Xenia (plants)

The term was coined in 1881 by the botanist Wilhelm Olbers Focke to refer to effects on maternal tissues, including the seed coat and pericarp, but at that time endosperm was also thought to be a maternal tissue, and the term became closely associated with endosperm effects.

[1] One of the most familiar examples of xenia is the different colours that can be produced in maize (Zea mays) by assortment of alleles via individual pollen grains.

The endosperm tissue, which makes up most of the bulk of a maize seed, is not produced by the mother plant, but is the product of fertilization, and genetic factors carried by the pollen affect its colour.

[3] Because there is concern about pollen from genetically modified (GM) crops, male-sterile forms are being considered, particularly of maize.

In some cases, a xenia effect due to the genetic difference between the two strains has been observed that increases grain yield, and could make it financially viable to grow the male-sterile plants in such a mixture.