S Sundara Rajan
Articles written in Proceedings – Section B
Volume 75 Issue 4 April 1972 pp 167-176
Ovules are anatropus, unitegmic and tenuinucellate. A hypodermal archesporial cell directly functions as the megaspore mother cell. Embryo sac development is of the Polygonum type. More than one megaspore in the tetrad show signs of development. Organised embryo sac is six-celled with only two antipodals. A secondary multiplication of nuclei in the antipodal cells results in a variable number of nuclei.
Endosperm is of the
Embryogeny conforms to Asterad type.
Fruit wall has a thick layer of tannin cells in the hypodermal layers.
Volume 77 Issue 1 January 1973 pp 19-24
The embryology of
Volume 79 Issue 6 June 1974 pp 267-282
Morphology and embryology of
Fertilisation is porogamous, endosperm is
In the mature fruit, the wall is five layered with the innermost layer infested with tannin. Endosperm persists as a thin layer adhering to the integument which itself is three layered.
Volume 80 Issue 1 July 1974 pp 18-25
Floral parts arise in acropetalous succession. A transection of an young anther lobe shows a layer of microspore mother cells surrounded by tapetum, a middle layer, an endothecium and an epidermis. Microspore tetrads are decussate and tetrahedral. Tapetum is glandular. Pollen grain is shed at the 3-nucleate stage. Endothecium exhibits fibrillar thickenings.
Embryosac development is of the polygonum type. Placental nutritive tissue is present only at the micropylar region. Embryosac is surrounded by the endothelium only at the central region.
Fertilisation is porogamous and endosperm is
Volume 84 Issue 4 October 1976 pp 124-127
It has been shown by statistical methods that in Angiosperms significant correlation exists between micropyle formation by both the integuments and six other floral and vegetative characters which are admittedly primitive. A subjective assessment of the primitiveness of the feature in question (
Volume 84 Issue 5 November 1976 pp 180-184
Embryo sac development conforms to Polygonum type. Starch grains are noticed in the embryo sac right from the megaspore mother cell stage. Twin tetrads one with a chalazal functional megaspore and another with a micropylar functional megaspore have been noticed in some ovules. While 75% of the embryo sacs have normal polarity, in 20% of the ovules reverse polarity has been noticed. In the remaining 5% of the ovules, ‘bipolarity’ has been observed. Reverse polarity in relation to double archegoniate theory has been discussed.