Báo cáo lâm nghiệp: "Micropropagation of hybrid walnut trees (Juglans nigra x Juglans regia) through culture and multiplication of embryos" ppt

... Micropropagation of hybrid walnut trees (Juglans nigra x Juglans regia) through culture and multiplication of embryos D. Cornu C. Jay-Allemand bres Forestiers, INRA, ... France Introduction Walnuts are very valuable trees for nuts and wood production, but we see a reduc- tion in the number of logs available for veneer. Although Pers...

Ngày tải lên: 09/08/2014, 04:20

... (1968) Nutrient requirements of suspension cultures of soybean root cells. Exp. Cell Res. 50, 151-158 Gongalves A.N. (1983) Reversion to juvenility and cloning of Eucalyptus urophylla ... end of 30 d, maximum shoot pro- duction occurred at 0.5 mg ’ I- 1 BAP and 0.01 mg ’ I- 1 IBA (Fig. 1). In this treatment, an average of 10 shoots develope...

Ngày tải lên: 09/08/2014, 04:20

... other sources of interannual variation of ring width index are not included in the model. Past- and cur- rent-year temperature and precipitation are examples of such variables that can explain a large ... fir trees were then selected in the vicinity of the plot at a distance of at least 25 m. These trees were harvested and sample discs (3-cm thick) were cut at 0.15, 0.60,...

Ngày tải lên: 08/08/2014, 00:21

... error of 0.15, and 19 trees for an error of 0.10; for P. nigra at least 6 trees are required to keep the error under 0.20 with a probability of 95%, 11 trees for an error of 0.15, and 26 trees for ... area of trees larger than the subject tree and thinned during the next 10-year period (m 2 ·ha –1 ), G is stand basal area (m 2 ·ha –1 ), and GI is the stand growth...

Ngày tải lên: 08/08/2014, 01:21

... Forest and Landscape Research Institute. JENSEN F.S., 1993. Landscape Managers’ and Politicians’ Perception of the Forest and Landscape Preferences of the Population. Forest and Landscape ... increases. Wood production and the use of wood products imply a largely neutral production and consumption cycle with regard to emissions of carbon dioxide. Expanding the forest...

Ngày tải lên: 07/08/2014, 03:22

... potas- sium, sodium and cobalt. RESULTS AND DISCUSSION We performed chemical analyses of the bark of damaged and undamaged trees and we analyzed the changes in the content of nutrients and elements ... development and occurrence of hoofed game were investigated by J et al. (1999). Trees with damaged bark usually suffer from the penetration of fungi spores...

Ngày tải lên: 07/08/2014, 04:20

... values of pH that might be related to an exposure of the area to high air pollution in the past. e complex of studied stands belongs to the Abieto-Fagetum forest type. Two neighbouring stands ... 36.5 cm, age of about 80 years. Stocking of the stand was 0.8. Mean tree height of beech in the main canopy was ca 27.5 m, mean dbh 33.0 cm, age of nearly 90 years. Stocking of...

Ngày tải lên: 07/08/2014, 10:22

... part of France [2, 31]. The stand is included in a continuous forest of 700 ha, consisting mostly of naturally regenerated mixed stands of Q. petraea and Q. robur. The sampled stand covers approx- imately ... total of 286 standing trees. It consists of three ecological zones: a small valley, a plateau and a regular intermediate slope. The plateau is covered by a well drained...

Ngày tải lên: 07/08/2014, 16:20

... predicted and observed mean values; Test 2) an ANOVA that compared the following two models: y = x and y = ax + b, with y = observed site index and x = predicted site index, to detect if site index prediction ... vegetation and site productivity in mature stands of Pinus sylvestris in southern Finland. Using a comparable method, the first ordination axis of a detrended corresp...

Ngày tải lên: 08/08/2014, 00:22

... stand, the distribution of trees of different ages and sizes was very irregular. The selective harvest removed most of the sparser patches of large trees and left denser patches of undersize trees. ... choice of hydraulic excavation tech- niques restricted our excavation area to that which was within reach of the hose, which was limited by the power of the pump and...

Ngày tải lên: 08/08/2014, 01:21