Lettuce variety 81-04 RZ

A method of vegetatively propagating a plant of lettuce variety 81-04 RZ comprising (a) collecting tissue capable of being propagated from a plant of lettuce 81-04 RZ, a sample of seed of said variety having been deposited under NCIMB Accession No. 42634, (b) cultivating the tissue to obtain proliferated shoots and rooting the proliferated shoots to obtain rooted plantlets, and (c) optionally growing plants from the rooted plantlet.

A method for producing a progeny plant of lettuce cultivar 81-04 RZ, comprising crossing a plant designated 81-04 RZ, representative seed which having been deposited under NCIMB Accession No. 42634, with itself or with another lettuce plant, harvesting the resultant seed, and growing said seed.

A method for producing a seed of a 81-04 RZ-derived lettuce plant comprising (a) crossing a plant of lettuce variety 81-04 RZ, a sample of seed of which having been deposited under NCIMB Accession No. 42634, with a second lettuce plant, and (b) whereby seed of a 81-04 RZ-derived lettuce plant forms.

A method of introducing at least one new trait into a plant of lettuce variety 81-04 RZ comprising:

• (a) crossing a plant of lettuce variety 81-04 RZ, a sample of seed of which having been deposited under NCIMB Accession No. 42634, with a second lettuce plant that comprises at least one new trait to produce progeny seed, (b) harvesting and planting the progeny seed to produce at least one progeny plant of a subsequent generation, wherein the progeny plant comprises the at least one new trait, (c) crossing the progeny plant with a plant of lettuce variety 81-04 RZ to produce backcross progeny seed, (d) harvesting and planting the backcross progeny seed to produce a backcross progeny plant, and (e) repeating steps (c) and (d) for at least three additional generations to produce a lettuce plant of variety 81-04 RZ comprising at least one new trait and otherwise all of the physiological and morphological characteristics of a plant of lettuce variety 81-04 RZ, when grown in the same environmental conditions.

A method of producing a plant of lettuce variety 81-04 RZ, comprising at least one new trait, the method comprising introducing a mutation or transgene conferring the at least one new trait into a plant of lettuce variety 81-04 RZ, wherein a sample of seed of said variety has been deposited under NCIMB Accession No. 42634.

A lettuce plant designated 81-04 RZ, representative seed of which having been deposited under NCIMB Accession No. 42634, further comprising a transgene.