Location: Crop Germplasm ResearchTitle: Registration of seed sterile, perennial Sorghum spp. [Sorghum bicolor (L.) Moench x S. halepense (L.) Pers.] hybrid 'PSH09TX15'
|JESSUP, RUSSELL - Texas A&M University|
|FOSTER, J. - Texas A&M Agrilife|
|HEITHOLT, J. - University Of Wyoming|
Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/2017
Publication Date: 8/1/2017
Citation: Jessup, R.W., Burson, B.L., Foster, J.L., Heitholt, J.J. 2017. Registration of seed sterile, perennial Sorghum spp. [Sorghum bicolor (L.) Moench x S. halepense (L.) Pers.] hybrid 'PSH09TX15'. Journal of Plant Registrations. 11:320-323.
Interpretive Summary: A unique perennial sorghum hybrid between a forage sorghum and Johnsongrass was selected, evaluated, and released. This grass is different because it rarely flowers. When it does flower, it is either early or late during the growing season and the few seed produced are not viable and do not germinate. This is important from both ecological and productivity perspectives. Since the grass does not produce seed, there is not a threat of it becoming an invasive species because of volunteer seed. It produces rhizomes but they are not as spreading or vigorous as Johnsongrass rhizomes. The grass will have to be vegetatively propagated by planting rhizomes to establish a stand. An advantage of the rhizomes is they make it possible for the hybrid to survive the winters in most of Texas and the hybrid will not need to be replaced. However, other forage sorghums are annuals and have to be replanted every year. Effective eradication methods have been established to eliminate the grass when a producer decides to plant another crop. Another advantage of the hybrid not flowering during the growing season is the plants do not use valuable nutrients and energy sources to produce seed heads and seed, but they are used to produce more vegetative growth. Consequently, the hybrid produces more forage than Johnsongrass and will produce as much forage as the highest yielding annual forage sorghums. As a high biomass genotype, PSH09X15 provides a perennial sorghum germplasm source suitable for being used as a hay, forage, and biofuel feedstock with risk of neither seed weed invasiveness nor hybridization with cultivated sorghums.
Technical Abstract: A novel, Perennial Sorghum spp. Hybrid (PSH) [Sorghum bicolor (L.) Moench x S. halepense (L.) Pers.] ('PSH09TX15'; PI ______) was identified that possessed complete seed sterility, only rare occurrences (< 0.1%) of flowering, and significantly higher mean leaf number per tiller than S. halepense. Initial collection of the hybrid was made in 2009, and subsequent evaluations were made in a collaborative effort between Texas A&M University, Texas A&M AgriLife Research, and the USDA-ARS. Winter survival of PSH09TX15 exceeded 98% at 3 locations in plant hardiness zones 9a, 8b, and 8a between 2012 and 2015 with no significant differences across locations. PSH09TX15 developed significantly higher leaf numbers per tiller (= 11) and lower in rhizome derived shoot (RDS) distances (-50%) than naturalized populations of S. halepense. PSH09TX15 produced annual biomass yields not significantly different than Dekalb Sudax (SX-17) forage sorghum across three seasons (2012 – 2014) at three locations (College Station, Beeville, Commerce) in Texas. Effective eradication protocols were identified for PSH09TX15 in order to enable crop rotations. As a high biomass genotype, PSH09X15 provides a perennial sorghum germplasm source suitable for utilization as a hay, forage, and biofuel feedstock with risk of neither seed weed invasiveness nor hybridization with cultivated S. bicolor.