As a plant breeder, one of the cool things we get to do is observe the diversity that arises from a single cross. In some cases, the diversity shows up in the first generation (F1), while in other cases, the first set of offspring need to have sex with each other for the diversity in the offspring to reveal itself (Mendelian genetics). Fortunately, with agaves, we can see quite a bit of diversity in the F1 populations.
Below is a cross we call Agave x amourifolia, which is our cross of Agave ovatifolia, pseudoferox (salmiana var. ferox of Hort.), and lophantha. Here are three of our selected seedlings from that cross.
Plant #1 below is showing the large size of Agave x pseudoferox and the color of Agave ovatifolia (blue), with little visible influence of the narrow leaf, yellow-centered Agave lophantha.
Plant #2 below show more color influence from Agave x pseudoferox, but with the compact form influence of Agave ovatifolia.
Plant #3 below shows equal parts Agave x pseudoferox and ovatifolia, but also, what appears some leaf narrowing we would expect from Agave lophantha.
Below is Agave x flexiferox, created from a cross of the small Agave flexispina x the giant pseudoferox (salmiana var. ferox (Hort.). Plant #1 shows the small size of Agave flexispina, with the greenish coloration of Agave x pseudoferox.
Below, Agave x flexiferox ‘Megalodon’ shows the larger size and overall coloration from Agave x pseudoferox, with some added blue tones from Agave flexispina.
Below is Agave x victoferox, a cross of Agave victoriae-reginae x pseudoferox. Plant #1 below shows the form and size of Agave victoriae-reginae with the color of Agave x psedoferox.
Hybrid #2 below shows the teeth from Agave x psedoferox (victoriae-reginae has no teeth), and a size intermediate between the two parents.
Hybrid #3 below shows a larger size and more teeth due to more genes from Agave x pseudoferox. The teeth are much smaller because of the Agave victoriae-reginae genes. The splendid compact form also comes from the Agave x victoriae-reginae parent. This cross almost resembles the Northern Mexican Agave montana.
We hope this gives you a small peek into the world of plant breeding and the subsequent evaluation and selection process.
It would be useful to provide two brief sentences describing what is done to “cross” these plants, and how you assure that the cross is exactly and only between the plants mentioned.
To make a cross, we remove the pollen from one parent and place it on the stigma of the other plant. Before doing so, we remove the anthers/pollen from the flowers of the female plant to be pollinated.