Isolation of de-exined pollen and cytological studies of the pollen intines of Pinus bungeana Zucc. Ex Endl. and Picea wilsonii Mast

To study the cytological and biochemical characteristics of intine, pollen deprived of exine, or de-exined pollen, was isolated from the gymnosperms Pinus bungeana and Picea wilsonii. The factors influencing the isolation rate were examined. Cellulose, callose, pectin, and arabinogalactan proteins (AGPs) were localized in this material using fluorescent probes, and components of the isolated intine were further analyzed by Fourier transform infrared (FTIR) microspectroscopy. The isolation protocol was repeatable and reliable. Cellulose was found to be evenly distributed on the surface of the intine, as indicated by strong calcofluor White ST (CW) fluorescence, and aniline blue staining revealed that callose was present on the intine of P. bungeana but not on that of P. wilsonii. Immunolabeling revealed that acidic pectin epitopes recognized by the monoclonal antibody JIM5 were present on the pollen intine, as well as esterified pectin recognized by the monoclonal antibody JIM7, and AGPs recognized by the LM2 antibody. Two lectin binding sites, the concanavalin agglutinin (Con A) and soybean agglutinin (SBA) binding sites, were present on the intine surface, but no wheat germ agglutinin (WGA) binding sites were detectable. These results were confirmed by FTIR analysis.     

Determinants of pollen dispersal in the East Asian steppe at different spatial scales

Two sites from the East Asian steppe, the Mu Us Sandland as a regional case and the Anguli Nuur catchment as a local one, were chosen to detect roles of vegetation, climate, landform, and human disturbance on pollen dispersal. 1) Vegetation: The semi-arid steppe vegetation is characterized by Artemisia and Chenopodiaceae pollen under various vegetation conditions; however, no evident correlation between pollen percentages and corresponding plant species cover is found. 2) Climate: Samples under different Mean Annual Precipitations (MAPs) clearly distinguish themselves in the Mu Us Sandland, implying MAP-determined surface pollen spectra in regional scale. 3) Landform: Surface pollen assemblages in the azonal psammophytic vegetation and lowland meadow, show insignificant variance from the zonal steppe vegetation. The azonal halophilous vegetation, mostly distributed in the lowland or near the lake shore, leads to higher than average percentages of Chenopodiaceae pollen. Signal of exotic Pinus pollen is also strengthened in the lowland and lake sediment. 4) Human disturbance: The role of human disturbance on surface pollen assemblages is weak, as shown in the Mu Us Sandland.

This study also provides theoretical bases for quantitative reconstructions of palaeoclimate and palaeovegetation based on fossil pollen spectra from lake sediments and lowland soils in the semi-arid East Asian steppe. We suggest that calibration against locally dispersed pollen taxa is necessary to reliably reconstruct changes in vegetation pattern through time, for example, a factor of 1.75 for the widely used A/C (Artemisia/Chenopodiaceae) ratio is suggested according to the pollen assemblages in the surface layers of the lake sediment vs. slope soil in Anguli Nuur. However, uncertainties also exist for such calibration considering the dynamics of local-scale azonal vegetation.     

Pollen as a source of food for egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae)

The value of corn pollen as a food source for Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae) was assessed in the laboratory by testing the effect of different pollen diets on the longevity, capacity of parasitism and other life-table parameters. T. brassicae females that fed on corn pollen and water (wet filter paper dusted with pollen) lived significantly longer (4.97 days) than females that fed on water alone (2.67 days), but significantly shorter than those feeding on honey alone (8.37 days) or corn pollen and honey (8.23 days), respectively, in the absence of host eggs. The presence of European corn borer eggs (Ostrinia nubilalis Huebner, Lepidoptera: Pyralidae) significantly increased longevity. With host eggs available, female T. brassicae that fed on corn pollen and water lived significantly longer (4.9 days) than on water alone (2.60 days), but significantly shorter than on honey alone (12.33 days) or corn pollen and honey (12.17 days), respectively. The cumulative lifetime fecundity was 82.53 offspring pupae when fed on pollen and water, which was significantly higher than 61.70 for water alone but lower than feeding on honey alone (95.70) or corn pollen and honey (99.97), respectively. Compared to water alone, corn pollen and water increased the net reproduction rate (R₀), intrinsic rate of increase (r_m), and finite rate of increase (λ), and reduced the doubling time (T₂), but had no effects on the emergence rate, sex ratio, and mean generation time (T_c). In another set of experiments, 13 out of 30 females reduced the number of pollen grains offered to them. The average number of pollen grains utilized per female in this 48-h test 2.46±0.40 (mean±SE). Hence, T. brassicae used corn pollen as food that significantly increased longevity and fecundity of the tested females. Pollen and honey supplied a complete diet for T. brassicae, compared to pollen and water or water alone.     

An abbreviated method for the quality control of pollen counters

We present an abbreviated method for conducting large scale quality control (QC) exercises over limited time periods, which was used for examining the proficiency of technicians involved in the electronic Pollen Information Network (ePIN). The goal was for technicians to have their analysis skills evaluated at least twice: (1) by having at least one of their slides successfully checked by other counters in the ePIN network and (2) by successfully examining at least one additional slide from other sites. Success was judged as a relative difference (RDif %) ≤ 30% between the two daily average pollen concentrations. A total of 21 sites participated in the ePIN QC exercise. All of the results for total pollen had RDif % < 30%. Only five results had RDif > 30%, three for Betula and two for Poaceae pollen. Of these, three were slides containing < 40 pollen/m³ daily average and two were for sites that had microscopes with small fields of view and examined < 10% of the slide surface. More than 80% of the participants had at least two slides successfully checked by someone else in the network, and all of the participants had one slide successfully examined. The latter is comparable to a traditional ring test where only one slide is sent to participating sites. The method described here enabled a large number of technicians to be examined in a short period of time and represents a viable alternative to other approaches that can take many months to complete.     

束花石斛的繁育生物学特性

为了探究束花石斛（Dendrobium chrysanthum）的繁育生物学特性,对其开花习性、花粉活力、柱头分泌特性、人工授粉结实率、自然结实种子育性和贮藏特性进行研究,结果表明：（1）束花石斛花芽萌动期为19 d,现蕾期为23 d,群体花期为28 d,单花寿命10~15 d;（2）开花1~3 d花粉活力保持在90%左右,开花至第9天时花粉活力仅为23.7%,初始3 d开花的花粉活力与其他时间取样的活力差异均达极显著水平（P<0.01）,花粉活力随开花时间延长呈由强到弱的趋势;（3）束花石斛的柱头腔从开花第2天开始有分泌物,第6 d时分泌物最多,柱头过氧化氢染色结果表明在开花5~6 d时柱头可授性最强,柱头可授性随开花时间延长呈由弱到强再到弱的趋势;（4）选取花朵开放4 d的花粉和柱头人工授粉,同株异花和同花授粉未见结实。野外结实果质量2.02~4.83 g,种子长0.628~0.845 mm,宽0.082~0.110 mm,长宽比为7.798,成胚率达97.35%,种子活力为90.80%,室温条件保存6个月的种子活力维持在73.20%。上述结果说明,束花石斛单花花期不长,开花初期花粉活力最高,柱头发育要滞后于花粉的发育;束花石斛不存在无融和生殖,人工同株自花授粉不育。但自然状况下能正常结实,种子发育良好,胚活力较高,干燥种子在自然条件下有一定的耐贮特性。本研究揭示了束花石斛的开花生物学特性和雌雄蕊异熟特点,其交配系统应为自交不亲和,为其野生种质资源的保育和人工精准授粉提供科学依据。     

Intraspecific variation in morphology of spiny pollen grains along an altitudinal gradient in an insect-pollinated shrub

• Intraspecific variations in pollen morphological traits are poorly studied. Interspecific variations are often associated with pollination systems and pollinator types. Altitudinal environmental changes, which can influence local pollinator assemblages, provide opportunities to explore differentiation in pollen traits of a single species over short distances. The aim of this study is to examine intraspecific variations in pollen traits of an insect-pollinated shrub, Weigela hortensis (Caprifoliaceae), along an altitudinal gradient.
• Pollen spine phenotypes (length, number and density), pollen diameter, lipid mass (pollenkitt) around pollen grains, pollen production per flower and pollinator assemblages were compared at four sites at different altitudes.
• Spine length and the spine length/diameter ratio of pollen grains were greater at higher altitudes but not correlated with flower or plant size. Spine number and density increased as flower size increased, and pollen lipid mass decreased as plant size increased. Bees were the predominant pollinators at low-altitude sites whereas flies, specifically Oligoneura spp. (Acroceridae), increased in relative abundance with increasing altitude.
• The results of this study suggest that the increase in spine length with altitude was the result of selection favouring longer spines at higher-altitude sites and/or shorter spines at lower-altitude sites. The altitudinal variation in selection pressure on spine length could reflect changes in local pollinator assemblages with altitude.

     

青篱柴通过促进亲和花粉生长而提高传粉精确性

异型花柱植物的适应意义在于提高亲和花粉的传递, 从而促进异交, 但是有不少研究发现柱头上落置了大量不亲和花粉。目前, 很少有人研究柱头是否有利于亲和花粉的萌发和花粉管伸长, 以及通过去雄处理排除花内和植株内不亲和花粉干扰从而验证二型花柱植物是否可以促进异交。本研究以亚麻科青篱柴属(Tirpitzia)的二型花柱植物青篱柴(T. sinensis)为研究对象, 分居群调查了青篱柴长、短柱型的植株数量, 测量不同柱型的花粉与柱头大小以及观察其表面纹饰, 测定不同开花时间长、短柱型的柱头活性与花粉活力, 统计自然状态下柱头上落置的不同表型花粉比例, 进一步统计花内、株内去雄和自然对照下柱头上落置的不同表型花粉比例, 计算型间、型内和混合授粉花粉管长度和花粉萌发率, 人工授粉检测其是否型内异交不亲和与自交不亲和。结果表明, 自然居群中长、短柱型青篱柴植株数量没有显著性差异; 短柱型青篱柴花粉体积显著大于长柱型, 且二者花粉表面纹饰不同, 但不同柱型的柱头表面积与表面纹饰无差异; 青篱柴开花第一天的花粉活力显著高于开花第二天, 而柱头活性在开花前两天无显著性差异; 自然状态下柱头上落置的不亲和花粉比例显著高于亲和花粉; 在长柱型青篱柴中, 花内和株内去雄显著提高了柱头上亲和花粉的落置比例; 柱头上授型内花粉, 其花粉萌发率和花粉管的长度都显著低于授型间花粉; 授粉结果表明青篱柴为型内异交不亲和与自交不亲和。二型花柱植物通过促进亲和花粉的萌发和花粉管的伸长而有利于型间授粉, 从而显著提高其传粉精确性。     

Preliminary study on pollen distribution in the surface soil of the Turpan region in the southern slope of Tianshan Mountains,Xinjiang, China

Aims Our main purposes were to analyze the relationship between vegetation and pollen in the surface soil of the Turpan region, which is located in the southern slope of the eastern Tianshan Mountains, and to compare different pollen assemblages between the Turpan region and the northern slope of the Tianshan Mountains.Methods We collected 36 modern pollen samples and carried out modern vegetation survey in the Turpan region along an altitudinal gradient from 2 000 m to -154 m. Detrended correspondence analysis and Redundancy analysis were applied to analyze the distribution pattern of pollen in surface soils. Important findings We divided the pollen spectra into four pollen assemblage zones (mountain desert-steppe and desert, Gobi gravel, typical desert and salt mash vegetation), corresponding to the major vegetation types in the Turpan region. When compared with the northern slope, the characteristics of pollen assemblages in the mountain desert-steppe and desert were similar to those in the forest-steppe on the northern slope of the Tianshan Mountains; the pollen assemblages in the Gobi gravel and the typical desert seemed to be more consistent with those in the typical desert on the northern slope; however, no analogue was found in the salt mash vegetation. Obviously, the vertical pollen spectra in Turpan region were incomplete, lacking typical forest and Artemisia desert pollen zones. Besides, similar pollen zones in the Turpan region were found at an elevation of about 300 m higher than those in the northern slope. It is remarkable that the typical tree pollen, such as Picea and Pinus, showed their extra representation in the Turpan region. On one hand, the valley forest on the southern slope of the Tianshan mountains played an important role in pollen dispersal. On the other hand, with the cold air on the northern slope over the Tianshan Mountains, pollen may be carried and deposited in the Turpan region. The rivers feeding into Aiding Lake in the Turpan region may also contribute to the distribution of Picea and Pinuspollen. Lots of pollen studies have shown that the ratio of Artemisia to Chenopodiaceae (A/C) can be used as a good indicator of the degree of humidity in the semi-arid and arid areas. Our study revealed that A/C can roughly reflect the characteristics of the desert zone in the study area. The results of Redundancy Analysis ordination on pollen assemblages and environmental factors (mean annual temperature (MAT), mean annual precipitation (MAP) and altitude (ALT)) revealed that MAP was the main environmental factor affecting the pollen assemblages in the surface soil in the Turpan region and had more significant effects on the distribution of Nitraria pollen than on the distribution of Artemisia and Chenopodiaceae.     

Numerical modelling of pollen dispersion on the regional scale

New parameterisations were developed to calculate the emission and resuspension flux of pollen grains. These new parameterisations were included in the comprehensive mesoscale model system KAMM/DRAIS. Two types of simulations were performed. In the first case, horizontally homogeneous meteorology was assumed. In this case, pollen concentration rapidly decreased with the distance from the source. In the second case, where the fully three-dimensional model was applied, atmospheric lifetime of the pollen grains increased remarkably. This was mainly caused by the vertical wind speeds induced by topographic effects. Consequently, the pollen grains could travel much larger distances until they were deposited and finally removed from the atmosphere. This is an important finding with respect to the problem of cross pollination. Due to the lack of measurements, a number of parameters had to be assumed. However, the parameterisation proposed may well serve as a starting point of a daily pollen forecast with numerical models.     

15个小苍兰品种的花粉形态研究

以15个小苍兰品种为试材,利用场发射扫描电镜（SET）对其进花粉形态观察,通过对花粉形状、大小、外壁纹饰及萌发器官等特征,分析不同品种间花粉形态之间的异同。结果表明：15个小苍兰品种的花粉均呈单粒存在且两侧对称,具远极单沟萌发孔,花粉外部形态均呈椭球形,极面观为舟形或心形,赤道面观除Castor外均为超长球形。花粉外壁纹饰均有小刺状凸起,多数品种表面有小穿孔和圆形斑纹。进一步聚类分析表明,15个小苍兰品种根据花粉形态特征可以分成3大类。本文首次报道了小苍兰的花粉形态,并且发现,不同品种间花粉形态特征具有一定差异,尤其是外壁纹饰细部特征和萌发器官的差别,体现了不同小苍兰品种间存在一定的遗传多样性和遗传分化,可为今后分析品种间亲缘关系及种质创新等提供有价值的科学依据。     

DNA uptake during electroporation of germinating pollen grains

Electroporation of germinating pollen grains of Nicotiana gossei (L.) Domin under a variety of conditions showed that DNA was taken up by the pollen without detrimental effects on the viability of the pollen. By optimizing both the field strength of the electroporation pulse and the DNA concentration in the electroporation medium up to 6% of the donor DNA can be taken up by the germinating pollen while maintaining a pollen viability of 90%. Field strengths as high as 9 kV/cm could be applied to germinating pollen grains without detrimental effects on viability. Southern hybridizations demonstrated that DNA encoding the marker enzyme β-glucuronidase (GUS) was incorporated into electroporated pollen. Germinating pollen, treated in this manner, is capable of producing 300–400 seeds per capsule of viable seed when applied to the stigmas of compatible flowers of N. gossei which has been emasculated 4 days earlier.     

铁皮石斛花粉块结构及发育过程的解剖学特征研究北大核心CSCD

兰科植物的有性生殖特殊,每朵花只有1个花药,且花粉有聚集成块发育的特征。为了揭示铁皮石斛花粉块的发育特征,该研究以野生铁皮石斛不同时期的花药为材料,采用半薄切片和植物组织化学方法对其发育过程进行解剖学观察分析,并对成熟花粉块进行离体培养,观察花粉管的萌发状况。结果表明:(1)铁皮石斛花药壁由1层表皮细胞,2层药室内壁细胞,1层中层细胞和1层绒毡层细胞组成。开花时,绒毡层细胞退化,中层细胞没有退化,药室内壁细胞则形成纤维状细胞壁;药室中的小孢子母细胞没有明显的胼胝质壁结构。(2)小孢子发生属同时型,减数分裂后四分体小孢子不分散,以四合花粉状态发育,并进一步连接形成花粉块。(3)在小孢子发育中,孢粉素覆盖在整个花粉块表面形成花粉外壁,但花粉块内部的花粉没有花粉外壁结构;在花粉块表面的花粉外壁上未见花粉萌发孔。(4)在花粉离体萌发实验中,具有花粉外壁的花粉块表面花粉未见萌发,仅由花粉块内部的花粉萌发出花粉管。     

中国15种变豆菜属植物的花粉形态及系统学分析

利用光学显微镜和扫描电子显微镜对变豆菜属15种植物的花粉形态进行观察。结果表明,变豆菜属15种植物的花粉大小为（28.51~54.29） μm~（12.23~28.98） μm,极轴与赤道轴比值（Polar axis/Equatorial axis）为1.48~2.46,具三孔沟。花粉粒赤道面观有近矩形、赤道收缩形、长椭圆形等类型,其中近矩形和赤道收缩形占多数;极面观为圆形或三角圆形。在扫描电镜下,其外壁表面纹饰为网状。我们研究结果支持在伞形科变豆菜亚科中,变豆菜属植物的花粉具有中等进化、比较进化的形态特征,花粉形态可为个别物种的分类处理提供孢粉学证据。     

Northern Hemisphere megafossil of Dacrycarpus (Podocarpaceae) from the Miocene of South China and its evolutionary and paleoecological implications

The modern genus Dacrycarpus (Endl.) de Laub. of the family Podocarpaceae, containing nine species, is mainly distributed in tropical mountain rainforests of the southwestern Pacific region, ranging from New Zealand to low‐latitude Asia. This genus has abundant fossil records in both hemispheres, but all the known megafossils were limited to Australasia and South America. Here we report on Dacrycarpus guipingensis sp. nov. from the Miocene Erzitang Formation of Guangxi, South China. This is the first megafossil of Dacrycarpus in the Northern Hemisphere. The new species is represented by mummified dimorphic foliage, ovuliferous shoots, and a male cone with in situ pollen. It resembles the extant Dacrycarpus imbricatus (Blume) de Laub., which is common in rainforests from southern China and northern Myanmar to Fiji. This paper presents the first data on the anatomical structure of seed cone and exine ultrastructure of Dacrycarpus in situ pollen grains from a fossil material by using computed tomography scanning and ultrathin sectioning. For comparative purpose, data on the pollen morphology and ultrastructure were obtained for modern D. imbricatus for the first time. The D. guipingensis fossils strongly suggest the Miocene arrival of Dacrycarpus in Asia from the Southern Hemisphere. Based on the modern ecological niche and related fossil elements, this fossil locality was probably covered by conifer–broad‐leaved mountain rainforests during the Miocene.     

Secondary pollen presentation: More than to increase pollen transfer precision

Pollination precision and efficiency have been deemed to be important driving forces in floral evolution. Herkogamy reduction is a main mechanism to increase pollination precision. Secondary pollen presentation (SPP), by which pollen is presented on other floral organs especially pistils, has been widely accepted as a special mechanism to increase pollen transfer precision through spatial reduction of the anther–stigma distance, that is, minimized herkogamy. This overlooks a potential driving force, that is expanding the pollination niche through converting pollen thieves and nectar robbers into effective pollinators. We selected two species as study models with typical pistillate SPP, Pavetta hongkongensis Bremek. (Rubiaceae) and Scaevola taccada (Gaertn.) Roxb. (Goodeniaceae). In both species, two distinct pollinator functional groups were recognized. Short-tongued bees and flies fed on pollen on stigmas but also stole pollen from anthers and robbed nectar, whereas long-tongued hawkmoths and butterflies only collected nectar. Emasculation had no influence on long-tongued pollinators, but significantly decreased the visitation frequency of short-tongued visitors and fruit set, compared to intact flowers, demonstrating short-tongued visitors did not effectively pollinate and acted merely as pollen thieves or nectar robbers when SPP was absent. Data from the two plant species clearly indicated pistillate SPP has additional adaptive advantages of converting ineffective visitors into pollinators and consequently widening the pollination niche, which could help plants overcome environmental stochasticity. Our results suggest that multiple selective forces drive the evolution of SPP and the minimization of herkogamy.     

Response of pollen diversity to the climate-driven altitudinal shift of vegetation in the Colombian Andes

Change in diversity of fossil pollen through time is used as a surrogate for biodiversity history. However, there have been few studies to explore the sensitivity of the measured pollen diversity to vegetation changes and the relationship between pollen diversity and plant diversity. This paper presents results of a study to assess the relationship between pollen diversity and relative abundance of pollen from different altitudinal vegetation belts (subandean forest, Andean forest, subparamo and grassparamo) in three records from the tropical Andes in Colombia. The results indicated that plant diversity in the vegetation declined with altitude and pollen diversity is positively correlated to the abundance of pollen from lower altitude vegetation belts and negatively correlated to that from the grassparamo. These results, therefore, suggest that pollen diversity coarsely reflects the diversity of the surrounding vegetation. Using this interpretation, we were able to predict changes in plant diversity over the past 430000 years in the Colombian Andes. Results indicated that under warmer climatic conditions, more species-diverse vegetation of low elevation moved upslope to contribute more pollen diversity to the study sites, and under colder conditions, species-poor grassparamo moved downslope and observed pollen diversity was lower. This study concludes that fossil pollen diversity may provide an important proxy to reconstruct the temporal changes in plant diversity.     

Altitudinal variation in the reproductive performance of the Mediterranean shrub Rhamnus lycioides L.

Aims Rhamnus lycioides L. subsp. Oleoides (Rhamnaceae) is a perennial shrub native to the Mediterranean Basin distributed along an altitudinal gradient, from sea level up to 1?000 m a.s.l. The specific goals of our study were (i) to compare plant morphology between two contrasting populations, (ii) to determine the reproductive system of R. lycioides, quantifying the relative importance of insects and wind as pollen vectors, (iii) to test if pollen limitation differs between populations, (iv) to study the main factors influencing fruit set and (v) to compare plant reproductive performance (mass allocation to flowers, fruits and seeds) between the two habitats.Methods In the present study, we examined plant morphology and the reproductive performance of R. lycioides L. in contrasting environments in two populations located at the extremes of its altitudinal range in the island of Mallorca (Balearic Islands, Western Mediterranean Basin) along a 3-year period. Plant morphology, the relative importance of insects and wind as pollen vectors, the pollen limitation to seed production and the plant reproductive performance (mass allocation to flowers, fruits and seeds) were determined.Important findings Rhamnus lycioides individuals showed a higher plant surface/plant height ratio at the mountain than at the coast. This species appeared to be ambophilous despite its inconspicuous flowers, although the relative importance of wind as a pollination vector was higher at the mountain than at the coastal site. Fruit set was much higher at the mountain, where pollen appeared to be a limiting factor. By contrast, fruit set was not limited by pollen availability at the coastal population, where resource (water and nutrients) limitation seemed to be more determining. Flower size was greater at the coast, in contrast to fresh fruit weight that was higher at the mountain. Despite the relatively few differences between sites in precipitation patterns along the study period, water availability appeared to be the key factor explaining not only fruit set but also the reproductive performance of this species in the study populations.     

西天山南坡表土花粉分析

通过对西天山南坡不同植被带52个表土花粉样品的鉴定,研究表土花粉组合与现代植被分布的关系,分析蒿属/藜科比值(A/C)在该区域的指示意义.结果表明:山顶至山底可以划分为5个植被带,分别为高山荒漠带、高山草甸带、草甸草原带、山地荒漠带、典型荒漠带,代表性科属为蒿属、藜科、禾本科和麻黄属,该区域不同植被类型表土样品花粉组合差异明显.西天山南坡表土花粉在一定程度上受到北坡的影响,海拔越高影响越大.A/C值随海拔升高而先升高再降低,在高山草甸区域达到最高,可以作为反映山地垂直方向气候干湿变化的有效指标.由于A/C值波动较大,利用该比值进行气候环境重建时,需注意受人类活动等因素影响所产生的高值可能带来误判.     

利用昆虫携带的花粉初探西藏入侵植物印加孔雀草在当地传粉网络中的地位

入侵植物在新生境中成功定殖后, 通过利用当地传粉昆虫促进繁殖可以更好地保证种群的扩张, 但是入侵植物在当地传粉网络中的角色和地位仍不是很清楚。本文利用西藏近年发现的入侵植物印加孔雀草(Tagetes minuta), 分析其访花昆虫所携带的植物花粉种类, 构建了植物花粉-传粉者网络, 探讨印加孔雀草快速入侵和扩张的可能机制。结果表明印加孔雀草为泛化传粉系统, 共有13种昆虫访花, 其中12种携带有印加孔雀草花粉, 所有花粉中印加孔雀草花粉数量占比为89.89%。12种印加孔雀草传粉昆虫中, 4种泛化传粉昆虫(1种蜂、2种食蚜蝇和1种蝇)是其主要传粉昆虫。本研究揭示印加孔雀草在较短时间内已经成功利用多种当地泛化传粉昆虫为其授粉, 已顺利融入当地的传粉网络, 今后需要更加重视对印加孔雀草的防控。