A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis Carr.along an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central C...A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis Carr.along an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central China to analyze the effect of varying temperature and precipitation on growth along the gradi-ent.Correlation analyses showed that at all three altitudes and the TRW and EWW chronologies generally had signifi-cant negative correlations with mean and maximum tem-peratures in the current April and May and with minimum temperatures in the prior July and August,but significant positive correlations with precipitation in the current May.Correlations were generally significantly negative between LWW chronologies and all temperatures in the prior July and August,indicating that the prior summer temperature had a strong lag effect on the growth of P.tabuliformis that increased with altitude.The correlation with the standard-ized precipitation evapotranspiration index(SPEI)confirmed that wet conditions in the current May promoted growth of TR and EW at all altitudes.Significant altitudinal differences were also found;at 1400 m,there were significant positive correlations between EWW chronologies and SPEI in the current April and significant negative correlations between LWW chronologies and SPEI in the current September,but these correlations were not significant at 1450 m.At 1350 m,there were also significant negative correlations between the TRW and the EWW chronologies and SPEI in the prior October and the current July and between LWW chronology and SPEI in the current August,but these cor-relations were not significant at 1400 m.Moving correlation results showed a stable response of EWW in relation to the SPEI in the current May at all three altitudes and of LWW to maximum temperature in the prior July-August at 1400 m from 2002 to 2018.The EWW chronology at 1400 m and the LWW chronology at 1450 m were identified as more suitable for climate reconstruction.These results provide a strong scientific basis for forest management decisions and climate reconstructions in Central China.展开更多
We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in al...We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in all traits related to seed production. Repeatability of these traits ranged from 0 to 0.96. Seed production per ramet （SPPR）, seed producing index （SPI）, the number of relative female strobili （RFS）, the number of scales, and the num- ber of ineffective scales had comparatively high repeata- bility at 0.86, 0.87, 0.89, 0.96, and 0.91, respectively. Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone. Finally, we showed that SPI was the best predictor of the seed-producing ability of clones. Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards.展开更多
Three kinds of plant growth regulators, gibberellinA 4/7 （GA 4/7 ）, 6-benzylaminopurine （BA）, and chlormequat chloride （CCC）, were evaluated for their ability to promote strobilus and cone production in a Chines...Three kinds of plant growth regulators, gibberellinA 4/7 （GA 4/7 ）, 6-benzylaminopurine （BA）, and chlormequat chloride （CCC）, were evaluated for their ability to promote strobilus and cone production in a Chinese pine （Pinus tabuliformis Carr.） clonal seed orchard. Treatments （0, 250, 500, or 1000 mg L -1 ） were applied during three periods （June- July, July-August and August-September） in 2005. Of the three plant growth regulators, GA 4/7 was the best for promoting flower and cone production. Trees sprayed with GA 4/7 （500 mg L -1 ） from June to September had significantly more female strobili and immature cones than controls and other treatments （p≤0.0001）. The best time to apply GA 4/7 was in June. BA at 500 mg L -1 significantly increased female flower and immature cone production, compared to other treatments and controls （p≤0.0001）, while promotion of male strobili was unchanged. Chlormequat chloride at 1000 mg L -1 significantly increased the number of male strobili, compared to the other treatments （p≤0.0001）. Spraying CCC at500 mg L -1 significantly increased the number of female strobili, compared to controls （p0.05）, but it had no effect on immature cone production （p0.05）. These results are important for improving seed production and seed orchard management of Chinese pine.展开更多
Variations in the phenotypic characteristics of conifer needles is a consequence of genetic evolution that has been widely used in geographic variation and ecological studies.Although many studies are based on an in s...Variations in the phenotypic characteristics of conifer needles is a consequence of genetic evolution that has been widely used in geographic variation and ecological studies.Although many studies are based on an in situ sampling strategy and generally realize the contribution of environmental effects to variation in needle traits,it is still uncertain which needle traits are most influenced by genetic effects and which are most influenced by the environment.Using both a common garden experiment to eliminate environmental heterogeneity and an in situ sampling strategy,we compared 18 Pinus tabuliformis needle traits among 10 geographical populations.Using both sampling strategies,we found significant differences in needle traits among populations and among individuals within populations.Differences in the‘‘among-population’’variance component between the two sampling strategies revealed the environmental contribution among natural populations for each trait.The among-population variance in the following traits exceeded 8%:needle length,number of stomata within 2 mm(NS2),number of stomatal lines on the planar side,number of resin canals(RCN)and the resin canal area(RCA).For the stability of needle traits,NS2,RCN,RCA,ratio of the vascular bundle area to the RCA(VBA/RCA),and MA/RCA differed significantly in more than five provenance changes between the common garden populations and natural populations,which may be susceptible to environmental effects.Conversely,the crosssectional area,mesophyll area(MA),MA/(VBA+RCA),and MA/VBA were phenotypically stable.Geographic variation patterns and systematic relation of needle traits differed between the two sampling strategies,suggesting that in situ sampling results may reflect environmental effects and deviate statistical parameters for genetic study.Future studies of genetic evolution in the context of geographic variation should be based on appropriate sampling strategies and stable phenotypic traits.展开更多
To improve wood quality for pulpwood industries, it is important to examine not only wood density but also its components, especially tracheid characteristics. We studied genetic variations in the following tracheid t...To improve wood quality for pulpwood industries, it is important to examine not only wood density but also its components, especially tracheid characteristics. We studied genetic variations in the following tracheid traits by earlywood （EW） and latewood （LW）： tracheid length （TL）, double wall thickness （WT）, radial lumen diameter （R_D1）, tangential lumen diameter （T_D1）, radial central diameter （R_D2）, and tangential central diameter （T_D2）. We also studied the relationship with the following growth traits： diameter at breast height （DBH）, height （H）, crown breadth south-north axis （NSC）, crown breadth east-west axis （EWC）, ring width （RW）, latewood percentage （LWP）, and wood density （WD）. All sample materials were collected from a 33-year old clonal seed orchard of Pinus tabuliformis Carr. Genetic variation among clones was moderate for all tracheid traits, 9.49-26.03%. Clones significantly affected WT, R_D1, R_D2, T_D1, T_D2, and the two ratios WT/R_D1 and TL/T_D2 in EW but had no effects in LW. Clones significantly affected TL in LW but had no effects in EW. H2/C was higher in LW （0.50） than in EW （0.20） for TL, while H 2/C was higher in EW （0.27-0.46） for other tracheid traits and the two ratios （TL/T_D2 and WT/R_D1） than in EW （0.06-0.22）. WD and TL were significantly positively correlated, but WT and TL were negatively correlated both at individual and clone levels; all tracheid diameters and the four ratio values （EW_WT/ R_D1, LW WT/R_D1, EW_TL/T_D2 and LW_TL/ T_D2）, were strongly positively correlated with DBH, H, NSC, WEC and RW, and strongly negatively correlated with WD both at individual and clone levels. The most important variables for predicting WD were LW_TL, EW_WT and R_D1 in both EW and LW （r2= 0.22）. Selecting the top 10% of the clones by DBH would improve DBH growth by 12.19% （wood density was reduced by 0.14%） and produced similar responses between EW and LW for all tracheid traits： a reduction of 0.94 and 3.69% in tracheid length and increases in tracheid diameters （from 0.36 to 5.24%） and double wall thickness （0.07 and 0.87%）. The two ratios WT/R_D1 and TL/T_D2 across tissues （EW and LW） declined 0.59 and 4.56%, respectively. The decreased tracheid length and the ratio between tracheid length and diameter is disadvantageous for pulp production. The unfavorable relationship of tracheid traits with wood density indicate that multiple trait selection using optimal economic weights and optimal breeding strategies are recommended for the current longterm breeding program for P. tabuliformis.展开更多
We employed capacitance to evaluate the kinship and interspecific variation of homoploid hybrid conifer Pinus densata,P.tabuliformis,P.yunnanensis and artificial hybrids of P.tabuliformis(maternal parent)and P.yunnane...We employed capacitance to evaluate the kinship and interspecific variation of homoploid hybrid conifer Pinus densata,P.tabuliformis,P.yunnanensis and artificial hybrids of P.tabuliformis(maternal parent)and P.yunnanensis(paternal parent)which were cultivated and selected in the common garden experiment.By measuring capacitance spectra under different voltage frequencies,we could differentiate different germplasms based on the electrical response.We aims to demonstrate that P.densata as the hybrid of P.tabuliformis and P.yunnanensis based on the capacitance values of the species,and to provide new evidence to the previously known biological evidence,as well as and the parental effect on the hybrids.Our results revealed that capacitance values between the species are significantly different in the spectra where P.yunnanensis positioned at the lowest and P.densata was much higher than all other species,indicating that P.densata had possessed a great capacity to store electrical energy.The capacitance spectra of P.densata and the artificial hybrid are not similar,which rejected our hypothesis.Both of the capacitance values of P.densata and the hybrids were closer to P.tabuliformis than to P.yunnanensis,which shows that the maternal influence was stronger than the paternal influence.Correlation analysis on the relationship between capacitance and fitnessrelated characteristics showed that capacitance is negatively correlated to mortality rate,and positively correlated with second-year survival rate.High capacitance values of P.densata and some of the hybrids reveal their superior adaptability to harsh environment in the Tibet Plateau.We concluded that capacitance as a new indicator for plant fitness and evolution evidence of homoploid hybrid conifers.展开更多
Biological volatile organic compounds(BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rate...Biological volatile organic compounds(BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rates of BVOCs from Pinus tabuliformis, using an enclosure technique. Environmental parameters(temperature and light intensity) and physiological parameters(net photosynthetic rate, P_n; stomatal conductance, g_s; intercellular CO_2 concentration, C_i; and transpiration rate, T_r) that may affect emission behavior were continuously monitored. The 10 most abundant compound groups emitted by P. tabuliformis were classified by gas chromatography–mass spectrometry. The dominant monoterpenoid compounds emitted were α-pinene, β-myrcene, α-farnesene and limonene. The diurnal emission rate of BVOCs changed with temperature and light intensity, with dynamic analysis of BVOCs emissions revealing that their emission rates were more affected by temperature than light. The variation in monoterpene emission rates was consistent with estimates of P_n, g_s and T_r. Basal emission rates(at 30 °C,) of the main BVOCs ranged from 0.006 to 0.273 μg^(-1)/(hr g),while the basal ER standardization coefficients ranged from 0.049 to 0.144 °C^(-1). Overall, these results provide a detailed reference for the effective selection and configuration of tree species to effectively prevent and control atmospheric pollution.展开更多
It is essential to understand the water consumption characteristics and physiological adjustments of tree species under drought conditions,as well as the effects of pure and mixed plantations on these characteristics ...It is essential to understand the water consumption characteristics and physiological adjustments of tree species under drought conditions,as well as the effects of pure and mixed plantations on these characteristics in semi-arid regions.In this study,the normalized sap flow(SFn),leaf water potential,stomatal conductance(gs),and photosynthetic rate(Pr)were monitored for two dominant species,i.e.,Pinus tabuliformis and Hippophae rhamnoides,in both pure and mixed plantations in a semi-arid region of Chinese Loess Plateau.A threshold-delay model showed that the lower rainfall thresholds(RL)for P.tabuliformis and H.rhamnoides in pure plantations were 9.6 and 11.0 mm,respectively,and the time lags(τ)after rainfall were 1.15 and 1.76 d for corresponding species,respectively.The results indicated that P.tabuliformis was more sensitive to rainfall pulse than H.rhamnoides.In addition,strong stomatal control allowed P.tabuliformis to experience low gsand Prin response to drought,while maintaining a high midday leaf water potential(Ψm).However,H.rhamnoides maintained high gsand Prat a lowΨmexpense.Therefore,P.tabuliformis and H.rhamnoides can be considered as isohydric and anisohydric species,respectively.In mixed plantation,the values of RLfor P.tabuliformis and H.rhamnoides were 6.5 and 8.9 mm,respectively;and the values ofτwere 0.86 and 1.61 d for corresponding species,respectively,which implied that mixed afforestation enhanced the rainfall pulse sensitivity for both two species,especially for P.tabuliformis.In addition,mixed afforestation significantly reduced SFn,gs,and Prfor P.tabuliformis(P<0.05),while maintaining a high leaf water potential status.However,no significant effect of mixed afforestation of H.rhamnoides was observed at the expense of leaf water potential status in response to drought.Although inconsistent physiological responses were adopted by these species,the altered water consumption characteristics,especially for P.tabuliformis indicated that the mixed afforestation requires further investigation.展开更多
In angiosperms, low red (R)/far-red (FR) ratio light increases gibberellin (GA) levels. GA signaling in conifer seedlings requires FR to promote shoot elongation and reduce the inhibition of shoot elongation induced b...In angiosperms, low red (R)/far-red (FR) ratio light increases gibberellin (GA) levels. GA signaling in conifer seedlings requires FR to promote shoot elongation and reduce the inhibition of shoot elongation induced by paclobutrazol (PAC), yet the effects of far-red light in inducing shoot elongation in the presence or absence of PAC is poorly understood. In this study, transcriptomic and proteomic analyses was used to examine the molecular mechanism of FR regulation of shoot elongation in Chinese pine (Pinus tabuliformis Carr.) seedlings in the presence of PAC. Four treatments were compared: white light + water (WW), FR + water (RW), white light + PAC (WP), and FR + PAC (RP), and 1436 differentially expressed genes (DEGs) and 450 differentially expressed proteins (DEPs) were identified in RW_WW (RW contrast WW), and 1862 DEGs and 481 DEPs in RP_WP (RP contrast WP). Metabolic and signal transduction pathway analyses of DEGs and DEPs in RW_WW and RP_WP, indicated that the former required more energy than the latter. Moreover, gibberellic acid, auxin, and brassinolide are equally important in RW_WW and RP_WP for shoot elongation, except for the ethylene pathway. Amino acid metabolism and cell wall organization were significantly enriched in RW_WW and RP_WP, respectively. In summary, RW_WW and RP_WP had different effects in secondary metabolism, energy metabolism, amino acid metabolism, cell wall organization, and hormone response. These results provide an important theoretical and reference basis for studying the regulatory effect of low R/FR and PAC in conifer shoot elongation.展开更多
The dynamic variation of net primary productivity of artificial Pinus tabulaeformis forest was studied in Shanxi Province,and potential productivity of artificial forest was predicted to provide reference for improvin...The dynamic variation of net primary productivity of artificial Pinus tabulaeformis forest was studied in Shanxi Province,and potential productivity of artificial forest was predicted to provide reference for improving quality of regional forest stand. The regression equation was established by using the stratification and harvesting method with the relative growth model. Cumulative method and Thornthwaite Memorial model was used to estimate the actual and potential productivity of the forest. The productivity of P. tabulaeformis forest increased with the increase of age and started decrease with the mature period. The actual productivity of P. tabulaeformis forest was 4. 462 t/( ha·year); the contribution rate of trees was 72. 17% of the total productivity,and with the increase of age,the total biomass increased but productivity decreased at late near-mature forest; the contribution rate of herb layer was 21. 16% in the young forest stage,and then decreased gradually. On the contrary,the contribution rate of shrub layer increased gradually,and the contribution rate of the grassland was more than that of the herb layer,so as the key period of structural management; the average potential productivity of forest was 8. 422 t/( ha·year),and the potential space of P. tabulaeformis was at least 32% in Shanxi Province. In conclusion,the potential space of productivity of P. tabulaeformis was at least 32%,and the primary limiting factor of P. tabulaeformis forest productivity in Shanxi Province was rainfall.展开更多
基金This research was funded by National Key Research and Development Program of China(No.2018YFA0605601)National Natural Science Foundation of China(No.42077417,41671042).
文摘A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis Carr.along an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central China to analyze the effect of varying temperature and precipitation on growth along the gradi-ent.Correlation analyses showed that at all three altitudes and the TRW and EWW chronologies generally had signifi-cant negative correlations with mean and maximum tem-peratures in the current April and May and with minimum temperatures in the prior July and August,but significant positive correlations with precipitation in the current May.Correlations were generally significantly negative between LWW chronologies and all temperatures in the prior July and August,indicating that the prior summer temperature had a strong lag effect on the growth of P.tabuliformis that increased with altitude.The correlation with the standard-ized precipitation evapotranspiration index(SPEI)confirmed that wet conditions in the current May promoted growth of TR and EW at all altitudes.Significant altitudinal differences were also found;at 1400 m,there were significant positive correlations between EWW chronologies and SPEI in the current April and significant negative correlations between LWW chronologies and SPEI in the current September,but these correlations were not significant at 1450 m.At 1350 m,there were also significant negative correlations between the TRW and the EWW chronologies and SPEI in the prior October and the current July and between LWW chronology and SPEI in the current August,but these cor-relations were not significant at 1400 m.Moving correlation results showed a stable response of EWW in relation to the SPEI in the current May at all three altitudes and of LWW to maximum temperature in the prior July-August at 1400 m from 2002 to 2018.The EWW chronology at 1400 m and the LWW chronology at 1450 m were identified as more suitable for climate reconstruction.These results provide a strong scientific basis for forest management decisions and climate reconstructions in Central China.
基金supported by ‘‘the Fundamental Research Funds for the Central Universities(No.2015ZCQ-SW-02)’’ and ‘‘Special Fund for Forestry Scientific Research in the Public Interest(No.201104022)’’
文摘We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in all traits related to seed production. Repeatability of these traits ranged from 0 to 0.96. Seed production per ramet （SPPR）, seed producing index （SPI）, the number of relative female strobili （RFS）, the number of scales, and the num- ber of ineffective scales had comparatively high repeata- bility at 0.86, 0.87, 0.89, 0.96, and 0.91, respectively. Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone. Finally, we showed that SPI was the best predictor of the seed-producing ability of clones. Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards.
基金Partial funding for this research was provided by The State Forestry Administration of China(No.2006-85)
文摘Three kinds of plant growth regulators, gibberellinA 4/7 （GA 4/7 ）, 6-benzylaminopurine （BA）, and chlormequat chloride （CCC）, were evaluated for their ability to promote strobilus and cone production in a Chinese pine （Pinus tabuliformis Carr.） clonal seed orchard. Treatments （0, 250, 500, or 1000 mg L -1 ） were applied during three periods （June- July, July-August and August-September） in 2005. Of the three plant growth regulators, GA 4/7 was the best for promoting flower and cone production. Trees sprayed with GA 4/7 （500 mg L -1 ） from June to September had significantly more female strobili and immature cones than controls and other treatments （p≤0.0001）. The best time to apply GA 4/7 was in June. BA at 500 mg L -1 significantly increased female flower and immature cone production, compared to other treatments and controls （p≤0.0001）, while promotion of male strobili was unchanged. Chlormequat chloride at 1000 mg L -1 significantly increased the number of male strobili, compared to the other treatments （p≤0.0001）. Spraying CCC at500 mg L -1 significantly increased the number of female strobili, compared to controls （p0.05）, but it had no effect on immature cone production （p0.05）. These results are important for improving seed production and seed orchard management of Chinese pine.
基金funded by the Fundamental Research Funds for the Central Universities(2015ZCQ-SW-02)
文摘Variations in the phenotypic characteristics of conifer needles is a consequence of genetic evolution that has been widely used in geographic variation and ecological studies.Although many studies are based on an in situ sampling strategy and generally realize the contribution of environmental effects to variation in needle traits,it is still uncertain which needle traits are most influenced by genetic effects and which are most influenced by the environment.Using both a common garden experiment to eliminate environmental heterogeneity and an in situ sampling strategy,we compared 18 Pinus tabuliformis needle traits among 10 geographical populations.Using both sampling strategies,we found significant differences in needle traits among populations and among individuals within populations.Differences in the‘‘among-population’’variance component between the two sampling strategies revealed the environmental contribution among natural populations for each trait.The among-population variance in the following traits exceeded 8%:needle length,number of stomata within 2 mm(NS2),number of stomatal lines on the planar side,number of resin canals(RCN)and the resin canal area(RCA).For the stability of needle traits,NS2,RCN,RCA,ratio of the vascular bundle area to the RCA(VBA/RCA),and MA/RCA differed significantly in more than five provenance changes between the common garden populations and natural populations,which may be susceptible to environmental effects.Conversely,the crosssectional area,mesophyll area(MA),MA/(VBA+RCA),and MA/VBA were phenotypically stable.Geographic variation patterns and systematic relation of needle traits differed between the two sampling strategies,suggesting that in situ sampling results may reflect environmental effects and deviate statistical parameters for genetic study.Future studies of genetic evolution in the context of geographic variation should be based on appropriate sampling strategies and stable phenotypic traits.
基金supported by “Open Fund of State Key Laboratory of Tree Genetics and Breeding(Chinese Academy of Forestry)(Grant No.TGB2016001)”“The Lecture and Study Program for Outstanding Scholars from Home and Abroad(Grant No.CAFYBB2011007)”“Continuation project of National Natural Science Foundation of China(Grant No.CAFNSFC201601)”
文摘To improve wood quality for pulpwood industries, it is important to examine not only wood density but also its components, especially tracheid characteristics. We studied genetic variations in the following tracheid traits by earlywood （EW） and latewood （LW）： tracheid length （TL）, double wall thickness （WT）, radial lumen diameter （R_D1）, tangential lumen diameter （T_D1）, radial central diameter （R_D2）, and tangential central diameter （T_D2）. We also studied the relationship with the following growth traits： diameter at breast height （DBH）, height （H）, crown breadth south-north axis （NSC）, crown breadth east-west axis （EWC）, ring width （RW）, latewood percentage （LWP）, and wood density （WD）. All sample materials were collected from a 33-year old clonal seed orchard of Pinus tabuliformis Carr. Genetic variation among clones was moderate for all tracheid traits, 9.49-26.03%. Clones significantly affected WT, R_D1, R_D2, T_D1, T_D2, and the two ratios WT/R_D1 and TL/T_D2 in EW but had no effects in LW. Clones significantly affected TL in LW but had no effects in EW. H2/C was higher in LW （0.50） than in EW （0.20） for TL, while H 2/C was higher in EW （0.27-0.46） for other tracheid traits and the two ratios （TL/T_D2 and WT/R_D1） than in EW （0.06-0.22）. WD and TL were significantly positively correlated, but WT and TL were negatively correlated both at individual and clone levels; all tracheid diameters and the four ratio values （EW_WT/ R_D1, LW WT/R_D1, EW_TL/T_D2 and LW_TL/ T_D2）, were strongly positively correlated with DBH, H, NSC, WEC and RW, and strongly negatively correlated with WD both at individual and clone levels. The most important variables for predicting WD were LW_TL, EW_WT and R_D1 in both EW and LW （r2= 0.22）. Selecting the top 10% of the clones by DBH would improve DBH growth by 12.19% （wood density was reduced by 0.14%） and produced similar responses between EW and LW for all tracheid traits： a reduction of 0.94 and 3.69% in tracheid length and increases in tracheid diameters （from 0.36 to 5.24%） and double wall thickness （0.07 and 0.87%）. The two ratios WT/R_D1 and TL/T_D2 across tissues （EW and LW） declined 0.59 and 4.56%, respectively. The decreased tracheid length and the ratio between tracheid length and diameter is disadvantageous for pulp production. The unfavorable relationship of tracheid traits with wood density indicate that multiple trait selection using optimal economic weights and optimal breeding strategies are recommended for the current longterm breeding program for P. tabuliformis.
文摘We employed capacitance to evaluate the kinship and interspecific variation of homoploid hybrid conifer Pinus densata,P.tabuliformis,P.yunnanensis and artificial hybrids of P.tabuliformis(maternal parent)and P.yunnanensis(paternal parent)which were cultivated and selected in the common garden experiment.By measuring capacitance spectra under different voltage frequencies,we could differentiate different germplasms based on the electrical response.We aims to demonstrate that P.densata as the hybrid of P.tabuliformis and P.yunnanensis based on the capacitance values of the species,and to provide new evidence to the previously known biological evidence,as well as and the parental effect on the hybrids.Our results revealed that capacitance values between the species are significantly different in the spectra where P.yunnanensis positioned at the lowest and P.densata was much higher than all other species,indicating that P.densata had possessed a great capacity to store electrical energy.The capacitance spectra of P.densata and the artificial hybrid are not similar,which rejected our hypothesis.Both of the capacitance values of P.densata and the hybrids were closer to P.tabuliformis than to P.yunnanensis,which shows that the maternal influence was stronger than the paternal influence.Correlation analysis on the relationship between capacitance and fitnessrelated characteristics showed that capacitance is negatively correlated to mortality rate,and positively correlated with second-year survival rate.High capacitance values of P.densata and some of the hybrids reveal their superior adaptability to harsh environment in the Tibet Plateau.We concluded that capacitance as a new indicator for plant fitness and evolution evidence of homoploid hybrid conifers.
基金supported by the Natural Science Foundation of China(Nos.31800377,31470638)the National Key Research and Development Program of China(No.2016YFC0501704)+2 种基金the National Science and Technology Program of China(No.2015BAD07B0502)the National Key Research the Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees(No.PXM2016014207000038)the Special Foundation for Beijing Common Construction Project
文摘Biological volatile organic compounds(BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rates of BVOCs from Pinus tabuliformis, using an enclosure technique. Environmental parameters(temperature and light intensity) and physiological parameters(net photosynthetic rate, P_n; stomatal conductance, g_s; intercellular CO_2 concentration, C_i; and transpiration rate, T_r) that may affect emission behavior were continuously monitored. The 10 most abundant compound groups emitted by P. tabuliformis were classified by gas chromatography–mass spectrometry. The dominant monoterpenoid compounds emitted were α-pinene, β-myrcene, α-farnesene and limonene. The diurnal emission rate of BVOCs changed with temperature and light intensity, with dynamic analysis of BVOCs emissions revealing that their emission rates were more affected by temperature than light. The variation in monoterpene emission rates was consistent with estimates of P_n, g_s and T_r. Basal emission rates(at 30 °C,) of the main BVOCs ranged from 0.006 to 0.273 μg^(-1)/(hr g),while the basal ER standardization coefficients ranged from 0.049 to 0.144 °C^(-1). Overall, these results provide a detailed reference for the effective selection and configuration of tree species to effectively prevent and control atmospheric pollution.
基金supported by the National Key R&D Program of China (2017YFA0604801)the National Natural Science Foundation of China (41501576)+1 种基金the China Special Fund for Meteorological Research in the Public Interest (Major Projects) (GYHY201506001-3)the Fundamental Research Funds for the Central Universities (2452016105)
文摘It is essential to understand the water consumption characteristics and physiological adjustments of tree species under drought conditions,as well as the effects of pure and mixed plantations on these characteristics in semi-arid regions.In this study,the normalized sap flow(SFn),leaf water potential,stomatal conductance(gs),and photosynthetic rate(Pr)were monitored for two dominant species,i.e.,Pinus tabuliformis and Hippophae rhamnoides,in both pure and mixed plantations in a semi-arid region of Chinese Loess Plateau.A threshold-delay model showed that the lower rainfall thresholds(RL)for P.tabuliformis and H.rhamnoides in pure plantations were 9.6 and 11.0 mm,respectively,and the time lags(τ)after rainfall were 1.15 and 1.76 d for corresponding species,respectively.The results indicated that P.tabuliformis was more sensitive to rainfall pulse than H.rhamnoides.In addition,strong stomatal control allowed P.tabuliformis to experience low gsand Prin response to drought,while maintaining a high midday leaf water potential(Ψm).However,H.rhamnoides maintained high gsand Prat a lowΨmexpense.Therefore,P.tabuliformis and H.rhamnoides can be considered as isohydric and anisohydric species,respectively.In mixed plantation,the values of RLfor P.tabuliformis and H.rhamnoides were 6.5 and 8.9 mm,respectively;and the values ofτwere 0.86 and 1.61 d for corresponding species,respectively,which implied that mixed afforestation enhanced the rainfall pulse sensitivity for both two species,especially for P.tabuliformis.In addition,mixed afforestation significantly reduced SFn,gs,and Prfor P.tabuliformis(P<0.05),while maintaining a high leaf water potential status.However,no significant effect of mixed afforestation of H.rhamnoides was observed at the expense of leaf water potential status in response to drought.Although inconsistent physiological responses were adopted by these species,the altered water consumption characteristics,especially for P.tabuliformis indicated that the mixed afforestation requires further investigation.
基金This work was supported by the National Natural Science Foundation of China(31770713)Biosafety and Genetic Resources Management Project of State Forestry and Grassland Administration(KJZXSA202030).
文摘In angiosperms, low red (R)/far-red (FR) ratio light increases gibberellin (GA) levels. GA signaling in conifer seedlings requires FR to promote shoot elongation and reduce the inhibition of shoot elongation induced by paclobutrazol (PAC), yet the effects of far-red light in inducing shoot elongation in the presence or absence of PAC is poorly understood. In this study, transcriptomic and proteomic analyses was used to examine the molecular mechanism of FR regulation of shoot elongation in Chinese pine (Pinus tabuliformis Carr.) seedlings in the presence of PAC. Four treatments were compared: white light + water (WW), FR + water (RW), white light + PAC (WP), and FR + PAC (RP), and 1436 differentially expressed genes (DEGs) and 450 differentially expressed proteins (DEPs) were identified in RW_WW (RW contrast WW), and 1862 DEGs and 481 DEPs in RP_WP (RP contrast WP). Metabolic and signal transduction pathway analyses of DEGs and DEPs in RW_WW and RP_WP, indicated that the former required more energy than the latter. Moreover, gibberellic acid, auxin, and brassinolide are equally important in RW_WW and RP_WP for shoot elongation, except for the ethylene pathway. Amino acid metabolism and cell wall organization were significantly enriched in RW_WW and RP_WP, respectively. In summary, RW_WW and RP_WP had different effects in secondary metabolism, energy metabolism, amino acid metabolism, cell wall organization, and hormone response. These results provide an important theoretical and reference basis for studying the regulatory effect of low R/FR and PAC in conifer shoot elongation.
基金Supported by Shanxi Province Science Foundation for Youths(201601D021115)Shanxi Province Science Foundation(201601D011063)
文摘The dynamic variation of net primary productivity of artificial Pinus tabulaeformis forest was studied in Shanxi Province,and potential productivity of artificial forest was predicted to provide reference for improving quality of regional forest stand. The regression equation was established by using the stratification and harvesting method with the relative growth model. Cumulative method and Thornthwaite Memorial model was used to estimate the actual and potential productivity of the forest. The productivity of P. tabulaeformis forest increased with the increase of age and started decrease with the mature period. The actual productivity of P. tabulaeformis forest was 4. 462 t/( ha·year); the contribution rate of trees was 72. 17% of the total productivity,and with the increase of age,the total biomass increased but productivity decreased at late near-mature forest; the contribution rate of herb layer was 21. 16% in the young forest stage,and then decreased gradually. On the contrary,the contribution rate of shrub layer increased gradually,and the contribution rate of the grassland was more than that of the herb layer,so as the key period of structural management; the average potential productivity of forest was 8. 422 t/( ha·year),and the potential space of P. tabulaeformis was at least 32% in Shanxi Province. In conclusion,the potential space of productivity of P. tabulaeformis was at least 32%,and the primary limiting factor of P. tabulaeformis forest productivity in Shanxi Province was rainfall.
