S. A. Stelting1,2, A. Sunna3, and C. R. Bunt4,5
1Department of Chemical and Process Engineering, University of Canterbury, Private Bag 4800, Christchurch, New Zealand, 2Present address: USDA, Wildlife Services, National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO 80521-2154, 3Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia, 4AgResearch, Private Bag 4749, Lincoln, New Zealand, 4Present address: Faculty of Agriculture and Life Sciences/Department of Agricultural Sciences, Lincoln University, New Zealand
Atrazine, a persistent and widely-used herbicide can be degraded by Pseudomonas sp. strain ADP. There is need for a room temperature stable formulation that might help to improve infield delivery and performance. Water activity throughout the study period remained constant (~1.0 aw) for all test samples. Immobilization of Pseudomonas sp. strain ADP onto zeolite using a xanthan gel maintained survival for at least 10 weeks at 25 ºC. Approximately 1 log loss by week 7 was observed when xanthan gel was not used. Pre-wetting the zeolite increased the time to 1 log loss to 9 weeks. Formulation, and to some extent moisture does influence the stability of Pseudomonas sp. strain ADP immobilized onto zeolite.