Vaporizable material is supported within a vessel to promote contact of an introduced gas with the vaporizable material, and produce a product gas including vaporized material. The present invention is also directed to a coating composition comprising the cyclic guanidine. The invention further relates to methods for producing a squash plant containing in its genetic material one or more transgenes and to the transgenic plants produced by that method and to methods for producing other inbred squash lines derived from the inbred 835.