共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
3.
我国胡桃属(Juglans L. )种质资源与核桃(Juglans regia L. )育种 总被引:12,自引:0,他引:12
我国是胡桃属的分布中心,原产5种,已引进5种。本文提出将我国核桃的栽培实生群划分为新疆、华北山地、秦巴山地、西藏高地四个地理生态型;并对它们的分布区域及主要生态特征以及各个地理生态型内的重要实生类群作了简要论述。 相似文献
4.
Henning Lemche 《Journal of pest science》1941,17(6):68-70
Ohne Zusammenfassung
Mit 2 Abbildungen 相似文献
5.
6.
7.
木兰科含笑属常绿乔木,高15 ̄20m,芽被浓密的棕黄色绢毛。枝、叶两面、叶柄均无毛。叶坚革质,有光泽,叶背粉绿色,长8~14cm,宽4~7cm;叶柄长1~3cm,无托叶痕。花腋生,白色,杯状,花被9枚。聚合果长4 ̄5cm;种子宽椭圆形,长0.8cm;花期3 ̄4月,果期8 ̄9月。产海南,海拔200~1500m;稍耐阴,成年树喜光,在广州栽培生长良好。湖南浏阳县有花农引种,生长良好,能越冬。对城市环境适应性强。耐最低温度约-6℃,pH值4.5~6.5。石碌含笑树形优美,叶泽光亮,是优良的观赏树种。主要用于盆栽,摆放于大厅、会议厅、入口处;亦可在公园、住宅区、花坛、街道配置… 相似文献
8.
9.
10.
Pertti Pulkkinen Lu-Min Vaario Leena Koivuranta Niina Stenvall 《European Journal of Forest Research》2013,132(5-6):791-800
This study aimed to understand the interaction between temperature and genotype in terms of the effect on early seedling development of European aspen (Populus tremula) and various F2-aspen hybrids. We evaluated the response of 16 different European aspen and F2-hybrid families on seed germination, survival rate and seedling height in one- and two-family trials under three different temperature regimes. In one-family trials, higher germination and higher survival rates were observed in higher temperature (C1700), leading to taller seedlings. European aspen × hybrid aspen individuals (Asp × Hyb) had a higher survival rate and taller seedlings than Asp, Hyb × Asp or Hyb × Hyb individuals. The difference between Asp × Hyb and Hyb × Asp was pronounced. Both growth conditions and genotype (i.e., hybrid cross) had strong effects on germination, survival rate and height of European aspen and F2-hybrid seedlings. However, the interaction of genotype and growth conditions also had a significant influence on survival rate and seedling height, but not on germination. Two-family trials involving European aspen and F2-hybrids led to significant negative effects on germination and survival rate and also facilitation effects on seedling height. Similarly, genotype had strong effects on germination and survival rate. Different genotypes and traits affected survival rate and seedling height differently in different growth conditions. These differences were more pronounced in the warmest environment, i.e., 1,700 degree days. We conclude that introgression between F2-hybrids and local European aspen is likely in the current climate, and any warming will likely favor certain F2-hybrids, especially the most probable types (P. tremula × (P. tremula × P. tremuloides)). 相似文献
11.
蔷薇科红果树属,常绿小乔木,高5 ̄8m.,枝近无毛。叶革质,长3 ̄8cm,两面无毛,或仅中脉有微毛,叶边缘通常波浪状而不平整。花萼、花瓣各5枚。花期5-6月,梨果红色,果期8-12月,成熟期11-12月。主要分布于陕西、湖北、湖南、江西(武功山),海拔800 ̄1700m;喜光,耐干旱,但在润湿、肥沃 相似文献
12.
13.
ZHANG Xiao-fen CHEN Min ZHANG Bin-yu LUO You-qing HOU Ying-jie SU Xiao-hua Key Laboratory for Silviculture Conservation Ministry of Education Beijing Forestry University Beijing P. R. China Key Laboratory of Tree Breeding Cultivation State Forestry Administration Research Institute of Forestry Chinese Academy of Forestry Beijing P. R. China. 《中国林学(英文版)》2009,(3)
Laboratory feeding experiments with the poplar aphid, Chaitophorus populeti (Panzer), feeding on transgenic poplar (P. alba × P. glandulosa) varieties C13-5 and C013-5, were carried out to study the effect of transgenic poplar on the ladybird Harmonia axyridis (Pallas). The mortality and development time of the immature stages, the eclosion rate and body mass of H. axyridis were measured. The results indicated that C. populeti feeding on different varieties of transgenic plants had no statistically signific... 相似文献
14.
ZHANG Xiao-fen CHEN Min ZHANG Bin-yu LUO You-qing HOU Ying-jie SU Xiao-hua 《中国林学(英文版)》2009,11(3):164-167
Laboratory feeding experiments with the poplar aphid, Chaitophorus populeti (Panzer), feeding on transgenic poplar (P. alba × P. glandulosa) varieties C13-5 and C013-5, were carried out to study the effect of transgenic poplar on the ladybird Harmonia axyridis (Pallas). The mortality and development time of the immature stages, the eclosion rate and body mass of H. axyridis were measured. The results indicated that C. populeti feeding on different varieties of transgenic plants had no statistically significant effect on the mortality of H. axyridis larvae. The development time of larval and pupal stages were not significantly different between the two transgenic poplars
and a non-transgenic poplar. Furthermore, the body mass and eclosion rate did not show any difference between the H. axyridis feeding on aphids reared on transgenic plants and those from non-transgenic plants. It is suggested that transgenic plants
have no deleterious effect on the predatory ladybird. 相似文献
15.
《Scandinavian Journal of Forest Research》2012,27(1-4):449-463
Three test series were planted on sites selected for their contrasting properties to study the genotype × site interaction. Various clones of Salix alba (8 clones in the 1980 series), S. dasyclados (8 clones in 1982 series) and S. viminalis (6, 9, 13 clones in the various series) were included. Growth capacity, survival and infection by rust fungi were analysed. Interspecific variation was seen at some of the sites in the 1982 series but it was pronounced in the 1980 series where 5. viminalis outgrew 5. alba at all sites. Intraspecific variation could be seen for growth capacity, survival and rust resistance. A genotype × site interaction was detected for all variables studied. Some of the interaction, especially at the species level, can be explained by the variation in susceptibility to rust fungi and preference for soil types. In the breeding work with Salix the genotype × site interaction must be considered. 相似文献
16.
17.
矮沙樱桃(Prunus pumila var. depressa)是分布于北美洲的固沙灌木树种。在全面了解矮沙樱桃的生物学特性及原产地气候与立地条件的基础上,分析了此树种的生态价值与经济价值,其推广应用对丰富三北地区固沙树种的多样性,将林业的生态效益与经济效益进行有机结合,实现三北工程的可持续发展具有一定的积极作用。 相似文献
18.
19.