Báo cáo lâm nghiêp: "Multiplication végétative in vitro de quelques espèces d’ormes" doc

... cas des ormes une prolifération intense de cals est induite par les cytokinines, tant au niveau de l’introduction des explants primaires in vitro que dans la phase de multiplication. ... intensive de certains clones (établissement de pied-mères in vitro) . Toutefois, ces méthodes pourraient devenir plus performantes dès la phase d’intro- d...

Ngày tải lên: 09/08/2014, 06:22

... Several cytokinins, including zeatin and zeatin riboside, were detected in seedling leaves. Discussion and Conclusion These results demonstrate the presence of cytokinins in leaves ... increased cytokinin activity in leaves of C. jambhiri. Colonization by G. fasciculatum and G. mosseae resulted in a significant increase in seedling leaf cytokinin...

Ngày tải lên: 09/08/2014, 04:20

... were planted in the soil from the decomposing stand and compared with both yellowing and green seedlings planted in the soil from the beech stand (Table 8). Phenomena of decline in two spruce ... again, primarily in those variants of the pot experi- ment in which we compared yellowing spruce seed- lings planted in the soil with intensive impact of spruce litter and green spru...

Ngày tải lên: 07/08/2014, 03:22

... 13–38. PRIMAULT B., 1995. Etude de différentes possibilités de depouillement de données climatologiques: De lévolution de la température et des précipitations de 1864 à 1990 à cinqu stations météorologique. ... warming resulting from the increase in the volume of carbon dioxide in the atmosphere, particularly over the last decades (F, J 1996). Following...

Ngày tải lên: 07/08/2014, 03:22

... arboricides for “chemical thinning”. Relative to the conventional mechanical thinning, this technique is far less time and resource demanding (K 1968). In the past, arboricides were ... erefore, thinning measures can be more intensive and can be repeated at longer time intervals (K 1968; J, V 1966). Dead standing trees maintain higher relative air hu- midity in...

Ngày tải lên: 07/08/2014, 03:22

... main factors determining the effect of a driving unit on soil are density of soil in the rut and its depth, which depend on the number of passages in the same track. Investigations included ... without us- ing engineering structures and drainage and have rather large longitudinal inclines, which in most cases does not allow using them for the passage of wheeled machinery skidders a...

Ngày tải lên: 07/08/2014, 03:22

... 80.312 70.912 46.638 Stand density index ECC 137.3 115.7 84.5 50.5 388.0 Stand density index BCC 62.3 57.8 38.4 158.5 ECC – end of cutting cycle; BCC – beginning of cutting cycle; BA – basal area; ... allocation as a guide in stocking control in multiaged, mixed-conifer forests in southern Finland. Forestry, 74: 171–185. PEARSON G.A., 1942. Improvement selection cutting in ponde...

Ngày tải lên: 07/08/2014, 04:20

... is is to be achieved by determining the quanti- ty of available N at the beginning of growing sea- son; evaluating potentially available N by diff erent methods; determining nitrogen absorbed by ... clear-cutting disrupts the existing balance of the soil organic matter con- tent. By clear-cutting, stopping N uptake by trees and decreasing total deposition, N availability in the soil is i...

Ngày tải lên: 07/08/2014, 10:21

... (independent factors – T and months, covariate – altitude of seed origin). e monthly germination indicators were compared to annual average (using absolute differences and relative seasonal indexes). ... fluctuation of ger- mination should be considered in laboratory testing Month 1 2 3 4 5 6 7 8 9 10 11 12 Mean index of GC 1.04 1.02 1.00 0.98 0.96 0.94 Fig. 5. Average indexes of germina...

Ngày tải lên: 07/08/2014, 10:21

... 1,400 Füldner index Stage growth Stage optimum Stage breakdown Altitudinal category Fig. 2. e values of Füldner in- dex in individual altitudinal cat- egories and developmental stages of the virgin forest ... Concerning the spatial distribution of the trees in the virgin forest, no tendency of their clustering in connection with altitude was found in the zones below 1,460 m. e...

Ngày tải lên: 07/08/2014, 10:22