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51.
The aerobiological behaviour of Urticaceae in Trieste and the correlations with the meteorological parameters were examined. Airborne pollen was collected from 1990 to 1999 using a Hirst type spore trap (Burkard) and the data interpretation was performed according to the standard method adopted by the Italian Aeroallergen Network. The main pollen season of Urticaceae in Trieste goes from mid-April to mid-September. The highest values occur in May and June. Although different seasonal patterns are found every year, the main peak occurs on average at the beginning of May, followed by other decreasing peaks until September. Thecumulative counts vary greatly over the years, with a mean value of 18.315 p/m3. The maximum annual total pollen grains was registered in 1996 and the minimum in 1991. Spearman's correlation was used to establish the relationship between the daily pollen counts and the daily meteorological data both considering their original quantitative values and transformed values according to their day by day changes. Daily pollen concentrations present usually positive correlation with temperature, negative with rainfall and wind speed and no correlation with humidity. Better results were obtained with transformed values. 相似文献
52.
广西楼梯草属五新种 总被引:6,自引:5,他引:1
描述了在中国广西发现的楼梯草属五新种:小果楼梯草Elatostema microcarpum W.T.Wang & Y.G.Wei在体态方面与荔波楼梯草E.liboense W.T.Wang极为相似,但茎较低矮,不具软鳞片,叶上面无毛,钟乳体较小而可区别。圆序楼梯草Elatostema gyrocephalumW.T.Wang &Y.G.Wei在体态上与浅齿楼梯草E.crena-tum W.T.Wang相似,但叶两面均有糙伏毛,侧脉较少,4-6对,钟乳体较小,长约0.1 mm而不同。对序楼梯草 Elatostema binatum W.T.Wang &Y.G.Wei在亲缘关系方面与深绿楼梯草E.atroviride W.T.Wang相近,但茎和叶无毛,雄花序托较小,近方形,长度及宽度约6.5 mm,小苞片较小,长约1.5 mm,无毛,可以区别。河池楼梯草Elatostema hechiense W.T.Wang &Y.G.Wei似华南楼梯草E.balansae Gagnep.但叶的渐尖头全缘,钟乳体较小,长0.1-0.15 mm,雌花序苞片顶端无角状突起,可以区别。环江楼梯草Elatostema huanjiangense W.T.Wang & Y.G.Wei可能与樟叶楼梯草Elatostema petelotii Gangnep.有亲缘关系,但后者的叶全缘,钟乳体较大,长0.3-0.7 mm,侧脉在狭侧3条,在宽侧4条,但后者的叶全缘,钟乳体较大,长0.3-0.7 mm,侧脉在狭侧3 条,在宽侧4条,雌花序常有长花序梗,而与本种相区别。 相似文献
53.
Wang Wen-Tsai 《植物分类学报:英文版》1990,28(4):307-320
In the present paper two series, 11 species and three varieties of the
genus Elatostema are described as new from China and one variety is elevated to specific rank. Four species and one variety are reported from Medog, Xizang Autonomous Region, for the first time. 相似文献
54.
Immunological comparisons of higher plant plastocyanins 总被引:1,自引:0,他引:1
Antisera were prepared in rabbits to purified plastocyanins of Spinacia oleracea and Urtica dioica. Using the method of micro-complement fixation, the immunological cross-reactivity of these antisera with plastocyanins from 37 species of plants was determined. Cross-reactivity between antisera to spinach plastocyanin and 11 plastocyanins from other plant species showed a positive correlation with distance on an ancestral amino acid sequence affinity tree constructed by the method of Dayhoff and Eck [1]. The importance of serological data as a supplement to amino acid sequence data in evolutionary studies is discussed. 相似文献
55.
Elatostema suzukii , an endemic species occurring only along streams in the Yanbaru area in the north of Okinawa Island, the Ryukyus, is known
to comprise di-, tri-, and tetraploids with x=13. Molecular analysis of chloroplast DNA sequences has shown that two haplotypes, AT- and NI-types, characterized by the
insertion or deletion of four nucleotides “ATAT”, exist in E. suzukii. The AT-type was found in some diploids and triploids only at Genkagawa, whereas the NI-type is widespread, occurring in
both diploids and triploids of the Genkagawa site as well as at other localities. The triploids share both types with the
diploids, indicating that the triploids have at least two independent origins. Because of its restricted distribution, the
AT-type triploid may have arisen within the Genkagawa area.
Received 16 October 2000/ Accepted in revised form 18 June 2001 相似文献
56.
对产自越南的荨麻科楼梯草属植物一新种金喜楼梯草(Elatostema kimhyense Y.G.Wei & V.T.Do)作了描述和绘图。该种生长于海拔350~400和1 100~1 200 m的石灰岩山地林下。该新种与越南楼梯草(E.vietnamense Q.Lin & L.D.Duan)接近,区别在于其拥有肉质茎,羽状脉,叶背面、苞片和小苞片被微硬毛。 相似文献
57.
Galán C Alcázar P Cariñanos P Garcia H Domínguez-Vilches E 《International journal of biometeorology》2000,43(4):191-195
The influence of meteorological factors on daily Urticaceae pollen counts were studied in Córdoba (southwest Spain) in 1996
and 1997. The daily Urticaceae pollen concentrations were obtained by using a Hirst-type volumetric sampler, and meteorological
data were obtained from the Córdoba airport, located near the sampling site. The highest correlation between pollen concentration
and meteorological parameters was obtained during non-rainy seasons. Temperature was found to be the most important meteorological
parameter influencing pollen counts in spring, as temperature is the main reason for the increase of pollen concentration
in the atmosphere. In autumn, humidity was another important parameter influencing pollen counts. Rain, however, did not appear
to be significant. The influence of the pollen concentration of the 2 previous days and the pollen concentration of the previous
day has been studied. During periods with low precipitation, the pollen concentration of the previous day was a useful predictor
of Urticaceae pollen concentrations for the following day.
Received: 4 January 1999 / Revised: 26 July 1999 / Accepted: 6 September 1999 相似文献
58.
描述了从云南东南部发现的荨麻科楼梯草属二新种,其中黄连山楼梯草隶属于骤尖楼梯草组骤尖楼梯草系,腺点楼梯草隶属于骤尖楼梯草组盘托楼梯草系。 相似文献
59.
60.
Summary Annual differences in cumulative counts of Urticaceae pollen are found to relate primarily to the weather conditions during
the pollen formative period (April and May) and secondarily to the weather prevailing during the season itself. Relative humidity,
temperature, wind velocity and precipitation emerge as the most influential variables in the analysis of daily variations
but their relative importance varies between years. Diurnal patterns in concentrations show general peaks occurring in the
early evening but the severity and exact timing of these relates closely to wind direction. The implications of these results
are considered in the context of forecasting. 相似文献