The effects of differing cytokinin and auxin concentrations on resistance of tobacco (Nicotiana tabacum L.) tissue cultures to race 0 of Phytophthora parasitica var. nicotianae were examined. With 1 micromolar kinetin and either 11.5 micromolar indoleacetic acid or 1 micromolar 2,4-dichlorophen-oxyacetic acid, tissues from resistant cultivars exhibited a "hypersensitive" reaction to zoospores o...

Of nine plant growth regulators (indoleacetic acid, 1-naphthalene acetic acid, gibberellic acid, giberellin 4/7, 6-benzylaminopurine, 6-furfurylaminopurine, abscisic acid, and 1-aminocyclopropane carboxylic acid) tested, only 6-benzylaminopurine and abscisic acid affected (14)C-photosynthate unloading from excised seed coats of Phaseolus vulgaris L. Unloading, in the presence of KCl, was stimul...

The enzymatic oxidlation of 3-indoleacetic aci(l (IAA) which was first described in detail by Tang and Bonner (16, 17), has been observed in several types of plants, e.g., fungi (13), ferns (14), monocotyledonous plants (20), and dicotyledonous plants (16, 17, 19). Although differences have been observed in regard to the enzyme's requirement for a phenolic cofactor, and in the pH optimum, the r...