Germination of Six Grassland Herbs in Microsites with Different Water Contents

Abstract

The uniformity, rate of germination and final germination percentage of seeds of 6 grassland herbs in different micro-sites were studied under controlled conditions. Germination is affected specifically by increases in protection against water loss due to the shape of the micro-site. The uniformity, rate of germination and final germination percentage tended to decrease with less protection and lower water content of the soil in the order: Chrysanthemum leucanthemum L., Achillea millefolium L., Prunella vulgaris L., Rumex acetosa L., Plantago lanceolata L. and Hypochaeris radicata L. ssp. radicata. A field experiment also showed that germination of the 3 last-named species was greater and faster when they were more protected. From a description of the water uptake and loss it appeared that the species differed only with respect to uptake. In C. leucanthemum L. and A. millefolium L. more rapid water uptake is associated with better germination in drier micro-sites. The importance of seed shape and the development of a mucilage layer are emphasized. The ecological implications of the results are discussed briefly.