A comparative study of specific chromatic adaptation of the wildtype and trp mutant of Drosophila melanogaster

The trp mutant of Drosophila melanogaster was re-examined and compared with the wildtype using monochromatic blue and orange light to manipulate the bi-stable visual pigment states in the peripheral retinula cells R1-6 of white-eyed flies. Recovery of sensitivity by application of orange light either during or after blue-adaptation is different in w;trp flies from that in bw;cn flies and does not proceed as predicted from the trp genotype. Blue-adaptation by isolating the activity of the central retinula cells confirms that the trp lesion affects these receptors also.