Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early g...Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones, P. balsamifera x trichocarpa （PBT） and P. maximowiczii x balsamifera （PMB）, one improved family of Norway spruce （Picea glauca （PA）） and one improved family of white spruce （Picea abies （PG）） growing under different spacings in monocultures and mixed plots. The plantations were established in 2003 in Abitibi-Témiscamingue, Quebec, Canada, in a split plot design with spacing as the whole plot factor （1 × 1 m, 3 × 3 m and 5 × 5 m） and mixture treatments as subplot factor （pure： PBT, PMB, PA and PG, and 1：1 mixture PBT：PA, PBT：PG, PMB：PA and PMB：PG）. Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones, but not for the 5 × 5 m spacing because of the relatively young age of the plantations. Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m, while their height growth increased, resulting in similar aboveground biomass per tree across treatments. Because of the large size differences between spruces and poplars, aboveground biomass in the mixed plantings was generally less than that in pure poplar plots. Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PMB was greater in mixed plots than in monocultures, while leaf nitrogen concentration of clone PBT was similar among mixture treatments. Because of its faster growth rate and greater soil resources demands, clone PMB was the only one showing an increase in leaf N with increased spacing between trees. Fine roots density was greater for both hybrid poplars than spruces. The vertical distribution of fine roots was insensitive to mixture treatment.展开更多
The new emerging stems and buds of poplar 110(Populus deltoids×P.maximowiczii cv ’Eridano’) were used as explants and incubated on MS media supplemented with various hormone combinations.Once the successive and...The new emerging stems and buds of poplar 110(Populus deltoids×P.maximowiczii cv ’Eridano’) were used as explants and incubated on MS media supplemented with various hormone combinations.Once the successive and rooting plants were obtained through selection of cultural medium formula,leaves and internodals were excised from tubed-culture planlets and induced to form regenerated plants.The result showed MS+6-BA 0.5 mg·L-1+NAA 0.1 mg·L-1+TDZ 0.02 mg·L-1 was beneficial for leaves to inducing adventitious buds;The proper medium for using internodals as explants was MS+6-BA 0.3 mg·L-1+NAA 0.05 mg·L-1+TDZ 0.02 mg·L-1;while the medium of MS+6-BA 0.3 mg·L-1+NAA 0.1 mg·L-1 was proper to culturing the stronger tubed-planlets.The optimum medium for producing roots was 1/2MS+IBA 0.5 mg·L-1.The effect of different incising mode and growth state of leaves and internodals on inducing adventitious was discussed.In vitro vegetative propagation and plant rooting were optimized to establish the high-efficient tissue culture reproduction system of poplar 110,which make it possible for tree breeding and genetic transformation of this species.展开更多
基金funded by Canada Economic Development,Quebec’s Ministry of Natural Resources and Fauna (MRNF)the Natural Sciences and Engineering Research Council of Canada through a Collaborative and Research Development grant to ADthe Program on Energy Research and Development of Natural Resources Canada
文摘Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones, P. balsamifera x trichocarpa （PBT） and P. maximowiczii x balsamifera （PMB）, one improved family of Norway spruce （Picea glauca （PA）） and one improved family of white spruce （Picea abies （PG）） growing under different spacings in monocultures and mixed plots. The plantations were established in 2003 in Abitibi-Témiscamingue, Quebec, Canada, in a split plot design with spacing as the whole plot factor （1 × 1 m, 3 × 3 m and 5 × 5 m） and mixture treatments as subplot factor （pure： PBT, PMB, PA and PG, and 1：1 mixture PBT：PA, PBT：PG, PMB：PA and PMB：PG）. Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones, but not for the 5 × 5 m spacing because of the relatively young age of the plantations. Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m, while their height growth increased, resulting in similar aboveground biomass per tree across treatments. Because of the large size differences between spruces and poplars, aboveground biomass in the mixed plantings was generally less than that in pure poplar plots. Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PMB was greater in mixed plots than in monocultures, while leaf nitrogen concentration of clone PBT was similar among mixture treatments. Because of its faster growth rate and greater soil resources demands, clone PMB was the only one showing an increase in leaf N with increased spacing between trees. Fine roots density was greater for both hybrid poplars than spruces. The vertical distribution of fine roots was insensitive to mixture treatment.
文摘The new emerging stems and buds of poplar 110(Populus deltoids×P.maximowiczii cv ’Eridano’) were used as explants and incubated on MS media supplemented with various hormone combinations.Once the successive and rooting plants were obtained through selection of cultural medium formula,leaves and internodals were excised from tubed-culture planlets and induced to form regenerated plants.The result showed MS+6-BA 0.5 mg·L-1+NAA 0.1 mg·L-1+TDZ 0.02 mg·L-1 was beneficial for leaves to inducing adventitious buds;The proper medium for using internodals as explants was MS+6-BA 0.3 mg·L-1+NAA 0.05 mg·L-1+TDZ 0.02 mg·L-1;while the medium of MS+6-BA 0.3 mg·L-1+NAA 0.1 mg·L-1 was proper to culturing the stronger tubed-planlets.The optimum medium for producing roots was 1/2MS+IBA 0.5 mg·L-1.The effect of different incising mode and growth state of leaves and internodals on inducing adventitious was discussed.In vitro vegetative propagation and plant rooting were optimized to establish the high-efficient tissue culture reproduction system of poplar 110,which make it possible for tree breeding and genetic transformation of this species.
