千年桐(Aleurites montana)人工林细根特征及其与细根N、C含量的关系

采用完整土块法,以千年桐（Aleurites montana）人工林为研究对象,测定了1~5级细根的形态、生物量和组织碳（C）、氮（N）含量,分析了不同径级和序级与细根形态指标的差异性,对序级与细根生物量、碳氮含量及它们之间的关系进行探讨。结果表明：直径≤1 mm的细根根尖数、根系累计长度、根系累计表面积分别占据总量的99.66%,88.42%,69.82%;随着根序从1级根到5级根升高,千年桐细根直径由0.86 mm增加到1.35 mm,组织密度由0.11 g/cm3上升到0.47 g/cm3,根表面积密度由0.46 m2/m3降低到0.085 m2/m3,比根长由32.04 m/g减少到16.41 m/g;千年桐细根直径、比根长、根表面积密度、根组织密度及生物量与序级之间回归分析发现它们与序级之间具有二次函数、指数函数、线性函数、三次函数及高斯峰值函数关系;1~5级细根生物量对总生物量的贡献分别为：18.7%,30.9%,27.1%,16.6%,6.7%;N含量随着根序升高由16.73 mg/g下降到11.83 mg/g,C含量则由454.97 mg/g上升到494.43 mg/g;千年桐细根C/N比的变异受根组织N含量的影响程度达到93%,而受C含量的影响程度仅为50%。上述结果证明,千年桐细根的结构特征、生物量和碳氮含量之间存在密切联系,为了解千年桐根系结构与功能提供重要依据。

Monthly variation in litterfall and the amount of nutrients in an Aleurites montana plantation

In this study, the dynamics of monthly variation in litterfall and the amount of nutrients, i.e., organic C, N, P and K, in an Aleurites montana plantation were analyzed, based on a field study and experiments over one year. The results show that the litterfall mass of A. montana collected generally presents an ascending trend with maximum defoliation occurring in the autumn and winter （October-December）, accounting for 75.67% of the total amount of annual litterfalk The sequence in the amount of nutrients in A. montana litter was as follows： organic C 〉 N 〉 K 〉 P; their monthly amounts show various dynamic curves. Similar to the dynamics of the mass of monthly litterfall, the monthly returns of C, N, P and K generally show an ascending trend with their peak values all occurring in December. The mass of A. montana litterfall and the dynamics of its monthly nutrient return provide, to a certain degree, a scientific reference for planting and fertilizing A. montana.

Origin of Little Missouri River - South Fork Grand River and nearby Drainage Divides in Harding County, South Dakota and Adjacent Eastern Montana, USA

Barbed tributaries flowing in southeast directions, an asymmetric drainage divide with both the South Fork Grand River and the North Fork Moreau River, and the Jump-off escarpment-surrounded basin (interpreted here to be a large abandoned headcut) are examples of topographic map evidence suggesting the north oriented Little Missouri River valley eroded headward across a large southeast oriented anastomosing complex of ice-marginal melt water flood flow channels that once crossed Harding County, South Dakota. Additional evidence includes southeast oriented tributaries to the northeast oriented South Fork Grand River and multiple divide crossings (e.g. through valleys and wind gaps) on the Boxelder Creek-Little Missouri River divide (in eastern Montana and west of the Little Missouri River) and suggests deep regional erosion occurred as the north oriented Little Missouri River valley eroded headward into and across the region. Harding County is located south and west of the southwest limit of coarse-grained glacial erratic material and ice-marginal melt water flow routes logically should have crossed it. Deep melt water erosion of Harding County and adjacent eastern Montana regions to the west is not consistent with many previous drainage history and glacial history interpretations, but is consistent with deep erosion by continental ice sheets.

Anti-lipid droplets accumulation effect of Annona montana(mountain soursop)leaves extract on differentiation of preadipocytes

The Annona genus is a member of Annonaceae,one of the largest families of plants across tropical and subtropical regions.This family has been used in several ethnomedicinal practices to treat a multitude of human diseases.However,the molecular mechanism underlying its effect on the lipid droplet formation and on the expression of adipogenic markers of this plant remain to be investigated.In this study,we examined whether the extracts from the aerial part of Annona montana affect in vitro differentiation of preadipocytes.For our investigations,both mouse embryo fibroblast 3T3-L1 and normal human primary subcutaneous preadipocytes were incubated with Annona montana extracts(-and its subfractions-)and then analyzed on preadipocyte differentiation,lipid content,lipid droplet size and number,the expression of adipogenic-specific transcriptional factors,as well as cell survival.From our examinations,we found the Annona montana ethyl acetate extract to exhibit a potent inhibitory effect on adipogenesis,without affecting cell survival,in a dose-dependent manner.Such inhibitory effects included a significant decrease in the accumulation of lipid content by both a dramatic reduction of size and number of lipid droplets.This extract strongly attenuated the expression of PPARγand HMGB2.It also inhibited the expression of CEBPα,FAS,and Akt without influencing Erk1/2 activities.Our findings suggest that specifically,the Annona montana ethyl acetate extract has a prominent inhibitory effect in cellular pathways of adipocyte differentiation by modulating specific gene expression,which is known to perform a pivotal role during adipogenesis.

Upper Sun River Drainage Basin Origin Determined by Topographic Map Interpretation Techniques: Lewis and Clark and Teton Counties, Montana, USA

A new and fundamentally different regional geomorphology paradigm in which massive south- and southeast-oriented meltwater floods flowed across the entire Missouri River drainage basin is tested by interpreting detailed topographic maps of the Montana upper Sun River drainage basin region by trying to explain origins of previously unexplained or poorly explained erosional landforms located upstream from Sun River Canyon (which cuts across Montana’s north-to-south oriented Sawtooth Range). Mountain passes, through valleys, and other drainage divide low points along what are today high mountain ridges, including the North American east-west continental divide, are interpreted to be evidence of drainage routes that once crossed the region. These drainage divide crossings suggest that prior to erosion of present-day upper Sun River drainage basin valleys, massive floods moved in south directions across what are today the north-oriented Middle and South Fork Flathead River drainage basins into today’s upper Sun River drainage basin area and carved a complex of diverging and converging channels into what was probably a low relief surface now represented by the crests of the region’s highest mountain ridges. Further, the map evidence shows how a diverging complex of south- and southeast-oriented upstream Sun River drainage basin flood flow channels changed flow direction to cross the Sawtooth Range in a northeast direction before converging on the Montana plains at a location downstream from Sun River Canyon. The observed upper Sun River drainage basin area topographic map evidence is consistent with the new geomorphology paradigm predictions, in which massive south-oriented meltwater floods flowing across the rising rim of a continental ice sheet created deep “hole” (created by deep ice sheet erosion and ice sheet weight caused crustal warping) are diverted to flow in northeast and north directions into and across deep “hole” space being opened up by ice sheet melting.

Antibacterial Effect of the Essential Oils Extracted From Ruta chalepensis L. and Ruta montana （L.） L.

Ruta genus is a member of the family Rutaceae that has been cultivated widely in many regions of the world because of its medicinal properties. In Tessala Mountain （Sidi Bel Abbes Country, North-Western of Algeria）, the Ruta genus commonly known by ＂fidjel＂ is represented by two species： Ruta Chalepensis L. and Ruta Montana （L.） L. frequently used by local population in a traditional treatment. The water-distilled essential oils from this species yielded 7.23% and 6.104% for Ruta chalepensis L. and Ruta montana （L.） L. respectively. The essential oil of Ruta montana （L.） L. showed a strong antibacterial activity against all bacterial strains tested （Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Mycobacterium kansasii ATCC ! 2478 and Mycobacterium vaccae ATCC 1548314） compared to Ruta chalepensis L. oils which have a moderate effect only on Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Therefor, the antibacterial properties of the essential oils of Ruta Chalepensis L. and Ruta Montana （L.） L. are now well established through this study and therefore could justify their future uses in the treatment of nosocomial infections.

An in vitro evaluation of the antioxidant and antidiabetic potential of Sutherlandia montana E. Phillips & R.A. Dyer leaf extracts

Objective: To evaluate the antioxidant and antidiabetic activities of Sutherlandia montana E. Phillips & R.A. Dyer leaf extracts using the in vitro model.Methods: The antioxidant activities of aqueous, decoction, ethanol and hydro-ethanol extracts of the plant were determined using seven different assays; the antidiabetic potential was evaluated through the inhibition of key carbohydrate hydrolysing enzymes(aamylase and a-glucosidase), while the modes of the enzymes inhibition were assessed using enzyme kinetic analysis.Results: The ethanol extract exhibited the best scavenging activity(IC_(50): 0.47, 0.36,0.20, 0.29 and 0.01 mg/m L) against the tested radicals like 1,1-diphenyl-2-picrylhydrazyl,2, 20-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), nitric oxide, hydroxyl and superoxide anion, respectively. It also showed the best reducing power efficiency when compared with the standard(silymarin), while the decoction extract displayed the strongest metal chelating potential(IC_(50): 0.71 mg/m L). The ethanol(IC_(50): 5.52 mg/m L)and decoction(IC_(50): 0.05 mg/m L) extracts exhibited mild and strong inhibitory effects on the specific activities of a-amylase and a-glucosidase respectively, through an uncompetitive and non-competitive mode of action.Conclusions: The observed properties might be linked to the presence of active principles as shown by the results of the phytochemical analyses of the extracts. This research has validated the folkloric application of Sutherlandia montana as a potential antidiabetic agent, which is evident from the inhibition of specific activities of key enzymes involved in carbohydrate metabolism.

Cultivation characteristics and flavonoid contents of wormwood (Artemisia montana Pamp.)

The aim of this study was to establish the optimum harvesting time and the content of flavonoids in the leaves, stems, and roots of Artemisia montana Pamp. A. montana was monitored from June to October in 2012. The yield of A. montana at high density (30 × 10 cm) was higher than that of A. montana at low density (30 × 20 and 30 cm). Yield in terms of dry weight was increased with an extended growth period and development stage. High yield achieved at 2580 and 2757 kg?10 a?1 in September and October, respectively. Among the leaves, stems, and underground plant organs, jaceosidin and eupatilin were mainly detected in the leaves, and the highest levels were observed in June, at values of 66.6 and 158.2 mg?100 g?1, respectively. In contrast, apigenin was the major compound detected in the underground plant organs, with levels ranging from 21.2 to 29.5 mg?100 g?1 until September. Therefore, optimal harvest times were between September and October, generating a high yield and adding economic value although a higher level of total flavonoids was observed in crops harvested in June.

Glycosidically Bound Volatile Compounds of Satureja montana L.,S.cuneifolia Ten.,S.subspicata Vis.and Endemic S.visianii SiliC

In this paper, the glycoconjugated volatile compounds of four Croatian Satureja species (Satureja montana L., S. cuneifolia Ten., S. subspicata Vis. and endemic S. visianii Silic) were investigated. Content and composition of these compounds were examined depending on the stage of plant development. GC and GC–MS analysis of volatile aglycones revealed twenty-one compounds. Thymoquinone, geraniol and carvacrol were detected in all vegetative phases of the investigated plants. Other quantitatively important aglycones were eugenol and thymol of S. montana, phenyl ethyl alcohol, benzene acetaldehyde, borneol, α-terpineol, thymol and eugenol of S. cuneifolia, phenyl ethyl alcohol, benzene acet-aldehyde, terpinen-4-ol, α-terpineol and β-ionone of S. subspicata and camphor, thymol and 8a-acetoxylemolol of S. visianii. Moderate similarity in the chemical composition of essential oils and volatile aglycones of investigated plant species indicate that many biologically active compounds are glycosylated and accumulate as non-volatile glycosides.

氮、磷、钾配施对葛根生长及品质的影响

为探明氮、磷、钾肥配施对葛根生长及品质的影响,为葛根高效栽培提供合理的施肥技术支撑和理论依据,采用L_(9)(3~4)正交试验设计,研究氮、磷、钾配施对葛根产量和主要功能成分的影响,明确研究区葛根氮、磷、钾的最佳施用量。结果表明,不同施肥方案对葛根产量和功能成分的影响显著,其中以N_(3)P_(1)K_(2)(N 270kg/hm^(2),P_(2)O_(5)45 kg/hm^(2),K_(2)O 90 kg/hm^(2))处理的产量和总黄酮含量最高,分别为2.13 kg/株和83.10 mg/g;N_(1)P_(3)K_(2)(N 90 kg/hm^(2),P_(2)O_(5)135 kg/hm^(2),K_(2)O 90 kg/hm^(2))的葛根素含量最高,为24.85 mg/g,N_(1)P_(2)K_(3)(N 90 kg/hm^(2),P_(2)O_(5)90 kg/hm^(2),K_(2)O 135 kg/hm^(2))处理的大豆苷和大豆苷元含量均为最高,分别为22.96和2.55 mg/g。氮、磷、钾肥配施对葛根产量和葛根素含量影响的大小顺序为氮肥>钾肥>磷肥。以葛根产量为目标的最佳施肥量为N 270 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2),以葛根品质提升为目标的最佳施肥量为N 180 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2)。

千年桐雌雄植株花期生理生化差异分析

为揭示千年桐雌雄植株之间的差异,分别以处在花期的雌雄植株叶片为试材,采用乙醇浸提法、蒽酮比色法、福林试剂测定法、氮蓝四唑法、愈创木酚法、酶联免疫吸附法,比较测定叶片叶绿素、可溶性糖、总酚含量,超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性以及内源激素含量差异。结果表明,千年桐植株叶片叶绿素a、叶绿素b、叶绿素总量、可溶性糖、总酚的含量均表现为雌株高于雄株,但差异不显著(P>0.05)。雄株叶片过氧化物酶(POD)活性、ZR和IAA含量均显著高于雌株(P<0.05),这几个指标与千年桐性别关系密切。

镉胁迫下不同地方品种粉葛的镉积累特性及产量差异

为探究在镉胁迫下不同粉葛品种对镉吸收转运及产量的影响,在镉地质高背景农田土壤中,以粉葛不同品种为对象,采用田间试验,研究7个地方品种粉葛的镉积累特性和产量差异。结果表明,在土壤镉胁迫下,不同品种不同部位镉含量表现为芦头>主藤>叶片>块根皮>块根;芦头和块根皮的品种间差异总体大于其他部位,不同品种的块根镉含量最小,为0.24 mg/kg,均超过国家块根类蔬菜规定的限量值(0.10 mg/kg);合水粉葛芦头和主藤较易于富集镉,细叶粉葛块根皮对镉的阻隔积蓄能力最强,桂粉葛1号和细叶粉葛块根积累镉的含量相对较低且种植经济效益也优于其他品种。

铝胁迫下千年桐内生真菌对根际土壤不同铝形态的影响

【目的】了解不同浓度铝胁迫下内生真菌对根际土壤不同铝形态的影响。【方法】将5种分离自千年桐的优势内生真菌菌株配置为菌液,分别施入不同浓度铝胁迫的千年桐盆栽苗,外源铝浓度设置为0 mmol/L (A0)、0.555 mmol/L (A1)、0.745 6 mmol/L (A2)、1.111 mmol/L (A3)和1.852 mmol/L (A4)。通过测定不同菌液处理的土壤活性铝含量以及千年桐根系活力,探讨内生真菌对根际土壤活性铝含量及比例变化的影响。【结果】在非铝胁迫(A0)的条件下,不同内生真菌对千年桐根际土壤活性铝含量均有不同程度的升高。施加链格孢属菌液处理后,根际土壤交换性铝含量在A2铝浓度时较未施菌处理降低了20.58%,单聚体羟基铝含量在各铝浓度下均低于未施菌处理,降幅分别为7.19%(A1)、19.56%(A2)、6.27%(A3)和4.01%(A4)。盾壳霉属和嗜热真菌属菌液处理后,千年桐根际土壤活性铝含量均高于未施菌处理。不同菌液处理对千年桐根系活力的作用各异,其中盾壳霉属处理后的根系活力较未施菌提升了11.27%,而拟盘多毛孢属处理后根系活力与未施菌处理无显著差异。【结论】接种内生真菌能改变植株根际土壤活性铝含量和比例。链格孢属能有效降低根际土壤单聚体羟基铝含量,而盾壳霉属和嗜热真菌属提升了根际土壤活性铝含量。内生真菌的作用效果受到铝浓度、内生真菌基因型和宿主种类的影响。研究结果拓展了内生真菌对于宿主根际土壤影响的探索,可为林木-微生物互作的深入研究提供参考。

铝胁迫下千年桐叶片角度及形态特征的变化

高等植物通过调整叶角大小,在弱光条件下提高光利用效率或者在光辐射强烈时有效避免强光的伤害,以此获得适度光照或者减弱叶片受到的光胁迫,促进植株生长。但胁迫条件会对叶片的适光行为产生不同程度的影响。为探究铝胁迫对红壤区常见生态树种千年桐叶片形态和行为调整的影响,以1年生千年桐苗木为试验材料,设置无铝0 mmol·L^(-1)(CK)、低铝0.555 mmol·L^(-1)(T1)、中铝0.746 mmol·L^(-1)(T2)、高铝1.111 mmol·L^(-1)(T3)4种不同浓度铝处理,比较不同浓度铝胁迫下,千年桐苗木的叶角度、叶片形态特征以及光合生理指标的差异,分析影响叶角变化的相关因子,从叶片形态可塑性和适光行为调整的角度揭示千年桐对铝胁迫的响应。结果表明,光照充足条件下,CK处理的千年桐叶片悬挂角在7:30时最小(106.00°),叶脉处于近水平位置,随着光照的增加叶悬挂角有所增大;不同铝浓度处理下叶悬挂角与叶方向角的日变幅按从小到大的排序均表现为T2<T3<CK<T1。在T1和T3处理时千年桐叶长、叶宽、叶柄长与叶面积下降明显,叶形指数在T3处理时达到最大值。千年桐叶片的净光合速率和蒸腾速率在T2处理时数值最小,与CK相比,其降幅分别为32.35%和46.22%;瞬时水分利用效率在T2处理下达到最大值。相关性分析显示,千年桐叶方向角与叶柄长度呈与叶形指数呈显著负相关;叶悬挂角与叶方向角呈显著负相关。由此可知,无铝胁迫时千年桐在强光条件下能通过减小叶方向角和增大叶悬挂角,降低叶面对光辐射的截获量以避免光损伤;在弱光条件下通过增大叶方向角和减小悬挂角使叶片两面能接受更多的光辐射。低铝浓度下,千年桐仍可进行积极的叶片适光调整。而中高铝浓度下,千年桐叶角变幅减小,但可通过光合生理指标的调整降低叶片失水量,实现叶柄对叶片角度的调节。

Montana Duck Hunters

Ten Montana hunters are in a duck blind when 10 ducks fly over.All 10 hunters pick a duck at random to shoot at,and all 10 hunters fire at the same time.How many ducks could be expected to escape,on average。

抚育间伐对福建千年桐-闽楠混交林磷含量的影响

明确抚育间伐对千年桐-闽楠混交林的磷动态结构干扰机制,为千年桐-闽楠混交林土壤磷素的科学管理提供依据。以福建南平范桥国有林场5 a生千年桐和闽楠为对象,测定其土壤全磷、有效磷含量以及枝、叶、干、根全磷含量,研究抚育间伐对其根际土和营养器官磷含量的影响。结果表明:1)千年桐与闽楠根际磷富集作用明显,其抚育间伐前后根际土全磷和有效磷含量均显著高于非根际土(P<0.05),抚育间伐使千年桐和闽楠根际土全磷和有效磷含量得到显著提高(P<0.05),在0~15 cm土壤深度,随着土壤深度增加,千年桐和闽楠根际土全磷和有效磷含量均呈上升的趋势。2)千年桐不同土壤深度根际土全磷与有效磷含量在抚育间伐前后均高于闽楠,抚育间伐后千年桐与闽楠不同土壤深度根际土全磷含量的差值与有效磷含量的差值均增大,抚育间伐提高了千年桐与闽楠枝、叶、干、根全磷含量,在抚育间伐前后,千年桐枝、叶、干、根全磷含量均高于闽楠。3)相关性分析表明,千年桐和闽楠根际土有效磷与根全磷、叶全磷均为显著正相关(P<0.05),其根全磷与叶全磷也显著正相关(P<0.05)。抚育间伐提高了千年桐和闽楠营养器官与根际土磷含量,对非根际土磷含量影响较小,对千年桐和闽楠根际土壤磷活化吸收有促进影响;抚育间伐对千年桐的影响程度大于闽楠,千年桐根系比闽楠更发达,具有更强的土壤磷活化能力。

林分改造后的水土保持林地土壤的持水性能

[目的]研究林分改造后的林地水文生态特征,分析水土保持林的持水特性,为南方红壤水土流失区的生态治理、植被恢复以及树种配置提供参考。[方法]选择福建省长汀县红壤侵蚀区松林改造后营造的千年桐生态林作为研究对象,以林外草坡作为对照,比较千年桐生态林和草坡的枯落物持水性能指标之间的差异,同时测定千年桐林分0—60 cm不同土层土壤物理性质,并利用隶属函数对林地持水性能进行综合评价。[结果]千年桐枯落物持水量始终高于对照,浸水前为对照的1.15倍,浸水24 h后为对照的2.10倍;浸水0.25 h时,千年桐和对照的枯落物吸水速率分别为1723.64,700.8 mm/h。千年桐林地的枯落物累积量、枯落物最大持水量、枯落物有效拦蓄量均显著高于对照。林地0—10 cm土层的土壤容重显著低于其他土层,而最大持水量、毛管持水量、田间持水量、毛管孔隙度和总孔隙度均显著高于其他土层;0—20 cm土层的土壤有效蓄水量和有效水储量显著低于20—60 cm土层。林地持水性能的综合评价结果表明土壤毛管孔隙度的综合评价值较高,而土壤自然含水率的综合评价值较低。[结论]千年桐生态林枯落物持水性能较好,土壤通气、透水性较高。从林分综合评价来看,与土壤孔隙度,特别是毛管孔隙度相关的指标对于提高千年桐生态林持水性能具有重要影响。

Plant functional traits and microbes vary with position on striped periglacial patterned ground at Glacier National Park, Montana

The retreating snowfields and glaciers of Glacier National Park, Montana, USA, present alpine plants with changes in habitat and hydrology. The adjacent and relic periglacial patterned ground consists of solifluction terraces of green, vegetation-rich stripes alternating with sparsely vegetated brown stripes. We established georeferenced transects on striped periglacial patterned ground for long-term monitoring and data collection on species distribution and plant functional traits at Siyeh Pass and at Piegan Pass at Glacier National Park. We documented species distribution and calculated the relative percent cover(RPC) of qualitative functional traits and used 16 S rRNA from soil samples to characterize microbial distribution on green and brown stripes. Plant species distribution varied significantly and there were key differences in microbial distribution between the green and brown stripes. The rare arctic-alpine plants Draba macounii, Papaver pygmaeum, and Sagina nivalis were restricted to brown stripes, where the RPC of xeromorphic taprooted species was significantly higher at the leading edge of the Siyeh Pass snowfield. Brown stripes had a higher percentage of the thermophilic bacteria Thermacetogenium and Thermoflavimicrobium. Green stripes were co-dominated by the adventitiously-rooted dwarf shrubs Salix arctica and the possibly N-fixing Dryas octopetala. Green stripes were inhabited by Krummholz and seedlings of Abies lasiocarpa and Pinus albicaulus. Prosthecobacter, a hydrophilic bacterial genus, was more abundant on the green stripes, which had 6,524 bacterial sequences in comparison to the 1,183 sequences from the brown stripes. While further research can determine which functional traits are critical for these plants, knowledge of the current distribution of plant species and their functional traits can be used in predictive models of the responses of alpine plants to disappearing snowfields and glaciers. This research is important in conservation of rare arctic-alpine species on periglacial patterned ground.

千年桐苗期生长和光合性能的种源分化及综合评价

为考察千年桐生长和光资源利用性的种源差异,于2019年在福建省南平市建阳区漳墩林业站千年桐种源育苗基地,以栽植于同质园环境的14个种源1年生千年桐苗木为试验材料,比较各种源苗木的高径、生物量、壮苗指数等生长指标,以及气体交换参数、叶绿素荧光特性、叶绿素含量等光合生理指标的差异和种源内与种源间的变异程度;并基于模糊隶属函数对不同种源千年桐进行综合评价。结果表明:不同种源千年桐的生长和光合生理特性存在显著差异,且这些指标的变异总体以种源间差异为主;其中龙岩新罗区、上杭和长汀种源的苗木高径、生物量和壮苗指数等生长指标总体优于其它种源;上杭种源的净光合速率最大,宁德蕉城区种源的水分利用率最大,而龙岩新罗区种源同时具有高光效、高水分利用率的光合生理特性;长汀和尤溪种源的F_(v)/F_(m)、F_(m)以及叶绿素总量均较高。对不同种源千年桐苗木的综合评价结果表明:龙岩新罗区、闽侯、上杭、长汀、南平建阳区、尤溪种源苗木的综合评价相对较好,可在福建闽北造林时予以优先考虑。研究结果可为千年桐优良种源的早期评价、筛选和推广及良种选育和科学栽培提供参考。

不同基质对千年桐容器苗光合生理特征的影响

于2019—2020年,在福建省南平市建阳区国营苗圃,采用9种基质配方,探讨不同基质对千年桐容器幼苗光合生理特性的影响。结果显示,千年桐苗木在P5(泥炭50%+黄心土25%+谷壳25%)基质培育的容器苗的净光合速率、蒸腾速率、水分利用效率均最高,P_(3)(泥炭30%+黄心土50%+谷壳20%)基质培育的千年桐容器苗的气孔导度最大且显著高于CK(黄心土基质),P_(4)(泥炭60%+黄心土20%+谷壳20%)基质培育的千年桐容器苗的胞间二氧化碳浓度和Fv/Fm最高。综合各指标特征来看,以泥炭50%+黄心土25%+谷壳25%以及泥炭60%+黄心土20%+谷壳20%这2种基质配方最有利于提高千年桐的光合能力。本研究结果可为千年桐容器育苗生产应用提供参考。