植物单倍体育种及其在林木育种中的应用

单倍体植物是进行植物遗传分析及开展育种工作的理想材料, 具有能有效控制杂交后代性状分离、缩短育种周期等优点, 在林木育种中具有广阔的前景。文中概述人工诱导单倍体的方式, 重点综述目前最常用的花药离体培养获得单倍体植株的方法, 探讨花药离体培养在林木育种应用中存在的问题, 展望林木单倍体育种的意义及应用前景。     

欧洲的杨树育种

本文根据国际杨树委员会第35届执委会会议文献,综述了欧洲杨树育种的近况,包括育种的理想模式、杂交方式、杂交技术、先进的育种程序、新技术的应用和几个值得注意的问题。     

杨树抗寒育种研究进展

对国内外杨树抗寒育种的研究从天然杂种选择、人工杂交育种、基因工程育种方面进行了综述,提出杨树抗寒育种存在的问题并进行了展望。     

杨树基因工程育种研究进展

该文主要对国内外杨树基因工程育种在抗虫、抗病、抗除草剂、抗旱、抗逆、降低木质素及雄性不育等方面的研究进展进行了综述,详细介绍了各个方面近些年来的研究成果,并对杨树基因工程育种中存在的问题及发展对策进行了讨论。     

辽宁省杨树育种现状及发展趋势

根据大量的文献资料，对辽宁省的杨树育种现状及今后发展方向作了扼要的阐述和分析，我省的杨树育种前期从５０年代末至８０年代初期，分为速生育种，抗盐育种，单倍体育种，选择自然要交种和远缘杂交育种５个方面；后期从８０年代初期开始，利用美洲黑杨的优良基因，培育２出辽宁杨，辽河杨，盖杨，大大提高了树树生产力水平及抗性。并提出了今后杨树育种的发展趋势，不应单纯追求速生，而对抗盐，抗旱，抗瘠、抗寒、抗病虫等质量性     

我国杨树育种的研究进展及对策

简要介绍了我国杨树育种研究的发展历程、进展状况及取得的成就,分析了制约我国杨树良种选育的主要因素,提出了今后我国杨树育种应以社会需求为导向,制定长短目标结合的系统育种计划,大力丰富并创新杨树种质,重视亲本选择,加强生态育种和低耗高效型品种选育,在不断革新的育种理论和技术基础上,探索建立现代杨树育种体系,从而促使我国杨树育种获得新突破。     

影响冬季杨树造林成活率因素调查

近年来,冬季是中原地区植树造林及林业生产的主要季节,因此必须认真把握造林时间和方法.实践表明,尽量缩短起苗到栽植的时间,选择气温在5～15 ℃之间的秋末冬初时节植树最适宜,新栽幼树在冬季可以愈合生根,保证成活.杨树的栽植方法要注意深栽、浇水、踏实、不能晃动.     

杨树育种研究进展

从杨树种质资源、引种、杂交育种、多倍体育种、分子育种等方面概述了我国及湖北省杨树育种的发展历程,并对目前中国及湖北省杨树育种存在的主要问题及解决对策进行了讨论。     

Haploid breeding ofpopulus

After 14 year’s growth observation on the plant growth, it was found that obvious segregation appeared among the haploid pollen plants obtained from anther culture ofPopulus Xiaohei T.S. Hwany ex C. Wang et Tung in vitro. By vegetative propagation, 19 clones were selected and field contrast test was carried out. Statistical analysis result showed a significant difference in volume production. They are superior clones which could be selected from among the pollen plants for utilization. A haploid breeding procedure is suggested in the paper. This study was supported by the National Natural Science Foundation of China     

毛白杨离体繁殖技术

毛白杨属杨柳科杨属，是我国特有树种，树干通直，高大，适应性强，生长快，是用材林和城乡绿化的优良树种，其优株的无性系苗木，生长速度比普通毛白杨快15％～20％，经济价值更高。但用常规无性繁殖时，如扦插、压条等，很难生根，加之繁殖材料有限，不仅用材多，费工费时，而且成活率低，繁殖系数不大，很难在短期内繁殖大量苗木。试管快繁对于毛白杨来说，无论在理论上和生产实践上均具有重要的意义。目前，毛白杨的试管快繁技术已在造林育苗的生产实践中推广应用。我们用植物组织培养法进行毛白杨的快速繁殖，在短时间内收到了良好的效果。     

美国山核桃的品种适应性及其影响因素

介绍了美国山核桃的天然分布区气候特征、对环境条件的要求、抗寒性、抗病性、抗虫性及其影响因素，以及美国山核桃引种栽培区划等方面的内容，以期为科学引种和生产应用提供参考。     

Socioeconomic factors influencing global paper and paperboard demand

To clarify the socioeconomic factors influencing global paper and paperboard demand, a panel data analysis was conducted covering the period 1961–2014. This study used paper and paperboard demand as the dependent variable, and a country’s economic level, Internet usage rate, plastic packaging demand, and time trend as the explanatory variables. An inverse U-shaped quadratic relationship, such as an environmental Kuznets curve, was found between economic level and paper and paperboard demand, which saturates and begins to decline as economic level increases. The economic level representing the turning point differs significantly with the use, ranging from around 37,000 US$/person for newsprint paper to around 66,000 US$/person for printing and writing paper. For both newsprint paper and printing and writing paper, demand declines owing to the spread of the Internet as the economic level rises, although this reductive effect is greater for printing and writing paper than for newsprint paper. A substitution relationship is not found between wrapping paper and corrugated cardboard on the one hand and plastic packaging on the other hand as the economic level becomes higher.     

Some factors influencing the increment of forests

It is humbling to read the paper by R.N. Aldrich-Blake (1927)because he deduced many truths that we have since confirmed,and he deduced them with the most subtle of arguments. His articlecould still be used if one were to start building a computermodel to capture the physiologi cal processes of tree growth.His ideas alone would provide a suitable framework for modellingand most of the internal and external factors affecting assimilationand respiration would be included. The model would lack a modernunderstanding of biochemistry, particularly of photo synthesisand the role of nutrients, and Aldrich-Blake did not considerthe important problem of allocating assimilated carbon to thegrowth of different parts of the tree. Our ideas on allocationare now changing and there is emerging evidence for the roleof plant signals in allocation which, in turn, affects the incrementin timber volume.     

Environmental factors influencing outbreak of Scleroderris lagerbergii Gremmen

In this contribution some important factors as shading, humidity, frost and soil influencing the outbreak of an epidemic by Scleroderris lagerbergii under Austrian conditions are discussed in detail.     

试析影响路基压实的因素

分析影响路基压实的因素：土质、含水量、压实功能和地基强度。     

杨木单板的压缩与树脂浸渍处理对胶合板性能的影响

采用正交试验设计方法,研究了杨木单板压缩率、胶液浓度、树脂浸渍时间和热压温度四个因素对杨木胶合板性能的影响。结果表明:杨木单板的压缩与树脂浸渍处理可以显著提高杨木胶合板的力学性能。当杨木单板压缩为35%、胶液浓度90%、树脂浸渍时间2h、热压温度150℃时,杨木胶合板的MOE、MOR和胶合强度分别高出国家标准127%、212%和77%。