Age Environmental Factors, Germination And Seedling Emergence Of Ocimum Basilicum L

Abstract

Fresh and exhumed seeds of Ocimuni basilicum L. gave 100 % germination at 13/11-h alternating temperature of 20/10, 32/18, 38/24 and 40/32 °C but did not germinate at constant temperatures. Germination was prevented in the dark but occurred with a 13-h photoperiod. With increasing age, seed dry weight was reduced progressively as with speed and extent of germination; seeds 5 or more years old were not viable. There was 90% emergence from seeds sown on the soil surface but only 33% produced seedlings when buried 2 mm deep and emergence was 20% or less from those sown at depths of 5 mm or more. Mucilage by the seeds apparently helped to prevent desiccation. The ecophysiological significance of the result is discussed in relation to weed control in the Sudan Gezira.