Abstract
Three populations of Tephrosia uniflora Pers. were studied in various habitats of the southern Sindh, namely: (i) rocky soil (ii) calcareous sandy loam soil and (iii) saline sandy soil. The populations differed considerably with regard to number of flowers and fruits per plant. The mean seed weight of Tephrosia uniflora for the saline soil population was 0.0214g 0.00076, for calcareous soil 0.0276g 0.00081 and for the rocky soil population it was .0184g 0.0074. Seed weight variation within pods showed that seeds at distal end of 5-seeded pods of Tephrosia uniflora had lower weight in saline habitat. In calcareous sandy loam soil, seeds at distal end of 4,5 and 7-seeded pods had lower weight. In rocky soil distal end seeds of 4,6,7,8 and 9-seeded pods had lower weights than the rest of the seeds though such differences were non-significant.. Tephrosia uniflora exhibited external seed dormancy owing to hard seed coat which could be broken by physical scarification or puncturing the seed coat. Large seeds of Tephrosia uniflora invariably produced larger seedlings than those produced by smaller seeds. The crude reproductive effort of Tephrosia uniflora was high and it was highest for the population associated with saline soil.
