Forest ecosystems worldwide can be affected by extreme climatic events.Trees respond to these occurrences in multidimensional ways,involving various mechanisms,to deal with the effects and restore the forests to their...Forest ecosystems worldwide can be affected by extreme climatic events.Trees respond to these occurrences in multidimensional ways,involving various mechanisms,to deal with the effects and restore the forests to their optimal state.Such abilities are known as resilience.Tree ring analysis can be used to evaluate drought resilience.Analysis of dendrophenotypes,together with genetic studies,has become an essential tool for identifying drought resilient genotypes.This study aimed to determine the dendrogenomic resilience mechanisms in the fragmented,isolated,rare endemic Mexican species Picea martinezii and P.mexicana by analysis of annual rings and the associations with SNP markers identified by genotyping by sequencing(GBS).Increment cores and needles for GBS for resilience analysis were collected from P.martinezii trees in three populations,and from P.mexicana trees in two populations.The results show that fundamental dendrogenomic mechanisms were associated with drought resilience in P.martinezii and P.mexicana.PC1 in PCA for five outlier SNPs was linked to annual tracheid width variations in P.martinezii caused by severe drought events in 1962,1989,1998 and 2011.These five outlier SNPs were located in genes coding the proteins reticulon-like protein B22,pollen-specific leucine-rich repeat extension,ornithine decarboxylase like,LisH/CRA/RING-U-box domains-containing protein and proline transporter 2-like isoform X1,which are important in the dry stress tolerance metabolism involved in the resilience response in plants.The discovery of genetic markers associated with drought resilience highlights the importance of preserving genetic diversity.展开更多
Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to...Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to ongoing debate in this field.Moreover,gaps remain in understanding the climatic mechanisms driving increased tree growth variability,particularly for species simultaneously limited by multiple climate factors.In this study,we assessed the temporal trends in variability of Picea purpurea radial growth and its linkage with growth-climate sensitivity utilizing dendrochronological methods.Our results revealed a significant increase in P.purpurea radial growth variability from 1960 to 2020,as indicated by continuous rises in the standard deviation,coefficient of variation,and mean sensitivity of tree-ring width indices.The increased frequency of extreme growth declines further supported this finding.Furthermore,moisture condition in July was identified as a key limiting factor of P.purpurea growth.Notably,the strengthening relationship between tree-ring width indices and vapor pressure deficit(VPD)suggests that the moisture sensitivity for P.purpurea growth has increased over the period 1960-2020.This enhanced sensitivity to VPD,whose interannual variability has also increased synchronously,may have contributed to the rise in P.purpurea growth variability.Additionally,the maximum temperature in May was positively correlated with P.purpurea growth;however,there is little evidence that this factor contributed to the observed increase in growth variability.These findings provide new insights into P.purpurea growth trends and improve our understanding of the potential future impacts of climate change on forest ecosystems.展开更多
Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of P...Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of Picea crass ifolia(Qinghai spruce)during the growing seasons of2021-2023 under intensifying drought at three altitudes in Qilian Mountains,Northwest China.Our results revealed synchronous seasonal patterns in soluble sugar,starch,and total non-structural carbohydrate within the same year,contrasting with marked altitudinal disparities.As drought progressed(from 2021 to 2023),soluble sugars initially increased(2022)then declined(2023),while starch showed consistent reduction(except leaves).Moreover,the altitude of peak NSCs concentrations shifted from 3200 m in 2021to 2700 m in 2023.In particular,prolonged drought alters the environmental factors affecting NSCs.NSCs demonstrated significant positive correlations with soil temperature during humid 2021,then negatively with air temperature,vapor pressure deficit,and precipitation during 2022's initial drought,whereas under 2023's persistent drought conditions,soil temperature and water content emerged as dominant drivers.Concurrently,the ratio of soluble sugar to starch transitioned from air temperature and precipitation associations(2021-2022)to soil parameter dependence in2023.These findings provide new insights into the seasonal carbon dynamics of Qinghai spruce and the environmental response mechanisms under increasing drought stress,contributing to a better understanding of tree physiological adaptations in drought stress.展开更多
基金the funding from the Mixed Fund of the National Council of Humanities,Sciences,and Technologies of Mexico and the National Forestry Commission (CON-ACYT-CONAFOR-2017-4-292615)SECIHTI provided a graduate scholarship to Carlos Alberto Segura Sánchez (776540).
文摘Forest ecosystems worldwide can be affected by extreme climatic events.Trees respond to these occurrences in multidimensional ways,involving various mechanisms,to deal with the effects and restore the forests to their optimal state.Such abilities are known as resilience.Tree ring analysis can be used to evaluate drought resilience.Analysis of dendrophenotypes,together with genetic studies,has become an essential tool for identifying drought resilient genotypes.This study aimed to determine the dendrogenomic resilience mechanisms in the fragmented,isolated,rare endemic Mexican species Picea martinezii and P.mexicana by analysis of annual rings and the associations with SNP markers identified by genotyping by sequencing(GBS).Increment cores and needles for GBS for resilience analysis were collected from P.martinezii trees in three populations,and from P.mexicana trees in two populations.The results show that fundamental dendrogenomic mechanisms were associated with drought resilience in P.martinezii and P.mexicana.PC1 in PCA for five outlier SNPs was linked to annual tracheid width variations in P.martinezii caused by severe drought events in 1962,1989,1998 and 2011.These five outlier SNPs were located in genes coding the proteins reticulon-like protein B22,pollen-specific leucine-rich repeat extension,ornithine decarboxylase like,LisH/CRA/RING-U-box domains-containing protein and proline transporter 2-like isoform X1,which are important in the dry stress tolerance metabolism involved in the resilience response in plants.The discovery of genetic markers associated with drought resilience highlights the importance of preserving genetic diversity.
基金funded by the Science and Technology Program of Gansu Province(25JRRA487)the National Natural Science Foundation of China(42101072)the Key Research and Development Program of Gansu Province(22YF7FA029).
文摘Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to ongoing debate in this field.Moreover,gaps remain in understanding the climatic mechanisms driving increased tree growth variability,particularly for species simultaneously limited by multiple climate factors.In this study,we assessed the temporal trends in variability of Picea purpurea radial growth and its linkage with growth-climate sensitivity utilizing dendrochronological methods.Our results revealed a significant increase in P.purpurea radial growth variability from 1960 to 2020,as indicated by continuous rises in the standard deviation,coefficient of variation,and mean sensitivity of tree-ring width indices.The increased frequency of extreme growth declines further supported this finding.Furthermore,moisture condition in July was identified as a key limiting factor of P.purpurea growth.Notably,the strengthening relationship between tree-ring width indices and vapor pressure deficit(VPD)suggests that the moisture sensitivity for P.purpurea growth has increased over the period 1960-2020.This enhanced sensitivity to VPD,whose interannual variability has also increased synchronously,may have contributed to the rise in P.purpurea growth variability.Additionally,the maximum temperature in May was positively correlated with P.purpurea growth;however,there is little evidence that this factor contributed to the observed increase in growth variability.These findings provide new insights into P.purpurea growth trends and improve our understanding of the potential future impacts of climate change on forest ecosystems.
基金supported by the National Natural Science Foundation of China(No.42277481,42007410,32271667,42207537)。
文摘Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of Picea crass ifolia(Qinghai spruce)during the growing seasons of2021-2023 under intensifying drought at three altitudes in Qilian Mountains,Northwest China.Our results revealed synchronous seasonal patterns in soluble sugar,starch,and total non-structural carbohydrate within the same year,contrasting with marked altitudinal disparities.As drought progressed(from 2021 to 2023),soluble sugars initially increased(2022)then declined(2023),while starch showed consistent reduction(except leaves).Moreover,the altitude of peak NSCs concentrations shifted from 3200 m in 2021to 2700 m in 2023.In particular,prolonged drought alters the environmental factors affecting NSCs.NSCs demonstrated significant positive correlations with soil temperature during humid 2021,then negatively with air temperature,vapor pressure deficit,and precipitation during 2022's initial drought,whereas under 2023's persistent drought conditions,soil temperature and water content emerged as dominant drivers.Concurrently,the ratio of soluble sugar to starch transitioned from air temperature and precipitation associations(2021-2022)to soil parameter dependence in2023.These findings provide new insights into the seasonal carbon dynamics of Qinghai spruce and the environmental response mechanisms under increasing drought stress,contributing to a better understanding of tree physiological adaptations in drought stress.
