲柳(Fraxinus mandshurica Rupr.)是东北地区三大珍贵硬阔叶用材树种之一,也是东北地区的重要造林树种。研究了不同育苗密度对水曲柳床播苗木生长的影响,结果表明,当密度达到100株/m^2时,为最优育苗密度,其苗高、地径、主根长、侧根数、生物量最优,有利于优质壮苗的培育。 相似文献
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针叶树是芬兰、瑞典、挪威、美国、加拿大等欧美国家主要的商品林树种。容器苗是针叶树重要的育苗类型。与裸根苗比较,容器苗具有育苗周期更短、造林季节可延长、苗木适应性更广、苗木质量更一致的优点。因此,容器育苗成为精准林业发展的必然趋势。为了借鉴欧美容器育苗的技术方法,提高我国容器苗的质量,为我国针叶树容器苗发展提供参考,文中主要从4个方面综述了欧美国家检测与提高苗木质量的方法,即列举了针叶树常用的苗木质量检测指标,总结了育苗容器与育苗基质的改良进展,介绍了养分、水分、光照与温度等培养条件的优化手段,简要概述了容器苗病虫害防控的进展,提出了我国相关树种容器苗生产的启示与借鉴。 相似文献