Abstract: A method for regulating expression of a virulence gene of Agrobacterium is described. The method comprises the steps of stimulating cereal cells, such as sorghum, so as to produce an active, typically phenolic, compound and exposing the Agrobacterium to this compound. The compound induces expression of the virulence gene of the Agrobacterium, effecting T-DNA transfer from the Agrobacterium to the cereal cells, which are thereby transformed.

Abstract: A process for the production and maintenance of pluripotent and/or totipotent progenitor cereal cells from undifferentiated callus cells is described. Production of the progenitor cells takes place via direct organogenesis on a medium containing at least one auxin and at least one cytokinin. For example, the auxin may be 2,4-dichlorophenoxyacetic acid, indole-3-acetic acid, picloran, naphthelenacetic acid, indole-3-propionic acid, indole-3-butyric acid, phenyl acetic acid, benzofuran-3-acetic acid or phenyl butyric acid, and the cytokinin may be benzyl amino purine, benzyladenine, thidiazuron, zeatin, isopentyladenine, trans-zeatin or dimethylallyladenine. Processes for transformation of the undifferentiated callus cells and/or the progenitor cereal cells are also described. Typical cereal cells are sorghum, maize, wheat, barley, millet, rye, canola, alfalfa, triticale and rice.

Abstract: A method for regulating expression of a virulence gene of Agrobacterium is described. The method comprises the steps of stimulating cereal cells, such as sorghum, so as to produce an active, typically phenolic, compound and exposing the Agrobacterium to this compound. The compound induces expression of the virulence gene of the Agrobacterium, effecting T-DNA transfer from the Agrobacterium to the cereal cells, which are thereby transformed.

Abstract: Disclosed are polynucleotides encoding a pesticidal fusion polypeptide comprising (i) a toxin domain; and (ii) a heterologous binding domain capable of binding non-specifically to a cell membrane without disrupting that membrane. Preferably the toxin domain is derived from a Bacillus thuringiensis cry toxin (e.g. CryIA (b) or (c)) and the binding domain is derived from a lectin (e.g. ricin toxin B chain). The use of such fusions may help to inhibit the acquisition of resistance in a pest population treated with the polypeptide. A further aspect of the invention is a method of assessing the toxicity of a polypeptide to a pest species by expressing a nucleic acid encoding said polypeptide in a host cell from that species, observing the viability of the cell and correlating the results of the observation with the toxicity of the polypeptide, wherein the viability is determined by assessing esterase activity or membrane.