5.2% of the seeds originate from self-pollination of the female parent. (We obtained 4.5%
selfing in 1976 in a similar experiment but without fruit by fruit extraction of the seeds). The
best part of this percentage was obtained from a few fruits which yielded 100% seeds issuing from
self-pollination. The frequency with which these fruits were obtained at certain times during the
flowering period was high.
However, it is impossible to conclude from our data to what extent dehiscence of the
stamens of ps-2 flowers is encouraged by emasculation and to what extent it occurs naturally and
independently of the latter operation (due to wind, dry weather etc.).
Rao, R. N., and Panuganti N. Rao A highly sterile unstable tetraploid of tomato.
Among the colchicine induced tetraploids of tomato var. Marglobe, one showed low multi-valent
formation at diakinesis (average fre- quency of 1.1 quadrivalents per cell), but meiotic abnormalities like
multipolar spindles (1-5 with varying number of chromosomes in each) at metaphase I, laggards
at anaphase I and several groups (up to 4) of chromosomes at telophase I etc. were found in
most of the cells. Pollen sterility was very high (85.00%). Whether similar irregularities also
occurred on the female side leading to sterility could not be ascertained as the plant was growing
and flowering in the field in April-May with rising summer temperatures resulting in flower
abscission despite pollinations with normal tetraploids. In the diploids and other tetraploids also
growing in the same period, fruiting was found to be scanty, though meiosis in PMC's was normal
with good pollen fertility. The type of meiotic abnormalities found in the sterile tetraploid is
apparently an indication of its instability and tendency towards breakdown into lower levels of
ploidy.
Rao, R. N., and Panaganti N. Rao A purple
stigma variant in Lycopersicon glandulosum.
One plant in a population of L. glandulosum (seeds
obtained from Plant Introduction Centre, Indian
Agricultural Research Institute, New Delhi; Acc.
No. EC 66003, Ex
U.S.A.) raised through open pollinated seed for three generations here in Botany Experimental Field
Station showed purple coloration of the stigma. This is evident even at the bud stage and persists till
withering of the stigma. Other characters associated with this color variation are the prominent
exsertion of the style (largely due to the down-curling of the sterile tip of the staminal cone),
shorter staminal cone, and reduction in diameter of the open flowers. Compared to normal
sibling plants, the overall length of the style is actually shorter but it is more exposed only due to
the shorter anther column. The magnitude of differences in all these characters between the variant
individual and the normal siblings is given in table below. The nature of association of these
characters with coloration of the stigma is under investigation.
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