Non-recurrent Type

As mentioned earlier it refers to embryo development in reduced embryo sacs. The mechanisms identified for such cases are:

• Reduced Pseudogamy: The reduced egg develops in a pseudogamous, and parthenogenic manner. The pollen tube enters normally but the male gamete fails to fuse with the egg and disintegrates in the cytoplasm of egg.
• Reduced Parthenogenesis: Embryo development is accomplished by heat or cold treatment.
• Androgenesis: The egg nucleus degenerates, the sperm nucleus functions in the cytoplasm of the egg and produces the embryo.