Planning Azolla Research for the 1980’s

Abstract

During the past five years interest in Azolla as a source of biologically fixed nitrogen for rice has increased dramatically. Azolla cultivation, which developed in conjunction with labor intensive lowland rice cultivation in northern Vietnam and coastal China, is now under study in one or more countries in Africa, Europe, South America, North America, and throughout much of Asia and Southeast Asia. In this paper we review the components of Azolla research we have found useful for evaluating Azolla as a nitrogen source for rice cultivated under mechanization in California, U.S.A. In chronological order these research areas are: defining the limiting conditions for Azolla production within a given region, screening Azolla populations for tolerance to these limiting conditions, optimizing Azolla productivity, and preliminary economic assessment. Concepts related to mechanization of Azolla cultivation and breeding more productive Azolla are also briefly summarized.