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Search Results: 1 - 10 of 117992 matches for " YANG Da-Rong "
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The status of species diversity and conservation strategy of bumble bees, a pollination insect in Lancang River Basin of Yunnan, China
云南澜沧江流域传粉昆虫--熊蜂多样性现状与保护对策

YANG Da-Rong,
杨大荣

生物多样性 , 1999,
Abstract: 本文对澜沧江流域内热带地区的勐腊县、亚热带地区的南涧县和寒温带地区的德钦县3个低、中、高海拔地带的重要传粉昆虫——熊蜂属(Bombus)的多样性现状进行了观察研究,并与20年前的资料进行了比较分析。结果得出:20多年以来,由于植被人为的破坏严重,传粉昆虫的自然生存环境发生了较大的改变,致使3个不同地带的传粉昆虫一部分物种消失,一部分物种的群体减少,而少数原来极少采到或者未采到的物种和种群则成为优势群体。从而得出:在云南省澜沧江流域人为的生境改变,对传粉昆虫的物种多样性影响极大,要保护或者恢复传粉昆虫的种群,首要任务是保护和恢复生态系统。
The complete mitochondrial genomes of two ghost moths, Thitarodes renzhiensis and Thitarodes yunnanensis: the ancestral gene arrangement in Lepidoptera
Yong-Qiang Cao, Chuan Ma, Ji-Yue Chen, Da-Rong Yang
BMC Genomics , 2012, DOI: 10.1186/1471-2164-13-276
Abstract: The mitogenomes of Thitarodes renzhiensis and T. yunnanensis are 16,173?bp and 15,816?bp long with an A?+?T content of 81.28?% and 82.34?%, respectively. Both mitogenomes include 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and the A?+?T-rich region. Different tandem repeats in the A?+?T-rich region mainly account for the size difference between the two mitogenomes. All the protein-coding genes start with typical mitochondrial initiation codons, except for cox1 (CGA) and nad1 (TTG) in both mitogenomes. The anticodon of trnS(AGN) in T. renzhiensis and T. yunnanensis is UCU instead of the mostly used GCU in other sequenced Lepidoptera mitogenomes. The 1,584-bp sequence from rrnS to nad2 was also determined for an unspecified ghost moth (Thitarodes sp.), which has no repetitive sequence in the A?+?T-rich region. All three Thitarodes species possess the ancestral gene order with trnI-trnQ-trnM located between the A?+?T-rich region and nad2, which is different from the gene order trnM-trnI-trnQ in all previously sequenced Lepidoptera species. The formerly identified conserved elements of Lepidoptera mitogenomes (i.e. the motif ‘ATAGA’ and poly-T stretch in the A?+?T-rich region and the long intergenic spacer upstream of nad2) are absent in the Thitarodes mitogenomes.The mitogenomes of T. renzhiensis and T. yunnanensis exhibit unusual features compared with the previously determined Lepidoptera mitogenomes. Their ancestral gene order indicates that the tRNA rearrangement event(s) likely occurred after Hepialoidea diverged from other lepidopteran lineages. Characterization of the two ghost moth mitogenomes has enriched our knowledge of Lepidoptera mitogenomes and contributed to our understanding of the mechanisms underlying mitogenome evolution, especially gene rearrangements.
Oviposition timing and community structure of Ficus curtipes fig wasps
钝叶榕榕果内榕小蜂的产卵顺序及其群落结构

ZHANG Feng-ping,YANG Da-rong,
张凤萍
,杨大荣

应用生态学报 , 2009,
Abstract: 通过对钝叶榕榕小蜂行为的观察以及榕果内各类小花的统计,研究了钝叶榕12种榕小蜂的产卵行为和群落结构.结果表明:钝叶榕中除了传粉榕小蜂Eupristina sp.进入果腔产卵以外,还有2种非传粉榕小蜂(杨氏榕树金小蜂和Lipothymus sp.)与传粉榕小蜂在同一时期进入果腔产卵,其他9种非传粉榕小蜂(Walkerella sp.、Micranisa sp.、Sycophilomorpha sp.、Philotrypesis sp.、Sycosapter sp.、Sycobia sp.、Ficomila sp.、Ormyrus sp.和Sycophila sp.)在果外产卵;在钝叶榕榕小蜂群落中,传粉榕小蜂占整个群落总数的62.11%,是该群落的优势种,杨氏榕树金小蜂和Lipothymus sp.分别占整个群落总数的27.19%和4.71%,其他9种非传粉榕小蜂占5.99%.钝叶榕中的非传粉榕小蜂通过各自产卵时序和幼虫食性分化的繁殖策略来分配榕果中的资源,以实现自身繁殖.非传粉榕小蜂与传粉榕小蜂的数量变化呈显著负相关,但非传粉榕小蜂与榕果内的种子没有相关性.
THE REPRODUCTIVE ECOLOGY OF FICUS CYRTOPHYLLA, AN UNDERSTORY FIG SPECIES IN XISHUANGBANNA TROPICAL RAINFOREST, CHINA
歪叶榕繁殖生态学

SHI Zhang-Hong,YANG Da-Rong,
石章红
,杨大荣

植物生态学报 , 2006,
Abstract: 该文主要从物候学、行为学和生态学3个方面首次研究报道了我国西双版纳热带雨林下的一种榕树———歪叶榕(Ficuscyrtophylla)的繁殖机制。研究结果表明,歪叶榕榕小蜂(Blastophagasp.)是歪叶榕唯一的传粉昆虫,传粉行为方式为被动传粉,而且这种榕小蜂也只能在该种榕树中成功繁衍后代。物候学观察结果表明,歪叶榕常绿且叶量常年变化较小,10~11月和3~4月是歪叶榕雄株落叶的高峰期,这时正值西双版纳的雾凉季和干热季,而雌株的落叶高峰期是3~4月;12月和5月是歪叶榕雄株新叶萌发的高峰期,而4~5月是其雌株新叶萌发的高峰期,这时正值西双版纳干热季向雨季过渡的时期,新叶萌发后同时伴随着一次该种榕树的挂果高峰期;歪叶榕在种群水平上常年持续结果,在每年的11月和4~5月有两次结果高峰期,单株每年大量结果2~3次;单棵雄株内结果异步性较高,而雌株内结果高度同步。单果进蜂数(Foundressnumber)为0~5只,大多数雄果(78.45%)和雌果(84.25%)只有1只传粉榕小蜂,大约16.02%的雄果和13.33%的雌果内含有2只传粉榕小蜂,其它情况均很少。在自然情况下,雄果中的总瘿花量为147.32±62.61(SD)枚,传粉榕小蜂出蜂量为110.94±62.82(SD)只,其中雌蜂多而雄蜂少,传粉榕小蜂性比为0.1439±0.1316(SD),瘿花形成率为64.13%±19.89%(SD),雌果中的种子数为231.44±74.25(SD)粒,种子形成率为85.72%±14.19%(SD)。歪叶榕和其传粉榕小蜂在物候学、传粉行为与花药/胚珠比(A/Oratio)和雄花成熟与其羽化出蜂的时期等方面表现出高度的相互适应。
Has Pollination Mode Shaped the Evolution of Ficus Pollen?
Gang Wang, Jin Chen, Zong-Bo Li, Feng-Ping Zhang, Da-Rong Yang
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0086231
Abstract: Background The extent to which co-evolutionary processes shape morphological traits is one of the most fascinating topics in evolutionary biology. Both passive and active pollination modes coexist in the fig tree (Ficus, Moraceae) and fig wasp (Agaonidae, Hymenoptera) mutualism. This classic obligate relationship that is about 75 million years old provides an ideal system to consider the role of pollination mode shifts on pollen evolution. Methods and Main Findings Twenty-five fig species, which cover all six Ficus subgenera, and are native to the Xishuangbanna region of southwest China, were used to investigate pollen morphology with scanning electron microscope (SEM). Pollination mode was identified by the Anther/Ovule ratio in each species. Phylogenetic free regression and a correlated evolution test between binary traits were conducted based on a strong phylogenetic tree. Seventeen of the 25 fig species were actively pollinated and eight species were passively pollinated. Three pollen shape types and three kinds of exine ornamentation were recognized among these species. Pollen grains with ellipsoid shape and rugulate ornamentation were dominant. Ellipsoid pollen occurred in all 17 species of actively pollinated figs, while for the passively pollinated species, two obtuse end shapes were identified: cylinder and sphere shapes were identified in six of the eight species. All passively pollinated figs presented rugulate ornamentation, while for actively pollinated species, the smoother types - psilate and granulate-rugulate ornamentations - accounted for just five and two among the 17 species, respectively. The relationship between pollen shape and pollination mode was shown by both the phylogenetic free regression and the correlated evolution tests. Conclusions Three pollen shape and ornamentation types were found in Ficus, which show characteristics related to passive or active pollination mode. Thus, the pollen shape is very likely shaped by pollination mode in this unique obligate mutualism.
Premature Attraction of Pollinators to Inaccessible Figs of Ficus altissima: A Search for Ecological and Evolutionary Consequences
Yuan Zhang, Yan-Qiong Peng, Stephen G. Compton, Da-Rong Yang
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0086735
Abstract: Adult life spans of only one or two days characterise life cycles of the fig wasps (Agaonidae) that pollinate fig trees (Ficus spp., Moraceae). Selection is expected to favour traits that maximise the value of the timing of encounters between such mutualistic partners, and fig wasps are usually only attracted to their hosts by species- and developmental-stage specific volatiles released from figs at the time when they are ready to be entered, oviposited in and pollinated. We found that Ficus altissima is exceptional, because it has persistent tight-fitting bud covers that prevent its Eupristina altissima pollinator (and a second species of ‘cheater’ agaonid) from entering its figs for several days after they start to be attracted. We examined the consequences of delayed entry for the figs and fig wasps and tested whether delayed entry has been selected to increase adult longevity. We found that older pollinators produced fewer and smaller offspring, but seed production was more efficient. Pollinator offspring ratios also varied depending on the age of figs they entered. The two agaonids from F. altissima lived slightly longer than six congeners associated with typical figs, but this was explainable by their larger body sizes. Delayed entry generates reproductive costs, especially for the pollinator. This opens an interesting perspective on the coevolution of figs and their pollinators and on the nature of mutualistic interactions in general.
Larger Fig Wasps Are More Careful About Which Figs to Enter – With Good Reason
Cong Liu, Da-Rong Yang, Stephen G. Compton, Yan-Qiong Peng
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074117
Abstract: Floral longevity reflects a balance between gains in pollinator visitation and the costs of flower maintenance. Because rewards to pollinators change over time, older flowers may be less attractive, reducing the value of extended longevity. Un-pollinated figs, the inflorescences of Ficus species, can remain receptive for long periods, but figs that are older when entered by their host-specific fig wasp pollinators produce fewer seeds and fig wasp offspring. Our field experiments with Ficus hispida, a dioecious fig tree, examined how the length of time that receptive figs have remained un-pollinated influences the behaviour and reproductive success of its short-lived fig wasp pollinator, Ceratosolen solmsi marchali. The results were consistent in three different seasons, and on male and female trees, although receptivity was greatly extended during colder months. Pollinators took longer to find the ostioles of older figs, and longer to penetrate them. They also became increasingly unwilling to enter figs as they aged, and increasing numbers of the wasps became trapped in the ostiolar bracts. Larger individuals were particularly unwilling to enter older figs, resulting in older figs being pollinated by smaller wasps. On female trees, where figs produce only seeds, seed production declined rapidly with fig age. On male trees, the numbers and size of fig wasp offspring declined, and a higher proportion were male. Older male figs are harder to enter, especially for larger individuals, and offer poorer quality oviposition opportunities. This study opens an interesting new perspective on the coevolution of figs and their pollinators, especially factors influencing pollinator body size and emphasises the subtleties of interactions between mutualists.
Modern testing theory and its application in the field of health measurement
Da-rong Wu
Zhong Xi Yi Jie He Xue Bao , 2012,
Abstract: ABSTRACT: This paper briefly introduces item response theory (IRT) as a typical representation of modern testing theory (MTT), and systematically reviews the processes and contents of the application of IRT in the area of health measurement, including, for example, item bank development, scale revision and computerized adaptive testing. The author presents the potential benefits and the notable problems during health measuring by IRT. Then, the author asserts the need for thorough assessment of feasibility when using the IRT in patient-reported outcome research. Further research based on IRT and computerized adaptive testing in health measurement will be carried out in the field of medical care including traditional Chinese medicine and integrative medicine.
COEVOLUTION BETWEEN TWO INTERNAL OVIPOSITING FIG WASPS AND HOST FICUS CURTIPES
钝叶榕果实内繁殖的两种榕小蜂与寄主榕树间的协同进化

ZHANG Feng-Ping,YANG Da-Rong,ZHANG Feng-Ping,PENG Yan-Qiong,YANG Da-Rong,
张凤萍
,彭艳琼,杨大荣

植物生态学报 , 2008,
Abstract: 榕树(Ficus)及其传粉榕小蜂(Agaonidae)构成了高度专一的互惠共生体系。榕树的果实(以下简称榕果)内也寄生着一些非传粉小蜂。绝大多数非传粉小蜂在榕果外把产卵器刺入果壁产卵到果腔内,只有极少数种类能够进入果腔内产卵。在西双版纳地区,钝叶榕(Ficus curtipes)上的杨氏榕树金小蜂(Diaziella yangi)类似于传粉者钝叶榕小蜂(Eupristina sp.),它也是进入榕果内产卵繁殖后代的,这就为比较研究榕果内产卵小蜂与寄主榕树间的关系提供了材料。该文从形态学、行为学和生态学角度比较研究了这两种进入榕果内产卵的小蜂与寄主钝叶榕之间的作用关系,研究结果显示:1)杨氏榕树金小蜂与钝叶榕小蜂的雌蜂头部形状存在趋同进化;2)两种小蜂的产卵器的平均长度都比雌花花柱长,因而能把卵产在子房里;3)钝叶榕小蜂从瘿花出来需要3~5h,交配需要17~19min,杨氏榕树金小蜂从瘿花出来只需18~20min,交配时间为20~30s;4)在自然群落中,大约90%的雌花期榕果里都只进一只杨氏榕树金小蜂和一只钝叶榕小蜂,杨氏榕树金小蜂能通过传粉来增加榕树种子数量,但对钝叶榕小蜂种群的繁衍造成了极显著的负面影响;5)两种小蜂于同一时期进入榕果内繁殖,子代同期成熟羽化,发育期与榕树雄花的发育期同步。研究表明:进入榕果内繁殖的两种小蜂与寄主榕树之间存在着协同进化关系,杨氏榕树金小蜂为榕树有效地传粉,这可能是一个由寄生者向互惠方向进化的实例。
Study on Pollination Ecology of Fig Wasp (Ceratosolen sp.) in the Tropical Rainforest of Xishuangbanna,China
西双版纳热带雨林聚果榕小蜂的传粉生态学

YANG Da-Rong,
杨大荣
,赵庭周,王瑞武,张光明,宋启示

动物学研究 , 2001,
Abstract: The Ficus racemosa L. (1753) is a keystone plant species in the tropical rainforest in Xishuangbanna. The fig tree ( Ficus racemosa ) and fig pollination wasp ( Ceratosolen sp ) are highly coevolved species that depend completely on mutual benefit for continued reproduction.The main result of this study indicated that the earlier emerged male wasp cut the exit holes both from the gall and fig fruit for the female,which don't have the ability to cut the exit hole for themselves. In Ficus racemosa pollen tends not to escape from the anthers after dehiscence until the stamens are disturbed by the fig wasp. The females opened the anthers with the antennal scapes,mandible,leg and collected the pollen. The pollen bored females fly about 5-80 minutes to find the receptive syconia. As soon as a pollinating fig wasp reached the interior of the young fig fruit to be pollinated,it pushed its head among the stigmas for 4-9 hours,then oviposited in the short stigmas(gall flowers) of the fig.
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