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采用室内水培试验法,研究了铝处理对广西区2个优良桉树无性系(Eucalyptus grandis×E.urophylla No.9和E.urophylla No.4,分别记为G9、G4)根系及叶片内MDA含量的影响。结果表明:2个桉树无性系根内MDA含量均比叶内高;铝处理下,2个桉树无性系幼苗的MDA含量明显升高,G4根中MDA含量最高,达11.49μmol·g-1,根中MDA含量比叶中高,桉树无性系幼苗根部受铝伤害较叶严重。 相似文献
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Fett-Neto AG Fett JP Veira Goulart LW Pasquali G Termignoni RR Ferreira AG 《Tree physiology》2001,21(7):457-464
Adventitious rooting is essential for vegetative propagation of woody species. We studied the effects of auxin and light on the development of adventitious roots in cuttings obtained from seedlings of Eucalyptus saligna Smith and E. globulus Labill in an attempt to characterize the adventitious rooting process and identify factors controlling rhizogenesis. Root development was scored as rooting percentage, root density (roots per rooted cutting), mean rooting time and root length. In both species, rooting time was reduced in the presence of auxin. Cuttings from 2-month-old E. saligna seedlings were responsive to lower auxin concentrations than comparable cuttings from E. globulus seedlings. Cuttings from 3-month-old E. saligna seedlings rooted promptly and rooting was not significantly affected by light conditions. In contrast, rooting of cuttings from 3-month-old E. globulus seedlings exhibited recalcitrant behavior and no roots were formed if illuminated during the root formation phase. Effective root regeneration of E. globulus cuttings was obtained by a 4-day exposure to 10 mg l(-1) IBA and culture in darkness during the root formation step. Loss of rooting capacity with seedling age was more pronounced in E. globulus than in E. saligna. The possibility of switching adventitious rooting off and on by manipulating light regime and exogenous auxin supply in E. globulus, and the constitutive nature of rooting in E. saligna may provide useful models for examining the rooting process at the biochemical and molecular levels in Eucalyptus. 相似文献
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Silva IR Novais RF Jham GN Barros NF Gebrim FO Nunes FN Neves JC Leite FP 《Tree physiology》2004,24(11):1267-1277
Aluminum (Al) tolerance mechanisms in crop plants have been extensively researched, but our understanding of the physiological mechanisms underlying Al tolerance in trees is still limited. To investigate Al tolerance in eucalypts, seedlings of six species (Eucalyptus globulus Labill., Eucalyptus urophylla S.T. Blake, Eucalyptus dunnii Maiden, Eucalyptus saligna Sm., Eucalyptus cloeziana F. J. Muell. and Eucalyptus grandis w. Hill ex Maiden) and seedlings of six clones of Eucalyptus species were grown for 10 days in nutrient solutions containing Al concentrations varying from 0 to 2.5 microM (0 to 648 microM Al3+ activities). Root elongation of most species was inhibited only by high Al3+ activities. Low to intermediate Al3+ activities were beneficial to root elongation of all species and clones. Among the species tested, E. globulus and E. urophylla were more tolerant to Al toxicity, whereas E. grandis and E. cloeziana were more susceptible to Al-induced damage. Although E. globulus seedlings were tolerant to Al toxicity, they were highly sensitive to lanthanum (La), indicating that the tolerance mechanism is specific for Al. Fine roots accumulated more Al and their elongation was inhibited more than that of thick roots. In E. globulus, accumulation of Al in root tips increased linearly with increasing Al concentration in the nutrient solution. The majority of Al taken up was retained in the root system, and the small amounts of Al translocated to the shoot system were found mainly in older leaves. No more than 60% of the Al in the thick root tip was in an exchangeable form in the apoplast that could be removed by sequential citrate rinses. Gas chromatography/mass spectrometry and ion chromatography analyses indicated that root exposure to Al led to a greater than 200% increase in malic acid concentration in the root tips of all eucalypt species. The increase in malate concentration in response to Al treatment correlated with the degree of Al tolerance of the species. A small increase in citric acid concentration was also observed in all species, but there were no consistent changes in the concentrations of other organic acids in response to Al treatment. In all eucalypt species, Al treatment induced the secretion of citric and malic acid in root exudates, but no trend with respect to Al tolerance was observed. Thus, although malate and citrate exudation by roots may partially account for the overall high Al tolerance of these eucalypt species, it appears that tolerance is mainly derived from the internal detoxification of Al by complexation with malic acid. 相似文献
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经过近100年的引种历史,四川共收集了130余种桉树,目前仍保留有近40种桉树。这些树种在四川省的林业建设中发挥了重要作用。在四川具有发展前途的桉树有:巨桉、直干兰桉、柳桉、史密斯桉、邓恩桉、迪恩桉、亮果桉、赤桉、大花序桉、尤曼桉等。根据桉树生物学特性以及四川多年来桉树栽培情况,将四川桉树栽培地区划分为盆地、攀西河谷阶地和干热河谷等三个栽培区。针对不同的栽培区,提出相应的适宜桉树种,并对巨桉、直干蓝桉、赤桉树种不同培育目标的栽培技术进行了总结。 相似文献
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通过对两种1年生桉树无性系(巨细桉DH201-2与尾巨桉DH32-29)6种林分密度(1250株.hm-2、1667株.hm-2、2500株.hm-2、5000株.hm-2、6667株.hm-2、10000株.hm-2)进行生长量、根系和风害的调查,并分析林分密度、生长量和根系与抗风性相关性,结果表明:DH201-2以林分密度1667株.hm-2的生长量最大,而DH32-29胸径和冠幅以1667株.hm-2最大、树高以5000株.hm-2的最高;两个无性系间各个密度生长量差异显著;DH201-2以密度2500株.hm-2的抗风性最好,DH32-296个密度的抗风性均较差;相同林分密度下DH201-2根总数与根直径在0~2cm的根数显著比DH32-29多,DH32-29冠幅显著比DH201-2大,因此DH201-2易断干,而DH32-29易倒伏;相同林分密度下DH201-2比DH32-29抗风性强。 相似文献
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尾巨桉扦插繁殖技术研究 总被引:5,自引:1,他引:4
根据当前尾巨桉苗木急需而种子繁殖易产生分化的现状,开展了尾巨桉扦插繁殖技术研究。结果表明:采用轻基质与红心土各半混合作为尾巨桉扦插的基质能提高扦插生根率和苗木生长量;尾巨桉嫩枝扦插其生根率高于硬枝;质量分数为5.0×10-4的ABT-1生根剂能大幅度提高尾巨桉的扦插生根率。 相似文献
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《林业研究》2020,31(4)
Camptotheac acuminata Decne is a unique tree species in China with an important secondary metabolite,camptothecin(CPT),used in the treatment of cancer.Nitrogen(N) is an important element that affects plant growth and the accumulation of CPT.Reports on the effect of N on CPT synthesis from a genetic perspective are scarce.To explore the effects of different N sources and levels on CPT synthesis in C.acuminata,two-year-old seedlings were fertilized with different concentrations of pure ammonium sulphate,source of ammonium N(NH_4~+-N),and potassium nitrate for nitrate N(NO_3~--N).Concentrations of 2.5,5,7.5,and10 g pot~(-1) NH_4~+-N and NO_3~--N were used.The results showed that 7.5 g NH_4~+-N and NO_3~--N treatments were best for growth and fresh weight of leaves.Compared with the other treatments,the CPT content,tryptophan synthase and tryptophan decarboxylase activities,and expression of the CaTSB and CaTDCl genes under the 2.5 g NH4+-N and NO_3~--N treatments peaked significantly at 30 days.However,the expression of CaTDC2 surpassed that of the other two genes at 60 days.Therefore,compared with NH4+-N source,the NO_3~--N source was more beneficial for growth,and NO_3~--N was better for CPT yield.Consequently,leaves of C.acuminata treated with 2.5 g NO_3~--N could be harvested after 30 days to obtain maximum CPT content.CaTDC1 is more closely linked to CPT synthesis.The results of this study improved the production of CPT in C.acuminata via fertilization. 相似文献
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韶关市6个桉树无性系试验初报 总被引:1,自引:1,他引:0
通过对参试的尾巨桉(DH.33.27、DH.33.29、广林9号)、尾赤桉(201号、201.2号)和尾叶桉(U6)6个桉树无性系早期人工林的生长量和抗逆性进行调查和综合评价。结果表明:参试无性系20个月生林分平均胸径6.30~7.72cm,平均树高为5.87~9.18m,都表现出速生特性。6个无性系间的树高生长存在极显著差异,胸径生长量存在显著差异。尾赤桉和尾巨桉5个无性系间树高生长也存在极显著差异,胸径生长量差异不显著。尾叶桉U6和尾巨桉DH.33.29耐寒性较差,尾赤桉系列幼龄林存在易风倒现象。尾巨桉系列(DH-33-27、广林9号)速生性、适应性较强,可作为目前韶关市桉树人工林建设的主栽品种。 相似文献
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文章通过单项选择法和双向选择法对14种速生桉人工林心材的抗家白蚁(Coptotermes formosanus)蛀蚀性进行室内测试,比较各种桉树心材被白蚁蛀蚀程度及质量损失率,以评价各种桉树木材对家白蚁的抗蚁蛀性能.单项选择测试结果表明,不同桉树心材抵抗家白蚁的蛀蚀能力有很大差异,20 a生韦塔桉(Eucalyptus wetarensis)和14 a生细叶桉(E.tereticornis)心材对家白蚁的天然抗蛀性最强,平均质量损失率均小于10%,属于轻微蛀蚀等级;50 a生窿缘桉(E.exserta)和40 a生柠檬桉(E.citriodora)次之,平均质量损失率在10%~20%,属于轻度至中度蚁蛀等级;8 a生巨桉(E.grandis)的抗蚁蛀性能最差,平均质量损失率大于50%,属于严重蛀蚀等级;其余8种桉树心材包括蓝桉(E.globulus)、 赤桉(E.camaldulensis)、 粗皮桉(E.pellita)、 托里桉(E.torelliana)、 刚果12号桉(E.ABL12)、 尾叶桉(E.urophylla)、 尾巨桉(E.urophylla×E.grandis)和尾细桉(E.urophylla×E.tereticornis),年龄为6~28 a,平均质量损失率为30%~40%,属于中度至严重蛀蚀等级.双向选择测试结果表明,家白蚁对不同桉树心材有取食偏爱性,14种桉树心材被家白蚁取食喜好优先排序为:巨桉→托里桉→尾细桉→蓝桉→刚果桉12号→粗皮桉→尾叶桉→尾巨桉→柠檬桉(28 a生)→柠檬桉(40 a生)→赤桉→窿缘桉→细叶桉→韦塔按. 相似文献
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本文对9个尾叶桉、巨尾桉、尾巨桉无性系0.5~2.5年生试验林生长率、差异性及林分直径结构分析,发现林龄0.5~1.5 a是无性系树高生长高峰期,此时树高生长率达79.20%~96.27%,是林龄1.5~2.5 a树高生长率的3~4倍;林龄1.5~2.5 a时,各无性系林分胸径、树高、单株材积生长率分别为19.66%~25.67%、18.58%~27.96%、52.57%~62.54%,生长率最大的是E7号无性系(胸径、单株材积)和E6号无性系(树高);秩次相关分析表明:各无性系胸径、单株材积生长量在不同林龄时排序变动不大,而无性系树高生长量排序在不同林龄时变动较大;差异性分析表明:无性系间胸径、树高、单株材积生长差异显著,但随林龄增加有差异减小趋势;林龄2.5年生时,E5号无性系胸径、单株材积生长量最大,分别达11.39 cm、0.0736 m3;各无性系林分树木径阶范围为6~14 cm或8~14 cm,以10 cm或12 cm径阶树木占最大比例,除E8号无性系外,其余8个无性系树木径阶分布总体上近似正态分布。 相似文献
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对雷州半岛6年生11种桉树无性系的林分生长量、生物量、炭化量进行了研究。结果表明:11种桉树无性系林分蓄积量大小排序为:GL4>GL9>DH32-22>LH5>DH201-2>LH1>M1>EC34>柳桉1>UC184-1>SH7,林分蓄积量最大的GL4是最小的SH7的2.12倍。11种桉树无性系各组分生物量变化不一致,但都以树干的最大,叶片的最小。LH5和GL4的林分生物量最大,均高于180t·hm-2,SH7和UC184-1林分生物量较小,均低于130t·hm-2,其它几种较为平均,在140~170t·hm-2之间。11种桉树无性系炭化量受林分生物量和炭化率影响,林分生物量和炭化率越大,炭化量越大。LH5、DH201-2、LH1和GL4的炭化率较高,均大于20%,UC184-1和SH7的炭化率最低。11种桉树无性系中LH5林分生物量最大,炭化率最高,故炭化量最高;其次为GL4和LH1,其炭化量均高于60t·hm-2,EC34、GL9、柳桉1、M1和DH32-22均大于50 t·hm-2,UC184-1的炭化量低于40 t·hm-2为最低。综合生长量、生物量和炭化率分析,GL4、LH5、GL9和DH32-224个无性系为一类,可作为薪炭林品系发展;LH1、EC34、DH201-2和M14个无性系划分为一类,作为薪炭林发展潜力较低;柳桉1、UC184-1和SH73个无性系为一类,不适合作为薪炭林发展。 相似文献
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巨桉无性系生长早期选择 总被引:1,自引:0,他引:1
对26个巨桉无性系人工林生长性状的调查分析表明:胸径、材积在无性系间呈极显著差异,相关性分析结果表明胸径、树高、材积三者间存在极显著的正相关关系。变异系数最大的是材积,达到78.82%,其次为树高和胸径,分别为52.23%、23.13%。胸径、树高、材积的重复力分别为0.5744、0.5469、0.3453。利用综合评定方法评选出5个优良的巨桉无性系,分别为20、18、25、9和5号。5个优良无性系胸径、树高、材积的遗传增益分别为11.60%、11.09%和2.05%。 相似文献
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以巨尾桉(Eucalyptus grandis×Eucalyptus urophylla)为试验材料,研究不同浓度水杨酸(SA)诱导桉树对焦枯病抗性与叶绿素荧光参数的关系。结果表明,SA能降低Fo值,提高Fm、Fv值,表现为先上升后下降的变化趋势。SA处理的桉树叶片Fv/Fo、Fv/Fm值,第3天达到最大值,说明SA 1~3 mmol.L-1处理的抗焦枯病的持久期为3 d。SA 1 mmol.L-1处理的桉树叶片Fo值最小,Fm、Fv、Fv/Fo和Fv/Fm值最高;说明SA 1mmol.L-1处理的效果最好,能有效地减轻光合机构的损伤,一定程度上抑制焦枯病菌的侵害。 相似文献