Understanding how environmental adaptation varies among families within a species is critical to adapt forestry activities such as management and breeding to possible future climate change.The present study examined h...Understanding how environmental adaptation varies among families within a species is critical to adapt forestry activities such as management and breeding to possible future climate change.The present study examined home-site advantage and local advantage in growth and basic density of wood in 36 families of Chamaecyparis obtuse(Siebold et Zucc.)Endl.,reciprocally planted at two progeny test sites with differing climatic conditions in Japan.A significant home-site advantage for growth was detected between the lowland and mountainous regions within the Kanto breeding region.In addition,the effects of climate differentials between the selection site of mating parents and the progeny test site on growth and basic density were inves-tigated.As a result,temperature was identified as the most significant climatic factor attributed to local adaptation for growth traits.Elongation and radial growth were adversely influenced when the progeny test site temperature exceeded the provenance temperature by more than 2°C.Therefore,it is crucial to account for temperature differences between the provenance and the planting site to adapt afforestation and forest tree breeding to climate change in the future.展开更多
Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the...Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the early growth and survival of advanced-generation Cryptomeria japonica seedlings compared to conventional stock,under varying planting densities and cultivation methods.A field experiment was conducted over 5 years using containergrown and bare-root seedlings derived from first-and second-generation plus trees,alongside traditional seedlings.The results showed that advanced-generation seedlings exhibited higher growth in tree height,stem diameter,and crown development than traditional seedlings,particularly when planted as container stock.These seedlings also had higher survival rates,likely due to their rapid initial height growth,which reduced the risks of accidental damage during weeding operations.Wider planting intervals increased the risk of man-made injury and seedling mortality,while faster-growing seedlings were more likely to escape from competing vegetation.Our findings highlight the potential of improved seedling stock to enhance early plantation success and reduce management inputs in the critical establishment phase of forestry.展开更多
Pine wilt disease (PWD), which is caused by pine wood nematodes (PWN), is one of the most serious forest diseases worldwide. To clarify the mechanism of resistance to PWD, we compared metabolites from resistant and su...Pine wilt disease (PWD), which is caused by pine wood nematodes (PWN), is one of the most serious forest diseases worldwide. To clarify the mechanism of resistance to PWD, we compared metabolites from resistant and susceptible Japanese black pine (Pinus thunbergii) families after inoculation with PWN. After 2 weeks to 1 month post inoculation, the number of PWN dramatically increased in susceptible plants, but not in resistant plants. At this PWN-proliferation phase, ethyl acetate soluble fractions extracted from PWN-inoculated plants were analyzed by gas chromatogramphy-mass spectrometry (GC-MS). Although most compounds were qualitatively and quantitatively similar between resistant and susceptible plants, resistant plants accumulated 2.0-fold more linoleic acid (LA) than susceptible plants. On the other hand, benzoic acid (BA) was barely detected in resistant plants, but it accumulated in susceptible plants as the number of PWN increased. Susceptible plants contained greater levels of the nematicidal compounds pinosylvin and pinosylvin monomethyl ether, compared with resistant plants. These results suggested that LA is involved in the resistance reaction against PWN-proliferation, and that BA could be a good biomarker for PWD.展开更多
In response to environmental variation, angiosperm trees bend their stems by forming tension wood, which consists of a cellulose-rich G （gelatinous）-Iayer in the walls of fiber cells and generates abnormal tensile s...In response to environmental variation, angiosperm trees bend their stems by forming tension wood, which consists of a cellulose-rich G （gelatinous）-Iayer in the walls of fiber cells and generates abnormal tensile stress in the secondary xylem. We produced transgenic poplar plants overexpressing several endoglycanases to reduce each specific polysaccharide in the cell wall, as the secondary xylem consists of primary and secondary wall layers. When placed horizontally, the basal regions of stems of transgenic poplars overexpressing xyloglucanase alone could not bend upward due to low strain in the tension side of the xylem. In the wild-type plants, xyloglucan was found in the inner surface of G-layers during multiple layering. In situ xyloglucan endotransglucosylase （XET） activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, began at the inner surface layers S1 and S2 and was retained throughout G-layer development, while the incorporation of xyloglucan heptasaccharide （XXXG） for wall loosening occurred in the primary wall of the expanding zone. We propose that the xyloglucan network is reinforced by XET to form a further connection between wall-bound and secreted xyloglucans in order to withstand the tensile stress created within the cellulose G-layer micro fibrils.展开更多
文摘Understanding how environmental adaptation varies among families within a species is critical to adapt forestry activities such as management and breeding to possible future climate change.The present study examined home-site advantage and local advantage in growth and basic density of wood in 36 families of Chamaecyparis obtuse(Siebold et Zucc.)Endl.,reciprocally planted at two progeny test sites with differing climatic conditions in Japan.A significant home-site advantage for growth was detected between the lowland and mountainous regions within the Kanto breeding region.In addition,the effects of climate differentials between the selection site of mating parents and the progeny test site on growth and basic density were inves-tigated.As a result,temperature was identified as the most significant climatic factor attributed to local adaptation for growth traits.Elongation and radial growth were adversely influenced when the progeny test site temperature exceeded the provenance temperature by more than 2°C.Therefore,it is crucial to account for temperature differences between the provenance and the planting site to adapt afforestation and forest tree breeding to climate change in the future.
基金supported by FFPRI FTBC Operational Expense Grants。
文摘Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the early growth and survival of advanced-generation Cryptomeria japonica seedlings compared to conventional stock,under varying planting densities and cultivation methods.A field experiment was conducted over 5 years using containergrown and bare-root seedlings derived from first-and second-generation plus trees,alongside traditional seedlings.The results showed that advanced-generation seedlings exhibited higher growth in tree height,stem diameter,and crown development than traditional seedlings,particularly when planted as container stock.These seedlings also had higher survival rates,likely due to their rapid initial height growth,which reduced the risks of accidental damage during weeding operations.Wider planting intervals increased the risk of man-made injury and seedling mortality,while faster-growing seedlings were more likely to escape from competing vegetation.Our findings highlight the potential of improved seedling stock to enhance early plantation success and reduce management inputs in the critical establishment phase of forestry.
文摘Pine wilt disease (PWD), which is caused by pine wood nematodes (PWN), is one of the most serious forest diseases worldwide. To clarify the mechanism of resistance to PWD, we compared metabolites from resistant and susceptible Japanese black pine (Pinus thunbergii) families after inoculation with PWN. After 2 weeks to 1 month post inoculation, the number of PWN dramatically increased in susceptible plants, but not in resistant plants. At this PWN-proliferation phase, ethyl acetate soluble fractions extracted from PWN-inoculated plants were analyzed by gas chromatogramphy-mass spectrometry (GC-MS). Although most compounds were qualitatively and quantitatively similar between resistant and susceptible plants, resistant plants accumulated 2.0-fold more linoleic acid (LA) than susceptible plants. On the other hand, benzoic acid (BA) was barely detected in resistant plants, but it accumulated in susceptible plants as the number of PWN increased. Susceptible plants contained greater levels of the nematicidal compounds pinosylvin and pinosylvin monomethyl ether, compared with resistant plants. These results suggested that LA is involved in the resistance reaction against PWN-proliferation, and that BA could be a good biomarker for PWD.
文摘In response to environmental variation, angiosperm trees bend their stems by forming tension wood, which consists of a cellulose-rich G （gelatinous）-Iayer in the walls of fiber cells and generates abnormal tensile stress in the secondary xylem. We produced transgenic poplar plants overexpressing several endoglycanases to reduce each specific polysaccharide in the cell wall, as the secondary xylem consists of primary and secondary wall layers. When placed horizontally, the basal regions of stems of transgenic poplars overexpressing xyloglucanase alone could not bend upward due to low strain in the tension side of the xylem. In the wild-type plants, xyloglucan was found in the inner surface of G-layers during multiple layering. In situ xyloglucan endotransglucosylase （XET） activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, began at the inner surface layers S1 and S2 and was retained throughout G-layer development, while the incorporation of xyloglucan heptasaccharide （XXXG） for wall loosening occurred in the primary wall of the expanding zone. We propose that the xyloglucan network is reinforced by XET to form a further connection between wall-bound and secreted xyloglucans in order to withstand the tensile stress created within the cellulose G-layer micro fibrils.
