T HE PRESENT investigation was carried out to study the effect
of x-ray, EA and DES, and the combinations between them on
spectrum of chlorophyll mutations induced in M2 and M3, on two
varieties of Vicia faba namely Giza 1 and Giza 2. Air dried seeds of
each of the two varieties were -irradiated with doses of 0.00, 3, 6, 9
and 12 kr, or treàted with EA in concentrations: 0.05, 0.15, 0.25 and
0.5%, or DES 0.015, 0.020, 0.025 and 0.030M selutions. For combin
ed treatment of radiation and chemicals some seeds of each variety
were treated by 6 kr of -rays followed by DES 0.020 or 0.025 M or
with -ray 9 krfollowed by EA 0.25 or 0.50%.
Mj, M2 and M3 generations were grown through the three successive
seasons (1973-74, 1974-75 and 1975-76).
It was found that the spectrum of chloropyll mutations was affected
by different doses and different mutagens. Thus, in case of X-rays,
albina type decreased by increasing dose from 3 kr to 9 kr, while xantha
and viridis types increased by increasing it in the same range. In case of
EA, the viridis type increased by increasing the concentration from
0.05 to 0.50%, while the two other types, albina and xantha did not
show any dijmnite trend.
Spectrum of chlorophyll mutations was affected by djfferent
mutagens. Thus, after EA the most frequent type was viridis, followed
by xantha type, while in all other treatments the xantha type was the
highest one followed by albina.
No varietal differences in spectrum of chlorophyll mutations were
observed between the two varieties Giza 1 and Giza 2.
Irradiation produces mutation spectra and mutation frequency which are dif
ferent from those induced by chemical mutagens (Favret 1960 and 1963,
Bremer-Renders 1964, Monti 1968, and Desai 1969, Marki and Viann 1970,
Rumulu 1970, Hussein and Abdalla 1974, and Hussein et al. 1974).
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