Hybrid Rice Seedlings Grown in Greenhouses

Hand Transplanting Hybrid Rice Seedlings from Greenhouses to Field

Evaluating Growth

Hybrid Varieties Ready for Harvest

Hybrid rice, produced from the first generation (F₁) of seeds between a cross of two genetically dissimilar pure line (inbred) parents, represents a relatively new option for Louisiana farmers. Commercial hybrids typically yield 10-20% more than the best inbreds grown under similar conditions believed to be the result of hybrid vigor or heterosis from crossing the two parents. Research goals of the Hybrid Rice program at the H. Rouse Caffey Rice Research Station include: 1) development of male-sterile lines (cytoplasmic A or environmental sensitive S), restorer (R) and maintainer (B) lines adapted to the southern U.S. environmental conditions; 2) identifying elite cross combinations through extensive test-crossing; and 3) exploring the feasibility of economical hybrid seed production.

Several Louisiana experimental hybrids have shown high yield potential and good milling performance in multi-location trials in in Acadia, Evangeline, Jefferson Davis, Lake Arthur, and H. Rouse Caffey Rice Research Station locations. Selected hybrids in inoculated plots showed good to moderate levels of resistance against leaf blast, sheath blight, and bacterial panicle blight diseases in Evangeline and Jefferson Davis parishes. During Observational Trials, several new hybrid combinations produced high grain and head rice yields, and low chalk. One Clearfield and one conventional long-grain hybrids produced high grain yields across the multi-location Uniform Regional Rice Nursery in five southern states. Additional nurseries at the Rice Station included numerous entries for male-sterile S line, R line, and B line development. DNA technology was used to identify and validate new candidate markers associated with low chalk specific to Louisiana varieties and elite breeding germplasm.

To complement the existing Clearfield herbicide technology, the H. Rouse Caffey Rice Research Station is currently developing inbred and hybrid varieties that are resistant to the quizalofop-p-butyl (Provisia^TM) herbicide for control of grassy weeds. Several new male-sterile, restorer, and maintainer lines in field trials showed high levels of resistance to Provisia along with improved agronomic characteristics. New candidate Provisia hybrids have shown high yield potential in Observational Trials at the H. Rouse Caffey Rice Research Station.

Sheath blight disease caused by the fungus Rhizoctonia solani is a major constraint for high grain and milling yields. Our goal is to develop sheath blight-resistant germplasm by traditional crossing and selection in conjunction with DNA marker technology. Many crosses for sheath blight resistance are made and evaluated each year. In addition, F₁ plants, backcross (BC) populations, and space-planted F₂ populations are evaluated. DNA technology is used to identify and advance elite lines with moderate to high levels of resistance to sheath blight.

Drone technology at the H. Rouse Caffey Rice Research Station is being evaluated as a tool to maximize hybrid seed production and quantify stand establishment in small research plots.

For more information, please contact Dr. James Oard.