NMC issues update on new veggie pests
Scientists from the Northern Marianas College CNMI Cooperative Research, Extension and Education Service (NMC-CNMI CREES) have new information on the recently discovered “two-lined cucumber beetle” (2LCB) and the two species of Sweet Potato Weevils.
NMC CREES staff has surveyed many Tinian farms looking for the new beetle on commercial cucurbit crops. Most recently, Arnold Route reported an isolated detection of the 2LCB on a mature pumpkin plant.
This is the first, and only report of finding the potential pest on a plant of commercial value. All previous collections of the 2LCB were found on the small “patola” or wild luffa squash, where it caused heavy damage to the foliage.
The 2LCB has also been found on Rota. Alejandro Badilles, Rota’s IPM team coordinator, discovered the 2LCB on the wild patola gourd, the same as on Tinian. The beetle has only been found on the wild patola, and fortunately has not spread to other commercial crops.
No signs of this new beetle on any crops or wild patola gourds can be found on Saipan. Management recommendations for the new pest beetle will be announced after the identification and life cycle has been examined and understood.
After the first discovery of the new species, the West Indian Sweet Potato Weevil (WISPW) Euscepes postfacsiatus, in Rota, NMC’s IPM staff has been investigating pest damage on the sweet potato crops on Tinian and Saipan.
The teams report finding the new weevil alongside the “old” sweet potato weevil, Cylas formicarius, on all almost all sweet potato fields on the three main islands of the CNMI. This has become a major problem since the pest weevil adds to existing problems that farmers face.
The two weevils cause similar damage to the potato tubers and stems, causing quality loss and actual destruction of the sweet potato crop.
The Pacific Basin Agriculture Research Center, in Hilo, Hawaii, is starting a new management research project on the WISPW. IPM coordinator Dr. Lee Eavy is sending specimens of the new weevil to PBARC as part of the new cooperative ventures they are working to establish.
The CREES IPM team recommends an integrated approach for sweet potato weevil management, which includes:
• Traps baited with sex scent lures to collect and kill male weevils;
• A “dipping” treatment of new plants before planting;
• Clearing the perimeters of sweet potato patches to kill the wild alternate host morning glory vines;
• The complete removal of all old sweet potato crops from the fields as soon as they are harvested; and
• Crop rotations, which drive out the weevils and starve them for lack of food. NMC scientists have developed new methods for sampling sweet potato vines for these two weevils, and continue to search the sweet potato fields and rear specimens from sweet potato tubers in the laboratory to collect more specimens of the new weevil.
Dr. Eavy is requesting farmers and the general public to capture as many specimens as possible, for examination and identification. Please bring specimens of this beetle or sweet potato weevil to the Agriculture Research Lab at NMC’s As Terlaje campus, the “Bug Doctor” booth at the Saturday morning Sabalu fresh market, or to Rota and Tinian Agriculture Extension Agents.
