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Effector proteins in Phakopsora pachyrhizi (Pp), the causative agent of Asian Soybean rust, are involved in the infection process. A previous study identified a rust effector Egh16-like family based expression profile during the interaction with soybean. Herein, we scrutinized available the Pp genomes to validate the predicted Egh16-like family of Pp and identify new family members. We described 22 members of the Egh16-like gene family in the Pp MT2006 genome and 18 in the UFV02 and K8108 genomes, highlighting a family expansion. Family members have a small signal peptide, conserved cysteine-rich R/Y/FxC motifs in the C-terminal region, and a virulence-related Egh16-like domain and were able to suppress PTI related responses in Benthamiana. Phylogenetic analysis placed the family members into eight clusters, with members induced during the early stages of rust infection. Members of clusters VI and VII are present in different copy numbers in Pp genomes and suppressed PAMP-related responses.

The loss of soybean yield to Brazilian producers because of a water deficit in the 2011-2012 season was 12.9%. To reduce such losses, molecular biology techniques, including plant transformation, can be used to insert genes of interest into conventional soybean cultivars to produce lines that are more tolerant to drought. The abscisic acid (ABA)-independent Dehydration Responsive Element Binding (DREB) gene family has been used to obtain plants with increased tolerance to abiotic stresses. In the present study, the rd29A:AtDREB2A CA gene from Arabidopsis thaliana was inserted into soybean using biolistics. Seventy-eight genetically modified (GM) soybean lines containing 2-17 copies of the AtDREB2A CA gene were produced. Two GM soybean lines (P1397 and P2193) were analyzed to assess the differential expression of the AtDREB2A CA transgene in leaves and roots submitted to various dehydration treatments. Both GM lines exhibited high expression of the transgene, with the roots of P2193 showing the highest expression levels during water deficit. Physiological parameters examined during water deficit confirmed the induction of stress. This analysis of AtDREB2A CA expression in GM soybean indicated that line P2193 had the greatest stability and highest expression in roots during water deficit-induced stress.