“…L INDSTEN et al (1976) (MI NK et al, 1969 ;K NE S EK & MINK, 1970) and Switzerland (P EL E T , 1980) and 55 % infected seed in Czechoslovakia (M USIL , 1970 (THAKUR et al, 1984). Above BAGGET, 1970 ;BOS, 1970 ;HAGEDORN, 1974 ;HAMPTON & MINK, 1975 ; § ZIMMER & ALI- KHAN, 1976 ; KRAFT & HAMPTON, 1980 ;PELET, 1980 ;HAMPTON, 1984) Japan (I N O UYE , 1967) and so also the differences in ultrastructural cytology (H AMPTON et al, 1973), initially suggested the existence of strains in PSbMV. However, discrepancies in reported particle lengths for PSbMV were partially resolved by H AMPTON et al (1974) (Bos, 1970) Recently three more pathotypes of PSbMV (namely P-1 and P-4 from pea, and L-1 from lentil) have been characterized on the basis of their infection of pea genotypes (ALCONERO et al, 1986 (1973).…”