What about Tripsicum?

One of my research projects is to look at maize storage proteins (aka zeins) in a variety of modern corn varieties, landraces (older varieties), and teosinte (a maize progenitor in the same genus). See my post Teosintes are a puzzlebox of genes for more info.
Now, I’m adding another angle – Tripsicum ! I was talking to Sue Duvick of the USDA about my project (since I am using her lab’s HPLC after all) and she told me about her work making crosses between maize and Tripsicum in a search for improved grain quality.
Members of the Tripsicum genus are closely related to members of Zea genus. They’re all part of the tribe Maydeae in the subfamily Panicoideae. It’s such an important source of germplasm that the USDA ARS has been collecting Tripsicum samples along with maize and teosinte for safekeeping.
Sue was kind enough to provide me with seed samples to analyze. From the left is Tripsicum seed and seed capsules, a Tripsium and maize F1 hybrid, and two set of seeds that are mostly maize but derived from the F1. For comparison, on the bottom are teosinte and B73 (a typical maize inbred). Adult Tripsicum is a bunched perrenial grass, as you can see from the photo.
For some very interesting info on cross-generic hybrids, see the discussion at GardenWeb. There is even some specific discussion of maize x Tripsicum crosses. For example: the cross is “very easy if you carefully remove the husks, shorten the silks to about 1.5 inches, pollinate with Tripsacum pollen, then wrap the ears with paper while the seeds develop. The problem in the cross is that Tripsacum pollen doesn’t have enough “stuff” to grow pollen tubes the full length of the Maize ear. Shortening the silks solves this problem. …other results indicate that the best way to breed Tripsacum traits (such as pest resistance) into Maize is by first crossing Tripsacum with Zea diploperennis, then crossing these hybrids onto Maize.”
Gamma grass image from Sticks and Stones Nursery. Original Caption: “EASTERN GAMMA GRASS (Tripsicum) – Warm-season, rhizomatous bunch perennial grass. Spreads slowly. Height 5′-9′. Site-open, moist, well drained. Choice grazing for livestock and wildlife. Used for hay, cover/nesting, and erosion control. Hardy in zones 5 -10. American native.”
Seeds image taken by me. Grid is 0.5 cm.

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