Walnut Genotypes for High Density Orchards

The aim of this review is to check the possibilities and circumstances regarding how create a high-density Persian walnut orchard. Increasing yields, decreasing tree size, limiting juveniles, lowering total costs are most important objectives breeders horticulturists. Reducing size trees can increase yield. Breeding programs in several countries have led production dwarf rootstocks. For example, Daixiang Daihui China, Alvand Iran, Fernette France all novel-bred dwarfing These precocious walnuts considered be rare resource study precociousness as well juvenile flowering mechanisms. Moreover, they play potential role breeding modifying cultivars by genetic engineering, through ameliorating programs. CRISPR (clustered regularly interspaced short palindromic repeat) technique used improve walnuts, which will near future.