03402naa a2200277 a 450000100080000000500110000800800410001902200140006002400350007410000140010924501880012326000090031150007010032052018160102165300080283765300190284565300150286465300180287965300290289765300120292665300140293870000160295270000150296870000140298377301270299710626442022-01-18       2022    bl uuuu     u00u1 u    #d  a0022-20117 a10.1016/j.jip.2021.1077002DOI1 aSESSA, L.  aAlkane-priming of Beauveria bassiana strains to improve biocontrol of the redbanded stink bug Piezodorus guildinii and the bronze bug Thaumastocoris peregrinus.h[electronic resource]  c2022  aArticle history: Received 12 August 2021; Revised 1 November 2021; Accepted 22 November 2021; Available online 26 November 2021. This work was financed by Agencia Nacional de Investigación e Innovación (ANII, Uruguay) grant POS_NAC_2016_1_130245 and Instituto Nacional de Investigación Agropecuaria (INIA, Uruguay) Projects SA24 and SA47. Assistance of Mabel Pessio from INIA Estanzuela and Sofia Simeto from INIA Tacuarembó is acknowledged. Corresponding author: Sessa, L.; Laboratorio de Bioproducción, Plataforma de Bioinsumos, Instituto Nacional de Investigación Agropecuaria, Estación Experimental Wilson Ferreira Aldunate, Ruta 48, km 10, Canelones, Uruguay; email:lsessa@inia.org.uy  aABSTRACT. - Insect epicuticle hydrocarbons (CHC) are known to be important determinants in the susceptibility degree of insects to fungal entomopathogens. Five Beauveria bassiana (Balsamo) Vuillemin (Hypocreales; Clavicipitaceae) strains were phenotypically analyzed regarding their response to CHC nutrition and their pathogenicity and virulence towards high fungal-susceptible Thaumastocoris peregrinus (Carpintero and Dellapé) (Heteroptera: Thaumastocoridae) and low fungal-susceptible Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae), which are important hemipteran pests in eucalyptus and soybean plantations, respectively. Two of these strains, which were the most (ILB308) and the least (ILB299) virulent to P. guildinii, were also evaluated at gene expression level after growth on n-pentadecane, a P. guildinii epicuticular hydrocarbon. Beauveria bassiana hypervirulent strain ILB308 showed the lowest growth on most evaluated CHC media. However, this strain distinctively induced most of the analyzed genes involved in CHC assimilation, cuticle degradation and stress tolerance. Virulence towards low susceptibility P. guildinii was enhanced in both hypervirulent ILB308 and hypovirulent ILB299 strains after growth on n-pentadecane as the sole carbon source, whereas virulence enhancement towards high susceptibility T. peregrinus was only observed in the hypervirulent strain. Virulence enhancement towards P. guildinii could be mostly explained by a priming effect produced by CHC on the induction of some genes related to hydrocarbon assimilation in ILB299 and ILB308, such as cytochrome P450 genes (BbCyp52g11 and BbCyp52x1), together with adhesion and stress tolerance genes, such as hydrophobin (Bbhyd2) and catalase (Bbcatc) and glutathione peroxidase (Bbgpx), respectively.  © 2021  aBug  aEntomopathogen  aEucalyptus  aN-pentadecane  aPLATAFORMA DE BIOINSUMOS  aSoybean  aVirulence1 aPEDRINI, N.1 aALTIER, N.1 aABREO, E.  tJournal of Invertebrate Pathology, 2022, Volume 187, Article number 107700. doi: https://doi.org/10.1016/j.jip.2021.107700