The behaviour of queen honeybees and their attendants

Abstract. The behaviour of queen and worker honeybees (Apis mellifera L.) was observed using small colonies in observation hives. Workers paid more attention to queens which had been mated for 2 months or more than to those which were newly mated; virgin queens received least attention. Queens received most attention when they were stationary and least when they were walking over the comb; virgin queens were most active. Queen cells had as many attendants as virgin queens and queen larvae were inspected almost continuously. The queen pheromone component 9–oxo-trans-2–decenoic acid stimulated 'court' behaviour when presented on small polyethylene blocks, but workers responded aggressively to complete extracts of queens' heads. Both the heads and abdomens of mated queens received much attention from court workers but the abdomens were palpated by more workers for longer and were licked much more. The queens' thoraces were least attended. Abdominal tergites posterior to tergite glands were licked for longer than those anterior to the glands. Only worker bees very near to the queen reacted to her and joined her 'court'.
No evidence was found of a diel periodicity in the behaviour of a queen or her 'court'. During the winter the queen's court was smaller than in summer and she walked less and laid fewer eggs. When colonies were fed with sucrose syrup in winter, their queens laid more eggs and workers reared more brood but there was no change in the attention received by the queens.
The implications of these findings for the secretion and distribution of queen pheromones are discussed.     

Behavioral analysis of the choice of oviposition site by single females ofDrosophila Melanogaster (Diptera: Drosophilidae)

The oviposition behavior of single females of Drosophila melanogasterwas studied in population cages over 24 h. Each female shows a different behavior, but they can be arbitrarily separated into those which concentrate their egg laying in only one tube and those which spread it over more than two tubes. A comparison is made between females extracted from the Valdivian population and flies from lines selected for high and low aggregation. When one-tube females were grouped and compared with more-than-one-tube females, the aggregation indices between these groups were significantly different.     

4',6-Dichloroflavan (BW683C): Enantiomeric separation by hplc/dad and antirhinovirus activity

Racemic 4',6-dichloroflavan (BW683C), a highly effective inhibitor of rhinovirus serotype 1B in vitro, was resolved by high-performance liquid chromatography on a chiral stationary phase. The enantiomers were separately collected and circular dichroism curves were obtained, in order to determine the absolute configuration of the two enantiomers. The activity of the isomers was studied on human rhinovirus serotype 1B multiplication in HeLa cell cultures, by means of the plaque reduction assay. Both enantiomers were potent inhibitors of virus replication; by comparing the IC₅₀ values, the S form was 3.5 times more effective than the R form.     

Cytogeographical study of four aneuploids ofCarex oxyandra Kudo in Japan

Chromosome numbers were determined for 342 clones ofCarex oxyandra collected from 35 localities in Hokkaido, Honshu, Shikoku and Kyushu, Japan. Four intraspecific aneuploids, 2n=18, 20, 24 and 26, were found. In meiotic division, only bivalent chromosomes were observed in all clones at metaphases I and II, suggesting that the aneuploids are established gamodemes. In the mitotic metaphase chromosomes, trimodal variation in chromosome length was observed. The 2n=26 clones found on Mt. Hiko had two particularly small chromosomes. The cytodemes with higher number of chromosomes are distributed in more southern areas of Japan.Carex oxyandra, therefore, accompanied with chromosome fragmentations, might spread the geographical distribution to the southern parts. The morphological characters of leaves, spikes, scales, perigynia and nuts were similar among the four cytodemes, except for the small leaves on plants from Yaku Island.     

Distribution and immunolocalization of stachyose synthase in Cucumis melo L.

Indirect evidence for the site of stachyose biosynthesis has been provided by determining the occurrence and distribution of stachyose, raffinose and galactinol, the donor of the galactosyl moiety for stachyose synthesis, in Cucumis melo L. cv. Ranjadew. Studies of enzyme activities for the synthesis of these sugars and their distribution in different plant organs and isolates has led to the conclusion that stachyose is synthesized mainly in mature leaves and seeds. Nevertheless, stachyose-synthase activity varied with leaf age, the developmental stage of a plant, the growing season and the plant cultivar used. No stachyose or stachyose-synthase activity could be detected in isolated mesophyll protoplasts and chloroplasts, whereas both were found in a minor-vein-enriched fraction isolated from mature leaves. The conclusion that stachyose biosynthesis is associated with minor veins was confirmed by immunolocalization of the enzyme. Positive specific immunoreactivity of stachyose synthase with polyclonal anti-stachyose-synthase antibodies, labeled with protein A-gold, was detected in intermediary cells of leaf minor veins. The implication of this local synthesis of the main transport sugar for phloem loading in mature leaves of Cucumis melo is discussed.Abbreviation RUBPCase ribulose-1,5-bisphosphate carboxylase This work was supported by Deutsche Forschungsgemeinschaft. The excellent assistance of Ms. B. Müller in preparing the samples for electron microscopy is gratefully acknowledged. The authors thank Professor H.J. Schneider-Poetsch for anti-RuBPCase antibodies.     

Complementarity of genes for resistance to greenbug [Schizaphis graminum (Rondani)], biotype E,in sorghum [Sorghum bicolor (L.) Moench]

Summary Gene complementarity among various sources of resistance to greenbug biotype E was assessed. Analysis of the F₂ generation of crosses between susceptible and resistant parents (mating 1) and among sources of resistance (mating 2) suggested that resistance in sorghum to greenbug biotype E was complexly inherited and, to some extent, dependent on the nature of both the resistant and susceptible parents. Positive transgressive segregation in the F₂ generations of both matings was found to be due to effective plus factors, contributed by both parents in a cross, which complemented each other. The number of plus factors ranged from one to two in the susceptible parents and from two to five in the resistant parents of mating 1, and from one to five in the parents of mating 2. The consistently significant reciprocal effects shown by Sarvasi and PI264453 indicated that these sources had major factors for resistance in their cytoplasms, which were expressed in all their crosses. The results from this study indicated that the sources of resistance complemented each other to give increased number of F₂ segregates with increased resistance. Thus, it should be possible to increase and diversify resistance of sorghum to greenbug biotype E by accumulating different, effective plus factors from various sources through recurrent selection.Contribution No. 90-106-J from the Kansas Agricultural Experiment Station, Kansas State University, Manhattan, KS 66506, USA     

Unfolding domains of recombinant fusion alpha alpha-tropomyosin.

The thermal unfolding of the coiled-coil alpha-helix of recombinant alpha alpha-tropomyosin from rat striated muscle containing an additional 80-residue peptide of influenza virus NS1 protein at the N-terminus (fusion-tropomyosin) was studied with circular dichroism and fluorescence techniques. Fusion-tropomyosin unfolded in four cooperative transitions: (1) a pretransition starting at 35 degrees C involving the middle of the molecule; (2) a major transition at 46 degrees C involving no more than 36% of the helix from the C-terminus; (3) a major transition at 56 degrees C involving about 46% of the helix from the N-terminus; and (4) a transition from the nonhelical fusion domain at about 70 degrees C. Rabbit skeletal muscle tropomyosin, which lacks the fusion peptide but has the same tropomyosin sequence, does not exhibit the 56 degrees C or 70 degrees C transition. The very stable fusion unfolding domain of fusion-tropomyosin, which appears in electron micrographs as a globular structural domain at one end of the tropomyosin rod, acts as a cross-link to stabilize the adjacent N-terminal domain. The least stable middle of the molecule, when unfolded, acts as a boundary to allow the independent unfolding of the C-terminal domain at 46 degrees C from the stabilized N-terminal unfolding domain at 56 degrees C. Thus, strong localized interchain interactions in coiled-coil molecules can increase the stability of neighboring domains.     

室温下有取向紫膜薄层中菌紫质的光静态

在室温条件下有取向PM薄层中的RR分子受光照可以建立多种PSS,这些PSS的建立与湿度和光照所采用的波长等因素有关。不同的PSS有不同的VCD。它们可以在设计制作分子器件时考虑使用。