Volume 63, Issue 6
June 1966, pages 279-321
pp 279-282 June 1966
pp 283-287 June 1966
pp 288-296 June 1966
A decrease in the chloroplastic protein and a slight increase in the cytoplasmic protein were seen in the diseased leaves. There was no appreciable quantitative difference in the amino-acid contents of proteins of healthy and diseased plants. The total nitrogen content of diseased leaves showed a progressive increase over healthy during the day starting from the morning till evening. The free amino-acids of diseased leaves showed variations both in quality and quantity. Alanine, asparagine, arginine and aspartic acid were found to be in higher concentrations in diseased leaves, the increase being proportional to the severity of disease symptoms. The presence of two unidentified amino-acids was detected only in diseased leaves.
The amino-acids, alanine, asparagine, aspartic acid and arginine which were in very high concentrations in diseased leaves at 6 a.m. were observed to be either completely absent or present only in very small amounts at 6 p.m. A decrease in the C/N ratio resulted due to virus infection. This reduction could be attributed to the reduction in the carbohydrate content and increase in nitrogen content of diseased leaves.
pp 297-303 June 1966
pp 304-308 June 1966
1. The floral anatomy ofBurmannia pusilla is described in detail. Anatomically, the outer whorl of the perianth is sepaline and the inner petaline. The wing-like expansions of the flower are thought to represent the median lateral extensions of the sepals.
2. The inferior ovary is considered to be a result of adnation of floral whorls. The condition of the placentation is discussed and it is shown to be fundamentally parietal.
3. The presence of parenchymatous bands connecting the stamens with the style is reported for the first time. The condition is discussed in comparison with the androecial situation in the Apostasiaceae and in certain of the Orchidaceae, and in reference to the phylogeny of the Microspermae.
pp 309-312 June 1966
pp 313-320 June 1966
The vascular anatomy of the flower ofButomus umbellatus—a member of the Butomaceae—has been described. The perianth and stamens remain fused with the gynoecium up to the level of the locules and thus showing a tendency towards epigymy. The six carpels are also adnate among themselves at the base for some distance. The vascular supply of a carpel consists of a dorsal bundle and two ventral bundles. The latter ramify repeatedly and the branches are distributed on the lateral walls of the carpel.
The placentation inButomus has been described as ‘superficial’ since the ovules are distributed almost throughout the inner carpel wall except the dorsal suture. It is considered that in cases likeButomus where carpels are free, the superficial placentation might have originated from marginal placentation by the unequal extension of the ventral surface of the carpellary margins.
The present study also brings out certain resemblances in between Butomaceae and Hydrocharitaceae, while on the other hand vasculature of the flower hardly shows any resemblance to that of Alismaceae.
pp 321-321 June 1966 Erratum