Development of maize caryopses resulting from in-vitro pollination.

Intact maize (Zea mays L.) ovaries were excised from unpollinated ears (pistillate inflorescences of field-grown plants and placed on defined, agar-based media in Petri dishes. Application of pollen to the end of silks (styles) positioned outside the Petri dish resulted in fertilization of 46% of the ovaries. The extent of subsequent kernel (caryopsis) development varied. After 40 days some kernels had only embryo development while others had embryo and variable endosperm development. About 5% of the initial ovaries developed into normal kernels; 60% of the kernels with some endosperm germinated under laboratory conditions, and 70% of the embryos excised from the embryo-only kernels germinated on culture media.