xenia and metaxenia terms are related with

1. pollen culture
2. xylem and phloem
3. pollen effect on endosperm only
4. pollen effect on endosperm and fruits

Xeniain plants is the effect of pollen on seeds and fruit.The term was coined in 1881 by the botanistWilhelm Olbers Focketo refer to effects on maternal tissues, including the seed coat and pericarp, but at that timeendospermwas also thought to be a maternal tissue, and the term became closely associated with endosperm effects.The termmetaxeniawas later coined and is still sometimes used to describe the effects on purely maternal tissues.