Method for the mass production of seedlings of the tropical brown seaweed (Phaeophyceae, Ochrophyta).

Farming of to produce harvestable crop can be a challenging task to seaweed farmers.•Sexually-produced seedlings can be propagated in a hatchery using 140-liter plastic tanks connected with PVC pipes and seawater supply directly pumped from the sea, passing through a filter system.•First step of this method is to collect large amount of fertilized eggs from special branches called receptacles, found at the ends of lateral branches of , excised from fertile thalli during its spawning season and collecting their eggs for recruitment into artificial substrate tanks.

Examination of prezygotic and postzygotic isolating barriers in tropical Ulva (Ulvophyceae, Chlorophyta): evidence for ongoing speciation.

Phylogenetic clades based on DNA sequences such as the chloroplast rbcL gene and the nuclear ITS region are frequently used to delimit algal species. However, these molecular markers cannot accurately delimit boundaries among some Ulva species. Although Ulva reticulata and Ulva ohnoi occasionally bloom in tropical to warm-temperate regions and are clearly distinguishable by their reticulate or plain blade morphology, they have few or no sequence divergences in these molecular markers and form a monophyletic clade.

Immunofluorescent detection of ice-ice disease-promoting bacterial strain Vibrio sp. P11 of the farmed macroalga, Kappaphycus alvarezii (Gigartinales, Rhodophyta).

A specific immunofluorescent probe consisting of polyclonal antibodies was developed to detect a marine bacterium, Vibrio sp. strain P11, which was found in a previous study to promote the ice-ice disease in the cultivated red macroalga, Kappaphycus alvarezii. The method involves a combined application of the fluorescent stains, 4',6-diamidino-2-phenylindole (DAPI) and the P11 PAbs, into a homogenized seaweed sample (<1 g wet wt), which is prediluted to make bacteria countable under an epifluorescence microscope without serious interference from autofluorescing algal debris.