Hi Wumei,

I see, nobody wants to touch the topic :-)

I am not sure, whether there are (commonly recognized legal and/or scientific) definitions of the terms you asked. I am also sure that many people use them interchangeably - which may lead to confusion and misunderstandings.

My take on the topic in the field of botany:

"Variations" (not to mix up with "varieties") are naturally occuring "subsets" of plants (true breeding mutations) in a species which differ somehow (mostly phenotypically) from the main population. While they are still able to interbreed with the main population they often dominate in their local (possibly separate) habitates. I guess that the borders to "sub-species" are liquid and that one could probably use the term "race", too.

"Cultivars" - are plants which have been selected or bred from wildtype plants or other cultivars and registered to be protected by intellectual property rights. I am not sure of the legal subtleties involved and the national systems will certainly differ. In my understanding "cultivar" and "variety" are synonyms - though, I could be wrong here.

"Genotype" refers to the genetic setup of each individual. If the cultivar is propagated clonally, then all individual will have the same genotyp (theoretically). Hence, in this case the cultivar has a defined genotype. If the cultivar is propagated sexually, then it will consist of a number of recombinant genotypes which are genetically similar, but not identical. Theoretically, different cultivars should be genetically more differentiated among each other and less differentiated within.

I am sure that this is not the whole picture - just my 2 cents for starters :-)

Regards,

Klaus

https://www.researchgate.net/post/Genotype_vs_cultivar-What_is_difference

Genotypic difference refers to the variability in the actual genetic make up of an organism,i.e.at molecular level. However, organisms of different genotypes can look similar from external look or phenotypically. for example, when two alleles occur together representing one trait, if one allele is completely dominant over the other allele, the recessive one can not express itself). In such a case the trait of the dominant expresses itself. As a result, two different genotypes can represent only one distinct variety.

Before the formal release as a variety or cultivar the genetic material is differentiated in form genotypes. Mor over cultivars are generally used in horticulture , e g. Apple cultivars , whereas varieties are used agricultural crops, e.g. wheat varieties.