首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2篇
  免费   0篇
林业   1篇
农作物   1篇
  2008年   1篇
  1982年   1篇
排序方式: 共有2条查询结果,搜索用时 15 毫秒
1
1.
Influence of mycorrhizae and fertilization on Acer pseudoplatanus seedlings . A greenhouse experi-ment compared growth and mineral nutrition of Acer pseudoplatanus seedlings on two soils with different fertilizations and with different endomycorrhization treatments. A strain of Glomus mosseae and a mycorrhizal complex from an A. pseudoplatanus stand prove to be much more growth efficient than the natural inoculum of the soils, mainly by improving phosphorus nutrition. These effects are additive to those of fertilization. This last result suggests that controlled mycorrhization can be of great practical interest even on rich soils.  相似文献   
2.
The study of the gill fishes of 176 Oreochromis niloticus (L.) was undertaken in the dam of Loumbila (Burkina Faso), in order to obtain the first information on the dynamics of population of the Monogeneans parasites in a population of wild hosts. These data are essential in the search for means to avoid the enormous losses that often occur in intensive pisciculture. This analysis revealed the presence of five species of Monogeneans (Cichlidogyrus tilapiae, Cichlidogyrus halli, Cichlidogyrus thurstonae, Cichlidogyrus rognoni and Scutogyrus longicornis). On the levels of the recorded infestations, these species taken individually probably do not control the population of Oreochromis niloticus. In the dam of Loumbila, the fluctuations of parasitic abundances are neither seasonal nor cyclic. The size either does not have an influence on parasitism. However, the sex effect was noted with C. halli, the females thus were more infested than the males. O. niloticus is parasitized all the year, because the recruitment of these organisms, although relatively weak, is continuous; this logically results in their accumulation in this fish.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号