The Initiation of Developmental Drifts in Excised Plant Tissues

Abstract

Excising plant tissue initiates changes in respiration and other biochemical processes, potential solute accumulation, and fine structure, which continue over several days (Van Steveninck 1964; Jackman and Van Steveninck 1967; Laties 1967; ap Rees and Royston 1971; Bryant and ap Rees 1971; KahI1971). These may all be part of a single developmental process, as is suggested by the observation that low temperature, a nitrogen atmosphere, and certain metabolic inhibitors slow down the changes in both respiration and solute accumulation (Rees 1949; ap Rees 1966; MacDonald et al. 1966). It is not known how these changes, which take place in a constant environment, are regulated, and in particular it is not known what factor associated with excision initiates them. Comparisons of intact and freshly excised tissues have shown numerous biochemical and fine structural changes (Laties 1962; Jackman and Van Steveninck 1967; Jacobson et al. 1970; Adams and Rowan 1971; KahI1971; Rungie and Wiskich 1972). One can conclude from these initial changes that the initiating event(s) must be fairly rapid.