Reproductive Effort of Some Annual and Perennial Plant Species: Impact of Successional Sequence, Habitat Conditions and Plant Size

The reproductive effort of some annual and perennial plant species was investigated with respect to successional sequence, habitat conditions and plant size. In the psammosere succession (dune succession), the reproductive effort (RE) of Cressa cretica and Atriplex griffithii was significantly greater in the early stage compared to that in late succession. Likewise, in relation to lithosere succession, Sporobolus arabicus, Pluchea lanceolata and Vernonia cenerescens all showed high reproductive effort in early part of succession compared to that of late succession. The annuals (S. arabicus and P lancolata) exhibited greater reproductive effort compared to the perennial species Vernonia cinerescens. Examination of the impact of site differences on reproductive effort showed that four grasses including Setaria intermedia, Chloris barbata, Cenchrus biflorus, and Eragrostispilosa were found to have significantly (P