The Good, the Bad and the Best Tomato Plants
The plot could be right out of a spaghetti western: bad elements come to town, plants are killed, big showdown, local farmer saves crops with help of the good guys.
The teamwork of University of Guam researchers, extension agents and local farmers averted a tomato tragedy on the island. The saga began during the 2011 spring planting, Watson and neighboring
farmers John Mesa and Mark Pieper began noticing severe leaf curling and stunted growth of young plants of the cherry tomato variety Season Red. By October, Watson’s tomato crop was a total loss and the disease had spread to Vicente Valasquez’s farm. Jesse Bamba collected samples for analysis by Extension Plant Pathologist Dr. Bob Schlub.
The culprit is a Begomovirus that attacks tomatoes and other plants which is spread by a small insect, Bemisia tabaci or white fly. Schlub says, “As a result of several conversations with Dr. George Wall, we concluded that Dr. Wall may have discovered the virus years earlier at Mr. Watson’s farm. This was partially confirmed when Agdia Diagnostics compared results from tissue samples collected by Mr. Bamba in 2011 to those from Dr. Wall in 2007.”
Several control strategies were recommended to the farmers by extension agents Bob Schlub, Jesse Bamba and Roger Brown including the growing of seedlings under netting to exclude vectors, not transporting plants from infected areas, allowing infected fields to be rotated out of tomatoes for 120 days with plants that do not promote buildup of white fly populations, and growing Begomovirus resistant tomatoes.
Following recommendations from extension personnel, Mr. Watson decided to switch varieties and grow TYLCV resistant varieties from Lefroy Valley vegetable seed company. Mr. Watson discovered that the varieties Carmine, Felicity and Martyni did well on Guam. Five weeks after transplanting, all three varieties set fruit and were asymptomatic. During this period, Valasquez replanted his virus-infected field with Season Red plants and experienced a total crop failure.
“It is always rewarding to work with Bernard. He is a passionate farmer who wants to take advantage of research and modern diagnostic tools to make informed decisions about his crops and he allows us complete access to his fields to monitor and assist,” says Bamba.
Researchers, extension agents and farmers working together make a real difference for the island of Guam.
Funded by USDA Western IPM, UOG Cooperative Extension, WPTRC