Alfalfa mosaic virus temperature-sensitive mutants. III. Mutants with a putative defect in cell-to-cell transport.

Forty-five mutants of alfalfa mosaic virus with a temperature-sensitive (ts) replication in tobacco leaf discs were assayed in cowpea protoplasts at 25 and 30 degrees . The extent of replication of 9 mutants at 30 degrees was less than 10% of that at 25 degrees, whereas the replication of 14 mutants was not affected at 30 degrees. Twenty-two mutants showed an intermediate ts behavior.