Answer:
Non-nuclear inheritance
Beside the DNA present in the nucleus of cell, there is small portion of DNA that is present outside the nucleus within the cell, both plants and animal cells have this DNA in chloroplast and mitochondria respectively.
Mitochondria is the powerhouse of cell for its ability of energy production. It contains DNA that is called mitochondrial DNA (mtDNA), it is present in less amount as compared to the nuclear DNA. It is inherited maternally. mtDNA encodes genes for respiration, so in case of any disorder in mtDNA would result in disorder in mitochondrial function.
In plants, chloroplast is responsible for photosynthesis reaction. It also has its own DNA called chloroplast DNA (cpDNA). Its DNA encodes for certain pigments, so variation in cpDNA would result in alteration of pigments in the plants for example flower color or leaf color etc. Its inheritance is both paternally and maternally.