Stem and root tumors and teratomata may be induced in tobacco plants (Nicotiana tabacum L., var. One Sucker) by total debudding. Intact plants or plants only decapitated produced no tumors or teratomata throughout their life time. These findings suggest a possibly important oncological relationship between normal growth and tumorous growth. Prevention of normal regeneration (apical and axillary...

The polyamines (PAs) putrescine (Put), spermidine (Spd) and spermine (Spm) (Fig. 1) have been shown to be involved in a variety of plant growth and developmental processes, including cell division, vascular differentiation, root initiation, shoot formation, flower initiation and development, fruit ripening and senescence and embryoid formation in tissue cultures (Evans and Malmberg, 1989; Galst...

Lycopodiophyta-consisting of three orders, Lycopodiales, Isoetales and Selaginellales, with different types of shoot apical meristems (SAMs)-form the earliest branch among the extant vascular plants. They represent a sister group to all other vascular plants, from which they differ in that their leaves are microphylls-that is, leaves with a single, unbranched vein, emerging from the protostele ...

A split-root growth system was employed to evaluate the effect of NaCl on nodule formation by soybean (Glycine max L. Merr. cv Davis). By applying the salinity stress and rhizobial inoculum to only one-half the root system, the effects of salinity on shoot growth were eliminated in the nodulation process. Rhizobium colonization of inoculated root surfaces was not affected by the salt treatments...