Abstract

This is a review paper discussing the different types of exudations by the plants. Both natural and artifically induced exudations are described. The first part of the paper deals with the different types of natural exudations including guttation, exudation due to root pressure, natural root exudation, exudation of nectar, salt glands and pathological exudation. Enriched exudation from leafless perennials like maple sap exudation is also described. The maple sap, although sugary, has its origin in the xylem. Exudation from the pholem is another part in this chapter. Pholem sap exudation from monocotyledons and dicotyledons are treated separately. Apart from sugar saps, there are other exudates originating usually in the bark of plants. Examples described in the chapter include latex, resin and mucilage exudations. Some description is given on the pholem tapping by aphids. The mehanisms of the various exudations are dealt with in this chapter. The chapter gives 84