Seed Germination and Seedling Development of the Seagrass Enhalus acoroides (L.f.) Royle in vitro: Effects of Burial Depths and Desiccation Periods

Abstract

This study provides information on the feasibility of using Enhalus acoroides seeds as source of seedling materials for seagrass restoration effort and to support wider conservation initiatives. Mature seeds of E. acoroides were collected from Tubajon, Laguindingan, Misamis Oriental and were subjected to different laboratory conditions, namely burial depths and desiccation periods, to determine germination rate, seedling growth, and development. Seeds placed just above (control) and half-buried in the sediment fully germinated on the first day, while germination of fully buried seeds was delayed, attaining 93.3% germination on the fourth day. Seeds planted at 5 mm burial depth started germinating on the fifth day with only 56.7% germination success, while seeds buried deeply (15mm) did not germinate. All seeds subjected to desiccation germinated, but higher seedling survival (93.3-100%) was observed when seeds were desiccated at shorter periods of up to two hours while the lowest seedling survival (64.8%) was observed after a 12h desiccation period. One-way ANOVA showed significant differences in seedling survival and shoot length (p<0.05) but differences in moisture loss and germination rates were not significant (p>0.05). Results have demonstrated that seed germination and the subsequent seedling development were adversely affected by burial depths and desiccation periods. Seedlings at 5mm burial depth and 12h desiccation period exhibited black and white spots, curled and yellowish leaves, stunted growth, and high mortality rates.