Towards Sex Determination of Date Palm

DOI: 10.1007/978-94-007-1318-5_26

ABSTRACT In the date palm (Phoenix dactylifera), a dioecious mode and late initial reproductive age of 5–10 years are major practical constraints to genetic improvement.
Improvement of the existing palm cultivars or selection of new ones with superior characters is a tedious endeavor due to
the long life cycle of the date palm tree and its heterozygous nature. Sexual propagation method cannot be used commercially
for propagating the cultivars of interest in a true-to-type manner. Currently there is no reliable method to identify sex
at the early seedling stage. Early sex identification of young seedlings could enhance breeding programs and generate experimental
male and female genetic stocks that will help the genetic improvement of the date palm. Moreover, the selection and identification
of superior seedling characters for yield enhancement and to improve the physical and chemical properties of fruits is of
great commercial interest. There has been significant progress in our understanding of sex-determining mechanisms in date
palm using traditional means. But physiological and cytological methods do not give obvious differences between male and female
date palms. Biotechnology, as a new tool in date palm breeding, can be useful to improve the qualities of palm trees through
early sex identification. Although molecular markers have been introduced in date palm programs, few research efforts have
been geared toward studying the early sex determination in the plant. This chapter will focus on genetic and molecular basis
of sex determination in date palm in attempting to develop reliable methods to identify sex at an early stage of seedlings.

KeywordsBiotechnology-Breeding-Sex determination-Molecular markers

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May 21, 2014