Laboratory assessments of the susceptibility of potato-tuber tissue to blight (Phytophthora infestans)

Laboratory studies of potato tuber resistance to infection by Phytophthora infestans

“…This indicates that tests on whole tubers, also used by Lapwood (1967) and Mooi (1963) are probably a better index of resistance than that obtained from progress of P. infestam through tissue (Lapwood, 1965; Deahl & Gallegly, 1970; Langton, 1972); especially as Davila ( I 964) showed that cultivar differences, apparent when infection occurred through small wounds, were reduced when the wounds were large. The concentration of sporangia used in screening for resistance did not affect the sensitivity of the test in the present work in contrast to that of D a were performed before its importance was appreciated.…”

Breeding potato cultivars with tubers resistant toPhytophthora infestans

“…Such genotypes were also found in segregating potato progenies (Swiezyriski et al, 1997a). A barrier to P. infestans in the outer cortex of the tuber has been reported to be present in several potato cultivars (Toxopeus, 1961;Lapwood, 1965). A barrier to P. infestans in the outer cortex of the tuber has been reported to be present in several potato cultivars (Toxopeus, 1961;Lapwood, 1965).…”

“…However it is difficult to provide a satisfactory infection pressure in the field and repeatable testing conditions (Lapwood, 1965;Ullrich, 1967;Sch6ber, I987;Dorrance & Inglis, 1998;Platt & Tai, 1998). However it is difficult to provide a satisfactory infection pressure in the field and repeatable testing conditions (Lapwood, 1965;Ullrich, 1967;Sch6ber, I987;Dorrance & Inglis, 1998;Platt & Tai, 1998).…”

“…There were several attempts to compare the relative advantage of various laboratory evaluation methods (Lapwood, 1965(Lapwood, , 1967Durska, 1975;Pietkiewicz & Jellis, 1976;Dorrance & Inglis, 1998). The widest acceptance appears to have been found for the evaluation of whole tubers and the evaluation of tuber slices, both modified in various ways.…”

“…They could be undamaged (Wastie et al, 1987(Wastie et al, , 1993 or wounded (Darsow, 1992). If the resistance is evaluated in tuber slices, the widest acceptance has been found for the method of Lapwood (1965) in which tuber slices are inoculated on one side and the effects are evaluated on the other side of the slice. If the resistance is evaluated in tuber slices, the widest acceptance has been found for the method of Lapwood (1965) in which tuber slices are inoculated on one side and the effects are evaluated on the other side of the slice.…”