Report of the Council of the Association of Applied Biologists for the year 1968

Bock (1963) showed that in the years 1956-60 early season sprays achieved good control of coffee berry disease (CBD) in East Rift areas of Kenya. In recent years, however, this spray programme has given erratic and often very poor results. In field experiments in 1966 yields of main (late) crop were increased from 151 to 652 kg/ha by early season sprays but in 1967 practically no control of the disease was achieved. Of the fungicides examined captafol was superior to copper; ‘Tuzet’, the best antisporulant, gave the poorest control. Analysis of the data indicates that this large seasonal variation depends on the very different inter-relationships between rainfall, cropping pattern and timing of sprays which obtained in the 2 years. The hypothesis that early-season sprays achieve control of CBD mainly by reducing the sporulating capacity of the maturing bark is questioned. The view is put forward that the protectant action of these sprays has been underestimated.     

Membrane-binding sites for acyl carrier protein in Escherichia coli

We report that membrane vesicles of Escherichia coli contain protein-binding sites for acyl carrier protein. Scatchard analysis of the binding indicates a dissociation constant around 0.35 micrometers and a maximum number of protein-binding sites around 50 pmol per mg of membrane protein. Binding is on the inner membrane while the outer membrane is devoid of binding sites. These results are consistent with the fact that some acyl carrier protein-dependent enzymes implicated in phospholipid- and membrane-derived oligosaccharide biosynthesis are localized in the cytoplasmic membrane.     

The system of grasses (Poaceae) and their evolution

Originally published in Russian as number 37 of Komarov Readings, 1987. Translated by Victoria V. Michaelova, Brigham Young University, Provo, Utah 84602. Translation edited by Arthur Cronquist, New York Botanical Garden, New York, and approved by the author. A few additions have been made to account for very recent literature.     

C-src locus determines increased rate of Na+,K+-cotransport and increased calcium content in erythrocytes of (SHR x WKY) F2 hybrids

26 male F2 hybrids between spontaneously hypertensive (SHR) and normotensive control (WKY) rats (SHRxWKY)F2 were segregated according to their c-src genotype into SS and WW homozygous groups, corresponding to SHR or WKY and WS heterozygous group. Na, K cotransport in erythrocytes in the WW group was equal to that of WKY and differs significantly from that of WS and SS groups (the rate of Na, K cotransport in latter groups was close to that of SHR). Ca content of RBC in WW group was equal to that of WKY, lower than that of WS and SS groups which in turn was significantly lower than in SHR, indicating polygenic control of the trait. Authors conclude that the c-src locus itself or some other loci inherited in conjunction with c-src determines both the increase of Na, K cotransport and calcium content in erythrocytes of SHR.     

Effect of opiate receptor agonists and antagonists on maternal aggression in rats

The behavioral effects of opiate agonists and antagonists were studied on the female aggression model. Mu-agonist buprenorphine more selectively decreased maternal aggression than kappa-agonist tifluadom. Kappa-agonists (bremazocine, tifluadom) increased passive defence in lactating female rats. Ethopharmacological data shows predominant involvement of brain mu-opiate receptor system in the integrative processes of maternal behavior and maternal aggression in particular.     

Mathematical model of autoimmunity]

A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases.     

a-c electrical properties of bipolar membranes: Experiments and a model

Summary The a-c electrical properties of bipolar membranes separating equal strength solutions of the same uni-univalent electrolyte are analyzed for the case where both ions have equal mobilities. Two membrane models are treated. In one, the fixed-charge density is assumed to be constant throughout the membrane. In the other, the membrane is regarded as comprising an array of pores separated by walls through which the fixed charge is spread uniformly. Experimental results are reported for the a-c electrical properties of a bipolar membrane prepared from a single polyolephine sheet and immersed in KCl solutions of various concentrations. It is found that the data can be interpreted using the pore model.