Juvenile Period in Plants: A Necessary Tool in Plant Breeding

Abstract

Plant juvenile period is the period between seed germination and its ability to achieve and maintain flower Hackett [1]. The duration of this period is determined by genetic and environmental factors Kazakov & Kichina [2], and their interaction can produce different plant behaviours Inmaculada et al. [3]. The benefits of traditional breeding practices however, are difficult to achieve in most crops, due to their long juvenile periods thus necessitating long breeding cycles. Two main strategies have been used in fruit breeding programs to overcome these difficulties which include the development of early selection criteria to eliminate genotypes with a long juvenile period and the shortening of this period by means of forced growth of seedlings. However, the length of the juvenile period has agronomic importance due to its relationship with the length of the unproductive period of the new cultivars subsequently reproduced by vegetative cuttings, an important character for fruit trees Inmaculada et al. [3], Experiments have being done on different crops to reduce the juvenile period by manipulating different growth factors and parameters as rapid flowering would hasten conventional breeding and help realize the benefits from genomic selection methods. The objective of this review is to briefly discuss on the juvenile phase of some crops and its effects on the breeding time thus delaying the improvements of those crops.