以4种棕榈植物幼苗为试材,通过盆栽控水试验,研究了干旱胁迫对其光合特性和抗氧化酶活性的影响.结果表明,随着干旱程度加剧,4种棕榈植物的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(E)均呈逐渐下降趋势,但下降幅度在不同种及不同胁迫处理之间存在差异.在轻度干旱胁迫下,气孔限制是皇后葵和砂糖椰子Pn下降的主要原因,而东澳棕和圆叶蒲葵Pn下降的主要原因是非气孔限制因素;在中度和重度干旱胁迫下,4种棕榈植物Pn下降的主要原因均为非气孔限制因素.4种棕榈植物的平均水分利用效率(WUE)依次为皇后葵＞东澳棕＞砂磄椰子＞圆叶蒲葵.轻度干旱胁迫下4种植物的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均高于对照,中度和重度胁迫下均低于对照.复水后各处理均可恢复达对照水平.4种棕榈植物以皇后葵抗干旱能力最好,其次为东澳棕和砂糖椰子,圆叶蒲葵最差,对干旱环境最为敏感.

为了研究干旱胁迫和复水对砂糖椰子(Arenga pinnata)幼苗叶片和根系的影响,以两年生砂糖椰子幼苗为材料,分别进行干旱胁迫0,7,14和21 d,再复水3和6 d,然后测定叶片和根系的超氧化物歧化酶(SOD)活性、脯氨酸(Pro)含量、可溶性蛋白含量、丙二醛(MDA)含量、相对电导率以及叶绿素含量.结果表明,叶片的SOD活性在各个处理中均呈显著的波动性变化,根系的SOD活性在干旱胁迫和复水后都显著高于对照.叶片和根系的Pro含量在重度干旱胁迫下显著升高,复水后显著降低;而可溶性蛋白含量在中度和重度干旱胁迫时均显著减少,复水3d后显著增加;叶片和根系的MDA含量变化趋势具有互补性;叶片和根系的相对电导率均随着干旱胁迫时间的延长而增加,在中度和重度干旱胁迫时显著高于其他处理,复水后减少;叶绿素含量在重度干旱胁迫时达到最高值.总之,在干旱胁迫下,叶片和根系不同指标变化规律不一样,脯氨酸含量、可溶性蛋白含量和相对电导率在叶片和根系中的变化趋势相似,SOD活性和MDA含量的变化趋势不一致,表明砂糖椰子地上部和地下部对干旱胁迫的响应具有协同效应.

The effects of 6-benzylaminopurine (6-BA) on several physiological indexes of Caryota mitis and C. obtusa seedlings treated at varied temperatures were conducted, the leaves of the two palm species were sprayed with 0, 25, 50 and 100 mg · L−1 6-BA solutions, the activities of superoxide dismutase (SOD), peroxidase (POD), and the contents of malondialdehyde (MDA), proline, soluble protein, chlorophyll and chlorophyll a/b were determined under 25°C, 5°C and 25°C for 24 h, respectively. The dynamics of a series of important physiological components derived from the leaves were studied. It was indicated that all the above mentioned physiological indexes varied with different concentrations of 6-BA and temperature. The fuzzy comprehensive evaluation values for different concentrations of 6-BA at the recovery temperature 25°C were 0.33, 0.28, 0.92 and 0.33, respectively for C. mitis, and 0.20, 0.49, 0.56 and 0.63, respectively for C. obtusa. It was concluded that leaves sprayed with different concentrations of 6-BA could affect the cold tolerance of palm seedlings. The optimal concentration of 6-BA was different for different palm species.

为了研究植物整体对干旱胁迫和复水的生理响应,以2年生的东澳棕(Carpentaria acumi-nata)实生苗为材料,分别进行干旱胁迫0、7、14d和21 d,再复水3d和6d,测定叶片和根系的超氧化物歧化酶(SOD)活性、脯氨酸(Pro)含量、可溶性蛋白含量、丙二醛(MDA)含量、相对电导率和叶绿素含量的生理指标,用于明确东澳棕叶片和根系对对干旱胁迫和复水的生理响应.结果表明:叶片的SOD活性、Pro含量、可溶性蛋白含量、MDA含量在轻度干旱胁迫7d时显著增加,随着干旱进行而减少,复水后又增加,相对电导率的变化规律与之相反.叶绿素含量在干旱胁迫21 d时达到最大值,复水后降低.根系的SOD活性只在干旱胁迫21 d时显著提高,复水后显著降低;Pro含量在干旱胁迫14 d时升高,后降低,复水后升高;可溶性蛋白含量在干旱胁迫7d时升高,后降低,复水后升高,MDA含量干旱胁迫7d时降低,干旱胁迫21 d时升高,复水后降低,根系的相对电导率在干旱胁迫7d时略增加,后降低.叶片的SOD活性和MDA含量在干旱7d-复水期间的变化趋势相同,根系的SOD活性和MDA含量在干旱7d-复水期间的变化趋势也相同,说明叶片和根系之间、SOD和MDA之间具有协同效应.干旱7d-复水期间叶片的SOD活性和MDA含量显著高于根系,干旱14d-复水期间叶片的Pro含量显著低于根系.植物地上部和根系之间存在协同和互补效应,有利于提高植物的水分的适应性.

During a survey of wild resources of Palmae in China, Caryota maxima was first found in Longhai county, Zhangzhou city of Fujian province, and the investigation of distribution, habitat and growth situation of the wild C. maxima was carried out. The results show that, firstly, Longhai county in Zhangzhou city is the northernmost and easternmost known natural distribution of C. maxima in China; Secondly, C. maxima grows well in the natural distribution, flowering or fruiting plants and plantlets are found and indicates that the offspring could regenerate in the area; Thirdly, the area distribution of C. maxima is narrow and sporadic, and the wild resources are in endangered, so they should be protected.

The effects of naphthalene acetic acid ( NAA ) on the cold tolerance of Caryota obtusa seedlings were conducted by several physiological indexes , The leaves of C.obtusa were sprayed with 0, 25, 50 and 100 mg· L-1 NAA solutions , the activities of superoxide dismutase ( SOD ) , peroxidase ( POD ) , and the contents of malondialdehyde (MDA), proline, soluble protein and chlorophyll of C.obtusa were determined under 25℃, 5℃and 25℃.It was indicated that all the above physiological indexes varied with different concentrations of NAA . Subordinate function values for different concentrations of NAA at 25℃ were 0.39 , 0.30 , 0.39 and 0.51 , respectively .It was concluded that leaves sprayed with different concentrations of NAA could affect the cold tolerance of C.obtusa seedlings and the optimal concentration was 100 mg· L-1 .

The effect of La(NO3)3 on the physiological indices of cold tolerance in Livistona chinensis seedlings was conducted,The L.chinensis seedlings were sprayed with 0,100,200,300,400,500,600 mg/L La(NO3)3 solution,the contents of malondialdehyde(MDA),soluble sugar,chlorophyll and chlorophyll a/b ratio of L.chinensis seedlings were determined under 20,5,12 and 10 ℃ for 24 h,respectively,The results of the MDA contents with La(NO3)3 treatments were lower than those of the control,and changed slowly under temperature stress,and the contents of soluble sugar,chlorophyll and chlorophyll a/b ratio increased compared with the control.It was concluded that La(NO3)3 agents could boost the physiological indices of cold tolerance in L.chinensis.And the appropriate concentration which significantly affected the physiological indices of cold tolerance was 300 mg/L.

The photosynthetic characters were observed with CI-340 portable photosynthesis determination system produced by United States.The relationships of Pn and eco-physiological factors were analyzed with path coefficient and the light-response curve was fitted with parabola model for Caryota urens and Caryota mitis.The results showed as follows:(1)The net photosynthetic rate of two species presented asymmetric double peak curve,with a clear midday depression,and its length and depth in C.urens was more obvious than that in C.mitis,and the minor peak in C.urens was also delayed about 2 hours.These differences maybe result from the various activities of physiological factors such as stomatal conductance and transpiration rate and so on.(2)Ci is the main physiological factor affecting the characteristic of Pn of two species.However,Gs was the main limiting factor in C.urens,Tleaf in C.mitis;The main ecological factor was PAR in C.urens,Cair in C.mitis and RH was the limiting factor of two species.(3)The light-response curve of two species was fitted with parabola models.The high LCP(light compensation point) and LSP(light saturation point) in two species showed that they all belonged to strongly light plant.However,these values were higher in C.urens than that in C.mitis.Thus,the latter was more adaptive to be removed from south to north.

In order to understand the effects of naphthalene acetic acid(NAA) on the cold tolerance of Caryota mitis seedlings.Solutions of NAA with the concentrations of 0,25,50 and 100 mg·L-1 were sprayed on the foliage of C.mitis seedings.Physiological indices,including activities of superoxide dismutase(SOD) and peroxidase(POD) as well as the contents of malondialdehyde(MDA),free proline(f-pro),soluble protein,chlorophylls were measured in the seedlings treated by the temperatures of-25℃,5℃,and 25℃.It was indicated that all the above-mentioned physiological indices varied with different concentrations of NAA.Subordinate function value for different concentrations of NAA at 25℃ were 0.35 for 0 mg·L-1,0.67 for 25 mg·L-1,0.53 for 50 mg·L-1,and 0.29 for 100 mg·L-1.It was concluded that leaves sprayed with different concentrations of NAA could affect the cold tolerance of C.mitis seedlings.The optimal concentration of NAA was 25 mg·L-1.

The studies on the seasonal changes of total phenolics(TP),soluble condensed tannin(SCT),bound condensed tannin(BCT) and total condensed tannin(TCT) content in the leaves of high cold resistant Butia capitata,the medium cold resistant Acoelorrhaphe wrightii and cold sensitive Elaeis guineensis were conducted in the four seasons.Differences in the accumulation of tannins associated with different cold resistant palm species occurred in response to seasons.The content of BCT in B.capitata and A.wrightii markedly decreased from autumn to winter,but not for E.guineensis.The change trend of B.capitata TCT was the same as that of TP,but not the same for that of A.wrightii and E.guineensis.The results showed that the high cold resistant B.capitata,the medium cold resistant A.wrightii and cold sensitive E.guineensis had different tannin seasonal change patterns.This character may help the further investigations into the plant cold resistant mechanism.

In this paper,in order to discuss the effects of several chemical regulation agents on the photosynthesis of Caryota urens L.and Caryota mitis Lour.under cold stress,the photosynthesis indices of seedlings treated with different concentration of chemical regulation agents responded to cold stress by CI-340.The results showed that: net photosynthetic rate(Pn)of the two species could be effectively improved under all different treatments,the effects varied in different regulation agents and in different concentration of the same agent;The 200 mg/L of paclobutrazol and 1 000 dilution ratio of mixture solution was the most effective to improve Pn of C.urens and C.mitis,respectively;The effects of different treatments on stomatal conductance(Gs),transpiration rate(E)and the concentration of intercellular CO2(Ci) were inconsistent with those on Pn.All agents examined could enhance the photosynthetic capabilities of the two species above.

The study was performed to investigate the effects of La(NO3)3 on the cold tolerance of Caryota urens seedlings.Effects of La(NO3)3 were tested by spraying the foliage of C.urens with 0,100,350 and 500 mg·L-1 La(NO3)3 solution.Then,physiological indices,including activity of superoxide dismutase(SOD) and peroxidase(POD) as well as the content of malondialdehyde(MDA),proline,soluble protein,chlorophyll,and chlorophyll a/b,were determined after treated in 25 ℃(1),5 ℃,and 25 ℃(2) for 24 h respectively in turn.It was indicated that all the above-mentioned physiological indices varied with different concentrations of La(NO3)3.Results of the fuzzy membership functions comprehensive evaluation for different La(NO3)3 solution at 25 ℃(2) were 0.39 for 0 mg·L-1,0.34 for 100 mg·L-1,0.85 for 350 mg·L-1,and 0.76 for 500 mg·L-1.It was concluded that spraying leaves with different concentrations of La(NO3)3 could affect the cold tolerance of C.urens seedlings with the most effective being 350 mg·L-1.

The effects of La(NO3)3 on cold tolerance of Caryota mitis seedlings were conducted by several physiological indices.The foliage of Caryota mitis was sprayed with 0,100,350 and 500 mg/L La(NO3)3 solution.The changes of activities of SOD,POD,and the contents of MDA,proline,soluble protein,chlorophyll and chlorophyll a/b of Caryota mitis were studied under different temperature.All the above-mentioned physiological indices varied with different solution.The results of the comprehensive evaluation indices of the fuzzy membership functions system under the 25 ℃ were 0.41,0.46,0.70 and 0.50,respectively.It was shown that spraying leaves with different concentrations of La(NO3)3 could enhance the cold tolerance of Caryota mitis seedlings,and the appropriate concentration was 350 mg/L.

Cold tolerances of Butia capitata,Acoelorrhaphe wrightii and Elaeis guineensis were studied during the winter(October of 2005 to January of 2006) in Xiamen City by cold injury index,electrolyte leakage and semi-lethal low temperature.The results show that the cold injury indices(CI) of B.capitata,A.wrightii and E.guineensis were 7.29,20.24 and 75.00,respectively.The electrolyte leakage of leaves was measured in October and January under different temperatures,and the semi-lethal low temperature(LT_(50)) of leaves was assayed in different sampling periods by Logistic equation.The LT_(50) of B.capitata,A.wrightii and E.guineensis were-7.93,-5.03 and(-2.19℃) in October,and were19.10,-6.60 and-2.94℃ in January,respectively.The results indicate that the sequence of the cold tolerance is as follows: B.capitata A.wrightii E.guineensis.

通过测定厦门的三种棕榈植物布迪椰子、油棕和沼地棕的不同组分的热值和灰分含量.结果表明,布迪椰子各组分干重热值和去灰分热值由大到小的顺序为成熟叶＞细根＞幼叶＞粗根＞根茎＞叶柄;油棕的为成熟叶＞粗根＞细根＞幼叶＞叶柄＞根茎;沼地棕的为成熟叶＞粗根＞细根＞幼叶＞叶柄.布迪椰子的灰分含量高低顺序为细根＞粗根＞根茎＞幼叶＞叶柄＞成熟叶,油棕的为成熟叶＞幼叶＞细根＞粗根＞叶柄＞根茎;沼地棕的为幼叶＞成熟叶＞细根＞粗根＞叶柄.布迪椰子和沼地棕成熟叶的热值显著高于油棕,并且布迪椰子的成熟叶热值略低于沼地棕,但布迪椰子幼叶的热值显著高于沼地棕和油棕,布迪椰子的叶柄的热值显著低于沼地棕和油棕,说明耐寒性强的布迪椰子热值和灰分比耐寒性弱的油棕的分配策略更加合理,有利于提高其对低温的适应性,对植物引种具有重要的指导意义.

Seasonal changes of caloric value and ash content of Butia capitata were studied. The annual average caloric value was in the following order: mature leaves (20.65 kJ g-1) young leaves (19.84 kJ g-1) roots (19.55 kJ g-1) petioles (18.77 kJ g-1). The organs showed maximum gross caloric values (GCV) in autumn and minimum ones in winter. Ash free caloric values (AFCV) varied as same as gross caloric values (GCV). The annual average ash content followed the order: roots (5.14%) petioles (4.33%) young leaves (4.21%) mature leaves (3.97%). The ash content was lower in mature leaves, markedly decreased in young leaves during autumn, and then increased during winter. Seasonal changes of ash content in mature leaves were same with those in young leaves. Petioles had much lower ash content than roots during winter. Changes in ash content and caloric value of Butia capitata in different seasons were good energy use strategy for species with high cold resistance to adapt the low temperature.

The view that tannic compounds have the main function against the microbes including plant pathogenic microbes and non pathogenic microbes,The important factors that influence that ability of tannic compounds to microor-ganisms is the tannin polymer size.In practice,the toxicity of tannins is always dynamic.The tannin monomers polymer-ization can improve the toxification,while the tannin oligomers polymerization can lead to the detoxification.