Effect of proanthocyanidins and catechins isolated from diverse plant sources was studied on the growth ofLemna paucicostata Hegelm. There was no difference in DNA contents ofLemna plants in any of the treatments. Soluble nitrogen content was less at the concentrations promoting maximum growth ofLemna plants as compared to the control. RNA and protein nitrogen contents increased as growth was promoted by certain concentrations of proanthocyanidins and catechins. The possibility of growth regulation by proanthocyanidins and catechins through nucleic acid and nitrogen metabolism is discussed.

One of the aquatic monocotyledonous taxa commonly distributed throughout India and Ceylon has been placed underVallisneria, Lagarosiphon andNechamandra thereby indicative of its unsettled nomenclature. This is now clarified and solved on the basis of the discovery of the staminodes that have been overlooked and/or misinterpreted by the earlier authors. The basis for this baffling situation resulting in the nomenclatural problem and the different descriptions of this taxon as given by the earlier authors have been discussed with reference to the present observations and interpretations. The summation of the results based on the newly discovered exomorphological structures (staminodes) strengthened by the interpretations as supported by and relevant to the traditional theoretical understanding thenomen of the taxon under debate is established asLagarosiphon alternifolia (Roxb.) Druce. Emended description and economic importance are given.

Large number of plantlets were obtained in hypocotyl cultures ofSantalum album either through direct differentiation of shoot buds and their subsequent induction into rooted plants or through callus induction and somatic embryogenesis. Factors which triggered both these morphogenetic processes were investigated.

Embryology ofCtenolepis garcini Hook. was studied in detail and is described and illustrated.

Scanning electron microphotographs of seed surface patterns of three wild and five cultivated species ofVigna are provided and described. The seed surface patterns are species-specific and showed no interpopulation variation. To promote the use of technical terms in SEM studies of seed surface and to serve as a ready reference a table explaining the 13 terms adopted by us is given. The importance of study of seed surface especially in taxonomy is discussed.

The reproductive morphology ofHoppea fastigiata has been studied and described. Evolutionary trends in the subtribe Erythraeinae are highlighted.

A new species,Brachiaria munae Basappa, from South India, is described and illustrated.

Embryology of three species ofEhretia (E. ovalifolia, E. microphylla andE. laevis) is described. The anther is tetrasporangiate and the wall corresponds to the ‘Dicotyledonous’ type. Reduction divisions in microsporocytes are simultaneous and tetrads are tetrahedral and decussate. Occasionally, isobilateral tetrads are met with. Polyspory is common. The pollen grains are usually shed at the two-celled stage. The ovules are anatropous, unitegmic and crassinucellar. An endothelium differentiates. Both Polygonum and Allium types of megagametophytes coexist. The endosperm is Cellular with four-celled micropylar and four-celled chalazal haustoria. Embryogeny is of the Onagrad type, and suspensor is four-celled.

Electrophoretically separated peroxidase isozymes and soluble seed protein profiles of some of the viable mutants of green gram in theM4 generation have revealed qualitative and quantitative variations from the parental line. Some of the mutants exhibited increased or decreased soluble protein bands according to the altered genetic architecture. The study of the similarity index of the soluble seed protein profiles indicated varying degrees of homology ranging from 40 to 83% among the parental line and mutants.

Ethephon (2-chloroethyl phosphonic acid) andavg (amino ethoxy vinyl glycine), was administrated in a young healthy tree trunk ofAcacia auriculiformis. Induction of heartwood occurred as a result of ethephon treatment and it increased with increase in its concentration.avg treatment showed production of coloured wood only and its formation was more inhibited at a concentration of 500 ppm which indicates thatavg inhibits the action of ethylene produced by even injury to the wood. The sapwood, sapwood-heartwood boundary and heartwood of a normal disc, coloured wood and induced heartwood were histochemically analysed.