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Notes: Straw burning destroyed many Alopecurus myosuroides(blackgrass)seeds lying on the soil surface and, compared with straw baling, resulted in a smaller weed infestation in a subsequent direct-drilled winter wheat crop. The larger the amount of straw burnt, the higher the temperature reached on the soil surface and consequently the greater the control of the weed. Seeds that were fully imbibed were less susceptible to destruction by heat than were dry seeds. A shallow soil covering protected most seeds although some were stimulated to germinate. After straw burning the soil surface was a better environment for seed germination or seedling development than that under stubble. Differences in seedling numbers between treatments were not always proportional to differences in the numbers of viable seeds in the soil.Quelques effets du brûlage des pailles des céréales sur la viabilité des semences et l'implantation des plantules d'Alopecurus myosuroïdes Huds. et influence sur sa destructionLe brûlage des pailles a détruit de nombreuses semences d'Alopecurus myosuroïdes (vulpin) se trouvant à la surface du sol, ce qui a eu pour effet, par comparaison avec la récolte de la paille, de réduire l'infestation de la mauvaise herbe dans la culture suivante, un blé d'hiver en semis direct. Plus grande est la quantité de paille brûlée plus la température au niveau du sol est élevée et, par suite, meilleure est la destruction de la mauvaise herbe. Les semences qui avaient été complètement imbibées se sont montrées moins susceptibles d'être détruites par la chaleur que les semences sèches. L'existence d'une couche meuble superficielle sur le sol s'est révélée comme un meilleur environnement pour la germination des semences ou le développement des plantules que sous le chaume. Les différences entre le nombre des plantules selon les traitements n'ont pas toujours été proportionnelles aux quantités de semences viables présentes dans lesol.Einige Auswirtcungen des Verbrennens von Getreidestroh auf die Lebensfähigkeit der Samen, das Auflaufen und die Bekämpfung von Alopecurus myosuroides Huds.Das Verbrennen von Stroh zerstörte viele Samen von Alopecurus myosuroides(Ackerfuchsschwanz) die auf der Bodenoberfläche lagen und hatte, im Vergleich zum Ballenpressen, eine geringere Verseuchung in im Direktsaatverfahren nachgebauten Weizen zur Folge. Je grösser die Strohmenge war, desto höher war die Temperatur auf der Bodenotrerfläche und umso besser war die Bekämpfung des Ackerfuchsschwanzes. Samen, die mit Wasser vollgesogen waren, wurden durch die Hitze weniger geschädigt als trockene. Durch eine flache Bodenabdeckung wurden die meisten Samen geschützt, bei einigen wurde aber die Keimung stimuliert. Nach dem Strohverbrennen waren die Bodenverhältnisse für die Keimung und die Entwicklung der Keimlinge günstiger als in der Stoppel. Die Unterschiede in der Keimpflanzenzahl zwischen den Behandlungen waren nicht immer proportional zu den Unterschieden in der Anzahl lebensfähiger Samen im Boden.

Notes: Seed shedding from heads of Alopecurus myosuroides occurred from late June to late August at most locations. Most seeds were shed before winter wheat (Triticum-aestivum L.) was harvested hut at two winter barley (Hordeum sativum L.) sites, only 50% of seed was shed prior to harvest. The viability of seeds shed at the start and end of the shedding period tended to be lower than that at peak shedding time in late July and early August. There were large differences between sites in the viability of the total amount of seed shed. The results of viability tests based on the presence of full caryopses and germination in pots of sterile soil were similar. Assessments of head numbers and head length were significantly correlated with total seed production. Head length, but not head number assessments, were also significantly correlated with viable seed production.

Notes: Summary Viruses were isolated from two of three pools of the tickIxodes uriae collected from a puffin(Fratercula arctica) colony on the Shiant islands. One pool contained an orbivirus whereas evidence of both orbi- and bunyaviruses was found in the second pool. Serological tests showed that the orbiviruses were related to Cape Wrath virus in the Kemerovo serogroup; the bunyavirus appeared to be related to Clo Mor virus of the Sakhalin serogroup. The results indicate that an interchange of viruses may occur within seabird colonies of the north-west of Scotland.

Notes: The metabolic fate of the synthetic prostaglandin cloprostenol (“Estrumate”) in the cow has been studied. Following intramuscular administration of 0.5 mg and 10 mg of [14C]cloprostenol to cows urinary excretion accounted for 58.2% and 56.3% of the dose respectively. Unchanged cloprostenol and its tetranor acid, probably formed by β-oxidation, were the major components identified in urine. The tetranor acid was also present as a glucuronide conjugate. This synthetic prostaglandin analogue is apparently a poor substrate for the enzymes 15-hydroxyprostaglandin dehydrogenase and 13,14-reductase, which are responsible for the rapid metabolic deactivation of endogenous prostaglandins, as no components identified in urine were found to have undergone metabolic attack at the C-15 atom in the cloprostenol molecule.

Notes: Summary Viruses were isolated from 2 tick species collected from the nesting areas of seabirds on Great Saltee Island, Eire. Bunyaviruses of the Uukuniemi serogroup were isolated from hard ticks(Ixodes uriae andI. rothschildi), bunyaviruses of the Hughes serogroup from soft ticks(Ornithodoros maritimus), and orbiviruses of the Kemerovo serogroup fromI. uriae andO. maritimus. The results indicate that the bunyaviruses, but not the orbiviruses, show “tick specificity”. Neutralising activity against members of all 3 serogroups was detected in sera from chicks in the nesting areas; neutralising antibodies were probably maternal.