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A method for regenerating whole plants from nodal (axillary bud) cultures of seedlings was developed for flowering dogwood (Cornus florida L.). The seed source significantly influenced the rate of proliferation, although cultures initiated from each of the seven mother trees produced some shoots. Woody plant medium (WPM) was superior to either Murashige and Skoog or Schenk and Hildebrandt basal medium. 6-Benzyladenine (BA) at 2.2 or 4.4 μM stimulated the generation of significantly more useable shoots (≥1 cm) compared to all other concentrations (0.5-22.5 μM tested. Thidiazuron (TDZ) at 0.6 and 1.1 μM supported proliferation, but strongly inhibited shoot elongation. TDZ initiated cultures transferred to medium containing 4.4 μM BA produced usable shoots after five additional subcultures. Shoots generated adventitious roots when exposed to either a 12-h pulse of relatively high concentrations (246-1230 μM or continuous lower concentrations (0.5-49.0 μM of indolebutyric acid (IBA) for longer periods. Microshoots produced the significantly greatest number of roots when subjected to 4.9 μM IBA in WPM over a 4-week period. Whole plants were acclimatized to the laboratory conditions and subsequently to the greenhouse. The methodology described here should be useful in a breeding program by supplying multiple copies of unique, recombinant genotypes.

Studies on the occurrence of aquatic hyphomycetes were carried out in Panekal sulfur spring in the Western Ghats, India by incubation of leaf litter and analysis of natural foam and of induced foam. Sampling was done once every three months over a period of two years from September 1989 to June 1991. The temperature, pH, dissolved oxygen, and sulfide content of water were also measured. No fungi were observed within the spring, whereas 16 species belonging to 13 genera were isolated from two outflow sites of the stream. The percent frequency of Triscelophorus monosporus was high (24.0%). The temperature of water in the spring ranged between 30.0 and 38.5°C and the sulfide content between 3.2 and 4.3 mg 1(-1). Studies showed that sulfide water (4.0 mg 1(-1)) from the spring inhibited the growth of the colonies of Dactylella aquatica, Phalangispora constricta, Tetracladium setigerum, Vermispora cauveriana, and Wiesneriomyces laurinus. When the leaves colonized by aquatic hyphomycetes were incubated at different temperatures in sulfur-spring water and stream water separately, sporulation was not observed in any of the fungi at and above 35°C except Phalangispora constricta, which could sporulate at 35°C. At lower temperatures (15-30°C) relatively fewer species were found to sporulate in sulfur-spring water than in stream water.

A total of 98 medicinal preparations, involving 69 species of plants, used by the Siddis of Uttara Kannada in the state of Karnataka is described in this paper based on an ethnomedical field study. The finding includes 40 hitherto unknown medicinal uses of known medicinal plants. Among these, the use of the stem sap of Calamus thwaitesii as an antifertility drug, and the use of the flowers of Ichnocarpus frutescens and the rhizome of Hedychium coronarium in the treatment of diabetes are noteworthy. The knowledge of medicinal plants of the Siddis is distinct from that of another tribe of the same locality, the Gowlis.

Studies on the production of extracellular cellulase in two aquatic hyphomycetes Lunulospora curvula and Flagellospora penicillioides have shown that several factors such as carbon source, nitrogen source, pH and temperature affect the production of the enzyme. Experiments have shown that carboxymethyl cellulose is the best source of carbon, and ammonium sulfate is the best source of nitrogen for the production of the enzyme. An optimum pH of 5.2 and a temperature of 28 degrees C was found to favor maximum enzyme activity in 12-d-old cultures. Glucose and sucrose were found to suppress the activity of the enzyme in both organisms.

The effect of two herbicides (paraquat and 2,4-dichlorophenoxybutyric acid) and two fungicides (mancozeb and captafol) was studied on the growth of Flagellospora penicillioides, Lunulospora curvula and Phalangispora constricta using the poisoned-food technique. The pesticides did not produce any inhibition of growth at concentrations up to 5 mg/l. The required concentration to bring about total inhibition of growth varied among the chemicals and the cultures. The herbicides produced a slight enhancement of culture growth at concentrations ranging from 1 to 25 mg/l.