The studies of generative structures and their idioblasts in Mazafati cultivar of Phoenix dactylifera L. (Arecaceae)

Mazafati cultivar of date palm (Phoenix dactylifera L.) is one of the most important cultivars cultivated in Kerman province particularly in Bam. Studies of floral ontogenesis are key elements for understanding sex determination and its control, evolutionary relationships within the palm family and with respect to other monocot groups, as well as in angiosperms as a whole. Development of generative structures was studied using cyto-histological methods. Flowering behavior within single shoots is Pleonanthy in which flowering branches appear in leaves axils and continue to be produced as the palm continues its extension. Initial developmental stages occur while spathes are hided in leaf axil. Female spathes are smaller and have brighter flowers compared to male ones. Flowers contain three sepals and three petals that are distinguishable in shape. In staminate flowers, a rudimentary gynoecium and in pistillate flowers, a sterile androecium was observed suggesting a possible evolutionary movement from an ancestral hermaphrodite flower to the situation of unisexuality and dioecy. Secretary tapetum is degenerated during pollen differentiation. Middle layer degeneration occurs after pollen formation and during its development, thus, somewhat later compared to polygonum type. Phenolic idioplasts are observed in anther parachyma especially in connective location. Their size and number increase during maturation, extended to dehiscence place. Pollen grains are prolate, spindle shape and monocolpate. The gynocium is tricarpellate and apocarpous that only one carpel develops and the rudiments of other two may be observed with fruit. Anatropous ovule contains two integuments, sclereids and idioplasts containing calcium oxalates crystals (raphids) and phenolic compounds.