Environmental factors play vital roles in successful plantation and cultivation of tree seedlings.This study focuses on problems associated with reforestation under extreme continental climatic conditions.The objectiv...Environmental factors play vital roles in successful plantation and cultivation of tree seedlings.This study focuses on problems associated with reforestation under extreme continental climatic conditions.The objectives were to assess relative seedling performance(survival and growth)with respect to plantation age,and to analyze the influence of specific climatic factors during the early stages of Scots pine(Pinus sylvestris L.)plantations.The study was carried out in reforested areas of the Tujyin Nars region of northern Mongolia on six Scots pine plantations ranging from 5 to 10 years.In each of the six plantations,five 900 m^2 permanent sample plots were established and survival rates and growth performance measured annually over 7 years.Results show high variation in survival among the plantations(p<0.001,F=29.7).Seedling survival in the first year corresponded directly to the number of dry days in May.However,survival rate appeared to stabilize after the second year.The insignificant variation of height categories throughout the observation period indicated low competition among individuals.Two linear mixed-effect models show that height and radial growth were best explained by relative air humidity,which we consider to be a reliable indicator of site-specific water availability.Insufficient amounts and uneven distribution of rainfall pose a major threat during the first year of plantation establishment.Humidity and water availability are decisive factors for a successful seedling plantation.This highlights the impact of drought on forest plantations in northern Mongolia and the importance of developing climate resilient reforestation strategies.展开更多
The leopard moth （Zeuzera pyrina L）, is a cossid whose larvae bore into twigs, branches and trunks of various woody species, weakening and killing trees or shrubs. Recently it caused serious losses of apple trees in...The leopard moth （Zeuzera pyrina L）, is a cossid whose larvae bore into twigs, branches and trunks of various woody species, weakening and killing trees or shrubs. Recently it caused serious losses of apple trees in Syria. The flight dynamics of Z. pyrina was monitored by pheromone traps （first time in Syria） compared to light trap device. This study was carried out in Damascus countryside, Qunaytirah and Sweida provinces during 2007-2008. Results indicated that the flight of moths during 2007 started in early June in Damascus countryside and Sweida provinces. The highest number of caught adults （the highest peak） was concentrated in mid July in Sweida province, whereas in Damascus countryside province there were a high peak in mid June and a small peak in early July. On the other hand, flight of moths during 2008 started in mid-May in Damascus countryside province while in Qunaytirah province started in early June. The highest number of caught adults （the highest peak） was concentrated in late July in Damascus countryside, whereas in Qunaytirah province there were small peaks in mid June and mid July. Experiments conducted to evaluate capturing efficiency of different types of traps （pheromone traps and light trap） demonstrated that there was significantly high difference within the trap devices, wherein Capta trap got the best results and caught more males than the others.展开更多
The area cultivated with sugarcane in Brazil is expanding, and increasingly using legumes cover crop in new deployed areas and in those which were reformed. Long-term trials were carried out in Piracicaba, Sao Paulo, ...The area cultivated with sugarcane in Brazil is expanding, and increasingly using legumes cover crop in new deployed areas and in those which were reformed. Long-term trials were carried out in Piracicaba, Sao Paulo, Brazil, to evaluate the effect of leguminous green manure on the natural infestation of Diatraea saccharalis (Fabr.) during five cropping cycles of sugarcane “IAC 87-3396”. This study was carried out from October 1999 to October 2005 in Piracicaba, Sao Paulo, Brazil, at coordinates 22°42''S and 47°38''W, 560 m above sea level, in soil classified as Typic Paleudult. Green manure crops were assigned to five treatments: peanuts (Arachis hypogaea L.) (cultivar “IAC-Tatu” and “IAC-Caiapó”), sunn hemp (Crotalaria juncea L.) (cultivar “IAC 1”) and velvet-bean [Mucuna aterrima (Piper & Tracy) Holland] (cultivar “common”). A treatment without any green manure or weed was used as the control. The previous sugarcane crop was destroyed and the soil was prepared in a conventional way (using plow and harrow) before the leguminous crops were sowed. Thirty days after the sowing, weeds were removed and, 120 days later, the crops were cut and its biomass was deposited on the soil surface without incorporation. Experimental plots comprised five rows of sugarcane, each one measuring 10 m long and spaced 1.40 m apart. The sugarcane was harvested 18 months after biomass deposit, on October 25th, 2001 and its stalks were collected at intervals of approximately 12 months in: 07/09/2002, 08/01/2003, 11/07/2004 and 10/06/2005. At harvest, the masses were determined from a sample of sugarcane, cut from three rows (2 m long) in the center of the plot. The losses caused by the sugarcane borer were estimated by the intensity of the infestation by randomly observing and collecting sugarcane stems from each plot. A great reduction in the number of stalks and in the yield was noted proportionally to the intensity of the infestation of the borer in the sugarcane crop grown after the velvet-bean. The sugarcane-velvet-bean rotation should be regarded considering the intensity of sugarcane borer infestation. No influence of the other green manure crops was observed on the intensity of the infestations. However, the harvest seasons of the sugarcane seemed to influence the borer infestation.展开更多
Pinus massoniana L. is one of the important trees for afforestation in South China. The efficient system of plant regeneration from mature zygotic embryos and seedlings of masson pine was established in this study. Th...Pinus massoniana L. is one of the important trees for afforestation in South China. The efficient system of plant regeneration from mature zygotic embryos and seedlings of masson pine was established in this study. The influences of basal media, hormones and methods for buds induction, shoots elongation and rooting were studied. The results indicate that DCR medium with 0.5 mg/L BA and 0.05 mg/L IBA shows the highest differentiation rate of adventitious buds. Induction and multiplication of axillary buds take aseptic seedlings as explants. KT has better effect than BA on the axillary buds induction. The best axillary buds induction medium is DCR medium supplemented with 1 mg/L KT and 0.2 mg/L IBA. After culturing on GD medium with 0.1 mg/L BA and 0.2 mg/L IBA for elongation,the buds were transferred on the 1/2 GD medium with 2 mg/L IBA and 0.05 mg/L BA for adventitious roots induction. Paraffin slice indicates that the adventitious buds developed from the meristematic tissue of cotyledonary epicuticula.展开更多
基金supported by the Partnerships for Enhanced Engagement in Research(PEER)Science Cycle 2 Grant#296’Building research and teaching capacity to aid climate change and natural resource management at the National University of Mongolia(NUM)’
文摘Environmental factors play vital roles in successful plantation and cultivation of tree seedlings.This study focuses on problems associated with reforestation under extreme continental climatic conditions.The objectives were to assess relative seedling performance(survival and growth)with respect to plantation age,and to analyze the influence of specific climatic factors during the early stages of Scots pine(Pinus sylvestris L.)plantations.The study was carried out in reforested areas of the Tujyin Nars region of northern Mongolia on six Scots pine plantations ranging from 5 to 10 years.In each of the six plantations,five 900 m^2 permanent sample plots were established and survival rates and growth performance measured annually over 7 years.Results show high variation in survival among the plantations(p<0.001,F=29.7).Seedling survival in the first year corresponded directly to the number of dry days in May.However,survival rate appeared to stabilize after the second year.The insignificant variation of height categories throughout the observation period indicated low competition among individuals.Two linear mixed-effect models show that height and radial growth were best explained by relative air humidity,which we consider to be a reliable indicator of site-specific water availability.Insufficient amounts and uneven distribution of rainfall pose a major threat during the first year of plantation establishment.Humidity and water availability are decisive factors for a successful seedling plantation.This highlights the impact of drought on forest plantations in northern Mongolia and the importance of developing climate resilient reforestation strategies.
文摘The leopard moth （Zeuzera pyrina L）, is a cossid whose larvae bore into twigs, branches and trunks of various woody species, weakening and killing trees or shrubs. Recently it caused serious losses of apple trees in Syria. The flight dynamics of Z. pyrina was monitored by pheromone traps （first time in Syria） compared to light trap device. This study was carried out in Damascus countryside, Qunaytirah and Sweida provinces during 2007-2008. Results indicated that the flight of moths during 2007 started in early June in Damascus countryside and Sweida provinces. The highest number of caught adults （the highest peak） was concentrated in mid July in Sweida province, whereas in Damascus countryside province there were a high peak in mid June and a small peak in early July. On the other hand, flight of moths during 2008 started in mid-May in Damascus countryside province while in Qunaytirah province started in early June. The highest number of caught adults （the highest peak） was concentrated in late July in Damascus countryside, whereas in Qunaytirah province there were small peaks in mid June and mid July. Experiments conducted to evaluate capturing efficiency of different types of traps （pheromone traps and light trap） demonstrated that there was significantly high difference within the trap devices, wherein Capta trap got the best results and caught more males than the others.
文摘The area cultivated with sugarcane in Brazil is expanding, and increasingly using legumes cover crop in new deployed areas and in those which were reformed. Long-term trials were carried out in Piracicaba, Sao Paulo, Brazil, to evaluate the effect of leguminous green manure on the natural infestation of Diatraea saccharalis (Fabr.) during five cropping cycles of sugarcane “IAC 87-3396”. This study was carried out from October 1999 to October 2005 in Piracicaba, Sao Paulo, Brazil, at coordinates 22°42''S and 47°38''W, 560 m above sea level, in soil classified as Typic Paleudult. Green manure crops were assigned to five treatments: peanuts (Arachis hypogaea L.) (cultivar “IAC-Tatu” and “IAC-Caiapó”), sunn hemp (Crotalaria juncea L.) (cultivar “IAC 1”) and velvet-bean [Mucuna aterrima (Piper & Tracy) Holland] (cultivar “common”). A treatment without any green manure or weed was used as the control. The previous sugarcane crop was destroyed and the soil was prepared in a conventional way (using plow and harrow) before the leguminous crops were sowed. Thirty days after the sowing, weeds were removed and, 120 days later, the crops were cut and its biomass was deposited on the soil surface without incorporation. Experimental plots comprised five rows of sugarcane, each one measuring 10 m long and spaced 1.40 m apart. The sugarcane was harvested 18 months after biomass deposit, on October 25th, 2001 and its stalks were collected at intervals of approximately 12 months in: 07/09/2002, 08/01/2003, 11/07/2004 and 10/06/2005. At harvest, the masses were determined from a sample of sugarcane, cut from three rows (2 m long) in the center of the plot. The losses caused by the sugarcane borer were estimated by the intensity of the infestation by randomly observing and collecting sugarcane stems from each plot. A great reduction in the number of stalks and in the yield was noted proportionally to the intensity of the infestation of the borer in the sugarcane crop grown after the velvet-bean. The sugarcane-velvet-bean rotation should be regarded considering the intensity of sugarcane borer infestation. No influence of the other green manure crops was observed on the intensity of the infestations. However, the harvest seasons of the sugarcane seemed to influence the borer infestation.
文摘Pinus massoniana L. is one of the important trees for afforestation in South China. The efficient system of plant regeneration from mature zygotic embryos and seedlings of masson pine was established in this study. The influences of basal media, hormones and methods for buds induction, shoots elongation and rooting were studied. The results indicate that DCR medium with 0.5 mg/L BA and 0.05 mg/L IBA shows the highest differentiation rate of adventitious buds. Induction and multiplication of axillary buds take aseptic seedlings as explants. KT has better effect than BA on the axillary buds induction. The best axillary buds induction medium is DCR medium supplemented with 1 mg/L KT and 0.2 mg/L IBA. After culturing on GD medium with 0.1 mg/L BA and 0.2 mg/L IBA for elongation,the buds were transferred on the 1/2 GD medium with 2 mg/L IBA and 0.05 mg/L BA for adventitious roots induction. Paraffin slice indicates that the adventitious buds developed from the meristematic tissue of cotyledonary epicuticula.
