Paper presented at the 52nd CFCS Annual Meeting, Guadeloupe, July 10-16, 2016
Figure 1.Wash and Age of Sargassum Interaction Effects on Number of Marketable Sweet Potato Tubers Sargassum Control Fresh Sargassum 4-week old Sargassum
Sargassum Washing Treatment Washed Unwashed 22.71 ab 20.28 a 22.63 ab 21.09a 21.69 ab 25.15b
Table 1. Effects of Wash and Age of Sargassum Treatment Interactions on Yield of Sweet Potatoes Conclusion The Sargassum mulch appeared to have some effects on the growth of sweet potato vines. The four weeks old unwashed Sargassum was most influential on yield, increasing the tonnes produced per hectare as well as the number of marketable tubers. This may be as a result of growth hormones found in the Sargassum that can stimulate root development (Sangha, Kelloway et al. 2014). The pest damage from Scarabee decreased with the same treatment which suggests that something in the Sargassum is deterring the weevils. This may be linked to the salt content given the treatment was unwashed but further investigation needs to be carried out. Varietal effects were observed showing that cultivar ‘E’ is a higher rising vine than cultivar ‘CBS 32’ while ‘CBS 32’ continually produced more leaves with greater chlorophyll indices than cultivar ‘E’. Chlorophyll indices were not increased by the application of Sargassum mulches. The drought conditions under which this experiment was carried out resulted in very low moisture levels in the soil but cultivar ‘E’ was able to keep more moisture in the soil. This cultivar produced taller plants but leaves were also wider, which may suggest that it covers the ground more efficiently to retain moisture. The results of this study showed potential benefits of Sargassum as a mulch in sweet potato cultivation but further work is needed to determine mulch effects with different cultivars on varying soils under non-drought conditions. Bibliografic references Lawrence, J., J. Bohac and M. D. Jackson (1999). Integrated Pest Management Collaborative Research Program Sixth Annual Report. I. CRSP. USA. Nazeer, A. (2011). Soils of the Caribbean. Kingston, Jamaica, Ian Randle Publishers. Sangha, J. S., S. Kelloway, A. T. Critchley and B. Prithiviraj (2014). Chapter Seven - Seaweeds (Macroalgae) and Their Extracts as Contributors of Plant Productivity and Quality: The Current Status of Our Understanding. Advances in Botanical Research. B. Nathalie, Academic Press. Volume 71: 189-219.
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