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[en] The objective of this investigation was to improve certain important characters in wheat through hybridization using irradiated and non-irradiated pollen of triticale and rye. Seeds of first and second backcross (BC1 and BC2) obtained in a previous season from hybridization between (Mizar X Saberbeg) and Saberbeg were sown under the field condition. At flowering, some spikes were backcrossed with Saberbeg or Mizar and then the BC2 and BC3 seeds were collected
[en] Pollens and seeds of Hypoestes and Rhinacanthus collected from different field localities in Taiz and Soqotra Island, Yemen were investigated by using light and scanning electron microscopes. Pollen grains of Hypoestes were prolate in equatorial view, lobate trigonal to lobate circular in polar view whereas those of Rhinacanthus were sub spheroidal and rounded trigonal in polar view. The aperture was tricolporate and exine ornamentation was coarsely reticulate for all species in the two genera. Scanning electron microscopy and morphological observations showed that mature dry seeds of Hypoestes and Rhinacanthus have various sizes and shapes, the surface ornamentations observed were reticulate to cristate, an addition to the tuberculum and papillae. The three Hypoestes species differ in the seed structure which are useful for identification and their high structural diversity provides an important taxonomic value for species differentiation. (author)
[en] This study describes a microtiter double antibody assay for the measurement of specific IgG, which is believed to be identical with blocking antibodies. The precipitates were harvested on glass fiber filters, and the activity from iodinated antigens fixed in the precipitates was used as a measure of the level of the serum blocking antibodies. (author)
[en] The increasing prevalence of asthma in many countries has been related to weather factors and aeroallergen concentrations , but this has not been studied in Kuwait. We evaluated the effect of meteorological factors and the occurrence of aerobiologicals on the number of asthma cases in Kuwait.The number of daily asthma visits to the allergy center and emergency department at Al-Sabha Hospital for 1 year were examined on a monthly basis for correlation with major metereological factors (temperature , relative humidity , rain , wind speed and direction). Spore and pollen counts were collected hourly. Results: A total of 4353 patients received asthma treatment during the year. The highest pollen count was in the month of September with a maximum relative humidity of 47% and no precipitation , but with a high mean temperature of 39.70C. . Pollen counts were higher in the late summer (September) and occurred with a high patient visit to the allergy center. Fungal spore counts were significantly higher in early winter (December). The high fungal spore count seemed related to with high relative humidity and high precipitation with a low mean average temperature of 19.70C. The increase number of patients with bronchial asthma visiting an emergency clinic during December was significantly associated with high aerial counts for fungal spores (P<.03) , and the months of September and October were more significant for pollen.This study indicates that meteorological factors , aeroallergen concentrations and asthma related visits are interrelated. The results may prove useful in the generation of hypotheses and development of designs for more comprehensive , individual-based epidemiological studies (Author).
[en] The common soil arthropod Folsomia candida can survive well when fed only maize pollen and thus may be exposed to insecticidal proteins by ingesting insect-resistant genetically engineered maize pollen containing Bacillus thuringiensis (Bt) proteins when being released into the soil. Laboratory experiments were conducted to assess the potential effects of Cry1Ab/Cry2Aj-producing transgenic Bt maize (Shuangkang 12–5) pollen on F. candida fitness. Survival, development, and the reproduction were not significantly reduced when F. candida fed on Bt maize pollen rather than on non-Bt maize pollen, but these parameters were significantly reduced when F. candida fed on non-Bt maize pollen containing the protease inhibitor E-64 at 75 μg/g pollen. The intrinsic rate of increase (rm) was not significantly reduced when F. candida fed on Bt maize pollen but was significantly reduced when F. candida fed on non-Bt maize pollen containing E−64. The activities of antioxidant-related enzymes in F. candida were not significantly affected when F. candida fed on Bt maize pollen but were significantly increased when F. candida fed on non-Bt pollen containing E−64. The results demonstrate that consumption of Bt maize pollen containing Cry1Ab/Cry2Aj has no lethal or sublethal effects on F. candida. - Highlights: • A validated dietary exposure assay for assessing the effect of GE plant pollen on the springtails. • Cry1Ab/2Aj-containing maize pollen does not negatively affect on the fitness of F. candida. • The antioxidant-related enzyme activities in F. candida were not significantly affected. • Planting cry1Ab/2Aj-expressing maize will pose a negligible risk to the springtails.
[en] Pollen morphology of five genera of the family Acanthaceae, namely Ruellia, Blepharis, Asystasia, Ecbolium and Dicliptera (Acanthaceae) of Yemen has been examined using light and scanning electron microscope. Pollen descriptions were provided with two shapes distinguished, spheroidal and prolate. Most of the pollen grains were tricolporate amd psuedocolpi except those of Blepharis which are colpate. The surface is coarsely reticulate, in addition to the lumina that varies in size
[en] Andromonoecious Jatropha curcas (Jatropha) has male and hermaphrodite flowers in one inflorescence. Jatropha is a potential source for biofuel raw material. The development of this plant has various constraints, such as lower fruit set that causes low seed productivity. The existence of andromonoecious Jatropha with high fruit set provides a great opportunity to overcome the obstacles. Understanding floral biology is a requirement for developing a high fruit set andromonoecious Jatropha. This study was aimed at understanding the flower's characteristics and phenology. The andromonoecious Jatropha flower's characteristics, number and viability of pollen, and phenology were observed and compared to those of monoecious Jatropha. Andromonoecious Jatropha had inflorescence with a dichasial cyme pattern. An inflorescence produced two main branches and several secondary and tertiary branches, where a hermaphrodite flower was found at whose ends. The number of inflorescence branches in andromonoecious Jatropha was higher than that of monoecious Jatropha. The diameter and size of the sepal and stalk in hermaphrodite flowers were found to be larger than those in male and female flowers. The development of andromonoecious Jatropha flowers was divided into 4 phases, namely initiation (0-3 dai = days after initiation), small bud (3-7 dai), large bud (7-20 dai), and flower blooming (20-39 dai) phases. The anthesis and anther dehiscence of hermaphrodite flowers occurred at the same time between 06:00 to 06:59 am, facilitating self-pollination of the hermaphrodite flowers. The average pollen viability during the anthesis phase was 96.26%, and 88.79% of them survived until the next day. (author)
[en] Highlights: • TPMVd but not PSTVd is transmitted horizontally by infected pollen. • Infection of TPMVd in style and ovary is involved in horizontal transmission. • Fertilization is unnecessary for horizontal transmission of TPMVd. For viroids, pollen transmission is an important transmission pathway to progeny seeds and new hosts. In the current study, we found that Tomato planta macho viroid (TPMVd)—but not Potato spindle tuber viroid (PSTVd)—was horizontally transmitted by pollen from petunia plants. Using tissue-printing hybridization to track the changes in viroid distribution after pollination, we noted that TPMVd was present in petunia stigma, styles, and eventually ovaries, whereas PSTVd was detected in the stigma and upper style but not the ovary. These findings suggest that horizontal transmission of viroids depends on the infection of the lower style and ovary during the elongation of pollen tubes after pollination. Additionally, TPMVd was transmitted horizontally, leading to systematic infection, when we used TPMVd-infected petunia pollen to pollinate the flowers of healthy tomato plants. Fertilization typically does not occur after heterologous pollination and thus likely is not required to accomplish horizontal transmission of viroids.
[en] Among the various biological particles, pollen grains and fingal spores stand as the two major factors that can cause asthma and allergic rhinitis. Pollen grains can be released by the domestic plants cultivated in and around as omamentals, on road verges and parklands etc. However. those plants are considered allergenic which are wind pollinated, called anemophilous, and very less attention is paid pollen sensitivity of cultivated plants. The purpose of this publication is to explain the types of flowering plants cultivated in Sindh, their flowering periods and the possibility of their pollen grains to induce IgE mediated hypersensitive reaction in people living in tile selected geographical region. In this survey. we have taken into consideration 60 species of plants that are being cultivated in tile province of Sindh. These species are divided into two major groups: the first group includes allergenic pollen producing species. while the second group included 38 species that are known to be non-allergenic. Our results show that most of the abundantly cultivated plants may be considered as secondary potential allergens and/or occupational or cross-reacting allergens. (author)
[en] The study was undertaken to determine the influence of pollen sources and pollination frequency on fruit drop, yield and quality of date palm cv. 'Dhakki'. Three 'Dhakki' female trees and three different male trees (M-1, M-2 and M-3) were selected for the experiment. On each female tree six spathes were chosen and were pollinated with pollens collected from one of the selected male parent. Out of six, three spathes were pollinated once and other three were pollinated twice (second pollination was done two days after first pollination). Data were collected for physico-chemical characteristics of the fruit including fruit drop, fruit weight, flesh weight, seed weight, total soluble solids (TSS), titratable acidity (TA), TSS: TA ratio, sugars, level of ascorbic acid and total phenols. The results indicated that pollen source significantly affected the fruit drop percentage as minimum fruit drop was observed from the tree pollinated with M-3. Physical properties of the fruit like fruit weight, flesh weight and seed weight were significantly improved with pollination from M-1 compared to other male trees. After harvest chemical quality parameters like TSS and TSS: TA ratio, ascorbic acid contents, and reducing sugars were highest in fruit pollinated with M-3 and M-2 respectively. Whereas lowest level of TA was recorded in fruits pollinated with M-3. Pollen source and number of pollinations did not significantly affect the level of total phenols in the date palm fruit. Total and non-reducing sugars were significantly higher in the fruit pollinated twice. In conclusion, the pollen source had significant impact on the physicochemical properties of date palm cv. 'Dhakki'. The results suggested that best pollen source (male trees) should be selected for their respective female trees to get most desired characteristics. (author)