| [Image: Dr. Chuck Rush Receiving an award] |
|
|
When he came to Louisiana in 1970, Dr. Chuck Rush started his LSU AgCenter career conducting rice research, and 39 years later he’s still searching for answers.
Rush began his career carrying out rice disease surveys and developing a research program to study and control seedling diseases, rice sheath blight, blast, stem rot, brown spot and Cercospora leaf spot diseases. He’s still moving in the direction of finding ways to help rice producers control diseases.
"Disease is still the most uncontrolled constraint on rice," Rush said.
An Arizona native, Rush grew up on a dairy and cotton farm. Then it was off to college where he received his bachelor’s and master’s degrees from the University of Arizona and his doctoral degree from North Carolina State University.
But his next stop brought him to LSU, where he’s been ever since.
"When I started, rice plots at the station were hand-planted," Rush said. "In those days, the seed was in an envelope and planted with a hand-pushed drop planter. I had 4 acres of plots – most planted by hand, although yield plots were planted with a drill."
Rice seed was treated with seed-protected fungicides. Then stands in the plots – hundreds of them – were counted by hand.
"Most of our work was done on grant funds from fungicide companies," Rush said. "Nothing was labeled then for diseases except seed protectants. We worked with DuPont to get Benlate labeled for rice and made progress on getting other chemicals labeled."
By 1984 he had spent 12 years running the fungicide testing program that he turned over to Dr. Don Groth. During his time on the program, Rush was the first to test all the seed-treatment fungicides labeled for rice.
After Groth’s arrival, Rush began working on breeding for disease resistance, especially for resistance to sheath blight.
In another first, Rush was the original researcher to report eight diseases in Louisiana rice – sheath rot, leaf scald, bacterial sheath rot and panicle blight, white leaf streak, crown sheath rot, sheath blotch, feeder-root necrosis and false smut. He and his graduate students elucidated the importance of leaf surface interactions between host and pathogen regarding Rhizoctonia solani, the cause of sheath blight.
"We were breeding for sheath blight resistance," he said. "We inoculated F2 generations, then sorted for resistance and agronomic characteristics in next generations."
In the heyday, Rush had 600 crosses and thousands of panicle tests every year. Many trials were with double plots – one inoculated and one control for comparison with commercial varieties.
Rush also pioneered the development in the South for rating scales for rice diseases. He studied the effect of cultural practices on controlling rice diseases and developed disease nurseries, information on fungicidal control of rice foliar diseases and new sources of disease resistance in rice technology to begin looking for natural mutations, particularly clonal variation for sheath blight resistance in rice varieties.
Now, over his career, Rush has identified more than 300 lines showing sheath blight resistance and high yield potential, and he’s turned them over to the breeding program at the Rice Research Station.
After a severe epidemic of panicle blight hit Louisiana in 1995, Rush began looking at microorganisms that live on rice leaves and began screening for the disease organism. He found two bacterial strains that cause panicle blight – one in grower fields the following year.
"Environmental conditions led to the development of epidemics in ’95, ’98 and 2000," he said. "The bacterial pathogen is seedborne and grows up with the foliage, particularly during periods of extremely high temperatures. We’ve had favorable weather since 2003, so we’ve had no epidemic since then. However, the disease occurs to some degree every year."
The main bacteria aren’t found in the soil. "If we can control it on the seed, we can control it," Rush said.
He’s been treating rice seed with antimicrobial chemicals, looking for rates that will control the disease and not damage the seed.
"In 2007, I had my last breeding test and turned over the program to Dr. Groth and Dr. Sha at the Rice Research Station," Rush said.
He’s finishing his career focusing on chemical control of bacteria on seed.
"We’ve named I don’t know how many new diseases in rice," Rush said of his career. "Seven or eight in the United States. And we’ve generated a bunch of lines with high levels of partial resistance."
Rush pointed out that total resistance isn’t necessary – just high levels of partial resistance.
"I’m hoping we’ll have a resistant sheath blight variety soon," he said. "I’m also hoping this will also give resistance to panicle blight. And it won’t be long before transgenic rice lines will have disease resistance."
Rush’s work in the LSU AgCenter includes publishing 294 articles, serving as major professor for 13 master’s degree and 14 doctoral degree students, being recognized with a variety of awards and capturing more than $1.6 million in grant funds.
"Chuck Rush has been a huge asset to the Louisiana rice industry during his tenure in the LSU AgCenter," said Dr. Steve Linscombe, AgCenter rice breeder and regional director. "He has developed a national and international reputation and is generally regarded as on of the premier rice pathologists in the world." –Rick Bogren
Checkoff funds for Dr. Chuck Rush’s 2007 research: $48,649