Abstract: Azolla Caroliniana may be growing in water and humid soils,which is a fern,ind possesses three morphology of"level-growing","Ascend-growing","Stand-growing".Experiments demonstrate that under the absolute lowest water-temprcrure 0-2℃ at more than fifty days non-series appearance in winter,and water-tempreture43℃ in summer have not death respectively.Ago the death difficulty of culturable Azollas have been overcome in winter and summer,and it create important and very benefit condition to developmental culture in great area.In fixed time surveying indicate that Azolla Caroliniana can increase yield in a year.Among them,4-6months grow most fast,and the accumulative yield of green manure may obtain 16700kgs permou in a year.By using the acetylene reduction method to test the activity of nitrogenase indicating Azolla Caroliniana obtain the amount of fixing nitrogen higher than Azolla imbricata.Therefore,it is a supreior and propriety culture variety in rice-growing region in the southern part of Henan.

Key words: Azolla Caroliniana, Culture, Utilizing