WILD POINSETTIA (EUPHORBIA-HETEROPHYLLA) GERMINATION AND EMERGENCE

Wild poinsettia germination was at least 95% when exposed to solution pH of 2.5 to 10 or solution osmotic potential of up to -0.8 MPa, No ge rmination was observed at pH 12 or osmotic potential of -1.5 MPa. Ligh t was not required for germination. Seed germinated at temperatures ra nging from 20 to 40 C with maximum germination of 97% at 35 C. Wild po insettia had the highest emergence (80%) from seed placed 2 to 4 an be low the soil surface, while 20% of the seed planted at 14 cm emerged. Wild poinsettia germinated over a wide range of conditions, which expl ains why it is becoming an increasingly serious problem.