Azolla-Anabaena as a Biofertilizer for Rice Paddy Fields in the Po Valley, a Temperate Rice Area in Northern Italy

Table 1

Means and Standard Deviations of Carbon and Nitrogen contents (d.w.%) and C/N ratio in Azolla strains from Dec. 2000 to May 2001. We observed high quantities of Nitrogen in the leaves of the Japan and Italy strains; it was probably related to the decrease of its biomass during our test. The Milan strain showed lower Nitrogen content, but a good C/N ratio associated with a high RGR (see Figure 1).

Strains		%C	%N	C/N
Milan	mean	38.854	2.581	15.582
	std	1.66	0.48	2.58
Sweden	mean	37.722	2.097	18.166
	std	2.04	0.18	1.73
Germany	mean	38.244	2.248	17.165
	std	1.87	0.18	1.60
Italy	mean	40.374	2.631	15.606
	std	0.98	0.33	2.08
Japan	mean	41.294	3.025	14.336
	std	1.26	0.59	3.66