Location: Invasive Species and Pollinator Health
Project Number: 2030-22000-033-030-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 26, 2024
End Date: Nov 29, 2024
Objective:
1. Sample crystalline and slenderleaf ice plants, Mesembryanthemum spp., in coastal western South Africa, and collect candidate biological control agents. 2. Sample related plants in South Africa to examine field host range of candidate agents of ice plants. 3. Conduct laboratory studies to examine ice plant genetic orgin and candidate agent biology and efficacy. 4. Upon request, ship one or more candidate agents to the USDA-ARS ISPH Quarantine Laboratory in Albany, California, for further evaluation.
Approach:
Under Objective 1, the Cooperator, two Masters students and a technician will visit at least 12 sites in western coastal South Africa to collect the stem-boring weevil Lixus carinerostris, a candidate biological control agent for crystalline ice plant (Cryophytum crystallinum) that was prioritized for further study on the basis of prior research. The Cooperator and staff will also visit at least nine sites with populations of slenderleaf ice plant (Mesembryanthemum nodiflorum) to collect moth larvae and other potential candidate agents targeting this ice plant. Under Objective 2, the Masters degree students and a technician in South Africa will conduct field studies to obtain further information on the biology, host range and potential efficacy of candidate agents. On crystalline ice plant, a Masters student will attempt to collect the Lixus carinerostris weevil from six other members of the genus Cryophytum to determine its host range. Under Objective 3, the Cooperator, students and technician will rear the L. carinerostris weevil on to gain a better understanding of its biology and efficacy. Candidate agents of slenderleaf ice plant will also be reared. An efficacy test will be conducted in a greenhouse or shadehouse for the weevil on crystalline ice plant and possibly for a candidate agent on slenderleaf ice plant. Under Objective 4, the ARS PI will request at least two shipments of the Lixus carinerostris weevil. If a promising candidate agent targeting slenderleaf ice plant is found, the ARS PI will request at least one shipment of that agent.
