Cell-mediated immunity in mouse experimental coxsackie A9 virus infection

Using a human A₉ Coxsackievirus strain as antigen and different-aged A₂G inbred mice as receptors an in vitro secondary cell-mediated immune response was noticed, revealed by means of two markers, i.e. leukocyte migration inhibition and T spleen lymphocyte blastogenesis, in the presence of viral antigen.     

Leaf eating insect damage on different poplar clones and sites

As much for the geneticist as for the planter, information on sites, clones, and other factors would be decisive to reduce insect damage on poplars. In this perspective, a study was done in eight field trials in Belgium and in Luxembourg, considering two types of leaf damage on 24 clones from Italy, Belgium and the Netherlands. Damage varied considerably, depending on the clones, sites, species and parental individuals. Clone’s ranks concord on the different sites; site’s ranks are similar for the various clones. Clones with same parents have similar levels of resistance. The two types of damage are not correlated. Hybrids of P. deltoides × nigra show widespread variability; those with genetic material of P. trichocarpa are generally more resistant to caterpillar-like damage. The maximal differences are about 1 to 5 for the clones, and 1 to 10 for the sites. But the most vulnerable clone on the most favourable site was damaged almost 70 times more often than the opposite combination.