The 105^th LSU AgCenter Rice Research Station Field Day was held on June 25. In spite of the threat of inclement weather, nearly 400 people turned out for the field day. The threat of rain caused the cancellation of the field tours, and the field tour speakers, instead, made their presentations indoors to the entire group. Tour speakers included scientists from the Rice Station, Dean Lee Research Station, Baton Rouge campus, University of Arkansas and Mississippi State University.

I made the first presentation and discussed the two recent rice varieties released from the LSU AgCenter. CL271 is a Clearfield medium-grain line with excellent yield and quality traits. The variety also has very good resistance to blast disease and straighthead disorder. CL-Jazzman is a Clearfield Jazzman line with very good yield and quality, as well as excellent aroma, cooking characteristics and blast resistance. I also discussed the work being conducted at the Rice Station to develop varieties for use with the Provisia rice production system. This is a BASF-developed herbicide-tolerant system that will provide post-emergence control of a broad range of grass weeds, including ALS-resistant grasses, weedy rice and red rice. The Provisia system will be used as a companion to the Clearfield system for rice, allowing growers to rotate herbicide sites of action for controlling target weeds. The Rice Station breeding program is developing varieties and hybrids adapted to Louisiana and the southern United States that can be used with this new weed control system. Dr. Xueyan Sha, who spent several years breeding new varieties at the Rice Station before assuming a similar position at the University of Arkansas two years ago, spoke next. His project in Arkansas is focused on developing both conventional and Clearfield medium- and semidwarf long-grain rice, as well as hybrid rice. He also discussed a conventional medium-grain experimental line, 13AR1021, which has performed very well in both the Uniform Regional Rice Nursery (URN) and the Arkansas Rice Performance Trial (ARPT) in the past two years. It matures six days earlier than Jupiter and has excellent yield potential, good milling and superior grain quality.

The next two speakers addressed rice weed control. Dr. Eric Webster discussed the strengths and weaknesses of the Provisia rice system. He stated that Provisia is an excellent grass control herbicide and will do a very good job controlling red rice. The herbicide will also provide control of weedy and red rice plants that have developed resistance to NewPath and Beyond herbicides through outcrossing with Clearfield rice varieties. He also discussed the research he and his group are conducting in managing red rice outcrosses with Clearfield rice and hybrid rice volunteers. They are evaluating a large number of experimental rice herbicides this year. He said an experimental herbicide, GWN 10235, has the best ducksalad control of any herbicide that he has ever evaluated. Dr. Bob Scott, University of Arkansas weed scientist, discussed the growing problem of herbicide resistance in Arkansas rice production. He said resistance to propanil first began to develop in that late 1990s. Since then, many fields, especially in northeast Arkansas, have been documented to contain propanil-resistant barnyardgrass. To combat this resistance, many consultants and growers began using POST-applied Facet in combination with propanil. Over time, this led to the development of barnyardgrass populations resistant to both propanil and Facet. In a recent survey conducted by the University of Arkansas, it was found that most populations of barnyardgrass resistant to Facet were also propanil-resistant. A small number of samples in that same survey were found to be ALS-resistant. This means that barnyardgrasses can tolerate most ALS-inhibiting herbicides, including NewPath, Beyond and Regiment. This has likely happened because of heavy reliance on NewPath in Clearfield systems and Regiment in conventional rice for barnyardgrass control. There have been some populations of barnyardgrass identified with resistance to propanil, NewPath and Facet, but, thankfully, only a few. In addition, two isolated populations of barnyardgrass were identified a few years ago with increased tolerance to Command. However, this was an area with a history of heavy Command use with little applied POST, and these are the only documented cases of Command resistance to date. While some of these resistance issues have been identified in Louisiana rice production, to date, the problem is much less severe than that being encountered in Arkansas.

The next talks were by Dr. Mike Stout and Dr. Jeff Gore, LSU AgCenter and Mississippi State entomologists, respectively. Dr. Stout discussed the eastern migration of the rice stalk borer. This insect was first found in Acadia Parish last year. As the insect slowly moves east across the rice growing region, it is still unclear how significant it might become. Dr. Gore discussed his rice insect research program at the Delta Research and Extension Center near Stoneville, Miss. He stated that in response to his research findings, the rice stink bug thresholds will soon be lowered in Mississippi.