厚朴种子园植株密度与母树生长关系初步研究

在厚朴(Magnolia officinalis)种子园建设中,通过不同的厚朴母树植株密度对比试验表明,厚朴母树植株密度与母树生长关系密切,厚朴母树植株密度直接影响着母树的胸径生长、树高生长和树冠生长,影响着厚朴母树的结果率和挂果量,从而影响着种子园的结果量。     

选好母树 适时采种

良种出壮苗,壮苗树速生。良种是培育壮苗的物质基础,在林木种子的生产过程中,选择优良母树,适时采集优良种子是培育壮苗,植树造林,建立可持续的森林生态系统,发展林业经济的一个重要环节。1、选择优良的母树俗话说:"母肥子壮"。母树的性状、生长、发育都与种子质量有着密切关系,但不是所有的母树都会结出优良的种子,所以采种首先要选择好母树,选取质量特别好的优树,作为采种母树。从优良母树上采集的种子不但具有优良的     

人工长白落叶松优良单株母树选择技术

文章简述了长白落叶松优良母树选择的意义,优良母树选择、分级的标准、方法。     

修剪促进油松无性系种子园母树开花效应研究

为增加油松无性系种子园母树雌雄球花数量,对母树进行了截顶和修剪试验。结果表明,适宜的截顶和修剪,对增加油松母树雌雄花数量有显著作用。     

信息窗

△施肥对沙地樟子松母树开花结实的作用。给沙地樟子松母树林施肥,是提高母树开花结实的一种有效措施。据试验,施草炭和混合氮、磷、钾肥料,能增加沙地樟子松母树雌花的数量,可比对照提高39.2～79.5％,10年左右的母树,每株追施硫酸铵200克、磷肥300克为宜;钾肥对母树开花结实作用不大。母树施肥事先应该进行土壤调查和肥力分析,以便确定合理的施肥种类及数量。 (据《辽宁林业科技》) △果树缺铁症打针可以治愈。果树缺铁黄化失绿是一项难治的生理病害。山西省农科院朱文勇     

桉树扦插育苗中的几个主要环节

桉树扦插育苗，采用由原母株采集外殖体进行茎尖繁殖的组培菌作母树，短期内可获得大量与原母株同质的采穗母树，并优于采用优良单株伐桩萌条扦插成苗建立的采穗母树群．结合数年实践经验，对母树插穗、生根剂、环境因子、扦插季节、病虫害等几个主要环节作了介绍。     

修剪促进红松无性系种子园母树开花效应研究

为增加红松无性系种子园母树雌雄花开花数量,对母树进行了树冠修剪和切根修剪试验。结果表明,适宜强度的树冠修剪和切根修剪,对增加红松母树雌雄花开花数量有显著作用。     

油松采种母树林结实因子分析及种子产量预测

通过对采种母树生长量、结实因子分析,得出母树单株果树由南、西、西北、东坡向依次降低;单株种子产量与母树生长量成正相关,与当年小球果树、翌年成熟大球果树成极显著正相关的结论。并利用其进行种子产量预测,建立预测模型,预测精度在95%以上。     

修剪强度对马尾松成年种子园母树的影响

以16年生的马尾松嫁接种子园成年母树为研究对象,采用保留不同轮枝数(A:保留第1轮枝;B:保留2轮枝;C:保留3轮枝;D:保留4轮枝;以不做修剪作为对照(CK))的修剪方式开展母树矮化试验,观测其对母树生长和开花的影响。结果表明:保留轮枝数越少越能改善母树光照条件,有效降低母树主干高度,增强母树抽稍能力,增加雌配子体数量,方便管理。不同处理后除雄配子体数量低于对照,其它指标均优于对照,以处理A的效果最佳。     

保水剂对麻疯树采穗圃母树穗条产量的影响

为了科学有效的开发利用攀西地区麻疯树资源,以287株麻疯树良种母树为材料,分别设置保水剂S、L、M和(1)共4个处理,以筛选产穗量最高的剂型。在母树萌发穗条数量上保水剂L、M处理与其它处理有显著的差异性;在母树生长量上保水剂L、(1)、M、L处理与对照有显著的差异性。施用保水剂M、L、(1)和S的母树平均萌发穗条数量分别比对照提高133.2%、110.1%、105.3%和103.0%。施用保水剂M、L、(1)和S的母树平均新梢生长量分别比对照提高6.5 cm、10.5 cm、8.9 cm和10.9 cm;保水剂处理母树的有效穗条数依次为M(1)LS。     

杉木种子园球果病虫害监测研究

经调查统计,杉木种子园健康果、发育不良果、病害果、虫害果、病虫兼有果比例分别为55.1%、3.4%、8.4%、9.0%、24.1%,各无性系之间球果产量、不健康果比例,百果重、千粒重、出粒率、发芽率都达到极显著差异水平。球果病虫危害率与球果产量、球果出籽率、种子发芽率之间存在极显著负相关,病虫危害是种子园种子产量下降的主要原因之一。用1%波尔多液或500倍敌克松溶液喷洒种子园接株,效果十分理想,病虫危害可以控制在10.0%以内。     

Seed supply and the regeneration potential for plantations and shrubland in southern China

Assessing the characteristics of seed supply will be vital to better understand the dynamics of forest regeneration. In this study, we surveyed the aboveground vegetation, the seed rain, the seed bank, and natural seedling emergence in four typical 24-year-old plantations (eucalyptus, mixed-native, mixed-legume, and mixed-conifer) and a naturally successioned shrubland in southern China. The dominant species in the understory were similar among the five plant communities. The seed rain and the seed bank were dominated by shrubs and herbs but indigenous tree species were rare. Species that were common to all five-plant communities represented a great proportion of the seeds in the seed rain and seed bank. The seed rain consisted mostly of seeds derived from the local plant community. Seed abundance was greater in the seed bank than in the seed rain, and species richness was greater in the seed bank and in the corresponding plant community than in the seed rain. Species composition similarity between the seed rain, the seed bank, and the aboveground vegetation was low, because the seed rain contained much fewer species, and the seed bank and aboveground vegetation contained many different species, respectively. These findings indicate that both the seed rain and the seed bank play important roles in providing seeds for plant recruitment in the understory, but the seed bank contributes more than the current seed rain to the diversity of recruited plants. The current plant community has little impact on the qualitative composition of the seed rain and seed bank. Based on these data, it appears that succession to the desired zonal, mature forest community is unlikely to result from seeds in the seed rain or seed bank. Lack of seed availability of desired zonal mature forest species is the main bottleneck currently limiting succession in the plantations. Reintroduction of late-successional species could facilitate the desired succession.     

湖南省杉木种子园结实现状及发展对策

从分析湖南现有杉木初级、1.5代、2代种子园结实量现状入手,分析了不同世代的种子园结实量低的原因.初级种子园主要是林龄大,树体高大,本身结实量少,加上树体大,可采种子非常少;1.5代种子园,都闭度大,树枝枯死,造成结实量少;2代种子园管理粗放,种子产量不高.根据多年对种子园结实量研究,提出了提高种子园结实量的主要技术措...     

苦槠种子形态性状的地理变异分析

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.     

柏木种子活力探讨

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。     

Variation in cone and seed characters in blue pine (Pinus wallichiana) across natural distribution in western Himalayas

We analyzed 17 seed sources (seed stands) of Pinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states (Uttarakhand and Himachal Pradesh) of India. The significant variations were observed in cone weight, cone length, cone width, seed length, seed width, seed weight, seed germination, radicle length, and plumule length among different seed sources of the species. Significant positive correlation between seed weight, cone weight and cone width showed that seed weight in the species depend more on the cone size. Seed germination was also positively correlated with seed weight, cone weight and radicle length in the study. The estimates of variability with regard to genetic parameters for seed weight, seed germination, cone length, cone width, cone weight showed wide range of variation in the study. Seed weight showed high heritability values coupled with maximum genetic gain. Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i.e. genotypic and environmental interaction. The study suggests that the seed weight should be given the top priority for the further improvement of this species.     

兴安落叶松母树林丰产型结构的研究

通过对兴安落叶松母树林丰产型结构、林木级结构与种子产量、偏雌偏雄母树性状及标准、母树林结构与种子产量和质量相关问题的研究，结果表明，30－40a兴安落叶松母树林丰产型结构是：Ⅰ级木占75％；Ⅱ级木占25％；偏雌母树占50％－60％。偏雄母树占10％，中间类型占40％左右。     

Natural Variation in Seed Characteristics of Eastern White Pine (Pinus strobus L.)

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.     

红松无性系种子园与实生种子园种实性状观测

建立红松无性系种子园和实生种子园的实践证明:嫁接母树的结实株数、结实率、公顷产种量、种子千粒重等9项种实性状均优于实生母树,关键种实性状指标结实率、公顷产种量、出种率、种子千粒重、出仁率分别是实生母树的3.67倍、2.74倍、1.16倍、1.02倍和1.12倍.     

Tree Seed Procurement–Diffusion Pathways in Wonogiri and Ponorogo, Java

Forty-two percent of the land area in the neighbouring districts (kapubatens) of Wonogiri, Central Java and Ponorogo in East Java is covered with secondary forests of naturalized exotic tree species that are common components of governmental land rehabilitation programs. The seed suppliers operating in the Wonogiri–Ponorogo area represent only 9% of the suppliers in Indonesia yet they account for 80–90% of the national tree seed supply capacity. Wonogiri–Ponorogo suppliers procure and sell 1,510 tons of seed annually. About 24% of this (362 tons) is exchanged between suppliers, 1,148 tons are sold to customers across Indonesia, and less than 1 ton is exported. About 72% of the seed sold (826 tons) is collected in the Wonogiri–Ponorogo area, the remainder originating in Sumatra, Madura and Nusa Tenggara. In Wonogiri–Ponorogo, tree seeds are collected by farmers on contract with seed assemblers or seed companies. Assemblers link farmer collectors with seed companies and middlemen, who sell seed to customers. Government agencies purchase 75% of the seed. Cover crop species, Gmelina arborea, Tectona grandis and Leucaena leucocephala account for the 85% of the total seed sold. The sheer volume of seed collected in Wonogiri–Ponorogo assures that it comes from a large number of unrelated trees over widely dispersed locations. However, research results indicate individual farmers collect seed from a limited number of adjacent trees. Experience indicates simple seed collection guidelines help farmers improve their seed collection practices and the genetic quality of seed collected. A commitment to seed quality by all agents involved in the seed trade and customers is required to make such guidelines functional and acceptable. Seed procurement and diffusion generate significant income for all seed agents. As the dominant agents who facilitate most of the activities and inputs required to move seed through the pathway from forests to customers, seed companies receive the most financial benefits. Farmer seed collectors are the most numerous agents in the seed pathway, with an estimated 22,500 farmers involved in seed collection activities annually. Farmer families living near seed companies earn additional income by processing seed.