Micropropagation of Juglans regia L.

Juglans regia L., commonly called walnut, is a nutrient-rich fruit. Besides many therapeutic properties, the plant is highly valued for its timber, which along with the fruit-nut, fetches a very high demand in the domestic and international markets. The ever increasing demand for these plant products is not being sufficed by the existing supplies. This is owing to the fact that conventional methods of walnut propagation are time and space-consuming and show limited responsiveness. Walnut cuttings are also difficult to root, making large-scale propagation a challenge. Consequently, walnut micropropagation has become extremely important to ensure rapid mass production of selected cultivars in a small space, and for an indefinite time period. The tissue-cultureraised products are robust, disease-free, and have desirable characteristics. The aim of this chapter is to compile information on tissue culture studies on Juglans regia with a special focus on the latest developments in the field. The chapter covers various pathways employed for the in vitro propagation of walnut, hardening, and acclimatization of tissue culture raised plantlets to ensure better quality, quantity, and sustainability of walnut trees to meet the demand of the growing global population. 

Keywords: Callus Culture, Embryo Culture, Hardening, In vitro Rooting, Juglans regia, Nodal Explant Culture, Somatic Embryos, Walnut.