*WINNER* Ovipositional Preference of Silverleaf Whitefly on Benchmark Acylsugar Tomato Breeding Lines

Abstract

The silverleaf whitefly (SLW), Bemisia tabaci B biotype is an invasive hemipteran insect which can cause severe losses in tomatoes. Acylsugar (AS)-mediated insect resistance bred from the wild tomato, Solanum pennelli (SP) has been demonstrated to control a variety insect pests. Using SP LA716, the tomato breeding program at Cornell University produced new AS lines. The program recently transferred the CU071026, the first benchmark line, SP genomic regions controlling AS to a new background (CU17NBL) with superior horticultural traits. The goal of this project is to compare the SLW ovipositional preference between young seedlings of CU17NBL and CU071026, to insure that CU17NBL has at least the same resistance as CU071026. These lines were evaluated at the four true leaf stage in choice tests replicated in small greenhouse cage assays. Cages were infested with ~100 SLW and allowed to oviposit for two weeks. Four replicate assays were performed. Insect counts were recorded weekly at leaf positions one and four. Data was analyzed with a mixed model ANOVA. The week two counts revealed a significant ovipositional preference (P<0.0001) for the CU071026 line as it accumulated more than ten times the number of eggs as the CU17NBL. Similar trends were seen for the 1st/2nd instar (P<0.01) and 3rd/4th instars (P=0.004). The findings of this study indicate that the transfer of the SP introgressions from CU071026 into CU17NBL have reduced the SLW preference compared to CU071026. Further characterization will be needed to understand these results.