Daskaloff, Hr., M. Konstantinova, K. Moinova Inheritance of soluble pectin content in tomato fruits used for
processing.
In 1977 and 1978 the soluble pectin content was studied in tomato fruits of a 7 x 7 1/2 combination diallel
cross, the parent cultivars and lines of which were suitable for processing. Fruits of P1, P2 and F1 were analyzed.
Results obtained show that soluble pectin content, which is determined by genes directly controlling the
ability to synthesize, is a hereditary character. In lines BS-2 and I6 a negative correlation between the Wr + Vr and
soluble pectin content exists, therefore, the high values for that character are evidently determined by dominant
genes. In the remaining parent cultivars no correlation is observed, a fact indicating the presence of dominant genes
which act in opposite directions (Table 1).
Figure 1 indicates that the inheritance of soluble pectin content in F1 is mainly overdominant. The d/a ratio of
dominant to additive parameters is considerably larger than 1 but with a negative sign, which substantiates the
assumption of negative heterosis. This interesting fact requires to be further explained in connection with the
economic value of the parental cultivars and lines used in the diallel cross, which are bred in view of being used for
industrial processing.
Farrell, M. and C. M. Rick Mutations induced by EMS treatment of cv. VFNT Cherry.
Seeds of Lycopersicon esculentum cv. VFNT Cherry (synthesized by Dr. Paul Smith at U.C. Davis) were
soaked in a 1.6% EMS solution for 24 hours, rinsed in circulating tap water for 4 hours, sown in wooden nursery
flats containing sterilized soil, and transplanted to the field in rows, separating groups according to seedling vigor.
Seeds from fruits of these M1 plants were sown by directly squeezing seeds from the fruits into flats without
preliminary extraction. A total of 25,771 M2 seedlings comprising 621 progenies were scored in the greenhouse after
true leaves had formed. Notes were taken on all variants, and the classifications and distribution frequencies listed
in Table I were derived from the recurring variant phenotypes. These results demonstrate the efficiency of this
alkylating agent in inducing a high mutation rate (136%) in seedlings. The table also shows that a substantial portion
were chlorophyll mutations - 42% of all progenies, or almost one-third of the total mutations scored. Further
experiments utilizing treated pollen are being carried out to determine the nature of control of these mutations.
A test was made to find out if a correlation to seedling vigor (measured by earliness and seedling size)
existed. The broad range (Table II) of mutation rates does not indicate that such a relationship exists.
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