Sterilising activity of methoprene and hydroprene inTribolium castaneum (Herbst)

Summary The productivity ofT. castaneum adults, previously reared in flour incorporating either the IGR methoprene or hydroprene, was found to be impaired depending on the concentration of the IGR in the flour, whether or not the individual was morphologically deformed, and its sex.The authors are indebted to Mr P. B. Du Guesclin for technical assistance, and Dr J. Diekman, Zoecon Corporation, California, for supplying the IGRs. This work was financed in part by the Australian Wheat Industry Research Council.     

Hormetic concentrations of azadirachtin and isoesterase profiles inTribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

Electrophoretic pattern of esterases from larvae ofTribolium castaneum fed on a diet which included hormetic concentrations of azadirachtin (viz. 0.001, 0.01 and 0.1 ppm) for 10 d were studied. The results showed a dose-dependent variation in the multiple molecular forms of the esterases. The variations, however, were not limited to the synthesis of new isoforms or the deletion of existing ones; there was also variation in their relative abundance.     

The effect of leafhopper infestation on the respiration of castor bean varieties in relation to their resistance toEmpoasca flavescens (F.) (Homoptera: Jassidae)

Zusammenfassung Die Saugtätigkeit der JassideEmpoasca flavescens (F.) führte zu einer um 44% gesteigerten Respiration von geschädigten, anfälligen Rizinuspflanzen (Ricinus communis L.) im Vergleich zu 11.6% und 3.7% bei Pflanzen einer toleranten und resistenten Sorte. Diese Zunahme war bei der anfälligen Sorte verknüpft mit einer gesteigerten Anhäufung von Rohrzucker, Gesamtstickstoff und Gesamtaminosäuregehalt.

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This study formed part of the Doctoral Thesis submitted to the University of Madras and financial support was given by the Council of Scientific and Industrial Research, Government of India, New Delhi. Grateful appreciation is extended to Prof. A. R.Seshadri, Agricultural College and Research Institute, Coimbatore, India and Prof. R. H.Painter, Kansas State University, Kansas, U.S.A. for their valuable suggestions made during the course of the study.     

Induction of thermosensitivity and salt sensitivity in wheat roots (Triticum aestivum) and the effect of kinetin

Zusammenfassung Die Hitzesensibilisierung von Weizenwurzelmeristemen kann durch Kältebehandlung oder Kinetinzugaben zumindest teilweise rÜckgängig gemacht werden.     

Some factors affect the degradation of (2-chloroethyl) trimethylammonium chloride by wheat plant extracts

Zusammenfassung Extrakte aus Weizenpflanzen enthalten ein System, welches Chlorocholinchlorid zu Cholinchlorid umwandelt. Dieses System wird durch pH, aber nicht durch die Temperatur beeinflusst und hat zwei Komponenten; die erste wird durch ZnCl₂ gefällt, und die andere ist dialysierbar.     

Potentiating the diabetogenic effect of alloxan by N-sulphonyl-N-butylurea (BZ-55)

Zusammenfassung Es wird festgestellt, dass im voraus verabreichtes BZ-55 die diabetogene Wirkung des Alloxans bei Mäusen potenziert.     

Prevention of the formation of mycotoxins in whole wheat bread by citric acid and lactic acid (Mycotoxins in foodstuffs. IX)

Summary Additions of citric acid and lactic acid to whole wheat bread suppress the formation of aflatoxins byAspergillus parasiticus (0.5% citric acid, 0.75% lactic acid) and that of sterigmatocystin byA. versicolor (0.25 and 0.5% respectively).Acknowledgment. I thank Dr.R. Orth (Bundesforschungsanstalt für Ernährung, Karlsruhe, BRD) for the strain ofAspergillus versicolor.     

Haploidy induced by radiations in wheat

Zusammenfassung Bestrahlung von Weizenähren (Triticum aestivum L. Varietät N.P. 809) mit X-Strahlen (5200 r) kurz vor dem Blühen sowie geeignete Behandlung von Topfpflanzen oder Karyopsen der gleichen Pflanze mit P³² oder S³⁵ erzeugen haploide Formen.     

Presence of a protein disulfide isomerase (EC 5.3.4.1) in wheat germ]

The presence of a protein disulfide isomerase (rearrangease) in wheat embryo has been demonstrated by its ability in reactivating randomly cross-linked ribonuclease. This activity requires a dialysable cofactor; after dialysis, the activity is recovered by addition of reduced glutathione. The enzyme can be precipitated by 70% saturation ammonium sulfate.     

The effect of locality,breed and previous tick experience on seasonal changes in the resistance of cattle toBoophilus microplus (Ixodoidea: Ixodidae)

Summary A seasonal cycle in the expression of resistance to the tickBoophilus microplus occurs in cattle in central and southeastern Queensland, Australia. This is due to a seasonal fluctuation in the capacity of cattle to mount an effective immune response against the parasitic tick and is manifest as a waning of the expression of resistance in autumn and early winter which occurs irrespective of breed or the nutritional state of the cattle.     

Prostaglandin A2 (PGA2) increases the coronary vascular resistance in the guinea-pig isolated heart preparation

Summary Prostaglandin A₂ (PGA₂) in concentrations of 1.5·10^–8 to 3·10^–6 M was found to produce concentration-dependent increase in the coronary vascular resistance of the guinea-pig isolated heart without alterations in myocardial contractile force and oxygen consumption.Supported by the Deutsche Forschungsgemeinschaft.     

In vitro cytostatic effect of adenine-arabinoside (Ara-A) and cytosine-arabinoside (Ara-C)

Summary Adenine-arabinoside, a new antiviral drug with questionable bone marrow toxicity, inhibits colony formation by myeloid precursor cells in vitro. Compared to cytosine-arabinoside this cytotoxicity is roughly one third.Supported by grants of the Swiss Cancer League (FOR 101.AK.77.2) and the Swiss Science Foundation (3.3320.74).Acknowledgments. We wish to thank Prof. A. Lévy for support in providing normal bone marrow samples and Miss Beatrice Rubin for skilled technical assistance.