Influence of Kinetin, β-lndoleacetic Acid and Gibberellic Acid on Nuclease Activity of Bean (Phaseolis vulgaris) Hypocotyls

RESP-416

Phosphorus Compounds, Nuclease, and Phosphatase Activities in Healthy and Tumorous Stem Tissues of Datura stramonium L.

RESP-429

Changes in auxin activity in tumourous and normal tobacco calluses treated with morphactin IT 3233

The addition of morphactin IT 3233 in 1-40 mg/dm3 concentrations to the medium inhibited the growth in vitro of normal and tumourous tobacco calluses. The auxin activity (estimated by the Avena coleoptile straight growth test) of the acid ether extracts from these tissues increased. The activity of zone I (Rf 0.2-0.4, 0.5, solvent system: butanol:water:ammonia 10:10:1) in normal tissues increased more intensively than that of zone II (Rf 0.6-0.8, 0.9). In tumourous tissues, however, these changes were smaller and they concerned merely zone I of auxin activity (Rf 0.0-0.5). It seems that the mechanism of morphactin activity in both kinds of tissue is different. It may be supposed that the excessive accumulation of auxins induces growth inhibition of tissues. A previously found increase in the activity of IAA-oxidase influenced by morphactin might be considered as an adaptation to a higher level of IAA

Sugars in Iris pseudoacorus L. seeds

Qualitative and rough quantitative analyses of sugars occuring during the successive developmental phases in two poles - micropylar and chalasal - of the seeds of Iris pseudoacorus L. were made. Comparing the sugar dynamics of the respective developmental phases distinct differences were found in mature and immature seeds. Soluble polysaccharides being an initial form of accumulation do not occur in ripe seeds. No differences were found in the contents of insoluble sugars in chalasal and micropylar poles. The endoperm and the seed coat differ in the level of some sugars

Effects of indoleacetic acid, naphthalene-acetic acid, and kinetin on phosphorus fractions in hypocotyls of dwarf bean (Phaseolus vulgaris): With two Figures in the Text

RESP-433

Phosphorus compounds in callus tissue of Nicotiana tabacum L. treated with morphactins IT 3233 and IT 3456

The morphactins under examination blocked the growth of tobacco callus tis-sues at as low concentrations as l mg/dm3 (IT 3456) and 10 mg/dm3 (IT 3233). The growth inhibition was accompanied by an increase in dry matter content. An increment in total P level induced by morphactins was the result of inorganic P accumulation. It could be supposed that the compounds tested influence the permeability of plasma membranes. No direct relationship his been found between the action of morphactins on growth and the level of phosphorus compounds in tissues. It seems that both the morphactins have a little different mode of action