ABSTRACT
Earthworms are important soil-dwelling organisms that contribute greatly to increasing fertility of soils to support productive crop and natural plant growth. They create channels aerating soil that allow ef¤cient gas exchange between soil and plant
CONTENTS
I Introduction .................................................................................................. 129 II Effects of Vermicomposts on the Growth of Field Crops ............................ 131 III Methods of Vermicompost Applications to Field Soils and Their
Effects on Plant Growth and Yields ............................................................. 131 IV Rates of Vermicompost Applications and Their Effects on Plant
Growth and Yields ........................................................................................ 133 A Peppers ................................................................................................... 134 B Tomatoes ................................................................................................ 137 C Strawberries ........................................................................................... 137 D Grapes .................................................................................................... 137
V Effects of Vermicomposts Produced from Different Materials on Plant Growth and Yields .......................................................................... 138
VI The Economics of the Use of Vermicomposts in Field Crops ...................... 140 VII Physicochemical and Biological Changes in Soils in Response
to Vermicompost Applications ..................................................................... 141 A Physicochemical Changes in Soils ......................................................... 141 B Biological Changes in Soil ..................................................................... 147
VIII Conclusions ................................................................................................... 148 References .............................................................................................................. 148
roots. They support symbiosis among soil-dwelling microorganisms and promote overall microbial activities. Earthworms also facilitate the mineralization of nutrients during the breakdown of organic matter, thereby supplying nutrients for plant growth. Earthworm biology, ecology, and bene¤ts in natural and agricultural soils have been documented in numerous publications since the Darwin’s 1881 book The Formation of Vegetable Mould, through the Action of Worms. It has been demonstrated clearly that some species of earthworms are specialized to live in decaying organic matter; these are termed epigeic species (Edwards and Bohlen 1996). Some earthworms are able to process sewage sludges and biosolids from wastewater; brewery wastes; processed potato wastes; waste from the paper industries; food wastes from supermarkets and restaurants; animal manures from poultry, pigs, cattle, sheep, goats, horses, and rabbits; and horticultural residues from dead plants, yard wastes, and wastes from the mushroom industry (Edwards and Neuhauser 1988; Edwards and Arancon 2004). The ability of some species of earthworms and microorganisms to process organic wastes has been developed in a technical process termed vermicomposting.
