Effects of pH, photoperiod, and nutrient on germination and growth of Calymperes erosum C. Muell. gemmaling

Abstract

Effects of pH, photoperiod, and substrate nutrient concentration on the rate of germination of the gemmae and primary protonema growth of Calymperes erosum C. Muell. were studied. There was a statistically significant difference in germination of C. erosum gemmae and protonema growth among the different substrate pH levels, photoperiod treatments, and substrate nutrient conditions, respectively (P < 0.01). Gemmae germination and protonemal growth peaked at pH 4 and 5. Protonemal growth was retarded at pH 2, 3, 6, and 7. No germination was observed in continuous darkness. Germination and protonema growth increased significantly (P < 0.01) within the first 3 and 6 hours of daylight but not again until after 9 and 12 hours of exposure, respectively. No statistical (P > 0.05) increase in germination and protonemal growth was observed when the nutrient concentration was increased from 25% to 200%. Results indicate the moss is adapted to low nutrients and that it may germinate well at substrate pH as low as 2 howbeit the probability of establishment will remain limited until pH levels improve to 4 or 5. Furthermore, the moss is able to achieve net photosynthetic carbon gain during morning hours. Recovery from photoinhibition is likely by evening.