Vegetative propagation

Vegetative propagation is asexual reproduction of a plant from vegetative parts, such as a plant stem, leaf or root. In a common artificial example, a detached plant cutting forms new adventitious roots and becomes an independent plant. No union of gametes is needed to produce this descendant. Plant clone describes the resulting lineage; vegetative propagation describes the process.

A soft shoot presents a useful physiological problem: its leaves can lose water before it has a functioning root system. The RHS procedure therefore uses young non-flowering shoots, moist growing medium and a humid enclosure while rooting occurs, followed by gradual exposure to less humid conditions. This is a practical application of the balance between water supply and transpiration, rather than a guarantee that every detached plant stem can regenerate.^[ref]

An experimental rooting comparison should specify both the denominator and the endpoint. If six of ten plant cuttings produce visible adventitious roots by a stated day, the observed rooting fraction is $6/10=0.6$. That hypothetical result measures this protocol and starting material; it is neither a universal property of vegetative propagation nor proof that the remaining four plant cuttings are dead.

A plant clone is a lineage of plants descended from one founder by asexual reproduction. Vegetative propagation, for example rooting several plant cuttings from one stock plant, can multiply a selected genotype while avoiding the reshuffling associated with ordinary sexual reproduction. This is why such methods are useful for maintaining a named cultivar that does not reproduce its characteristics reliably from seeds.^[ref]

A plant clone is defined by descent, not by identical appearance. Its members can experience different light, water or nutrient conditions, and somatic mutations can arise during growth. Shared ancestry consequently does not imply that every phenotype or every later DNA sequence must remain identical.

For an illustrative experiment, divide rooted plant cuttings from the same founder between brighter and dimmer conditions while keeping other conditions comparable. Differences in leaf size need not establish a difference in inherited genotype: the design deliberately holds ancestry relatively constant while changing the environment. Repeating this across several distinct plant clones can test whether different genotypes respond differently, an example of genotype-environment interaction.