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1. chinaXiv:202004.00001 [pdf]

Reappraisal of Serridentinus gobiensis Osborn & Granger and Miomastodon tongxinensis Chen:the validity of Miomastodon

WANG Shi-Qi; ZHANG Xiao-Xiao; LI Chun-Xiao 
Subjects: Biology >> Zoology

The elephantimorph proboscideans, Serridentinus gobiensis Osborn & Granger, 1932, and Miomastodon tongxinensis Chen, 1978, from the Middle Miocene of northern China, were revised as Zygolophodon gobiensis (Osborn & Granger, 1932). However, their phylogenetic positions are still being debated because of their intermediate morphology between the typical bunodont (Gomphotheriidae) and zygodont (Mammutidae) elephantimorphs. In the present paper, we compare their dental and mandibular morphology with that of the Eurasian Z. turicensis, Gomphotherium subtapiroideum, and G. tassyi, as well as the North American Mio. merriami and G. productum. It appears that S. gobiensis and Mio. tongxinensis share with Mio. merriami the slightly more bunodont molar morphology than that of Z. turicensis, e.g., the thicker enamel, thicker pretrite crescentoids, higher interlophid enamel pillars in buccal view, and the narrower contour majorly caused by the narrower posttrite half loph(id)s. S. gobiensis and Mio. merriami also possess an “erected oval cross-sectioned mandibular tusk”, in which the cross-section is mediolaterally compressed (dorsoventral diameter being larger than the mediolateral one). Whereas, in Z. turicensis and G. productum, the mandibular tusk is “laid oval cross-sectioned”, in which the cross-section is dorsoventrally compressed (dorsoventral diameter is smaller than the mediolateral one). Therefore, it is reasonable to revive the genus Miomastodon Osborn, 1922, which contains the species that were previously attributed to Zygolophodon, but they have relatively bunodont molar morphology (i.e., the robust type of the Z. turicensis group). The mandibular tusk with erected oval cross-section seems to be a synapomorphy of Miomastodon species. Furthermore, the molar morphology of G. subtapiroideum and G. tassyi also exhibits intermediate status between the typical bunodonts and zygodonts. However, the mandibular symphysis of G. subtapiroideum and G. tassyi is stronger than that of Miomastodon, and the mandibular tusk is pyriform cross-sectioned. The validity of Miomastodon and G. subtapiroideum/tassyi obscures the boundary between the Gomphotheriidae and Mammutidae, and suggests that the evolutions of the Gomphotheriidae and Mammutidae are deeply involved in with each other, rather than straightforwardly detached. This phenomenon has been revealed by a collagen sequence analysis among Notiomastodon, Mammut, and extant elephants, which should be further studied.

submitted time 2020-03-31 From cooperative journals:《古脊椎动物学报》 Hits161Downloads65 Comment 0

2. chinaXiv:202004.00002 [pdf]

New material of Cervidae (Artiodactyla, Mammalia) from Xinyaozi Ravine in Shanxi, North China

DONG Wei; BAI Wei-Peng; PAN Yue; LIU Wen-Hui
Subjects: Biology >> Zoology

Many cervid specimens were uncovered during the field exploration for Nihewan beds at the beginning of the 1980s from Taijiaping, Shuichongkou and Dazhuangke localities along Xinyaozi Ravine at Nangaoya Township of Tianzhen County, Shanxi Province in North China. Recent studies on the cervid material identified seven species of Cervidae in total: Muntiacus bohlini, Cervavitus cf. C. huadeensis, Axis shansius, Nipponicervus elegans, Elaphurus davidianus predavidianus, E. bifurcatus from the Early Pleistocene deposits at Taijiaping and Shuichongkou localities, and Cervus (Elaphus) elaphus from uncertain horizon at Dazhuangke. At least the previous six species of cervids were from Nihewan Formation (Nihewanian or equivalent to European middle and late Villafranchian), i.e. the Early Pleistocene, in Sangganhe Basin area.Cervavitus cf. C. huadeensis and A. shansius were survivors from the Late Neogene; M. bohlini,N. elegans, E. davidianus predavidianus and E. bifurcatus are new forms of the Early Pleistocene.If Dazhuangke horizon can be dated as those of Shuichongkou and Taijiaping localities, the appearance of elaphoid cervids could be traced back to the Early Pleistocene, and the evolution of elaphoid antler would start from absence to presence of bez tine. The presence of Elaphurus and Nipponicervus in mainland China and Japanese archipelago implies further that the sea level was dropped down that these cervids could migrate from the mainland to the islands. The abundance of folivorous cervid specimens in the Xinyaozi Ravine area indicates the existence of a certain scale of forested environment in Sangganhe Basin area during the Early Pleistocene.

submitted time 2020-03-31 From cooperative journals:《古脊椎动物学报》 Hits131Downloads62 Comment 0

3. chinaXiv:202004.00003 [pdf]

A new species of Amynodontopsis (Perissodactyla: Amynodontidae) from the Middle Eocene of Jiyuan, Henan, China

WANG Xiao-Yang; WANG Yuan-Qing; ZHANG Rui; ZHANG Zhong-Hui;  LIU Xiao-Ling; REN Li-Ping
Subjects: Biology >> Zoology

An adult amynodont skull, collected from the Middle Eocene Niezhuang Formation of Jiyuan Basin (Henan, China), is recognized as a new species Amynodontopsis jiyuanensis sp. nov. The specimen possesses the typical features of the genus Amynodontopsis, such as a dolichocephalic skull with elevated roof, premaxilla-nasal contact, large preorbital fossa extending posteriorly medial to the orbit, inner surface of anterior orbital bar concave in continuation with the preorbital fossa, antecrochet usually presented on M1, and metastyle of M3 strongly deflected labially. A. jiyuanensis is diagnosed by a combination of the following characters: long nasals, nasal process of premaxilla extending far back laterally below the nasal and excluding the maxilla from the border of external nares, nasal notch above the post-canine diastema, more transverse and proportionally longer protoloph and metaloph on upper molars. Comparison with known species of Amynodontopsis indicates that it is the most primitive one in the genus, due to the possession of primitive characters. Associated fossil mammals support a correlation of the strata bearing A. jiyuanensis with the Shara Murun Formation of the Erlian Basin, Nei Mongol, China, namely the Middle Eocene Sharamurunian Asian Land Mammal Age (ALMA), prior to all other known Amynodontopsis species. The earlier geologic age and primitive morphological features of A. jiyuanensis suggest that Amynodontopsis has an Asian origin in the Middle Eocene and later immigrated into North America.

submitted time 2020-03-31 From cooperative journals:《古脊椎动物学报》 Hits119Downloads46 Comment 0

4. chinaXiv:202004.00004 [pdf]

A Late Miocene Huerzelerimys (Rodentia: Muridae) skull from Hezheng, Gansu, China

WANG Ban-Yue; QIU Zhan-Xiang;  LI Lü-Zhou
Subjects: Biology >> Zoology

A skull with mandible and several cervicals of a new species of Huerzelerimys, H.asiaticus, collected from the Late Miocene Liushu Formation in Linxia Basin, Gansu Province,is described in this paper. The skull is the first one ever found for the genus Huerzelerimys. Its main characters are: size small; skull broad and short with stout rostrum; interorbital roof narrow;premaxillary laterodorsal crest well developed; frontal crests weak and subparallel; incisive foramina long, with their posterior ends lined up with anterior root of M1; posterior palatal foramina located mesial to M2; caudal border of hard palate lying posterior to M3;interpterygoid foramen absent; alisphenoid canal bony; bulla large and inflated; internal carotid foramen located near the basilar tubercle; mandible having low horizontal ramus and deeply concave diastema; anterior end of masseteric ridge lined up with anterior margin of m1; mental foramen situated slightly anterior to masseteric ridge and anteroventral to m1, near to mandibular diastema; upper incisors orthodont; M1 having slightly anteriorly located t1; in M1 and M2 t6 and t9 connected by distinct crest and t12 crest-like; t1 and t3 of M2 and t1 of M3 connected to t5; M3 having t3 and a large isolated t8; small Acc of m1 connected with both Alc and Abc; m1 and m2 having distinct buccal cingula, larger c2 attached to protoconid, and low crest-like posterior heel; m2 and m3 having isolated Abc; c1 absent in m3. The evolutionary level of the described skull tends to show that the age of the upper part of the Liushu Formation yielding H. asiaticus may belong to late Bahean, corresponding to European upper MN11 or lower MN12.

submitted time 2020-03-31 From cooperative journals:《古脊椎动物学报》 Hits120Downloads55 Comment 0

5. chinaXiv:202003.00058 [pdf]

广藿香FPPS基因原核表达及茉莉酸甲酯对FPPS表达量的影响

卢昌华; 邓文静; 曾建荣; 刘键锺; 张宏意; 何梦玲; 严寒静
Subjects: Biology >> Botany >> Applied botany

法尼基焦磷酸合酶(farnesyl diphosphate synthase, FPPS)是广藿香甲羟戊酸途径中萜类物质生物合成的关键酶,其催化异戊二烯焦磷酸( IPP) 和二甲基烯丙基焦磷酸(DMAPP)合成萜类物质前体法尼基焦磷酸。为了进一步研究广藿香萜类合成途径的分子机制,本研究通过逆转录聚合酶链式反应获得PTS基因的cDNA序列,利用生物信息学软件预测FPPS编码蛋白的理化性质、结构和功能。结果表明该序列的开放阅读框全长1 050 bp,编码349个氨基酸,预测分子量为40 KD,等电点为5.43,存在一个结构域,参与异戊二烯化合物的合成,不存在信号肽,亚细胞定位于细胞质;系统发育分析表明广藿香FPPS氨基酸序列和丹参(Salvia miltiorrhiza Bunge)、撒尔维亚(Salvia officinalis Linn)的氨基酸序列亲缘关系最近。其次,为研究其蛋白的表达情况,该文使用无缝克隆技术构建pET-32b-FPPS原核表达载体,并导入菌株BL21(DE3)中,考察不同浓度异丙基-β-D-硫代半乳糖苷(IPTG)对诱导融合蛋白的表达量的影响。结果发现融合表达蛋白以包涵体形式存在沉淀中,4个浓度的IPTG诱导蛋白表达效果差异不明显。最后,为研究茉莉酸甲酯(MeJA)对FPPS表达量的影响,该文采用荧光定量技术分析0.1、0.25 mmol·L-1 MeJA对FPPS基因表达水平的影响,发现0.1 mmol·L-1 MeJA诱导后FPPS基因的表达量的趋势是先升高后降低再升高再降低;0.25 mmol·L-1 MeJA诱导后FPPS基因的表达量的趋势是先降低后升高再降低。推测植物体内MeJA浓度的变化能影响FPPS基因的表达,高浓度具抑制作用,低浓度具促进作用。本研究为广藿香萜类合成途径的研究奠定基础,为后续基因功能验证提供理论参考。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits312Downloads126 Comment 0

6. chinaXiv:202003.00059 [pdf]

杭白芷根中分泌道发生方式、分布及其挥发油积累过程研究

李博园;  王娟;  高静;  陈旋勐;  陈莹
Subjects: Biology >> Botany >> Applied botany

为探明杭白芷(Angelica dahurica var. formosana)根中分泌道发生方式、分布及其挥发油转运积累特征,利用光镜及透射电子显微镜技术观察了分泌道发生过程及挥发油转运特征,结合组织化学定位确定挥发油的主要积累部位。结果表明:杭白芷根中分泌道由中柱鞘细胞最先发生,次生结构中分泌道主要分布在韧皮部和皮层中。挥发油的合成不仅与分泌细胞中质体及细胞质有关,还与周围细胞关系密切。分泌细胞内高尔基体和内质网丰富,可能通过形成小泡参与转运,再经由细胞壁向腔道内转移。相邻分泌细胞靠近角隅处的细胞壁分泌活动活跃,腔道内积累大量电子致密物质。成熟分泌道中分泌细胞及其腔道内积累大量油滴,因此挥发油主要积累场所为分泌细胞及其腔道。本研究明确了杭白芷根中分泌道的发生方式、分布及其挥发油积累部位,揭示了分泌道发育过程中挥发油的转运积累特征,为进一步阐明分泌组织生长发育与有效成分积累关系研究提供详细理论依据。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits243Downloads107 Comment 0

7. chinaXiv:202003.00060 [pdf]

异叶泽兰的遗传多样性和居群历史动态研究

潘跃芝;  赵玉娟; 龚洵
Subjects: Biology >> Botany >> Applied botany

异叶泽兰属于菊科泽兰属,是该属分布海拔相对较高的植物,分布在青藏高原东部和横断山海拔1 700~3 000 m左右的地区。本研究利用ycf6-psbM和rpl32-trnL两个叶绿体DNA(cpDNA)片段以及核DNA片段ITS(nITS)作为分子标记,研究了异叶泽兰的遗传多样性及其分布特征,同时探讨了其居群历史动态。叶绿体片段联合分析结果显示单倍型多态性指数Hd为0.656,核苷酸多态性(π)为0.001 61;而ITS的平基因型多态性指数Hd为0.687,核苷酸多态性为0.002 35。因此异叶泽兰在物种水平遗传多样性水平不高。cpDNA和nITS分析结果都显示异叶泽兰居群水平总的遗传多样性大于居群内平均遗传多样性,遗传变异主要发生在居群间,居群间存在明显的遗传分化(cpDNA:Gst= 0.679,Nst= 0.655,FST = 0.655;nITS:Gst = 0.543,Nst = 0.370,FST = 0.584)。但是,由于Nst值小于Gst值,异叶泽兰的分布不具有明显的谱系地理结构。基于单倍型地理分布以及Network分析推测横断山区南部(川西南-滇西北)和云南中部可能是异叶泽兰在第四纪冰期时的两个避难所,中性检验和失配分析的结果支持异叶泽兰在冰期后未发生过居群扩张。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits225Downloads103 Comment 0

8. chinaXiv:202003.00061 [pdf]

大花铁线莲开花物候与传粉昆虫的研究

温馨; 张永胜;  尚禹含;  李海微;  冀李琼;  韩金秀;  王非
Subjects: Biology >> Botany >> Applied botany

大花铁线莲是我国东北地区兼具优良观赏性状及药用价值的野生植物资源。为了研究野生大花铁线莲在引种地的开花进程和传粉规律,探讨引种环境对其开花特性的影响,于2017年和2018年间对大花铁线莲在个体、群体水平的开花物候和传粉特性进行了连续两年的观测和统计。结果表明:(1)大花铁线莲的群体花期在5月中旬至6月中下旬,两年个体开花进程基本相似,均呈单峰曲线;群体始花期和末花期时间较短,而盛花期时间较长,约为20 d左右,单株花期为5~7 d,种群花期长达30 d以上。群体开花比例呈现先升后降的变化趋势,累计开花比例在开花后一周左右达到100%。 两年的开花同步指数(Si)分别为 0.76和0.74,说明大花铁线莲两年间的开花特性差异较小。(2)大花铁线莲访花昆虫主要有6目13科18种,它们在访花频率、访花行为以及在单花停留时间上都有一定的差异。传粉昆虫主要是8种,分属于3目4科。中华蜜蜂、食蚜蝇和短尾管食蚜蝇访花频率高,在单花上停留时间较长,可以初步认定它们在对大花铁线莲的花粉传播中有重要作用。通过对大花铁线莲开花特性和访花昆虫的观查以及盗蜜昆虫行为的研究,为大花铁线莲的迁地保护和引种栽培提供科学依据。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits213Downloads99 Comment 0

9. chinaXiv:202003.00062 [pdf]

Na2SO4和Na2CO3胁迫下苦楝幼苗的形态及光合生理特性

张远兰;  胡鑫;  蔡金峰;  国靖;  郁万文; 曹福亮;  汪贵斌
Subjects: Biology >> Botany >> Applied botany

为探索苦楝应对盐胁迫的响应机制和为苦楝在盐碱地区的推广应用提供理论参考。该研究以一年生苦楝(Melia azedarach)实生苗为材料,在盆栽条件下设置中性盐Na2SO4和碱性盐Na2CO3 3个盐浓度(200、400和600 mmol·L-1)处理40 d,研究苦楝的抗盐碱水平及在不同程度盐碱胁迫条件下的生长及光合生理变化。结果表明,随着盐浓度的提高,苦楝的苗高、地径和生物量的增长量均呈现下降趋势,且碱性盐胁迫条件下降程度更大,盐胁迫提高苦楝的根冠比。处理10 d时,苦楝幼苗的所有光合指标随中性盐和碱性盐浓度的提高呈相似的下降特征,碱性盐胁迫条件下的降低幅度显著大于中性盐胁迫,且随处理时间的增加,中性盐和碱性盐处理下苦楝幼苗的净光合速率和蒸腾速率显著降低。随着盐浓度的提高,苦楝的叶绿素含量呈现下降趋势,200 mmol·L-1盐胁迫对叶绿素含量影响较小,400和600 mmol·L-1盐碱胁迫均对叶绿素含量有显著影响。600 mmol·L-1碱性盐胁迫条件下,苦楝叶片相对电导率和饱和水分亏缺最高,显著高于其余处理。同等浓度下,碱性盐胁迫的苦楝叶片相对电导率和饱和水分亏缺显著高于中性盐胁迫处理。由此可见,苦楝具有一定的耐盐碱能力,碱性盐比中性盐对苦楝幼苗的影响更大。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits183Downloads94 Comment 0

10. chinaXiv:202003.00063 [pdf]

烟草TIR-NBS基因家族的生物信息学分析

董亚萍; 杨仕梅; 赵德刚; 宋 莉
Subjects: Biology >> Botany >> Applied botany

TIR-NBS基因是一类与植物抗病调节和生长发育密切相关的基因,其特征解析有助于对植物免疫和发育调节的认识。通过生物信息学分析方法,从基因鉴定、染色体分布、基因结构、蛋白性质和结构、信号肽、亚细胞定位和顺式作用元件等方面,对烟草TIR-NBS基因家族进行鉴定和分子特性分析。研究发现,烟草TIR-NBS基因家族含有30条成员,分布在21条染色体上,含有3~8个保守基序;编码蛋白均为不稳定蛋白,无信号肽,主要分布于细胞核、细胞质和叶绿体中,二级结构以α-螺旋和无规则卷曲为主要构成元件;进化时主要受纯化选择作用,与番茄的TIR-NBS基因亲缘关系最近;顺式作用元件分析表明其可能受光照、温度以及生长素、茉莉酸甲酯、脱落酸、水杨酸、赤霉素等激素调控。研究结果为进一步探究TIR-NBS基因的生物学功能及提高植物产量和品质提供了依据。

submitted time 2020-03-24 From cooperative journals:《广西植物》 Hits183Downloads95 Comment 0

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