Blada I.,Forest Research and Management Institute of Bucharest
Annals of Forest Research | Year: 2011
In order to get ornamental trees for landscaping, Colorado blue spuce (Picea pungens Engelm. var. glauca Regel) scions were grafted on Norway spruce (Picea abies (L.) Karst.) rootstocks. An original double-side-veneer grafting method was applied in five experimental or basic variants. The plastic tapes and the ecological Ceraltin® wax developed by the Research and Development of Bio-stimulators (CCDB) BIOS Cluj were tested. In addition, two controls in which the classic raffia and the traditional hot wax and the classic side-veneer-grafting method were used. The obtained results, expressed in percents, were transformed in arcsin square root of percent values, and then a two-way analysis of variance (ANOVA) was used. Highly significant (p < 0.001) statistical differences were found between all grafting variants, including controls. The Duncan test proved that original double-side-veneer grafting method and the new developed materials, i.e. plastic tapes and the ecological Ceraltin® wax have contributed in getting a better grafting success compared to the controls. Thus, the double-side-veneer grafting method and the two grafting materials are highly recommended to be used in getting grafted Colorado blue spuce ornamental trees.
Tenow O.,Swedish University of Agricultural Sciences |
Nilssen A.C.,University of Tromsø |
Bylund H.,Swedish University of Agricultural Sciences |
Pettersson R.,Uppsala University |
And 18 more authors.
Journal of Animal Ecology | Year: 2013
We show that the population ecology of the 9- to 10-year cyclic, broadleaf-defoliating winter moth (Operophtera brumata) and other early-season geometrids cannot be fully understood on a local scale unless population behaviour is known on a European scale. Qualitative and quantitative data on O. brumata outbreaks were obtained from published sources and previously unpublished material provided by authors of this article. Data cover six decades from the 1950s to the first decade of twenty-first century and most European countries, giving new information fundamental for the understanding of the population ecology of O. brumata. Analyses on epicentral, regional and continental scales show that in each decade, a wave of O. brumata outbreaks travelled across Europe. On average, the waves moved unidirectionally ESE-WNW, that is, toward the Scandes and the Atlantic. When one wave reached the Atlantic coast after 9-10 years, the next one started in East Europe to travel the same c. 3000 km distance. The average wave speed and wavelength was 330 km year-1 and 3135 km, respectively, the high speed being incongruous with sedentary geometrid populations. A mapping of the wave of the 1990s revealed that this wave travelled in a straight E-W direction. It therefore passed the Scandes diagonally first in the north on its way westward. Within the frame of the Scandes, this caused the illusion that the wave moved N-S. In analogy, outbreaks described previously as moving S-N or occurring contemporaneously along the Scandes were probably the result of continental-scale waves meeting the Scandes obliquely from the south or in parallel. In the steppe zone of eastern-most and south-east Europe, outbreaks of the winter moth did not participate in the waves. Here, broadleaved stands are small and widely separated. This makes the zone hostile to short-distance dispersal between O. brumata subpopulations and prevents synchronization within meta-populations. We hypothesize that hostile boundary models, involving reciprocal host-herbivore-enemy reactions at the transition between the steppe and the broadleaved forest zones, offer the best explanation to the origin of outbreak waves. These results have theoretical and practical implications and indicate that multidisciplinary, continentally coordinated studies are essential for an understanding of the spatio-temporal behaviour of cyclic animal populations. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.
Blada I.,Forest Research and Management Institute of Bucharest |
Panea T.,Research Development Center for Bio stimulators
Annals of Forest Research | Year: 2012
The achieved results concerning the grafting silver-fir - Abies concolor [(Gord. & Glend.) Lindl] scions on white-fir (Abies alba Mill.) rootstocks are reporting in this article. The double-side-veneer grafting method and the plastic tape and the ecological Ceraltin ® wax were applied in four experimental variants. The side-veneer-grafting method and the classic materials, such as raffia and the hot wax were used at the two controls involved in this experiment. The grafting success expressed in percents, were transformed in arcsin square root of percent values, and a two-way analysis of variance was performed. Highly significant (p < 0.001) statistical differences were found between grafting variants, including controls. The Duncan Multiple Range Test showed that the four experimental grafting variants were highly significantly (p > 0.01) better than the two controls. The grafting success of the best experimental variant has surpassed the two controls by 129 and 153%, respectively. Consequently, the double-side-veneer grafting method, the new developed plastic tape and the ecological Ceraltin ® wax have contributed to this grafting success owing to which they are recommended to be used for grafting silver-fir ornamental trees.