Project Number: 5347-22620-021-07
Project Type: Nonfunded Cooperative Agreement

Start Date: Feb 01, 2011
End Date: Jan 31, 2016

Objective:
The whitefly Bemisia tabaci is one of the most important pests of agricultural and ornamental crops worldwide, causing direct feeding damage, negatively affecting post-harvest of numerous crops, and transmitting devastating plant viral diseases. B. tabaci feeds exclusively on plant sap, and therefore has evolved a unique digestive system that handles excess dietary fluid and maintains osmotic pressure. Previously, we characterized an aquaporin protein from B. tabaci (BtAQP1) that functions as a water channel protein to transport water through the specialized digestive tract. The objective of the proposed cooperative research is to test novel antagonists specifically developed to target aquaporins and ascertain if these agents interfere with water permeability of the BtAQP1 and thus negatively impact B. tabaci. Compounds optimized for efficacy and specificity against insect aquaporin targets represent a novel insecticidal approach for insect pest control.

Approach:
We propose to first evaluate agents that are fast unidirectional blockers of water flux as well as slower bidirectional blockers against BtAQP1 produced using a frog oocyte expression system. Any compounds found to be effective on the BtAQP1 in the oocyte expression system, would then be tested on the developing and adult whiteflies. Compounds will be tested against B. tabaci by direct application and through oral feeding, using both plants and artificial feeding systems. For promising compounds, we will develop a chemical library of analogs around the active structure, and improve potency for selective channel block and whitefly efficacy.