Air pollution effects on structure,proteins and flavonoids in pollen grains of Thuja orientalis L. (Cupressaceae)

Increase in the levels of air pollution due to the increase in industrial and agricultural technology has prompted investigation of mechanisms that contribute to air pollution tolerance in plants. Pollen grains of Thuja orientalis were collected from controlled (less polluted) and polluted areas (mainly SO₂, NO₂, CO, HC and APM). Thuja pollen is considered inaperturate and granulate. The exine is shed during rehydration, leaving the male gametophyte naked. The pollen grains collected from polluted areas are smaller and more fragile compared to control ones. The exine splitting is faster and higher in polluted pollen grains. SDS–PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis) pattern do not show significant differences in polluted pollen than those in the control group. HPLC (high pressure liquid chromatography) analysis demonstrates that air pollution induces flavonoids accumulation to significantly higher levels in polluted pollen than in controlled ones. These observations suggest that plants try to respond suitably by adjusting their metabolism so that minimum damage is done due to air pollutants. Their protective responses may include an increase in antioxidant enzymes and metabolites and induction of protection-related secondary metabolite genes especially flavonoids.     

A study on the allergenicity and ontogeny of Acacia farnesiana pollen grains in guinea pigs

Pollen grains as the angiosperm male gametophytes transfer male genetic material during sexual reproduction. Pollen grains are among the important plant allergens, such that almost 80–90 % of plant allergens are of pollen origin. Acacia farnesiana is a plant with economical values, and due to its resistance to dry climates, it has had a widespread distribution in Southern Iran. This study was aimed at investigating the allergenicity and the ontogeny of pollen grains of A. farnesiana. Pollen grains were collected from the blossoms and flowers of A. farnesiana in the suburbs of Ahvaz-Iran. Pollen extracts (15 %) were prepared in PBS (pH 7.2). 4–6-week-old male guinea pigs (Hartly) were used for allergenicity tests. Skin tests showed a significant increase in flare diameter. Clinical tests also showed a significant change in the levels of eosinophils, neutrophils, and IgE. Histotechnical analysis was performed on male gametophytes, and photographs were taken using a camera-equipped light microscope. Pollen characteristics were identified using both light and electron microscopy. Sporoderm ultrastructure and pollen morphology were studied using Scanning Electron Microscopy. PAGE analysis of the total protein content of mature pollen grains showed seven clear bands of 10–83 kDa.     

Comparative aerobiology,allergenicity and biochemistry of three palm pollen grains in Calcutta,India

A Burkard volumetric trap was used at Salt Lake City, Calcutta, to record the occurrence and frequency of three common palm pollen, namely,Areca catechu, Borassus flabellifer andPhoenix sylvestris for two consecutive years (July 1988–June 1990). The meteorological factors responsible for the frequency of relevant airborne pollen grains were analysed. The allergenic potential of these pollen types was investigated by skin-prick tests on adult respiratory allergic patients. These were also chemically analysed in terms of total carbohydrate, lipid and soluble protein. Total soluble protein of the above types was used in 11% SDS-polyacrylamide gel electrophoresis to study the range of molecular components.     

A comparative study on the allergenicity, structure, and ultrastructure of two Acacia pollen grains in guinea pigs

Acacia saligna and Acacia victoria are native to Australia brought to and grown in Southern Iran. They have since had a widespread distribution and become native in Iran. As people of the region are exposed to the pollen grains from these plants during a 5 months period, this study aimed at investigating the allergenicity of their mature pollen grains. In addition, the structural and ultrastructural as well as the total protein content of the mature pollen grains were analyzed. Pollen grains of A. saligna and A. victoria were collected from the suburbs of Ahvaz, Iran. Pollen extracts (15 % concentration) were prepared in PBS (pH 7.2), and 4- to 6-week-old male guinea pigs (Hartly) were used for allergenicity tests. Skin tests showed a significant increase in flare diameter. Clinical tests also showed a significant change in the levels of eosinophils, neutrophils, and IgE. Comparative analysis of the allergenicity of A. saligna and A. victoria pollen grains revealed a higher IgE level in the latter. Comparative analysis of pollen characteristics was performed using both light and electron microscopy for sporoderm structure and ultrastructure, respectively. Twelve percent PAGE analysis of the total protein content of mature pollen grains showed a greater number of bands in A. victoria, while four bands were common in both species. In conclusion, this study demonstrates that both A. saligna and A. victoria pollen grains are allergenic, with a greater allergenicity of A. victoria pollen grains. In addition, the structural and ultrastructural as well as the total protein content of the mature pollen grains are revealed, and a potential protein allergen is proposed.     

Transfusion Tissue in the Leaves of Thuja orientalis L.

The studies on the development and structure of transfusiontissue in the leaves of Thuja orientalis L. reveal that thetransfusion tissue develops all around the vascular bundle andforms a broad wing-like structure on either side of the midrib,in almost the entire length of the leaf. It extends beyond thevascular strand and reaches the apex where it is reduced considerably. The transfusion tissue in T. orientalis is of complex natureand is composed of living and non-living elements. The formerincludes transfusion parenchyma and albuminous cells while thelatter only the tracheids. Both vary in their size and shapeat various positions within a leaf.     

侧柏和北美香柏(柏科)的传粉机制(英)

观察了侧柏（Phaycladusorientalis（L．）Franco）和北美香柏（ThujaoccidentalisL．）散粉后花粉进入珠孔的过程。在散粉期,这两种植物的胚珠均分泌出传粉滴。当花粉落到传粉滴上后,引起传粉滴表面的形状发生改变或减弱胚珠的继续分泌,使得该传粉滴蒸腾加快,导致其比未授粉的传粉滴明显收缩。观察结果表明：不同植物的花粉导致侧柏传粉滴的收缩速率不尽相同。其中,与侧柏亲缘关系较近的植物花粉引起传粉滴的收缩速率和侧柏自身花粉引起的传粉滴收缩速率相似;反之,收缩速率变慢。侧柏传粉滴的收缩可能主要是由于花粉减弱胚珠分泌的结果。     

Outdoor and indoor pollen grains in sofia

For frequently two years a period of the range and quantity of pollen grains in the most inhabited rooms of each of 4 dwellings in Sofia was studied, together with the outdoors air pollen spectra. Changes in the health status of the inhabitants affected by pollinosis were recorded at the same time. The characteristic pollen taxa, pollen interference periods and the way sensitive patients were affected were evaluated.     

崖柏与侧柏光合特性和叶绿素荧光参数的比较研究

以盆栽的中国特有濒危植物崖柏及其近缘广布种侧柏幼苗为材料,测定了二者的光照和二氧化碳响应特征参数、光合作用气体交换参数和叶绿素荧光参数,比较分析两者间差异并探讨崖柏异地保存的可行性。结果显示:(1)在光响应参数方面,崖柏和侧柏的表观量子效率分别为0.039和0.027 mol.mol-1,但二者差异不显著;崖柏的光补偿点(81.04μmol.m-2.s-1)显著高于侧柏(59.72μmol.m-2.s-1),但二者的最大净光合速率(Pmax)、光饱和点(LSP)和暗呼吸速率(Rd)均无显著差异;崖柏的CO2补偿点(129.17μmol.mol-1)显著高于侧柏(95.86μmol.mol-1),而光呼吸速率则崖柏略高于侧柏,但二者的羧化效率相当。(2)气体交换参数方面,崖柏的叶片气孔导度和蒸腾速率均低于侧柏,而瞬时水分利用效率和气孔限制值则略高于侧柏;随着光照强度增加,崖柏和侧柏的净光合速率和胞间CO2浓度增加,而气孔限制值则降低。(3)2个树种的叶绿素荧光参数,如初始荧光、最大荧光、可变荧光、光系统Ⅱ原初光能转换效率、光系统Ⅱ实际光化学量子效率、非光化学猝灭等均无显著差异,但崖柏光化学猝灭系数(0.218)显著低于侧柏(0.322)。研究表明,崖柏与侧柏在光合特性和叶绿素荧光参数方面具有较大的相似性,也表明崖柏在生长季对北迁环境具有较强的适应性。     

Quantitative dynamics of Ambrosia pollen grains in Bulgaria

The aerobiological study of the Ambrosia pollen in Sofia, Bulgaria began in 1991. The quantitative dynamics of Ambrosia pollen grains during the last seven years was determined by Chebishev's method of parabolic interpolation with orthogonal polynoms. Thesensitization to ragweed pollen was investigated in random groups of patients with clinical manifestation of hay fever.This investigation proves the previouslyobserved tendency of an increase in thespreading of Ambrosia pollen in Bulgaria.     

Loop-mediated isothermal amplification of single pollen grains

The polymerase chain reaction(PCR) has been a reliable and fruitful method for many applications in ecology.Nevertheless, unavoidable technical and instrumental requirements of PCR have limited its widespread application in field situations. The recent development of isothermal DNA amplification methods provides an alternative to PCR, which circumvents key limitations of PCR for direct amplification in the field. Being able to analyze DNA in the pollen cloud of an ecosystem would provide very useful ecological information, yet would require a field-enabled, high-throughput method for this potential to be realized. Here, we demonstrate the applicability of the loop-mediated DNA amplification method(LAMP), an isothermal DNA amplification technique, to be used in pollen analysis. We demonstrate that LAMP can provide a reliable method to identify species from the pollen cloud, and that it can amplify successfully with sensitivity down to single pollen grains, thus opening the possibility of field-based, high-throughput analysis.     

Various methods to determine air pollutants on pollen grains

Birch pollen (Betula sp.) was treated with polluted air and the inorganic components of the pollen surface were analysed by different methods. By EDAX some particles were found to be composed of e.g., Si and S, or Al, Ca and Fe. The SIMS method indicated P, K, Si, Ca, Mg, Al, Na, Rb, Ba, Zn, Sr and B. ESCA seems to be more suitable for analysis of organic compounds, and only C, O, Si, and N could be detected.     

Storage of pollen grains of Crotalaria retusa in oils

Summary Attempts were made to store pollen grains of Crotalaria retusa L. in a mineral oil (paraffin oil) and two vegetable oils (soybean oil and olive oil). Under laboratory conditions pollen grains not stored in oil lost in vitro germinability within 15–30 days, while those stored in oils maintained some degree of germinability even after 60 days. Pollen samples stored in oils at –20° C did not show any decline in germinability or pollen tube vigour even after 6 months of storage. The results amply demonstrate the feasibility of using oils for short- and long-term pollen storage.     

Viral particles in developing pollen grains of Olea europaea

Double-walled tubules containing rows of isodiametric virus particles were observed in developing pollen grains of Olea europaea L. cultivar Correggiolo. Sometimes the tubules are contained in another double-walled tubular structure or in a tubular endoplasmic reticulum cistern. The viruses are present in the cytoplasm from the microspore mother cell stage up to the microspore stage but just before the first haploid mitosis they are to be found only in the pores, inside the evaginations formed by the plasmalemma. During the last phase of pollen grain development, after the germinative pores are completed, the viruses disappear.Abbreviations ER endoplasmic reticulum     

Fine structure of sperm cells in pollen grains ofBeta

Summary The structure of sperm cells in mature trinucleate pollen grains ofBeta vulgaris L. was studied with the electron microscope. The ellipsoidal sperm cell nuclei and cytoplasm are products of mitosis and cytokinesis of the ellipsoidal generative cell. Each sperm cell is separated from the vegetative cytoplasm by two contiguous membranes which enclose its cytoplasm and nucleus. Microtubules present in the sperm cell cytoplasm may be responsible for sperm cell motility.Approved as Journal paper Nr. 846, Utah Agricultural Experiment Station, Logan, Utah.