Location: Crop Genetics and Breeding Research
Project Number: 6048-21000-027-000-D
Project Type: In-House Appropriated
Start Date: Dec 21, 2017
End Date: Mar 24, 2019
Objective:
1. Improve the productivity, quality, and persistence of warm-season grasses grown for forages, bioenergy, and turf by enhancing germplasm to increase stress tolerance under a variety of environmental conditions and improving tools that will efficiently assess forage quality.
2. Develop improved production strategies that include warm-season grasses, legumes, and winter cover crops to meet life-cycle objectives for feedstock production and quality, carbon sequestration, and greenhouse gas emission reductions for the Southeast regional conditions.
Approach:
Objective 1: Three bermudagrass populations with desirable traits for forage, good seed production, and synchronous pollination will be used in a system of recombinant recurrent selection to develop a uniform, highly productive seeded bermudagrass for forage and/or turf. Multiple cycles of selection and crossing will be done to create populations that will be tested in multiple replicates at different locations. In napiergrass, a similar approach will be developed to develop vegetatively propagated high yield, disease resistant genotypes for multiple location testing and eventual release. Also for napiergrass, sequence data generated from genomic DNA from the cultivar Merkeron will be used to mine single sequence repeat (SSRs) markers and match them with genotypic traits of interest as marker assisted selection. Similarly, SSR markers will be developed for salt tolerance in segregating populations of seashore paspalum. Near infrared spectroscopy (NIRS) will be developed as a tool to screen for forage and biomass quality from available genotypes with diverse cell wall characteristics. Non-grain sorghum germplasm from multiple sources will be evaluated in replicated trials in the field and greenhouse for susceptibility to anthracnose, root-knot nematodes, and fall armyworm. Selected lines will be used as parents to test hybrids for biotic stress and yield characteristics for eventual public release. Linkage maps will be developed for markers of biotic traits.
Objective 2: Replicated tests will be performed to determine appropriate nitrogen-fixing winter legume cover crops (clovers and alfalfa) for use in forage bermudagrass (Tifton 85, Russell) to reduce fertilizer applications and improve forage quality. Similar tests will be conducted for efficient production of biomass from energy cane, napiergrass and biomass sorghum (rotated with traditional row crops). Winter cover crops (lupine, clover, others) will be tested against inorganic and unfertilized controls to determine efficient ways of reducing inorganic fertilizer use. These replicated tests will be conducted at multiple sites. Production systems will be tested to determine water and nutrient requirements for maximum biomass yields of napiergrass using a replicated split block design with three irrigation rates and six fertilizer treatments. In collaboration with other research units, greenhouse gas emission comparisons will be determined for the cropping systems of biomass crops as well as for forage bermudagrass cultivars compared to traditional row crops.
