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- As difficult as water cutbacks are, they pale in comparison to the biggest challenge California cotton has faced in its 100-year history — Fusarium Race 4.
Aerial view of a field infected with Race 4.
The battle looked like it suffered a major setback when USDA-ARS pulled out of the Cotton Research Station in Shafter a couple of years ago. There were two scientists there working almost exclusively on Race 4.
Fortunately, one of those two scientists continues to research germplasm for FOV resistant varieties.
USDA research geneticist Mauricio Ulloa was moved from Shafter to Lubbock, Texas, where his primary research responsibilities are developing drought and heat tolerant cotton germplasm.
“Fortunately,” said Hutmacher, “USDA-ARS administrators recognized the importance of Mauricio’s work from Shafter to allow him to continue his Race 4 work.”
“Mauricio’s background in molecular genetics, and the fact he has been working along with the rest of us for 10 years on the problem is a big plus.”
Ulloa’s goal is to provide Race 4 resistant germplasm to commercial plant breeders to develop new varieties.
Another key person in finding solutions to Race 4 is UC Davis plant pathologist Mike Davis. He was the first to identify it. He remains active in the team effort and has picked up some of the research the other Shafter scientist was doing. Rebecca Bennett has been working on seed treatments for Fusarium, but she is no longer researching that area in her new post in Arkansas.
What do growers do in the meantime until more resistant varieties are released?
First is to identify it. If Race 4 is confirmed, growers should avoid moving soil and water from a contaminated field to a clean field. Hutmacher said it is a good idea to clearly mark contamination areas and change cultivation practices to avoid it.
Davis and Bennett have done enough research to verify that
Vapam spot treatments offer some benefits in knocking down inoculum populations. “It will not eradicate Race 4. Nothing will at this point,” he added.
“We continue to look at seed treatments, but so far they offer little value,” he said. There are biological materials that reportedly change soil conditions to suppress inoculum levels and Hutmacher will continue to look at those.