ABSTRACT
Introduction and overview Research into the postharvest behavior of fruits and vegetables has a long history. In the 1930s most of the physiological effects of ethylene on plants had already been described (Pech et al., 1992), and after this period ethylene became the object of numerous studies due to commercial interest related to its action on the ripening and conservation of fruit. After a long time using ethylene in growth and development manipulations, it was presupposed that this gas was an endogenous growth regulator. The ethylene biosynthesis pathway has now been completely elucidated due to advances in molecular biology and signaling receptors (Binder, 2008; Cara and Giovannoni, 2008) based on the Yang cycle (Yang and Hoffman, 1984). The discovery of the ethylene biosynthesis pathway has been a crucial step in the isolation of the two main regulatory enzymes from the precursor S-adenosylmethionine (SAM) to form 1-aminocyclopropane-1carboxylic acid (ACC) by ACC synthase (ACS) and the conversion of ACC to ethylene by ACC oxidase (ACO) and their encoding genes.
