Resumen:
It´s known that the cyanobacteria Anabaena provides nitrogen species at the host fern Azolla caroliniana due to the enzymatic activity of the iron and the molybdenum proteins that fix the nitrogen into the cell. These enzymes could be inhibited by the elevated concentration of nitrogen species in the aqueous media being a stressing condition for Anabaena. The nitrogen is a constituent of the porphyrin ring of the chlorophylls, without this element the rings will have no shape and even exist. In the absence of chlorophylls the cell uses auxiliary pigments such as carotenoids and phycobiliproteins. For this reason is probably that the Azolla c. leaves become red before the proliferation of the nitrogen species in the aqueous media. By this, it has been proposed two analyses, In vivo and In vitro. These analyses evaluate the nitrogen species levels in the aqueous media, relating the red coloration in Azolla c. leaves. The results of the analyses from soil, water and leaves from (Azolla c. & rice) showed that the nitrogen chemical species inside the water of the Azollario (Azolla c. cultivated in water) doesn´t have significative variations that involves the coloration of Azolla c. In the Azorizario (paddy & Azolla c. cultivated in water) a deficit of potassium in soil was recorded, indicating a disproportional fertilization of soil. In other sample point the presence of green algae was found, which presumably would be the cause of the chlorosis and brown spots in rice leaves.
