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Abstract

The intensive use of glyphosate in agricultural areas has increased the frequency of weeds that are resistant to herbicides. Thus, this study was aimed to assess the sensitivity and resistance level of Digitaria insularis (L.) Fedde (sourgrass) populations to glyphosate. Sixty two sourgrass populations were collected from the states of Paraná and São Paulo, Brazil, and subjected to glyphosate application at 1,080 and 2,160 g of acid equivalent (a.e.) · ha–1 in screening assays. Five sourgrass populations were selected, three of which are resistant and two of which are susceptible to glyphosate, to determine the resistance factors (RFs) through dose-response studies at two phenological stages of plant growth: the 2–4-leaf stages and the 2–4-tiller stage. The trials were conducted in a greenhouse in accordance with a completely randomized design. In both trials, the control was evaluated based on the score of the visual control symptoms (VC) and the percentage of dry matter (DM) in relation to those of the control (without application). In the screening test, the data obtained for the response variables were adjusted for frequency curves by following the regression model proposed by Gompertz. The results indicated low sensitivity of D. insularis to glyphosate in 100% of the samples from areas in which soybeans are tolerant to this herbicide. Populations with susceptible plants were found in fallow areas, pasture areas and sugar cane fields. Based on the values of VC50 and DM50, the maximum RF obtained among the populations was 15. More advanced stages of development make sourgrass control difficult, requiring doses that are 3.5 times greater than those at the initial stage.
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Bibliography

1. Asociación Latinoamericana De Malezas – ALAM. 1974. Recommendations on the unification of disease control evaluation. Journal of the Latin American Weed Association. 1: 6–38. (in Spanish)
2. Burgos N.R., Tranel P.J., Streibig J.C., Davis V.M., Shaner D., Norsworthy J.K., Ritz C. 2013. Review: confirmation of resistance to herbicides and evaluation of resistance levels. Weed Science 61 (1): 4–20. DOI: https://doi.org/10.1614/WS-D-12-00032.1
3. Carvalho S.J.P., Lombardi B.P., Nicolai M., López-Ovejero R.F., Christoffoleti P.J., Medeiros D. 2005. Dose-response curves to evaluate the control of weed emergence fluxes by imazapic. Planta Daninha 23 (3): 535–542. DOI: http://dx.doi.org/10.1590/S0100-83582005000300018. (in Portuguese)
4. Carvalho L.B., Hipólito H.C., Torralva F.G., Alves P.L.C.A., Christoffoleti P.J., De Prado R. 2011. Detection of sourgrass (Digitaria insularis) biotypes resistant to glyphosate in Brazil. Weed Science 59 (2): 171–176. DOI: https://doi.org/10.1614/WS-D-10-00113.1
5. Carvalho L.B., Alves P.L., González-Torralva F., Cruz-Hipolito H.E., Rojano-Delgado A.M., Prado R., Gil-Humanes J., Barro F., de Castro M.D. 2012. Pool of resistance mechanisms to glyphosate in Digitaria insularis. Journal of Agricultural and Food Chemistry 60 (2): 615–622. DOI: 10.1021/jf204089d
6. Christoffoleti P.J. 2002. Rate-response curves of resistant and susceptible Bidens pilosa L. biotypes to als-inhibitor herbicides. Scientia Agricola 59 (3): 513–519. DOI: https://doi.org/10.1590/S0103-90162002000300016 (in Portuguese)
7. CONAB. 2018. National Supply Company. Monitoring the Brazilian harvest: grains, ninth survey. 2018. Available on: https://www.conab.gov.br/safras/20861_fb79e3ca2b3184543c580cd4a4aa4. [Accessed on: 10 February 2019]
8. CTNbio. 2019. National Technical Commission on Biosafety. Commercial Releases. Available on: http://ctnbio.mcti.gov.br/liberacaocomercial?p_p_id=110_INSTANCE_SqhWdohU BvU&p_p_lifecycle=0&p_p_state=normal U_fileEntryId=2061402#/liberacao comercial/consultar-processo. [Accessed on: 01 January 2020] (in Portuguese).
9. Hall L.M., Stromme K.M., Horsman G.P. 1998. Resistance to acetolactate synthase inhibitors and quinclorac in a biotype of false cleavers (Galium spurium). Weed Science 46 (4): 390–396. DOI: https://doi.org/10.1017/S0043174500090780
10. Heap I. 2020. Herbicide resistant sourgrass globally (Digitaria insularis). Available on: http://www.weedscience.org/Summary/Species.aspx. [Accessed on: 01 April 2020]
11. Gemelli A., Oliveira Jr. R.S., Constantin J., Braz G.B.P., Jumes T.M.C., Oliveira Neto A.M., Dan H.A., Biffe D.F. 2012. Biology aspects of Digitaria insularis resistant to glyphosate and implications for its control. Revista Brasileira de Herbicidas 11 (2): 231–240. DOI: https://doi.org/10.7824/rbh.v11i2.186 (in Portuguese)
12. Gompertz B. 1825. On the nature of the function expressive of the law of human mortality, and on a new mode of determining the value of life contingencies. Philosophical Transactions of the Royal Society of London 115: 513–583.
13. Kissmann K.G., Groth D. 1997. Weed and Harmful Plants. 3rd ed. Tomo I. São Paulo, Brazil, 606 pp.
14. Lopez Ovejero R.F., Takano H.K., Nicolai M., Ferreira A., Melo M.S.C., Cavenaghi A.L. 2017. Frequency and dispersal of glyphosate-resistant sourgrass (Digitaria insularis) populations across brazilian agricultural production areas. Weed Science 65 (2): 285–294. DOI: https://doi.org/10.1017/wsc.2016.31
15. Melo M.S.C., Rocha L.J.F.N., Brunharo C.A.C.G., Nicolai M., Tornisiello V.L., Nissen S.J., Christoffoleti P.J. 2019. Sourgrass resistance mechanism to the herbicide glyphosate. Planta Daninha. Viços. 37: e019185746. DOI: https://doi.org/10.1590/s0100-83582019370100033
16. Mendonça G.S., Martins C.C., Martins D., Costa N.V. 2014. Ecophysiology of seed germination in Digitaria insularis (L.) Fedde. Revista Ciência Agronômica 45 (4): 823–832. DOI: https://doi.org/10.1590/S1806-66902014000400021
17. Mondo V.H.V, Carvalho S.J.P, Dias A.C.R., Júlio M.F. 2010. Light and temperature effects on the seed germination of four Digitaria weed species. Revista Brasileira de Sementes. 32 (1): 131–137. DOI: https://doi.org/10.1590/S0101-31222010000100015 (in Portuguese)
18. Reinert C.S., Prado A.B.C.A., Christoffoleti P.J. 2013. Comparative dose-response curves between sourgrass (Digitaria insularis) resistant and susceptible biotypes to glyphosate Revista Brasileira de Herbicidas. 12 (3): 260–267. DOI: https://doi.org/10.7824/rbh.v12i3.223 (in Portugese)
19. Rodrigues B.N., Almeida F.S. 2018. Herbicide Guide. Londrina, PR, Brazil, 764 pp.
20. Sammons R.D., Gaines T.A. 2014. Glyphosate resistance: state of knowledge. Pest Management Science 70 (9): 1367–1377. DOI: 10.1002/ps.3743
21. Seefeldt S.S., Jensen J.E., Fuerst, E.P. 1995. Log-logistic analysis of herbicide dose-response relationships. Weed Technology 9 (2): 218–227. DOI: https://doi.org/10.1017/S0890037X00023253
22. Silveira H.M., Langaro A.C., Cruz R.A., Sediyama T., Silva A.A. 2018. Glyphosate efficacy on sourgrass biotypes with suspected resistance collected in GR-crop fields. Acta Scientiarum, Agronomy: 40. DOI: http://dx.doi.org/10.4025/actasciagron.v40i1.35120
23. SYSTAT. 2013. Systat Software Products. Available on: https://systatsoftware.com/products/. [Access on: 11 february 2019]
24. Souza R.T.I., Velini E.D., Palladini L. 2007. Methodological aspects for spray deposit analysis by punctual deposit determination. Planta Daninha 25 (1): 195–202. DOI: https://doi.org/10.1590/S0100-83582007000100022 (in Portuguese)
25. Takano H.K., Oliveira Jr. R.S., Constantim J., Mangolim C.A., Machado M.F.P.S., Bevilaqua M.R.R. 2018. Spread of glyphosate-resistant sourgrass (Digitaria insularis): Independent selections or merely propagule dissemination? Weed Biology and Manegement 18: 50–60. DOI: https://doi.org/10.1111/wbm.12143
26. USDA. 2018. United States Department of Agriculture – Brazil – Agricultural Biotechnology Report. Avaliable on: http://usdabrazil.org.br/en/reports/agricultural-biotechnology-annual-5.pdf. [Acessed on: 10 February 2019]
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Authors and Affiliations

Jhonatan Diego Cavalieri
1
Renan Fonseca Nascentes
1
Matheus Mereb Negrisoli
1
Caio Antonio Carbonari
1
Carlos Gilberto Raetano
1

  1. Department of Plant Protection, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
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Abstract

The following work analyzes the effect of the composition of a hemp-lime composite on key mechanical and physical properties. The article contains results from testing the compressive strength, vapor permeability, and thermal conductivity of the composite, depending on the composition of the mix. The mixes differed from each other in binder composition and in the proportion of binder to hemp shives. The obtained results were compared with the results from other scientific literature. Based on this, conclusions were drawn that the binder composition is of secondary importance for the analyzed physical and mechanical properties of the hemp-lime composite. The main property that determines the values of the thermal conductivity coefficient as well as the compression strength is the density of the material, which depends on the proportion of binder to aggregate and the level of compaction of the mix. The value of the diffusion resistance coefficient of the analyzed material was very low regardless of the composition of the composite.

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Authors and Affiliations

Wojciech Piątkiewicz
Piotr Narloch
Barbara Pietruszka
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Abstract

This research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDMmembrane is described. Two main types (outside and inside types) ofEPDMmembranes are laboratory tested. The authors indicated that the EPDM membranes should differ in surface factures. Nevertheless, some manufacturers mark EPDM membranes on each roll (on the package only) without different permanent denotations on the EPDM membranes surfaces. This form of denotations can cause using problems – using the wrong types of the EPDM aprons in building partitions, because when the package is removed there is impossible to visually identify the type of EPDM membrane (outside or inside type) from the texture of the membrane surface. The experimental results of laboratory tests indicated using the wrong type of EPDM membrane in the inside aprons in building partitions in the investigated façade window system. The designed proportion of the sd values (the resistance to movement of water vapour) of inside and out-side EPDM façade membranes should be designed equally to about 3.0 (recommended value 4) to provide proper diffusion properties of partitions around windows in façade systems. The paper can provide scientists, engineers, and designers an experimental basis in the field of the EPDM membranes water vapour transmission properties applied to façades and windows systems.
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Authors and Affiliations

Andrzej Ambroziak
1
ORCID: ORCID
Sławomir Dobrowolski
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, St.Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland

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