Cultivation of the edible green seaweed Gayralia (Chlorophyta) in southern Brazil.

Abstract??During the last two decades, the monostromatic green seaweedGayraliasp. has been harvested sporadically by local fishermen on the Paran? coast of southern Brazil and sold to Japanese restaurants. However, the production is erratic and its economic impact very small. This paper provides basic information about a technique to cultivate this seaweed on suspended nets in Paranagu? Bay, southern Brazil, aiming to develop a more reliable and sustainable source of income for impoverished coastal dwellers.Gayraliasp. occurs year round in the region, usually growing on mangrove stems and roots. Polypropylene nets (10?m long ? 1?m wide with 16?cm mesh) were placed close to the mangrove fringe. Recruitment occurred year round reaching a peak of 500 recruits m?2during early spring. Higher recruitment occurred at periods of low temperature (21?23?C) and high salinity (30?33 psu). Growth rates ofGayraliasp. ranged from 5.75 ? 0.56% to 6.50 ? 0.43% day?1during the winter and from 1.43 ? 1.65% to 4.65 ? 2.17% day?1, during the summer. Production ranged from 22 ? 6?g m?2DW in June to 58 ? 21?g m?2DW in September 2004 in 45 days after zooid settlement. The simplicity of the cultivation method, reasonable growth rates and extensive favorable area for cultivation suggest that mariculture ofGayraliasp. may become a good alternative of income for the local inhabitants. [ABSTRACT FROM AUTHOR]