Mating behaviour in Tetraneura nigriabdominalis Sasaki (=akinire Sasaki) (Hemiptera,Pemphiginae)

Summary

The sex-ratio and behavioural mating peculiarities of Tetraneura nigriabdominalis have been investigated. A morphological study by SEM revealed the developmental stages of sex-attractant pheromone glands on the hind tibiae of females, the morphology of the chemiosensilla on the male antennae, and peculiar microsculptures on abdominal stemites which may be interpreted as an anchorage system favouring copulation.     

DNA Synthesis in Storage Organs of Germinating Seeds: An Autoradiographic Analysis

Storage organs of different germinating seeds were tested forDNA synthesis, which, apart from the normal replication precedingcell division, may also be involved in some regulatory processas suggested by a previous work. Both persistent cotyledons,programmed to grow into green, leaf-like organs (cotyledonsof lettuce, radish and Haplopappus gracilis), and storage organswhich senesce and die after depletion of reserves and wheregrowth and greening are only slight or non-existent (cotyledonsof garden pea, cowpea, soybean, aleurone layers of barley andendosperm of castor bean), were tested. The results showed that widely variable patterns of behaviourcan occur, making it difficult to establish a possible and generallyvalid explanation of nuclear DNA synthesis in storage organsduring germination. Possible interpretations are discussed. Key words: DNA synthesis, Storage organs, Seed germination