Arabidopsis Biological Resource Center

Ploidy: 2

Phenotype: Defective in sporocyte formation (resulting in the absence of microspores and megaspores) and anther wall formation; hypodermal cells of anthers at stage 2 enlarge and differentiate into archesporial cells normally; archesporial cells undergo periclinal divisions to form the primary parietal cell (PPC) layer and the primary sporogenous cell (PSC) layer at stage 3 anthers; PSCs do not form microsporocytes, becoming vacuolated at stage 4 anthers; parietal cells are also affected, because the PPCs go through only one division to give rise to two SPC layers that fail to divide further and differentiate; there is no endothecium or tapetum formation; anthers are composed of highly vacuolated parenchyma cells at anthesis; archesporial cells fail to elongate and differentiate into megasporocytes; nucellar development but not integument development is affected. Delayed plant senescence; sterile plants (complete male and female sterility); flowers have normal external morphology and the same number of organs as wild type, anthers are white with no pollen grains at anthesis during stage 13-14; carpels look morphologically normal but are infertile when pollinated with wild-type pollen.