The data were generated by the authors in independent experiments, all performed in the same conditions and installations. All the experiments were performed twice and the data corresponding with trials 1 and 2 of the same set was compared to allow combination in the statistical analysis. Each trial was performed with new and fresh nematodes and insects, Entomopathogenic nematodes (EPN) are excellent biocontrol agents against various insect pests. Novel biotechnological approaches can enhance their utility against insects above-ground, opening a new venue for selecting superior EPN against certain insects. We hypothesize that different populations of the same species but from different origins (habitat, ecoregion) will differ in their virulence. This study aimed to evaluate the virulence of various EPN populations against two pests of worldwide incidence and damage to high value crops: Frankliniella occidentalis (Thysanoptera: Thripidae) and Tuta absoluta (Lepidoptera: Gelechiidae). We tested 10 EPN populations belonging to three EPN species: Heterorhabditis bacteriophora (Koppert, MG-618b, AM-203, RM-102), Steinernema feltiae (Koppert, RS-5, AM-25, RM-107), and Steinernema carpocapsae (Koppert, MG-596a). Each EPN population was tested at two concentrations. Frankliniella occidentalis was tested at 160 and 80 IJs/cm2 and T. absoluta at 21 and 4 IJs/cm2. Control treatments followed the same experimental procedure but only adding distilled water. Overall, whenever different, higher IJs concentration resulted in lower adult emergence, higher larval mortality, and shorter time to kill the insects. Considering the low concentration, S. feltiae provided the best results for both insects and instars investigated, while H. bacteriophora and S. carpocapsae required a high concentration to reach similar or slightly better results. Differences among populations of each of the species were detected, but only the native populations of H. bacteriophora populations showed consistently higher control values against both insects/instar compared with the commercial one. Differences among S. feltiae and S. carpocapsae populations depended on the IJs concentration, insect, and instar. We consider S. feltiae a very promising species for their application against F. occidentalis and T. absoluta, with the Koppert population as the most consistent among the populations tested. Specific EPN-populations of S. carpocapsae and H. bacteriophora were good candidates against certain instar/insects at high concentrations. This study emphasized the importance of intraspecific variability for EPN virulence., Grants ICVV-CSIC and Koppert with the following references:
1) ref. 20194898 (ID CSIC 201912)
2) ref. 20200154 (ID CSIC 205137)
3) ref. 20202349 (ID CSIC 210825), 1) RCH is awarded by Ramon y Cajal contract award MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”: Grant RYC-2016-19939 from the Government of Spain
2) IVD is supported with a FPI-UR (2021) fellowship (Universidad de La Rioja, Spain).
3) MC is supported by a Moroccan scholarship for the Ministry of National Education, Vocational Training, Higher Education and Scientific Research, and the travel assistance associated with the grant
CSIC I-COOP + 2018 grant (COOPA20231).
4) MMGT is funded by the Program JAE-Intro CSIC call 2020 (JAEINT20_EX_0939).
5) MP and DL are funded by an introduction to research fellowship from Government of La Rioja (CAR 2020)., Peer reviewed

Experiment performed in the lab, following details described in the publication (http://hdl.handle.net/10261/240920 / https://doi.org/10.3390/insects12050448), Grants ICVV-CSIC:

Ministry of Science and Innovation (PID2019-104112RB-I00) funded by MCIN/AEI/10.13039/501100011033.

Support for researchers:

1) RCH is awarded by Ramon y Cajal contract award MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”: Grant RYC-2016-19939 from the Government of Spain
2) IVD is I.V.-D. funded by ADER I + D + i (2019) fellowship by the Rioja Agency of Economic Development
(La Rioja, Spain) and by FPI-UR (2021) fellowship (Universidad de La Rioja, Spain).
4) MMGT is funded by the Program JAE-Intro CSIC call 2020 (JAEINT20_EX_0939).
5) R.B.-P. was supported by the pre-doctoral contracts CAR-2018 (Department of Economic Development and Innovation of the Government of La Rioja)., Peer reviewed

Experiment performed in the lab, following details described in the publication: https://doi.org/10.3390/insects12111033 / http://hdl.handle.net/10261/262517, Grants ICVV-CSIC:

Ministry of Science and Innovation (PID2019-104112RB-I00) funded by MCIN/AEI/10.13039/501100011033.

Support for researchers:

1) RCH is awarded by Ramon y Cajal contract award MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”: Grant RYC-2016-19939 from the Government of Spain
2) IVD is I.V.-D. funded by ADER I + D + i (2019) fellowship by the Rioja Agency of Economic Development (La Rioja, Spain) and by FPI-UR (2021) fellowship (Universidad de La Rioja, Spain).
3) MP is funded by an introduction to research fellowship from the Government of La Rioja (CAR 2020).
4) MC was supported by the travel assistance is associated with the CSIC I-COOP+ 2018 grant (COOPA20231) and a Moroccan scholarship for the Ministry of National Education, Vocational Training, Higher Education, and Scientific Research
5) RBP was supported by the pre-doctoral contracts CAR-2018 (Department of Economic Development and Innovation of the Government of La Rioja)., Peer reviewed

Experiment performed in the lab, following details described in the publication: http://dx.doi.org/10.1016/j.jip.2021.107620 / http://hdl.handle.net/10261/261936, Grants ICVV-CSIC:

1) CSIC I-COOP + 2018 grant (COOPA20231)

2) Associated funds of Ramon y Cajal contract award MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”: Grant RYC-2016-19939 from the Government of Spain

Support for researchers:

1) MC was supported by the travel assistance is associated with the CSIC I-COOP+ 2018 grant (COOPA20231) and a Moroccan scholarship for the Ministry of National Education, Vocational Training, Higher Education, and Scientific Research
2) RBP was supported by the pre-doctoral contracts CAR-2018 (Department of Economic Development and Innovation of the Government of La Rioja).
3) IVD was funded by ADER I + D + i (2019) fellowship by the Rioja Agency of Economic Development (La Rioja, Spain) and by FPI-UR (2021) fellowship (Universidad de La Rioja, Spain).
4) RCH was awarded by Ramon y Cajal contract award MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”: Grant RYC-2016-19939 from the Government of Spain, Peer reviewed

Experiment performed in the lab, following details described in the publication https://doi.org/10.1007/s10526-023-10212-7, Grant PID2019-104112RB I00 from Ministry of Science and Innovation (MCIN/AEI/10.13039/50110001103).

Grant RYC-2016-19939 funded by Ministry of Science and Innovation (MCIN/
AEI/ 10.13039/501100011033) and “ESF Investing in your future”.
The predoctoral contract FPI-UR 2021 (University of La Rioja) support IVD, Peer reviewed

Experiment performed in the laboratory, following details described in the publication, The MCIN/AEI/ 10.13039/501100011033 and “ESF Investing in your future” supported the grant RYC-2016-19939

The Instituto de Estudios Riojanos (IER, Government of La Rioja, Spain, ref.21/2021).

Support for researchers:

RBP was supported by a FPI-CSIC-CAR grant Department of Economic Development and Innovation of the Government of La Rioja, Spain

IVD was supported by a FPI-UR grant (UR, 2020)

RCH was supported by the RYC-2016-19939 funded by MCIN/AEI/ 10.13039/501100011033 and “ESF Investing in your future”., Peer reviewed