The reaction of Lupinus angustifolius L. root meristematic cell nucleoli to lead.

The effect of 2-48 h treatment of Lupinus angustifolius L. roots with lead nitrate at the concentration of 10(-4) M on the nucleoli in meristematic cells was investigated. In the lead presence the number of ring-shaped as well as segregated nucleoli increased especially after 12-48 h of treatment, while spindle-shaped nucleoli appeared after 24 h and 48 h.

Proteins as nitrogen source for plants: a short story about exudation of proteases by plant roots.

Interest in the problem of plant nitrogen nutrition is increasing. Certain plants can use not only inorganic nitrogen, but also intact amino acids and short peptides. According to our studies, the roots of several agricultural and wild-living plants are able to exude proteases and by using them to create a pool of accessible N.

Degradation of proteins by enzymes exuded by Allium porrum roots - a potentially important strategy for acquiring organic nitrogen by plants.

Nitrogen is one of the crucial elements that regulate plant growth and development. It is well-established that plants can acquire nitrogen from soil in the form of low-molecular-mass compounds, namely nitrate and ammonium, but also as amino acids. Nevertheless, nitrogen in the soil occurs mainly as proteins or proteins complexed with other organic compounds.

The ability of plants to secrete proteases by roots.

The aim of our study was to find out if the culture medium of aseptically cultivated seedlings exhibits proteolytic activity and if this event is universal in angiospermous plants. Seedlings of 15 agricultural and wild-living plant species were cultivated for 14days without any addition of nutrients. Our studies showed that roots of higher plants could secrete proteases and that levels of proteolytic activity in the culture medium of individual species (and cultivars of the same species) could be significantly different.