Suboptimal N nutrition increased the water potential for stomatal closure in water stressed cotton (Gossypium hirsutum L.) leaves. This increased sensitivity to water stress had two components, increased accumulation of abscisic acid (ABA) and increased apparent stomatal sensitivity to ABA. Low N increased the threshold water potentials for stomatal closure and ABA accumulation by about 4 bars ...

Supraoptimal concentrations of indoleacetic acid (IAA) stimulated ethylene production, which in turn appeared to oppose the senescence-retarding effect of IAA in tobacco leaf discs. Kinetin acted synergistically with IAA in stimulating ethylene production, but it inhibited senescence. Silver ion and CO(2), which are believed to block ethylene binding to its receptor sites, delayed senescence in...

Observations were made of the effects of several plant regulators, indole-3-acetic acid, kinetin, abscisic acid, and gibberellic acid, as well as of extracts prepared from leaves and fruit stalks on the respiration pattern, ethylene production, and the number of days to ripen of avocado fruits (Persea americana Mill.). These substances were vacuum infiltrated to insure good penetration and dist...

We examined the effects of various adenine analogues on the growth and differentiation of human myeloid leukemia HL-60 cells. Some of these analogues inhibit growth and induce nitroblue tetrazolium reducing activity in HL-60 cells. Cytokinins such as kinetin, isopentenyladenine, and benzyladenine were very effective in inducing nitroblue tetrazolium reduction and morphological changes in the ce...

The accumulation of chlorophyll, production of two specific lamellar chlorophyll-protein complexes, onset of O(2) evolution, and detection of P700 were examined in intact Jack bean (Canavalia ensiformis [L.] D.C.) leaves treated with 10(-5)m kinetin or benzyladenine and allowed to green under low (30-35%) and high (80-85%) relative humidity. In contrast to reports of the promotion of chlorophyl...

Suspension cultures of Pueraria tuberosa, a woody legume, have been established and using different concentrations of growth regulators, sucrose, ammonium and nitrate nitrogen, attempts have been made to improve their isoflavonoid content. The cell cultures grew well on all the treatments. Up to approximately 8 folds increased isoflavonoids content was recorded in the cultures grown in MS mediu...