SEED GERMINATION AND SEEDLING VIGOUR IN SELECTED ACCESSIONS OF CYNODON DACTYLON (L.) PERS.

Four accessions of Cynodon dactylon were tested for their seed germination capacity and early seedling development from various locations in south western Nigeria. Germination percentage, germination rate parameters, seed vigour indices and seedling growth characteristic were determined under controlled conditions. Growth performance was consistently low for all the accessions (germination percentage ranged from 3.00 to 8.00%) and no significant differences were achieved between the accessions for germination percentage, germination index, seed vigour indices, mean germination time, time to first germination and coefficient of velocity of germination. Although germination was low, the seedlings that did grow showed measurable growth and large differences in some aspects of vigour. Accession A2 (IRUN) had the longest stolon (1.17 cm) and thickest culm (0.71 mm) among the accessions, suggesting better establishment potential than the other accessions. During the study period, no rhizome development was observed. The data indicate that germination is a major biological constraint in C. dactylon; this may be due to dormancy, polyploidy of the genome and reproductive irregularity. However, differences in the vigour of the seedlings showed that there were useful differences among accessions in establishment potential that could be utilized in breeding and germplasm improvement programmes.