Studies on Oversowing of Natural Grasslands in Kenya 1. The Effects of Seed Threshing, Scarification and Storage on the Germination of Desmodium Uncinatum (Jacq.) DC.

Abstract

The seeds of many plant species pass through a period of dormancy soon after maturation. They do not germinate at this time even when conditions of moisture, aeration and temperature are favourable. The cause may be of a physiological nature, but particularly in legumes, is often due to an impervious seed coat preventing the entry of water (Hyde 1954) or of oxygen and carbon dioxide (Brown 1960). In many legumes this is coupled with the occurrence of chemical growth inhibitors (Nutile 1945). The mechanical removal or scarification of the seed coat usually aids the germination of "hard" seeds. Physiological seed dormancy may also be broken by exposure to light, low or high temperatures and chemicals such as chloroform and sulphuric acid.