No abstract

Protoplasts were isolated from tissue fragments (<1 mm 2 ) of three Philippine cultivars of Kappaphycus alvarezii: the giant cultivar, cultivar L and Bohol wild type, by enzymatic dissolution of cell walls. Yields of viable protoplasts from young and old thalli (apical, middle, basal segments) were compared at various temperatures, duration of treatment and pH using eight combinations of commercial enzymes (abalone acetone powder and cellulase), and prepared extracts from fresh viscera of abalone (Haliotis asinina) and a terrestrial garden snail. Isolated protoplasts were grown in various culture media, temperatures, photoperiods and irradiance values to determine the conditions that favor germination and growth.Protoplast yields in tissues treated with commercial enzymes and the garden snail extract were lower than those obtained in tissues treated with fresh abalone extracts. Generally, the number of viable protoplasts increased with duration of enzyme treatment at 25 • C with a maximum yield of 8.2 × 10 3 g −1 tissue at 48 h. Yields were consistently higher in all cultivars at pH 6.1. The yields were also high from the middle segments of the giant cultivar (3.7 × 10 3 g −1 tissue) and Bohol wild type (4.5 × 10 3 g −1 tissue) treated with fresh abalone extract, and from basal segments of cultivar L and tissues treated with garden snail extract. The germination rate of protoplasts was highest (39.8%) at 25 • C and 20 µmol photon m −2 s −1 , using a 12:12 light dark photoperiod. The filament was 3.7 mm long by Day 5. These findings are relevant to developing cultures from protoplasts for genetic or strain improvement of K . alvarezii cultivars.Abbreviations: AAP, abalone acetone powder; Cel, cellulase; EP6, enzyme extract 6 (5% AAP + 2% Cel); UPV, University of the Philippines in the Visayas

Physical profile is significant reference to in addressing areas at risk due to fluvial processes and in establishing the physiographic maps especially in protected areas. Calbiga is one of the major rivers inside the Samar Island Natural Park (SINP). The source of Calbiga river was traced at the foot of Mt. Huraw of San Jose de Buan, Samar. The area is at the center of the Samar Island with an elevation of 850 meter above sea level (MASL). The river stretches 36.4 kilometers, with an average span of 44.57 meters, and average depth of 2.6 meters. The average height of the river bank is 7.67 meters, with rage of 5 -10 meters. Generally, the substrate was sand. On fluvial dynamics, the average water velocity is 0.20 mps with the average water flow of 18.64 m 3 /sec. The floodplain ranged from 10 -15 meters and 5 to 7 meters high. The river control measures are making a positive impact, though it could be reviewed to address the low elevation of the midstream. Rehabilitation measures at the watershed should be considered, parallel to the policy implementation of Disaster Risk Reduction Management (DRRM) measures.