Pecaut, P., J. Philouze A sha-pat line obtained by
natural mutation.
A mutant line, Montfavet 191, has been
obtained by natural mutation in our breeding
material from a line with normal stamens and
producing non-parthenocarpic fruits. Montfavet 191 possesses the flower characteristic shown by the sha
(short anthers) mutant described by Soressi (TGC 20:59) and reveals an ability to develop
parthenocarpic fruits similar to the pat (parthenocarpic) mutant described by Soressi (TGC 25:22).
Montfavet 191 was crossed with the sha-pat material (stock 2524) provided by Soressi. The F1 hybrid
had flowers with abnormal stamens and developed parthenocarpic fruits. So Montfavet 191 is sha-pat.
We have, however, a few remarks to make:
1. Our obtaining sha and pat mutations simultaneously in the same line is surprising. We were
unsuccessful in obtaining the short anther and parthenocarpic characters in separate lines, as
Soressi was able to do (TGC 25:22).
2. Expression of the short anther character is variable according to genotype and environmental
conditions. For example the stamens of the 2524 stock are shorter than those of Montfavet
191. The stamen length of a sha-pat plant may vary during the flowering period, the stamens
sometimes taking on a quasi normal appearance.
3. Our sha-pat material and Soressi's sha-pat stock 2524 show an important amount of female sterility. It
is very difficult to obtain seeds from both materials either by self-pollination or by pollination
with sha+ pat pollen, even in favorable environmental conditions. However, sha-pat pollen has
normal fertilizing power.
Philouze, J. Percentage of selfing. . .(seep. 13.)
Philouze, J., and B. Maisonneuve Heredity of
the natural ability to set parthenocarpic
fruits in a German line.
Line 75/59 received from Reimann-Philipp
(West Germany) shows a natural ability to set
normal-looking parthenocarpic fruits. We screened
parthenocarpic and non-partheno-
carpic plants in the same manner as in the study of Severianin (TGC 28:12).
The F1 hybrids between 75/59 and two non-parthenocarpic varieties, Moneymaker and
Apedice, were studied. The fruits of the two F1 hybrids were not parthenocarpic. The parthenocarpic
character of 75/59 is therefore recessive.
Allelism tests were made with two different parthenocarpic lines: Montfavet 191 (France)
is sha-pat (TGC 28:12) and Severianin (USSR) is pat-2 (TGC 28:12).
The fruits of the two F1 hybrids 75/59 x Severianin and 75/59 x Montfavet 191 were not
parthenocarpic, so neither the pat allele nor the pat-2 allele is responsible for parthenocarpy in 75/59.
At present we are studying offspring from the Moneymaker x 75/59 cross to determine how
many loci are responsible for parthenocarpy in 75/59.
In favorable environmental conditions female fertility in 75/59 is quite normal, as in the case
of Severianin, and its pollen has normal fertilizing power.
Philouze, J., and B. Maisonneuve Heredity of the
natural ability to set parthenocarpic
fruits in the soviet variety Severianin.
The soviet variety Severianin was bred by N.
Solovjova at the Gribovskja Experimental
Vegetable Selection Station near Moscow. This
variety is remarkable for its natural ability to
set normal-looking parthenocarpic
fruits. In our study we screened parthenocarpic and non-parthenocarpic plants by emasculating flowers
before the pollen was mature and by omitting pollination. Under these conditions the fruits of the
parthenocarpic plants developed, whereas no fruit was borne by the nonparthenocarpic plants.
We studied the F1 hybrids between Severianin and two non-parthenocarpic varieties,
Moneymaker and Apedice (one of our breeding lines). The fruits of the two F1 hybrids were not
parthenocarpic. The parthenocarpic character of Severianin is therefore recessive.
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