Seaweeds gain importance recently in agriculture as several studies have shown that chemicals extracted from seaweeds are used as soil amendments to increase crop yield. We report here the positive effects of brown seaweed Sargassum wightii on paddy when applied as mulch during transplantation trials carried out in a progressive farmer’s field. Besides appreciable levels of Na, Ca, Mg, Fe and Zn, the NPK ratio in dry Sargassum mulch was 1:0.1: 1.8. The advantage of mulching dry seaweed to the paddy field was exhibited by mild increase (2.6%) in the organic carbon content of soil within 30 days of mulching and considerably higher (23.6% after 45 days and 35.2% after 80 days) over the control field. Height of the saplings also exhibited significantly higher value over the control (p<0.05, n=25), whereas the number of tillers were slightly more in control plot. Mulching Sargassum to paddy also increased the number of seeds in a panicle as well as the grain weight than the control.

Seaweed manure, micronutrients, plant growth hormones, soil organic carbon, proximate composition