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71.
JARLE W. BJERKE HARRIE J. M. SIPMAN 《Botanical journal of the Linnean Society. Linnean Society of London》2007,153(4):489-499
The genus Menegazzia (Parmeliaceae, lichenized ascomycetes) in Malaysia and Indonesia is studied. Some specimens from Papua New Guinea are also included. The great majority of available specimens are from Kinabalu Park, State of Sabah, Malaysia. Three species are described as new to science, namely the two sorediate species M. capitata (from Sabah and Pahang in Malaysia) and M. sabahensis (from Sabah), and the fertile, primary species M. monospora (from Sabah and Papua New Guinea). M. asahinae , M. dissoluta , and M. efflorescens are reported for the first time from Malaysia, and M. subsimilis is reported for the first time from Malaysia and Indonesia. The subgenus Megamenegazzia is newly described to accommodate the large, broad-lobed species with numerous perforations on the lower surface. M. efflorescens is selected as the type species for the new subgenus. Notes are also provided on the type specimens of Hypogymnia pectinatula , a species originally considered as belonging to Menegazzia . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 489–499. 相似文献
72.
L.W.D. van Raamsdonk M. Vrielink-van Ginkel C. Kik 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(7):1000-1009
Amplified fragment length polymorphisms (AFLPs) for assessing nuclear DNA diversity have been used for the reconstruction
of the phylogeny and evolution of several sections of Allium subgenus Rhizirideum. A dataset of 355 characters for 33 accessions belonging to 20 species has been compiled. The band-sharing of five interspecific
hybrids and of an F2 population between Allium cepa and Allium roylei with their parents indicated a heterozygosity level between 6 and 14%, which allows the use of dominant markers such as AFLPs
for phylogeny reconstruction. A majority rule consensus tree based on 56 most-parsimonius trees (CI = 0.528) revealed a separate
clade for each of the sections, Cepa, Rhizirideum and Schoenoprasum, and one clade combining the sections Oreiprason and Petroprason. An unweighted pair group mean average (UPGMA)-based dendrogram showed the same subdivision. The trees and the ’Hybrid Distance’
approach both supported the assumption of a hybrid origin for A. roylei with considerable subsequent secondary evolution. The establishment of three alliances in the section Cepa and the close relationship of sections Oreiprason and Petroprason are now confirmed. The predictions of the Soybean domestication scenario, i.e. selection of a crop from one progenitor with
subsequent narrowing of the genetic diversity of the crop, which applies to the cultigens A. cepa and Allium fistulosum, is supported by the Hybrid Distance approach.
Received: 23 August 1999 / Accepted: 14 September 1999 相似文献
73.
为评价星花玉兰及其实生选育品种‘菊花’以及其与柳叶玉兰的杂交品种‘皮鲁埃特’的耐涝性强弱,并为后续星花玉兰耐涝品种选育提供理论依据。通过14 d的水涝胁迫,研究3种玉兰叶片生理、内源激素和光合特性等相关的14个指标变化。利用主成分分析法,比较超氧化物歧化酶(SOD)、丙二醛(MDA)、可溶性蛋白、脱落酸(ABA)和1-氨基环丙烷-1-羧酸(ACC)这5个作为评价耐涝性指标的重要性以及评价耐涝性,同时利用隶属函数分析法对5个指标进行耐涝性评价。结果表明:(1)3种玉兰在水涝胁迫后叶片的净光合速率(P n)、气孔导度(G_(s))、蒸腾速率(T_(r))、叶绿素含量、初始荧光(F_(o))、最大荧光(F_(m))、PSⅡ最大光化学量子产量(F_(v)/F_(m))、PSⅡ有效光化学量子产量(Yield)和可溶性蛋白含量均显著降低,MDA、ABA含量和SOD活性均有不同的增加幅度。‘菊花’和星花玉兰处理组的C_(i)、ACC显著增加,而‘皮鲁埃特’的显著降低。(2)评价3种玉兰耐涝性的生理及内源激素指标重要性依次为ACC、SOD、ABA、可溶性蛋白和MDA。(3)通过主成分分析法和隶属函数分析法对3种玉兰进行综合评价,耐涝性强弱依次为‘皮鲁埃特’、星花玉兰和‘菊花’。 相似文献
74.
本文通过对中国伪卷绵蚜属的研究,发现1新亚属,即卵伪卷绵亚属Oothecabius;7新种,即北京伪卷绵蚜Thecabius(Thecabius)bei jingensis Zhang, sp. nov. ;吸杨伪卷绵蚜T. (T. )populisuctus Zhang, sp. nov. ;短毛伪卷绵蚜T.(Oothecabius)brach ychaetus Zhang, sp. nov. ;南京伪卷绵蚜T. (O. )nan jingensis Zhang, sp. nov, ;次生伪卷绵蚜T. (O. )sequelus Zhang, sp. nov. ;峨眉伪卷绵蚜T. (Parathecabius)emeianus Zhang, Sp. nov. ;钟伪卷绵蚜T. (P. )Zhongi Zhang, sp. nov. 。1新亚种,即东方伪卷绵蚜岷亚种T. (T. )orientalis minensis Zhang, ssp. nov. 。对该属与近缘属之间的系统演化关系进行了研究,并且给出亚属及种的检索表。模式标本存放在中国科学院动物研究所标本馆。 相似文献
75.
76.
Peng-Cheng An De-Liang Tang Hui Chen Qian Yang Su-Ting Ding 《Historical Biology》2013,25(10):1412-1422
AbstractThe fossil records of Pinus L. are abundant since the Late Cretaceous, especially for the subgenus Pinus L. (the hard pines). However, those of the subgenus Strobus (D. Don) Lemmon (the white or soft pines) are not well documented. In this study, we describe a new species of white pines, Pinus plioarmandii sp. nov., from the Pliocene of western Yunnan, southwestern China. This species mostly resembles extant P. armandii Franch. in gross morphology and cuticular structure of needles. Molecular dating showed that the Asian white pines split into two lineages around the Late Miocene, and the Pinus armandii clade diverged at the Early Pliocene. The present fossil occurrence indicates that Pinus armandii might originate in southwest China and probably in the western Yunnan. The glacial events during the Pleistocene might be the major factors for the retreat of the white pines from western Yunnan, and the rapid uplift of the Yunnan Plateau and deep incision of the river valleys since the Pliocene had posed a significant geographic barrier for their reconnection in the subsequent warm climate condition. 相似文献
77.
Guangxue Zhang 《Insect Science》1995,2(4):291-299
Abstract Subgenus Selibaizongia Zhang Subg. nov., Baizongia (S.) ovagalla sp. nov. and Baizongia (S.) sensucopia sp. nov. are new to science. It is suggested that Baizongia aedificator (Buckton, 1893) should be resurrected as valid name. 相似文献
78.
中国库蠓属吉林亚属已知有 2种。在广西发现的库蠓属吉林亚属一新种 :Culicoides (Jilinocoides)guanxien sissp .nov . ,正模♀ ,1974 0 8 2 9,广西壮族自治区凭祥市 ,郝宝善采。本新种与犍为库蠓CulicoidesqianweiensisYu 1982相近似 ,但后者触角第 7、9节有嗅觉器 ,触须第 3节无感觉器窝 ,大颚齿 14枚 ,翅基淡斑和径中淡斑的形状与本新种明显不同。模式标本保存在沈阳军区军事医学研究所 ,沈阳 110 0 34。 相似文献
79.
Culture experiments on Ectocarpus fasciculatus Harv. have been carried out using material from three separate localities. Under certain conditions, which have yet to be exactly defined, sporelings develop into plants quite unlike ‘normal’ Ectocarpus but resembling Myrionema corunnae Sauv. Reference is made to a field observation of a similar phenomenon by Jaasund (1965) and the status of M. corunnae is discussed. 相似文献
80.
报道中国四川和宁夏巨须隐翅虫属Oxyporus Fablicius,巨须隐翅虫亚属subgenus Oxyporus12个种.记述了 4新种,黄缘巨须隐翅虫Oxyporus aureomarginatus,北川巨须隐翅虫O.beichuanus,海螺沟巨须隐翅虫O.hailuogou和肩斑巨须隐翅虫O.humerosus.简述了1新亚种,扬氏高山巨须隐翅虫O.altus yangae的特征.首次记述了黑胸巨须隐翅虫O.nigricollis Zheng的雄性.提供了高山巨须隐翅虫Oxyporus altus Huang,Zhao et Li,仙台巨须隐翅虫O.germanus Sharp,黑腹蕈巨须隐翅虫O.humerocroceus Huang,Zhao et Li,溪巨须隐翅虫O.riparius Zheng,橘红巨须隐翅虫O.rufus(Linné),中华巨须隐翅虫O.sinicus Huang,Zhao et Li,和横沟巨须隐翅虫O.transversesrlcatus Bernhauer的新分布.所有研究标本都附有彩色整体外形图,新种和新的雄性配有特征图. 相似文献