FACTORS AFFECTING GERMINATION AND STAND ESTABLISHMENT OF PHYLLANTHUS-AMARUS (EUPHORBIACEAE)

Interest in Phyllanthus amarus (Euphorbiaceae) has been generated by r eports of antiviral activity and wide usage in traditional medicine. A ttempts at cultivation resulted in poor stands. The objectives of thes e studies were to determine the effects of light, storage temperature, age of seeds, time of dehiscence, and a scarification procedure on th e germination of P. amarus. Seeds of P. amarus require light to germin ate and thus should not be covered at sowing. Freezing did not signifi cantly affect the germination of dry seeds compared to seeds stored at ambient room temperature or higher, but storage at 10 degrees C was d eleterious. Percent germination was typically less than 50% and signif icantly decreased with time. Germination of freshly harvested seeds wa s slower than older seeds. Seeds from the first capsules to dehisce ha d a higher percent germination. A scarification procedure rendered see ds inviable. These results helped explain poor stands seen in field pl ots. In a previously planted plot, the re-established stand by natural reseeding was equivalent to that following intentional reseeding proc edures.