(14)C-methylene labeled IAA was used to determine the influence of reorientation with respect to gravity on auxin transport in Zea mays L. coleoptile segments. It was observed that inversion of the segments leads to a decrease in the capacity to transport (14)C-IAA basipetally, as well as, in certain instances, the linear velocity of that transport. Segments were also reoriented horizontally, a...

THE MAIN RESULTS PRESENTED IN THIS ARTICLE MAY BE SUMMARIZED AS FOLLOWS: 1. A test method with deseeded Avena seedlings for small concentrations of auxin and precursors of auxin has been described. 2. This method makes possible quantitative determinations of about ten times as low concentrations of hormone as can be obtained with the standard method, (a) Through an increase in the time of the t...

BACKGROUND AND AIMS Anoxia-tolerant plant tissues synthesize a number of proteins during anoxia, in addition to the 'classical anaerobic proteins' involved in glycolysis and fermentation. The present study used a model system of rice coleoptile tips to elucidate patterns of protein synthesis in this anoxia-tolerant plant tissue. METHODS Coleoptile tips 7-11 mm long were excised from intact se...

A lab experiment was conducted to evaluate the effect of chromium (Cr) on seed germination, root elongation and coleoptile growth in pigeon pea (Cajanus cajan). The seed of the pigeon pea was treated with five concentrations of Cr (0, 20, 40, 80 and 100 ppm). The results indicated that the per cent germination of test crop was decreased after application of 20 ppm Cr concentration. The effect o...

Phytotoxicity assessments were performed to compare responses of Typha latifolia (L.) seeds to atrazine (only) and atrazine + S-metolachlor exposure concentrations of 0.03, 0.3, 3, and 30 mg L(-1), as well as permethrin exposure concentrations of 0.008, 0.08, 0.8, and 8 mg L(-1). All atrazine + S-metolachlor exposures resulted in significantly reduced radicle development (p < 0.001). A stimulat...

Treatment of living protoplasts from the Avenia coleoptile with enzymes and chemicals has provided new information about the external surface of the plasma membrane. Treatments with selected detergents and polyene antibiotics indicate that little sterol is present. The lysis of protoplasts in carboxymethyl-RNase which is enzymatically almost inactive provides strong evidence that the lysis prev...