Báo cáo lâm nghiệp: "Sexual reproduction in Populus II Information molecules of the pollen grain" pptx

... attractive tool for overcoming inter- specific incompatibility in poplars. Sexual reproduction in Populus II. Information molecules of the pollen grain M. Gaget 1 M. Villar 2 C. ... semi-tected exine (Figs. 1 and 2). The presence of a great amount of osmiophilic components in the pollen coat is observed within the arcades of the ex...

Ngày tải lên: 09/08/2014, 04:20

... allowed the visualization of 15 stigmatic and pollinic glycoproteins. Differences were observed, according to the type of cross: one distinct glycoprotein increases only in the ... pollinic enzymes involved in pollen tube metabo- lism, such as ¡3-galactosidase. Its activity could be the final result of a series of inter- actions started by...

Ngày tải lên: 09/08/2014, 04:20

... be during the spring and part of the autumn. During and after the appearance of shoots, the plant discards the old leaves, once the translocation of the nutrients has taken place [24]. In this ... and another in November with 5.44 g m −2 .In 1997 the acorn fall took place gradually from September to January of the following year with a collection in October...

Ngày tải lên: 07/08/2014, 16:20

... mass loss rather than the mean in interpreting the results improves the reproducibility of the results, and reduces the impact of singular results that can- not be explained [49]. The median mass ... thickness: the thinner the sapwood, the greater the tree diameter and the lower the decay resistance. 3.Colour is related to height and radial position in the tr...

Ngày tải lên: 08/08/2014, 01:21

... compared the seedlings planted in the soil with intensive impact of spruce litter and the seedlings planted in the sub- strate from the beech stand (without the in uence of acid litter). In the ... and mainly of aluminium. e low content of potassium also indicates the insufficiency of water regimen both in soil and in individual spruce trees. e general...

Ngày tải lên: 07/08/2014, 03:22

... evidence of the loss in the fir volume and the increase in beech volume was collected. – However, the increasing share of beech, accompa - nied by a decrease in the share of fir, is typical of the ... that the total rise in temperature in the immediate vicinity of the Carpathians and Tatras in the course of the current warming process is typical...

Ngày tải lên: 07/08/2014, 03:22

... (I +II) , – in the last three needle age classes (I +II+ III), – in all needle age classes of the top part of a tree that died (defoliation of the tree top). Since we followed the needle age classes during ... that the arboricide appli- cation in the growing season was more reliable than in the period of dormancy. In this study, the period of application w...

Ngày tải lên: 07/08/2014, 03:22

... especially during the construction of skidding tracks by a bulldozer. For example, in the mountains, if the area of skidding tracks is 8% of the total cutting area, the volume of soil damaged ... sampling. Before the beginning of investigations the radius of turns, lengths of linear plots, weight and geometrical parameters of a tractor were determined. Sa...

Ngày tải lên: 07/08/2014, 03:22

... ratio of the number of trees in one diameter class to the number of trees in the next larger diameter class. e “q” is therefore sensitive to the slope of the distribution and also the range of ... rejection of the even-aged plantation forest model by much of the public, particularly in more developed regions. is is increasing the interest in mult...

Ngày tải lên: 07/08/2014, 04:20

... subtraction of the initial content of available mineral N (for the anaerobic incubation of NH 4 + -N content); N initial ‒ initial content of available mineral N (for the anaerobic incubation of NH 4 + -N ...  e intensity of miner- alization (IM) was calculated from the following formula: IM = total initialmin – N NN (2) where: N min ‒ quantity of mineralized N...

Ngày tải lên: 07/08/2014, 10:21