Location: Pest Management Research2012 Annual Report
1a. Objectives (from AD-416):
The galling moth Amblypalpis tamaricella is considered one of the best candidate agents for the control of saltcedar (Tamarix spp.). In Montana, the agent Diorhabda has not established, potentially due to high rates of predation by other organisms. The galling moth should be more resistant to predation as it spends much of its life inside the stem of saltcedar, where it damages branch growth. Successful rearing of the galling moth in confinement requires more research, as productivity (number of larvae or adults reared) has been low so far. In the USA quarantine, rearing has not yet been successful. The objective is to determine best rearing practices for this moth in confinement (which mimics conditions in USA quarantines) so that adequate numbers of moths can be utilized in host-specificity testing.
1b. Approach (from AD-416):
Moths will be collected at natural locations approximately 150-300 km away from the Kazakstan lab. New populations will also be identified and monitored in nearby western China. Tests will be conducted to determine the best method to develop moths to the next adult stage in both wild and confinement (laboratory) locations. Developed galls will be collected in the field and placed on new plants in both field and confinement conditions. Alternatively, recently emerged adults or eggs will be transferred to determine best transfer method. A weather monitor will be established at existing populations to correlate phenology with climatic data. Moths will be reared on both native saltcedar and accessions from the USA invasion. Main variables to be tested for rearing are temperature regime, humidity, size and age of host plant, amount of time that gall can be off tree, light regime, nectar source, number of moths and sex ratio for mating in confinement, size of confinement cage, etc.).
3. Progress Report:
The Institute of Zoology at Almaty, Kazakhstan, is continuing efforts of conducting studies to improve laboratory rearing of the tamarisk stem galling moth, Amblypalpis tamaricella. This involves studies that focus on environmental conditions needed by females moths for initiating egg laying on host plants, a major limitation that currently prevents successful lab rearing efforts (including the failed effort by Northern Plains Agricultural Research Laboratory in FY 2012). Other studies explore optimal and suboptimal environmental conditions for development, growth, and survival of this insect. Recent changes in Kazakhstan import regulations that were implemented in spring 2011 now prevent live USA tamarisk cuttings from being received when shipped by express carrier or mail, so studies on A. tamaricella performance on USA plant genotypes has been stalled. Efforts continue to set-up a common garden of Kazakhstan genotypes of tamarisk and non-target US species at the Kazakhstan Institute of Zoology (Almaty) so that future A. tamaricella host plant specificity tests under field conditions can be conducted. Efforts also continue for screening of other potential biological control agent species in case 1) A. tamaricella is unable to be reared under laboratory conditions, and 2) APHIS lifts its ban on permitting new biological control agents for tamarisk in the USA.