HomeInternational Rice Research Notesvol. 25 no. 3 (2000)

Molecular Tools for Zygotic Embryo Ablation in Rice

A. Kathiresan | G S. Khush | J. Bennett

Discipline: Agriculture, Crop Science



One of the serious constraints to hybrid rice technology adoption is the high cost of seed production. The dependence of hybrid seed production on parental crosses and the loss of heterotic vigor in successive generations can be eliminated if hybrid seeds can be multiplied asexually. Apomixis is an asexual means of seed production that occurs in several plant species including wild relatives of cereals such as maize, pearl millet, and wheat (Khush et al 1994). Careful searches made in rice germplasm so far have not revealed any occurrence of apomixis in rice (Rutger 1992, Brar et al 1995). Although several apomictic mechanisms exist, apomixis in principle is achieved by (1) cessation of steps leading to zygotic embryo development and (2) induction of an asexual embryo in nucellar tissue. Our goal is to develop apomictic rice through genetic engineering. In this note, we report the strategy and progress made in generating tools for arresting sexual embryo development.