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1.
Species of Cephalostachyum Munro (Poaceae: Bambusoideae) from China are distributed in Yunnan and Tibet, mainly in Yunnan. In this paper, we discussed species of Cephalostachyum and compiled a key to species from China, based on recent studies on micromorphological characters of leaf epidermis and molecular phylogenetics of paleotropical woody bamboos. There is a total of seven species of Cephalostachyum distributed in China, all in Yunnan: Cchinense (Rendle) DZ. Li et HQ. Yang, Cfuchsianum Gamble et Hook. f., Cmannii (Gamble) Stapleton et DZ. Li, Cpallidum Munro, Cpingbianense (Hsueh et YM. Yang ex Yi et al.) DZ. Li et HQ. Yang, Csanguineum (WP. Zhang) DZ. Li et HQ. Yang and Cscandens Bor. Leptocanna Chia et HL. Fung and Cvirulentum YM Yang et F. Du are synonyms of Cephalostachyum Munro and Cfuchsianum Gamble et Hook. f. respectively. On the other hand, Cpergracile Munro and Cvirgatum (Munro) Kurz are morphologically closer to Schizostachyum Nees than to Cephalostachyum, and they should be treated as members of Schizostachyum. This paper is of significance to a worldwide revision of Cephalostachyum.  相似文献   

2.
The cytological studies were performed in 11 populations of Dicranostigma lactucoides, Dleptopodum, and Derectum and one population for Galucium fimbrilligerum. All three species of Dicranostigma possessed chromosome number 2n=2x=12, of which chromosome numbers for Derectum and Dlactucoides are reported here for the first time. Glaucium fimbrilligerum presented the number 2n=2x=10, which is not only new to the genus but also the known lowest number for Glaucium.  相似文献   

3.
Based on data collected from field surveys, biomass carbon accounting parameters including biomass conversion and expansion factor (BCEF), biomass expansion factor (BEF) and root shoot ratio (R) for Pinus kesiya var. langbianensis plantation were calculated, and relationships between the parameters and relative stand factors were studied. Main findings were as follows. (1) Mean BCEF for Pinus kesiya var. langbianensis plantation was 05483 Mg m 3(n=30, 95% confidence interval=05357-05609), lower than the IPCC default value. BCEF for Pinus kesiya var langbianensis plantation was negatively related to stand form height (FH), mean stand height (H), stand growing stock (V) and stand age(A) (P<005). BCEF was negatively related to mean diameter at breast height (D), but not statistically significant(P >005), positively related to stand density (N), not statistically significant(P>005). Regression equations developed for calculating BCEF with stand factors did not give satisfied estimates. (2) Mean BEF for Pinus kesiya var langbianensis plantation was 178378 (n=30, 95% confidence interval=171714-185043), higher than the IPCC default value. BEF was negatively related to D、H、FH、V and A (P <001), positively related to N (P <005). Regression equations of y=a+bx+cx2 performed well to calculating BEF with A and V as variables. Regression equation of y=a+b/x performed well to calculate BEF with N. Regression equations of y=a xb performed well to calculate BEF with FH、H and D as variables. (3) Mean R for Pinus kesiya varlangbianensis plantation was 02400 (n=30, 95% confidence interval=02194-02606), close to the IPCC default value. R was negatively related to D、H、FH、V and A (P <001), positively related to N (P <005). Regression equations of y= a+bx +cx2 performed well to calculate R with D、H、FH、V and Aas variables. Regression equation of y=a+b/x performed well to calculate R with N.  相似文献   

4.
利用微卫星标记研究鸭品种的遗传多样性   总被引:2,自引:0,他引:2  
利用32个微卫星标记研究了5个福建省地方鸭品种(金定鸭、连城白鸭、莆田黑鸭、山麻鸭和番鸭)和2个对照品种(北京鸭和卡基康贝尔鸭)的遗传多样性和种质特性.结果表明:32个微卫星标记在7个鸭品种中检测到371个等位基因,平均每个基因座有11.719个等位基因,平均多态信息含量为0.522,有效等位基因数在5.141~6961,基因杂合度变化范围在0.512~0.700,杂合度较高;基于Nei氏标准遗传距离(DS)和DA遗传距离,采用UPGMA方法构建了系统发生树,将金定鸭、莆田黑鸭、连城白鸭、山麻鸭和卡基康贝尔鸭聚为一类,而北京鸭和番鸭各自聚为一类.所得聚类图与种群的真实关系较为符合.  相似文献   

5.
为研究大鼠红细胞对葡萄糖利用的异头物选择性及其作用机制,应用大鼠红细胞,对葡萄糖的两种异头物作了异构化速率、乳酸生成量、内流速度和大鼠红细胞已糖激酶作用下的磷酸化速度等进行了测定.结果指出,37℃时大鼠红细胞的D-葡萄糖β-异头物和α-异头物代谢成乳酸的速度分别是0.27μmol/gHb(3min)和0.21μmol/gHb(3min),即前者快于后者30%.同时β-D-葡萄糖向红细胞内转运速度也快于后者:分别是5.0和3.5μmol/gHb(3min).大鼠红细胞已糖激酶的葡萄糖磷酸化速率实验结果指出:β-异头物比α-异头物快30%;对于该两种异头物已糖激酶的Km值均为53μmol/L.红细胞与α-和β-D-葡萄糖保温1min后,其葡萄糖浓度均达到1mmol/L左右,说明至少在1min内对于已糖激酶的磷酸化此两种异头物的葡萄糖浓度均已饱和.这些结果提示,大鼠红细胞葡萄糖利用的β-异头物优选性主要与其磷酸化速度有关,而与其转运速度关系不大.  相似文献   

6.
模拟土壤温度升高对湿草甸小叶章生长及生理特性的影响   总被引:3,自引:0,他引:3  
采用改进的电缆加热升温方法,研究了土壤温度升高1 ℃~3 ℃对湿草甸小叶章生长及生理特性的影响.结果表明:土壤温度升高明显促进了小叶章植株的生长淹水处理条件下各指标的增长程度依次为:根系总吸收面积(60%)>叶面积(37.32%)>分蘖数(25.81%)>根系体积(24.67%)>株高(18.2%);非淹水处理条件下为:根系总吸收面积(37.47%)>根系体积(36.26%)>叶面积(32.9%)>分蘖数(32.77%)>株高(12.09%).淹水处理条件下小叶章各生理指标对温度升高的响应较为显著,升温淹水处理下小叶章的总叶绿素含量、根部可溶性蛋白含量均呈增加趋势(9.8%和23.88%),而叶片可溶性蛋白和可溶性糖及根部可溶性糖含量显著下降(24.67%、22.92%和35.23%).说明土温升高1 ℃~3 ℃能够显著促进湿草甸小叶章的生长,且其生理特性对土温升高的响应程度因水分条件而异.  相似文献   

7.
8.
A species of the genus Delphinium (Ranunculaceae), Dbrachyurum, is described as new from Yunnan Province. The diagnostic differences between it and the other species, with which it belongs to the same subsection, are given.  相似文献   

9.
描述发现自云南的毛茛科翠雀属一新种,短尾翠雀花,并给出其与其隶属同一亚组的其他种的区别特征。  相似文献   

10.
A new species of Gesneriaceae from Honghe County, Southeastern Yunnan, China, Tremacron hongheense WH. Chen & YM. Shui, is described and illustrated. The new species is similar to Tremacron forrestii Craib, but differs by its leaf blade adaxially sparsely long setose (vs. densely white appressed pubescent and sparsely rusty brown villous), corolla tube outside short white glandular (vs. nearly glabrous), corolla lobes red and thickening at apex, especially adaxial lip (vs. yellow and not thickening), stamens 16-18cm long (vs. 04-12cm long), staminode 05-14cm long (vs. 02-04cm long).  相似文献   

11.
群体分布和灌溉对冬小麦农田光能利用的影响   总被引:14,自引:1,他引:14  
于2006-2008年进行冬小麦田间试验,设置行距×株距分别为:7 cm×7 cm(A)、14 cm×3.5 cm(B)、24.5cm×2 cm(C)、49 cm×1 cm(D)4种群体分布方式,每种分布方式设4种灌溉处理:整个生育期内不灌溉,灌拔节水,灌拔节和抽穗水,灌拔节、抽穗和灌浆水(每次灌水量相同,均为0.60 m3),研究在同一群体密度(2.04×106 株·hm-2)下不同群体分布和灌溉对冬小麦光能利用状况的影响及其在生产中的利用价值.结果表明:A、B处理的群体分蘖数和叶面积指数(LAI)显著高于C、D处理;随着行距的加大,光合有效辐射(PAR)透射率逐渐增多,而PAR截获率呈下降趋势;增加灌溉可提高冬小麦群体单茎数和LAI,降低PAR透射率,从而明显提高了PAR总截获率.冠层内PAR截获率表现为上强下弱的趋势,相对均匀的群体分布和所有灌溉处理均显著增加了冠层40 cm以上的PAR截获率.冬小麦光能利用率(RUE)随行距增大而逐渐降低,其中,A、B、C、D处理总RUE两年的均值分别为1.24%、1.27%、1.21%和1.06%,B处理较C、D处理分别提高了5.21%和19.56%,差异显著.群体分布相对均匀的A、B处理可显著改善冬小麦群体结构和PAR截获状况,有利于充分利用光能;所有灌溉处理也可影响群体结构,进而明显提高作物的RUE.  相似文献   

12.
A new oxyneolignan, claulignan (1), together with seven known compounds (2-8), were isolated from the methanol extract of the roots and stems of Clausena lansium. Their structures were elucidated on the basis of 1D and 2D NMR experiments and mass spectrometry. Compounds 2-8 were isolated from the genus Clausena for the first time. Compounds 1 and 6 showed cytotoxicity against human cervical cancer HeLa cell line with the IC50values of 2503 and 5399μM, respectively. Compound 3 exhibited antioxidant activity in the DPPH assay with the EC50 value of 26896g·kg-1.  相似文献   

13.
In this paper, we studied the response of photosynthesis and growth in Dendrobium officinale to temperature under the control experiment to provide a theoretical basis for its cultivation. Temperature had a significant effect on the photosynthetic rate (Pn) of Dofficinale. The light saturated photosynthesis at ambient CO2 concentration (Pmax) of the plants were highest at 30℃. High photosynthetic rate at 30℃ were related to the more balance between the maximum rate of electron transport and maximum rate of RuBP mediated carboxylation. Moreover temperature also showed a significant effect on the growth and polysaccharide content of D.officinale′s stem. The polysaccharide content of Dofficinale at 20℃ was significantly higher than that at other temperatures, while the stem length, stem node number, stem fresh weight and stem dry weight were achieved the highest point at 30℃. The results showed that, the temperature of 30℃ was more appropriate for the photosynthesis of Dofficinale, while the plants at 20℃ have higher polysaccharide content.  相似文献   

14.
虾池常见微藻种群温度、盐度和氮、磷含量生态位   总被引:3,自引:0,他引:3  
就温度、盐度、氮磷含量设计试验,对4种虾池常见微藻种群新月菱形藻、啮蚀隐藻、微绿球藻、蛋白核小球藻的生态位进行研究.结果显示:啮蚀隐藻在温度和盐度资源上的生态位宽度值最大,分别达0.980和0.988,新月菱形藻在氮、磷含量资源上的生态位宽度值最大,达0.990,蛋白核小球藻在各资源的生态位宽度值均最小,平均只有0.926;啮蚀隐藻与蛋白核小球藻在温度和盐度资源上的生态位重叠值最小,分别为0.809和0.702,啮蚀隐藻与新月菱形藻在氮、磷含量资源上的生态位重叠值最小,只有0.829,蛋白核小球藻与微绿球藻在温度、盐度和氮、磷含量资源上的生态位重叠值均最大,分别为0.986、0.974和0.989.表明在养殖水环境调控过程中,啮蚀隐藻适宜与新月菱形藻、微绿球藻或蛋白核小球藻共同培育,而蛋白核小球藻和微绿球藻对资源的竞争性明显,不适合同时引入同一池塘进行培育.  相似文献   

15.
采用砂培方法在温室条件下研究了低分子量有机酸柠檬酸、草酸、苹果酸及3种酸的混合物对大豆植株氮素积累、结瘤和固氮的影响.结果表明:低分子量有机酸对大豆植株氮素积累有显著的抑制作用,使大豆地上部各时期氮素积累量的降低幅度分别为:苗期17.6%~44.9%,花期29.8%~88.4%,鼓粒期9.18%~69.6%,成熟期2.21%~41.7%;低分子量有机酸对大豆根瘤生长和固氮能力也有显著影响,表现为使根瘤数量、根瘤固氮酶活性和豆血红蛋白含量显著降低,降低幅度分别为11.4%~59.6%,80.5%~91.7%和11.9%~59.9%,从而使大豆的固氮效率降低,最终导致大豆的固氮量较对照显著降低(降低幅度9.71%~64.5%).低分子量有机酸对大豆氮积累、根瘤生长和固氮能力的抑制作用随浓度的增加而增加.3种有机酸中,草酸的抑制作用相对大于柠檬酸和苹果酸,3种有机酸混合后,抑制作用加强.  相似文献   

16.
湖南茶叶植物资源的评价   总被引:3,自引:0,他引:3  
对城步峒茶、江华苦茶、汝城白毛茶和云台山种等湖南茶叶植物资源的主要化学成分、光合特性和生产性状进行了研究。结果表明,茶多酚与儿茶素含量从高到低依次为汝城白毛茶、江华苦茶、城步峒茶、云台山种;各资源的游离氨基酸、茶氨酸和咖啡碱含量均为正常水平;汝城白毛茶属高茶多酚资源,它所含生物碱的组成方式与毛叶茶龙门模式种不同,虽可可碱和茶叶碱含量比茶种高,但仍以咖啡碱为主。在阴天阴凉条件下的净光合速率为汝城白毛茶>城步峒茶>江华苦茶>云台山种,净光合速率与光量子通量、叶面温度呈极显著正相关,与气孔阻力呈极显著负相关,相关系数分别为09278、09115和-08937。在晴天高温度强光条件下,净光合速率为云台山种>城步峒茶>江华苦茶>汝城白毛花,净光合速率与光量子通量、叶面温度和气孔阻力都呈极显著负相关,相关系数分别为-09165、-09328、-09031。在主要生产性状中,汝城白毛茶能安全通过-6℃的低温,在高茶多酚资源中,抗寒性突出,是选育红茶良种的一个非常有益的关键性状。  相似文献   

17.
Raphiocarpus jinpingensis WH. Chen & YM. Shui, a new species of Gesneriaceae, is described and illustrated, from the Xilong Mountain of Jinping County in Yunnan, China, bordering to North Vietnam. The new species is similar as Rpetelotii (Pellegr.) Burtt in shapes of corolla and yellowish flowers, and differs from Rpetelotii mainly in its plants with dense pubescence and calyx tubes subequal to calyx lobes.Its pollen grains and seeds are reported here under Scanning Electonic Microscope (SEM).  相似文献   

18.
研究了内生多粘类芽孢杆菌(Paenibacillus polymyxa)S-7对甜菜叶片光合参数和产量的影响.结果表明:接种内生多粘类芽孢杆菌S-7能显著促进甜菜光合作用,其中叶片净光合速率(Pn)、气孔限制值(Ls)、气孔导度(Gs)和蒸腾速率(Tr )的平均值分别提高了16.11%、23.82%、41.91%和34.80%;叶片胞间CO2浓度(Ci)平均值降低了21.09%.生物学产量和含糖率分别提高了25.63%和17.46%,促进了甜菜产量和品质提高.表明内生菌不仅影响甜菜光合参数,而且对甜菜产量和品质的提高具有明显的促进作用.  相似文献   

19.
We focused on the systematic positions and relationships of three sections of Camellia subgenThea of Theaceae, i.e., sect.Longipedicellata, sect.Chrysantha (golden camellias) and sect.Longissima by using four chloroplast DNA regions (rpl16, psbA trnH, trnL F & rpl32 trnL). We sampled 28 species representing four subgenus, 11 sections in Camellia and two outgroups. Combined analyses of chloroplast DNA sequence data sets are performed with the neighbor joining, maximum parsimony and Bayesian inference methods, and the gene trees are constructed. The topologies of gene trees revealed that: 1) sect. Chrysantha is paraphyletic or polyphyletic, containing three parallel lineages and Camellia longipedicellata (type of sectLongipedicellata) nested inside; 2) all four species from Vietnam, together with C. longipedicellata, forming a well supported monophyletic clade, which implies the close relationship between sect. Longipedicellata and sect.Chrysantha; and 3) sectLongissima is not monophyletic because C.hekouensis is the sister to the rest of Camellia species. The systematic position of C.longissima and the relationship between sect.Longissima and sect.Longipedicellata are unsolved.  相似文献   

20.
The vascular flora of the Siahrud e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28289 hectares. A total of 711 plant specimens were collected and 616 species, subspecies, and varieties, belonging to 373 genera and 101 families were identified. Of these, 14 species (23%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species, including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows: Euro Siberian 212%, Iran Turanian & Euro Siberian 168%, Pluriregional 117%, Iran Turanian 106%, and Cosmopolite 55%.  相似文献   

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