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The "sexually deceptive" orchid Chiloglottis trapeziformis attracts males of its pollinator species, the thynnine wasp Neozeleboria cryptoides, by emitting a unique volatile compound, 2-ethyl-5-propylcyclohexan-1,3-dione, which is also produced by female wasps as a male-attracting sex pheromone.
Clones with 24 or 25 chromosomes were obtained by pollinating an Andean cultivated tetraploid potato (Solanum tuberosum subsp. andigena clone 94H94, 2n = 4x = 48) with the Solanum phureja haploid-inducer clone 1.22. Their genetic composition was analyzed in an RAPD assay using 135 decamer primers and in an RFLP assay using 45 single-copy DNA probes. In total, 22 RAPD and 20 RFLP markers were found to be specific to S. phureja. None of these markers were found in the 24- and 25-chromosome clones. RFLP genotypes for the 45 RFLP loci were further determined for each clone. Genotypes of the 24-chromosome clones were characterized using two alleles randomly selected from four alleles of the parental tetraploid clone for almost all RFLP loci. Five 25-chromosome clones had extra alleles for all of the RFLP loci of chromosomes 4, 8, 10, 11, and 12, respectively, suggesting primary trisomy for one of these chromosomes. Clones with genotypes showing double reduction were also identified. Therefore, the obtained clones likely originated from random samples of female gametes, and hence are euhaploids or aneuhaploids of S. tuberosum subsp. andigena, strongly supporting parthenogenesis to be a primary mechanism for haploid induction in potato.
The production of antimicrobial compounds by fungi associated with Clusia spp. pollinating bees (Trigona sp., Trigonini) was investigated in order to approach natural mechanisms of microbial density control within nest environment. By using a bioassay-guided approach based on bioautography and minimal inhibitory concentration (MIC), known alpha,beta-dehydrocurvularin and curvularin were isolated from Curvularia eragrostidis (CCT 5634) and Curvularia pallescens (CCT 5654), and known cochlioquinone A and isocochlioquinone A were isolated from Drechslera dematioidea (CCT 5631).
We studied flight distance and directionality of bee pollinators on the tropical shrub weed Triumfetta semitriloba Jacq. (Tiliaceae), addressing (1) within- and between-plant movement pattern; (2) distances flown between plants; (3) flight directionality. Flowering plants were distributed in well-delimited clumps, in each of two pasture areas (A1 and A2) and one area of forest gap (A3), in Viçosa, southeastern Brazil. Five solitary bee species, Augochlorella michaelis, Augochloropsis cupreola, Pseudocentron paulistana, Ceratinula sp., Melissodes sexcincta, and two social bee, Plebeia droryana, P. cf. nigriceps were observed. All species moved mainly to the nearest flower on the same individual plant and, in between-plant movements, to the first or second nearest neighbor. All species moved non-randomly, presenting a flight directionality in departures (maintenance of flight direction), but with a high frequency of turn angles. It is suggested that this foraging behavior pattern occurred because of the resource quantity and quality (pollen or nectar), and environmental characteristics such as flower density and resource distribution.
Here, we evaluate the potential of the bumble bee Bombus impatiens Cresson, obtained from commercial colonies, as a pollen vector for lowbush blueberry, Vaccinium augustifolium Aiton. We wanted to gain insight into the relationships between pollination by introduced bumble bees, the categories of seeds produced, and the weight and the maturity of the blueberries. The effect of B. impatiens foraging in blueberry stands was measured quantitatively through fruit set and seed set analysis. We created a density gradient of B. impatiens by clustering 72 small hives at the southern extremity of blueberry fields located in Girardville (49 degrees 00' N, 72 degrees 33' W), Quebec, Canada. Observers recorded plant and insect data in 52 plots of 1 by 10 m, distributed at distances ranging from 25 to 1,500 m from the hives. From these data, we evaluated the fruit set rate, the weight and maturity of the berries, and the number of seed structures per berry, including true seeds of large, medium, and small size, pseudo-seeds, and ovules. Positive correlations were found between the density of B. impatiens and fruit set as well as the number of large seeds per berry. Large seeds influenced the weight and maturity of berries. B. impatiens acted as a "near-nest central forager" and increased fruit set and seed production up to 100 and 150 m respectively, from the hives.
Within the framework of the decrees taken on the departments of Isère and Rhone concerning the protection of the population with respect to ambrosia, the object of this study is to relate the analysis of the daily pollen counts in the of air along the Lyon-Grenoble axis. With this intention, three sensors of the type HIRST were positioned according to standards of the European networks in Lyon-Gerland, Bourgoin-Jallieu and Grenoble. The results presented show the curves of the daily pollen counts on the three sites and by indicating the allergic thresholds of risks associated defined by the RNSA. The number of days with high risk, for each of the three sites, can thus be compared. Experiment must be prolonged to follow, these comparative results and moreover, possible effectiveness of the obligations of pulling up of the plant on atmospheric pollination.
The available in literature information as for results of genetic analysis of several self-pollinating cereal species involving the use of plant lines with alien genetic material as the object of analysis is summarized. The restrictions caused by specificity of the investigated material as for the possible explanation of the obtained results are emphasized. Several suggestions concerning the preliminary study of introgressive plant lines before their including into experimental programs on genetic analysis are made.
Theoretical basis and an algorithm of calculations for frequencies of genes and genotypes in the population of species with obligate cross-pollination under assessment for the character of polymorphic genetic basis are proposed. Use of four rye populations and the F1 and F2 from their crossings allows to determine genetic control of beta-amylase spectrum through identification of two genes, establishment of the allele number in each gene, and showing the linkage between beta-Amy-1 and the gene for self-incompatibility S2.
Basophils from peripheral blood of 22 pollinic patients were isolated and were cultured in the presence of different concentrations of ketotifen. We studied the effect of this drug on the specific histamine release (Technicon autoanalyzer) and the levels of intracellular cAMP during days 1, 6 and 12 of culture period. We observed that ketotifen induced an inhibition of specific histamine release throughout the culture days, but was greater on the 12th day. The cAMP levels likewise increased during the period of culture in the presence of ketotifen.
A comparative study of the carbohydrates and protein of five maize cultivars at 30 days after pollination (DAP) showed a higher protein content for the Supersweet variety, and better protein quality for the Maya Opaque-2, Nutrimaiz, the Supersweet, and the Hybrid L90 x L41, when compared to the Maya Normal. The lipid content also proved to be higher in the four genetically-modified cultivars in relation to the Maya Normal. In contrast, the Maya Normal and the Opaque-2 were higher in starch content, lower in total and reducing soluble sugars, and exhibited only very small amounts (approximately equal to 1%) of phytoglycogen, a water-soluble polysaccharide. Nutrimaiz and the Hybrid L90 x L41 had approximately half the starch of the Maya Normal cultivar, but presented an appreciable content of phytoglycogen (23-26%), which is typical for sugary maize mutants, and a higher amount of soluble sugars, mainly sucrose, in relation to Maya Normal. The Supersweet had about half the starch content and a very high (approximately equal to 24%) amount of soluble sugars, mainly sucrose, in relation to the Maya Normal cultivar. The Supersweet also had a negligible amount of phytoglycogen. Nutrimaiz and the Hybrid L90 x L41 showed a much higher proportion of grain in the ears and, as a consequence, a higher yield of dry solids at 30 DAP, when compared with the Maya Normal cultivar.
Characterization of starch was comparatively studied in five maize cultivars, i.e., Maya Normal, Nutrimaiz, two hybrids (L90 x L78, L90 x L41) and Supersweet (SRR "Duro"), 30 days after pollination (30 DAP). Amylose content was found to be higher in the Maya Normal starch (31.3%) and lower (23 to 27%) in the genetically-modified cultivars. The absolute density of the isolated starches did not show significant differences among cultivars. Solubility and swelling studies suggested the presence of more homogenous forces maintaining the granular matrix on the starch from Maya Normal in relation to the other maize cultivars. The starch from the genetically-modified cultivars had a reduced solubility in dimethylsulfoxide and lower values for the gelatinization temperature range, in comparison to the Maya Normal. Information from the Brabender amylogram indicated greater resistance of the gelatinized maize starches to granule breakdown by mechanical stirring, in the new genotypes, resembling those starches modified by cross-linking.
In warmer regions of North America many newly introduced plants are cultivated widely and others are becoming aggresive naturalized weeds. A large number are insect-pollinated and shed considerable quantities of airborne pollen. Levels of allergenicity based on skin test data, numbers of patients having immediate hypersensitivity and localities where airborne pollen grains have been identified are presented for each genus of entomophilous plants considered incitants of pollinosis. Among the most relevant are Acacia, Brassica, Citrus, Ligustrum, Olea and Schinus.
In order to study the possible variations of CD4 and CD8 antigens in pollinic patients, we have studied 25 individuals (11 rhinoconjunctivitis and 14 rhinoconjunctivitis-asthma) before (T0), in the middle (T1) and after the spring (T2). The number of receptors per cell of CD4 start from values in T0, decrease in T1 and increase at the end of the spring (p < 0.00001), which could represent a mechanism to limit the clonal response to an antigen. An increase in the CD4/CD8 bright ratio could be indicate a higher helper mechanism in T1 with respect to T0 and T2 (p < 0.01). The opposite meaning is to given to the increase of CD8bright receptors in the asthmatic patients, and not only in those who suffer only from a rhinopathy (the only difference between the two groups of patients) during T2 over the T1 (p < 0.00001). The greater number of lymphocytes CD8 dim + during T1 with respect to T2 (p < 0.009) and the increase in the number of receptors of such cells during T1 with respect to T2 (p < 0.00001) suggests a possible intervention of these cells in the regulation of the response of the B and T lymphocytes. Of the two soluble factors CD4 (sCD4) and CD8 (sCD8), only the sCD4 increases during T1 (p < 0.0001) in an inverse manner as occurs with CD4 cell receptors, while the sCD8 remains unchanged during the three periods.(ABSTRACT TRUNCATED AT 250 WORDS)
The flower scents of 11 bat-pollinated plant species have been investigated using the 'closed-loop-stripping'-adsorption technique. GC and GC/MS analyses of the headspace samples resulted in the identification of 49 compounds, comprising amongst others sulphur compounds, terpenoids and aliphatic compounds.
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