抗生素对火炬松的器官发生植株再生的影响(英文)

本文研究了氨苄青霉素、羧苄青霉素和头孢霉素等3种抗生素对火炬松愈伤组织的生长和分化及不定芽生根的影响。结果表明,头孢霉素最有利于愈伤组织的诱导和生长,羧苄青霉素最有利于芽的分化,氨苄青霉素降低了不定芽的生根频率。所有试验的3种抗生素提高愈伤组织的形成和芽再生,但降低了芽的生根频率。这些结果表明,选择合适的抗生素对优化火炬松遗传转化体系有重要作用。图3表4参25。     

The potential of intercropping as an alternative land use system in temperate North America

The success of many intercropping systems in North America is attributable to the generation of a short term return from an agricultural crop during the early, unprofitable years of a longer term crop that is fruit, nuts or wood. This highly-efficient use of land and related profitability are important not only in the development of intercropping systems per se, but also in other applications which have tremendous potential independent of profitability. For example, intercropping can be effectively used during the establishment phases of hardwood plantations where it is essential to have a high level of weed control, the costs of which are often recovered with the agricultural production. Intercropping can also be used to grow trees rapidly and with a form that can be easily integrated into recreational or park situations, or urban fringe areas. In an urban context, intercropping can be used to grow trees in agricultural areas that are likely to be developed where traditional forestry options are not appropriate and the value of younger, thrifty trees may enhance property values far in excess of the cash value of the wood.     

木质活性炭的光催化再生

根据活性炭吸附机理，利用光催化氧化技术，研究了在主波长253．7nm紫外光辐射下，以锐钛型TiO2及在其表面沉积贵金属Ag的Ag-TiO2为光催化剂，以亚甲基蓝为模型化合物，进行吸附饱和椰壳活性炭的光催化再生。系统研究了再生温度、催化剂活性、再生时间、活性炭粒度、再生次数、pH值对再生效果的影响。结果表明在较高再生温度50℃、较长再生时间72h条件下，再生率达到81％，可以实现木质椰壳活性炭的缓慢光催化再生。     

Ophiostomatoid fungi associated with bark beetles onAbies veitchii in wave-regenerated forests

Relationships between tree mortality and bark beetle infestation onAbies veitchii at the wave-regenerated forest in Mt. Asahi, Okuchichibu area were investigated. Most of the firs with green needles and newly developed current year’s shoots in the dieback zone were heavily infested by bark beetles before the death of the trees. After heavy infestation of beetles, about half of the infested firs died within the year, and the other half died in the next year. When the species composition of bark beetles and associated ophiostomatoid fungi were investigated in Mt. Asahi and also at a typical wave-regenerated forest in Mt. Shimagare, Yatsugatake area,Cryphalus montanus andC. piceae were dominant beetle species for Mt. Asahi and Mt. Shimagare, respectively.Ophiostoma subalpinum andO. europhioides were dominant fungal species at both wave-generated forests. BecauseO. subalpinum was detected more frequently from deeper areas of sapwood thanO. europhioides, it was suggested that the fungal species may accelerate the death of stressed firs in wave-regenerated forests. Contribution No. 169, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba.     

尾叶桉的组织培养及植株再生

研究了以尾叶桉(Eucalyptusurophylla)优树(U6无性系)无菌苗的叶子和茎段作为外植体诱导愈伤组织、丛生芽发生以及植株再生的过程。通过多种生长调节剂不同浓度组合的对比试验,确定了U6快繁体系的最适宜培养条件:(1)愈伤组织诱导培养基:MS 1-2mg/L2,4-D;(2)芽增殖培养基:MS 0.5mg/L6-BA;(3)生根培养基:1/2MS 2.0mg/LNAA。     

厚朴矮林经营技术的初步研究

厚朴伐桩有很强的萌蘖能力，在生长季节采伐也能得到满意的萌芽更新效果，每个伐桩可萌发1－7个萌芽条，7年生厚朴矮林的树干与树枝鲜重达60.2t.hm^-2，平均净生产量为8.6t.hm^-2.a^-1，表明厚朴完全适宜矮林经营，伐桩高度对萌芽条数量，矮林生长影响不大；伐桩萌芽条数量越多，矮林生长越好。     

Effects of a severe typhoon on forest dynamics in a warm-temperate evergreen broad-leaved forest in southwestern Japan

The effects of a typhoon on forest dynamics and the response of major tree species were studied in a warm-temperate evergreen broad-leaved forest in southwestern Japan. The strongest typhoon on record (T9313) passed through this region in 1993. Return periods of typhoons over 30 ms⁻¹ in instantaneous wind velocity and T9313 were estimated to be 2.2 and 104.5 years, respectively. Approximately 10% of all stems suffered some damage from T9313 and annual stem mortality rose from 1.3 to 2.7%. The estimated period that the number of stems would fall below 10% of the initial was four years shorter with T9313-class typhoons than without them. Thus, the disturbance by T9313 was not catastrophic at the site although T9313 was an episodic typhoon. The short-term responses of major tree species to T9313 were classified into four types: 1) blunt-response type with little decrease and recruitment of stems in the DBH ≥ 5 cm class (Distylium racemosum), 2) retreat type with larger decrease than recruitment (e.g. Quercus acuta), 3) sharp-response type with a large decrease and much recruitment (e.g. Cinnamomum japonicum), and 4) advance type with less decrease than recruitment (Eurya japonica). Among the four regeneration types classified by previous studies (climax, light-demanding, subcanopy, and few-sapling), the climax and few-sapling types each showed a specific short-term response, the blunt-response and retreat types, respectively, that explains one aspect of the regeneration strategies of each type. On the other hand, the light-demanding or sub-canopy type showed multiple short-term responses, indicating that each regeneration type contains species with various regeneration strategies. In this paper, I analyzed data from the database that was compiled by the Aya Research Team.     

杉木人工林采伐迹地更新群落结构特征的研究

从杉木人工林科学经营和自然资源管理保护出发，根据定位研究和群落样地调查结果，分析和比较了湖南杉木中心产区会同杉木人工林不同采伐方式迹地上更新群落的组成结构和数量特征．结果表明：迹地群落中共有维管植物85科164属254种，其中乔木、灌木、藤本和草本分别为53种、85种、39种和77种；皆伐和间伐后物种多样性指数高；皆伐8a后迹地群落与皆伐2a后群落相似性较小，而与间伐8a后群落相似性较大；杉木人工林采伐迹地种类成分变更快．提出了合理经营和保护杉木林生态系统多样性和稳定性的措施．     

长序榆天然更新调查研究

对福建省南平市来舟镇东山村残存的珍稀濒危树种长序榆的天然更新状况进行研究,结果表明:长序榆大树虽然生长旺盛,但林下天然更新不良。长序榆果实风播有效距离仅为30m,且由于它是阳性树种,不耐蔽荫,在阳光不足的林下种子难于成苗,幼苗难以成树,天然更新能力弱,这些是它种群数量少,处于濒危状态的主要原因。     

章古台沙区采伐迹地更新造林技术研究

通过多年的生产实践和科学研究，总结出从树种选择、整地、造林、抚育、施肥到病虫害防治等一整套可行的采伐迹地更新造林技术，并提出9种可行的造林设计模式。对于干旱沙区采伐迹地更新造林技术有一定参考意义。