In barley (Hordeum vulgare) leaves in which the water balance was not hampered, kinetin and abscisic acid effected the well documented decrease and increase, respectively, in RNase activity. When the plants were exposed to water shortage, leaf-water saturation deficit increased steadily, with kinetin enhancing and abscisic acid retarding the rise. Under drought, the pattern of hormonal effects ...

The application of kinetin (6-furfurylaminopurine) produces some effects similar to those induced by exposure to red light (Miller, 3, and Scott and Livermiian, 5). Both cause increased expansion of disks from bean leaves, greater elongation in stems and petioles of bean seedlings, and increased germination of lettuce seeds in the dark. Both treatments inhibit internodal elongation in excised p...

Exudation, (86)Rb transport, and water permeability were examined in excised roots of honey locust (Gleditsia triacanthos L.) treated by removing the tip 2 mm (tip-cut 2 mm) or tip 8 mm of the root, or by adding kinetin, or by both treatments. Tip removal increased the rate of exudation. Kinetin, 5 x 10(-6)m, inhibited exudation and Rb transport in tip-cut 2-mm roots; the inhibition was reversi...

Differentiation and morphogenetic potential of Allium commutatum Guss. callus tissue was investigated in five subcultures. Callus tissue was derived from root tips of in vitro grown seedlings and maintained on MS medium supplemented with 3% sucrose, 0.8% agar, 4.5 pM 2,4-D and 4.6 pM kinetin. Pieces of calli were subcultured on media with different concentrations and combinations of 2,4-D (1.0,...

Sionnnary. A comiparative study was made of the efffects of auxin (a-naphthalene acetic acid), kinetin (6-furfurylaminopurine) and a mixture of auxin and kinetin applied in vivo on synthesis okf RNA and protein and the distribution of such synthesis am'ongst the subcellular fractions of sections of endocarp from Kentucky Wonder pole beans (Phascolus vulgaris, L.). Auxin caused considerable enha...

Recently, we have reported the presence of kinetin (N6-furfuryladenine) in commercially available DNA, in freshly extracted cellular DNA and in plant cell extracts. We have also found that kinetin has electrochemical properties which can be used for monitoring the level of this modified base in DNA. Here, for the first time, we propose a mechanism for the formation of kinetin in DNA in vivo, ba...

Bioassays of tissue extracts show that high (500-1000 mug/liter) kinetin concentrations which permit growth of tobacco callus cultures on media without added thiamine activate the biosynthesis of this vitamin by the tissues. Although the tissue concentration of thiamine may fall appreciably, it is maintained at a level adequate for survival and slow growth of the cultures, and there is a large ...

The effects of 2 concentrations of kinetin, i.e., 2 and 4 mM together with 2 levels of drought stress, i.e., moderate (35% soil saturation capacity) and severe (20% soil saturation capacity) were investigated on the growth parameters of tomato including fresh and dry leaf weight, leaf number, leaf surface area, fruit number, fruit weight, and enzymatic antioxidants. To this end, first tomato pl...

In this study we investigated the influence of kinetin (6-furfurylaminopurine) on stolbur infected tomato plants. By using electron microscopy we analysed the starch accumula­ tion and the thylakoid membranes in the chloroplast and we quantified the photosynthetic pigments by spectrophoto­ metry. Consideration was also given to the growth and ge­ neral appearance of the plants. We proved that i...

Kinetin (N(6)-furfuryladenine) is a cytokinin growth factor having several anti-aging effects reported for human cells and fruit flies. We have observed that short-term culturing of human keratinocytes in the presence of 40 to 200 microM kinetin results in a significant inhibition of cell growth. Studies were undertaken to analyze the process of differentiation as a reason for growth inhibition...