Abstract

Azolla, the water fern grows luxuriantly in cooler periods and the optium temperature ranges from 25-30°C. Due to the hot summer preceding the kharif season rice raised in the Cauvery Delta Zone, raising Azolla as dual crop in rice is not in vogue. Among the Azolla species, A. microphylla adopted itself to this environment at Aduthurai. The biomass production was adequate in summer to provide supply of inoculum for the ensuing Kuruvai crop. Azolla production ranged from 42 g/m²/day to 164 g/m2/day with a 60 day mean production of 92 g/m²/day during April-June, 1990. Despite a water temperature of 42°C attained at 2 PM, A. microphylla established well.

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