A developmental study on anther wall and pollen in Mangifera indica L. var. Beneshan (Anacardiaceae)

Abstract

The Anacardiaceae is a well-recognized family consists of an economically important nut and fruit crops. In this family, the studies on both anther wall and pollen development are very limited. The present paper describes a comparative study on the development of both anther wall and pollen of male and hermaphrodite flower buds of Mangifera indica L. var. Beneshan by combining light (LM), fluorescence (FM) and transmission electron microscopy (TEM). Moreover, a description of the anatomy of the sterile staminodes of male flower buds also provided. Our study showed that the (1) anther wall contains two cell thick middle layers, (2) the presence of a secretory type tapetum, (3) tapetum cells contain large and uninucleate nucleus, (4) the presence of simultaneous cytokinesis (5) haploid microspores arranged in tetrahedral tetrads (6) the pollen grains shed at two-celled stage, (7) druse type calcium oxalate (CaOx) crystals were found in idioblast cells of anther connective tissue (8) both the anther wall and pollen developmental events in male and hermaphrodite flowers were found to be similar and (9) staminodes have failed to differentiate and form pollen grains. Overall, the study confirms the placement of M. indica in the tribe Anacardieae of Anacardiaceae and also provides information on correlation of the microspore development stage with flower bud and anther developmental stage for the establishment of in vitro culture for the production of doubled haploids in mango.