Effect of exogenous natural plant growth regulators (PGRs) on the morphology, growth, and nutrient of sea grapes (Caulerpa racemosa)

Caulerpa racemosa is a nutritious food option that has high demand. However, the production rate is lagging behind the increased demand. The objective of this study was to determine the effectiveness of aqueous extract from various plants as an exogenous plant growth regulators (PGRs) in the morphology, growth, and nutrition of C. racemosa. The natural PGRs used were coconut water (CW), shallots and coconut water (AESCW), maize (AEM), moringa leaves and mung beansprout (AEMBS), and Kappaphycus alvarezii (AEKA). Fifty grams of C. racemosa was soaked on the natural PGRs and was cultivated for 30 days with a sandy mud substrate. The results showed that the soaking of C. racemosa on natural PGRs had a significant effect (p < 0.05) on absolute growth, specific growth rate, and nutrients. C. racemosa soaked in aqueous shallot and coconut water showed the best absolute growth (214.32 +/- 7.68 g) and SGR (5.55 +/- 0.08%/day); meanwhile, C. racemosa soaked in coconut water had the best nutrition (protein, 9.54 +/- 0.16%; fiber, 1.37 +/- 0.21%; and fat, 0.42 +/- 0.04%). The morphological analysis showed that soaking C. racemosa on natural PGRs resulted in long fronds, bigger stolons, a greener and fresher color, and more ramuli.