The effects of long-day photoperiod on growth,photo synthetic fluorescence,carbon and nitrogen metabolism,and yield of Dendrocalamopsis oldhami and the compensation effects of fertilization were investigated.A complet...The effects of long-day photoperiod on growth,photo synthetic fluorescence,carbon and nitrogen metabolism,and yield of Dendrocalamopsis oldhami and the compensation effects of fertilization were investigated.A completely randomized design was used with two light factors(bamboo culms cultivated in solar greenhouse under long-day[Ls]and short-day[Ln]treatments);two organic nitrogen fertilizer levels(application of organic fertilizer[OF]and no organic fertilizer[NF]);and three nitrogen fertilizer levels(Low[N0],medium[N1]and high nitrogen[N2]).Leaf chlorophyll and fluorescence parameters(φPo,PIABS,and ETo/CSm)decreased and DIo/CSmincreased in Ls compared to Ln.Indole acetic acid(IAA)and gibberellic acid(GA3)levels decreased,whereas abscisic acid(ABA)increased.Leaf area decreased and leaf dry mass increased.The contents of carbon and nitrogen metabolism-related enzymes(nitrate reductase,glutamine synthetase,amylase,and sucrose synthase)and products(total nitrogen,organic carbon,soluble sugar,and starch)increased.Single bamboo shoot weight and diameter at breast height decreased,whereas shoot quantity and total yield increased.Fertilizer application significantly affected physiological growth and yield in the two light treatments,thus promoting carbon and nitrogen metabolism.TheφPo,PIABS,IAA,and GA3contents increased slightly,whereas ABA levels decreased.Shoot quantity,individual weight,and total yield improved.IA A,soluble sugar,and total yield to organic manure and light were lower than those of nitrogen levels(FN>FL,FO).Other indicators showed lower responses to different fertilization treatments than the light factor(FL>FN,FO).The ability of D.oldhami to alter its morphological and physiobiochemical traits and yield in response to variations in light applications may translate into high phenotypic plasticity.Fertilization significantly improved photoplasticity of D.oldhami.Under Ls,D.oldhami had high metabolic rates.was easily inhibited by light,and showed accelerated leaf senescence,and shoot quantity and total output increased.However,the quality of individual shoots decreased.Different fertilization treatments affected D.oldhami differently under the two light intensities.Ls sensitivity to nitrogen was higher.Fertilization could delay leaf dormancy and senescence under Ls treatment.Organic fertilizer addition could improve yield more effectively,with OFN1being the optimal fertilization level.展开更多
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in l...Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.展开更多
The fluctuations of storage temperature and humidity detrimentally affect the bamboo quality and longevity,making it crucial to investigate.Herein,we explored the physical and mechan-ical properties of moso bamboo(Phy...The fluctuations of storage temperature and humidity detrimentally affect the bamboo quality and longevity,making it crucial to investigate.Herein,we explored the physical and mechan-ical properties of moso bamboo(Phyllostachys edulis)subjected to 100-day moist heat cycling aging(MHCA-1:transitioning from low-temperature/high-humidity to high-temperature/low-humidity;MHCA-2:transitioning from low-temperature/low-humidity to high-temperature/high-humidity;CHT:25℃-constant temperature and 60%relative humidity)alongside a control group.Employing a multiscale characterization and Random Forest(RF)modeling,we evaluated the im-pacts of temperature and humidity fluctuations on the bamboo quality,and the influence mech-anism of storage conditions on its physical and mechanical properties were elucidated.Results indicated that elevated temperature and humidity led to remarkable fluctuation in bamboo mois-ture(from−20.36%to 32.99%),weight gain(from−32.69%to 6.19%),and dimensional expan-sion(from−5.37%to 2.38%).Conversely,high-temperature and low-humidity drying conditions resulted in moisture loss and dimensional shrinkage.Total color difference(TCD)of bamboo cor-tex followed the order:MHCA-2(7.46)<CHT(12.24)<MHCA-1(20.10)<control(22.63).The TCD of bamboo pith positively was related with storage temperature.Periodic moist heat aging induced the permanent deformation in bamboo,reducing its elastic modulus by 30.05%-43.79%.Under moist heat aging conditions,the characteristic hemicellulose functional groups,including hydroxyl(−OH),carbonyl(C=O),ether(C-O-C),and aromatic C=C moieties exhibited re-markable structural modifications,i.e.,peak weakening,shifting,or morphological alterations in Fourier transform infrared(FT-IR)spectra.Additionally,these conditions elevated the thermal decomposition onset temperature of cellulose while decreasing its peak intensity.Overall,the RF modeling approach demonstrated a high accuracy in predicting bamboo behavior under varying moisture-heat conditions.It improved bamboo storage and recycling by supporting sorting and grading with reliable long-term data.展开更多
基金Basic Scientific Research Funding of the International Center for Bamboo and Rattan(1632020023)。
文摘The effects of long-day photoperiod on growth,photo synthetic fluorescence,carbon and nitrogen metabolism,and yield of Dendrocalamopsis oldhami and the compensation effects of fertilization were investigated.A completely randomized design was used with two light factors(bamboo culms cultivated in solar greenhouse under long-day[Ls]and short-day[Ln]treatments);two organic nitrogen fertilizer levels(application of organic fertilizer[OF]and no organic fertilizer[NF]);and three nitrogen fertilizer levels(Low[N0],medium[N1]and high nitrogen[N2]).Leaf chlorophyll and fluorescence parameters(φPo,PIABS,and ETo/CSm)decreased and DIo/CSmincreased in Ls compared to Ln.Indole acetic acid(IAA)and gibberellic acid(GA3)levels decreased,whereas abscisic acid(ABA)increased.Leaf area decreased and leaf dry mass increased.The contents of carbon and nitrogen metabolism-related enzymes(nitrate reductase,glutamine synthetase,amylase,and sucrose synthase)and products(total nitrogen,organic carbon,soluble sugar,and starch)increased.Single bamboo shoot weight and diameter at breast height decreased,whereas shoot quantity and total yield increased.Fertilizer application significantly affected physiological growth and yield in the two light treatments,thus promoting carbon and nitrogen metabolism.TheφPo,PIABS,IAA,and GA3contents increased slightly,whereas ABA levels decreased.Shoot quantity,individual weight,and total yield improved.IA A,soluble sugar,and total yield to organic manure and light were lower than those of nitrogen levels(FN>FL,FO).Other indicators showed lower responses to different fertilization treatments than the light factor(FL>FN,FO).The ability of D.oldhami to alter its morphological and physiobiochemical traits and yield in response to variations in light applications may translate into high phenotypic plasticity.Fertilization significantly improved photoplasticity of D.oldhami.Under Ls,D.oldhami had high metabolic rates.was easily inhibited by light,and showed accelerated leaf senescence,and shoot quantity and total output increased.However,the quality of individual shoots decreased.Different fertilization treatments affected D.oldhami differently under the two light intensities.Ls sensitivity to nitrogen was higher.Fertilization could delay leaf dormancy and senescence under Ls treatment.Organic fertilizer addition could improve yield more effectively,with OFN1being the optimal fertilization level.
基金supported by the Key Project of National Key Research and Development Plans(2016YFC0500204)the Chinese National Basic Research Program(2013BAC03B05)+1 种基金the Key Project for the Strategic Science Plan in Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(No.2012ZD007)State Forestry Administration project948(2014-4-58)
文摘Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.
基金support from the National Key R&D Program in the 14th Five-Year Plan of China(No.2023YFD2201202).
文摘The fluctuations of storage temperature and humidity detrimentally affect the bamboo quality and longevity,making it crucial to investigate.Herein,we explored the physical and mechan-ical properties of moso bamboo(Phyllostachys edulis)subjected to 100-day moist heat cycling aging(MHCA-1:transitioning from low-temperature/high-humidity to high-temperature/low-humidity;MHCA-2:transitioning from low-temperature/low-humidity to high-temperature/high-humidity;CHT:25℃-constant temperature and 60%relative humidity)alongside a control group.Employing a multiscale characterization and Random Forest(RF)modeling,we evaluated the im-pacts of temperature and humidity fluctuations on the bamboo quality,and the influence mech-anism of storage conditions on its physical and mechanical properties were elucidated.Results indicated that elevated temperature and humidity led to remarkable fluctuation in bamboo mois-ture(from−20.36%to 32.99%),weight gain(from−32.69%to 6.19%),and dimensional expan-sion(from−5.37%to 2.38%).Conversely,high-temperature and low-humidity drying conditions resulted in moisture loss and dimensional shrinkage.Total color difference(TCD)of bamboo cor-tex followed the order:MHCA-2(7.46)<CHT(12.24)<MHCA-1(20.10)<control(22.63).The TCD of bamboo pith positively was related with storage temperature.Periodic moist heat aging induced the permanent deformation in bamboo,reducing its elastic modulus by 30.05%-43.79%.Under moist heat aging conditions,the characteristic hemicellulose functional groups,including hydroxyl(−OH),carbonyl(C=O),ether(C-O-C),and aromatic C=C moieties exhibited re-markable structural modifications,i.e.,peak weakening,shifting,or morphological alterations in Fourier transform infrared(FT-IR)spectra.Additionally,these conditions elevated the thermal decomposition onset temperature of cellulose while decreasing its peak intensity.Overall,the RF modeling approach demonstrated a high accuracy in predicting bamboo behavior under varying moisture-heat conditions.It improved bamboo storage and recycling by supporting sorting and grading with reliable long-term data.
