Reproductive biology of calla lily

Zantedeschia (calla lily) cultivars are internationally popular floricultural crops. In this work, the megasporogenesis, microsporogenesis, and development of female and male gametophytes of Zantedeschia 'Majestic Red' were studied. Morphological characteristics, viability and germination characteristics of pollen were analyzed. The results showed that the ovule was anatropous, bi-integumented, and crassinucellar with integument tapeta. The megaspore mother cell meiosis formed a linear megaspore tetrad, with chalazal end megaspore developing into the embryo sac mother cell, which developed into a Polygonum-type embryo sac, and the other three megaspores degenerated. Each flower had two to three stamens with butterfly-shaped pollen sacs, each side with two small sporangia. The anther wall consisted of four layers: epidermis, endothecium, middle layers and deformation-type tapetum. Cytokinesis of the microspore mother cell during meiosis was of the simultaneous type. Microspore tetrads were mainly cruciform, and pollen grains were two-celled when shed. In the microspore tetrad, tapetum cells degraded in advance, so that the released small spores could not develop normally.