Growth Requirements and Propagation of Date Palm

Abstract

The date palm (Phoenix dactylifera L.) produces dates, an important fruit crop in arid and semiarid areas that contributes to food security and economic development in developing countries. The present chapter aims at providing updated information on climatic requirements and propagation to contribute to the development of date production. Research has shown that temperatures ranging from 18 to 22°C during flowering and from 25 to 29°C during fruiting are best suited for successful production of date fruits. Areas with sufficient irrigation water or a shallow water table are needed for date palm production. Rainfall at flowering is detrimental, reduces pollination efficiency, and causes rotting and physiological damages at late khalal, rutab, and tamar stages of dates. Date palms also need abundant sunshine and well-drained, deep, sandy loam soils with a pH range of 8.0 to 10.0 and free from calcium carbonate. The production site should be protected from strong winds that may reduce fruit quality through blown dust and mechanical damage. Although seed propagation is possible, it is not recommended for propagation of commercial elite date palm cultivars because of its heterozygous nature and production of off-type progeny. Similarly, offshoot propagation is not appropriate for large-scale multiplication of commercial elite cultivars due to limited number of offshoots per tree. Micropropagation, however, permits large-scale multiplication of elite commercial cultivars. Organogenesis and somatic embryogenesis are the main micropropagation techniques implemented. However, in somatic embryogenesis technique, problems associated with callus induction, tissue browning, genetic variability, bacterial contamination, and abnormal somatic embryos have been observed and require further research, while in organogenesis, excessive time is needed for production of in vitro plantlets.