Endophytic fungal extracts: evaluation as photosynthesis and weed growth inhibitors

Abstract

A central pillar of modern weed control is the discovery of new herbicides which are nontoxic to humans and the environment and which have low application dosage. The natural products found in plants and microorganisms are well suited in this context because they are generally nontoxic and have a wide variety of biological activities. In this work, Diaporthe phaseolorum (Dp), Penicillium simplicissimum (Ps) and Trichoderma spirale (Ts) (methanolic extracts) were evaluated as photosynthesis and plant growth inhibitors in Senna occidentalis and Ipomoea grandifolia. The most significant results were observed for Ts and Dp in S. occidentalis and I. grandifolia, respectively. Ts reduced PI_(abs), ET₀/CS₀, PHI(E₀) and PSI₀ parameters by 64, 28, 40 and 38%, respectively, indicating a reduction on electron transport efficiency. Additionally, Ts decreased shoot length by 9%, affecting the plant growth. Dp reduced PI_(abs), ET₀/CS₀ and PHI(E₀) parameters by 50, 20, 26 and 22%, respectively, revealing the inhibition competency on PSII acceptor site. Furthermore, Dp decreased by 50% the shoot length on germination assay. Thus, the phytotoxic behaviors based on endophytic fungal extracts may serve as a valuable tool in the further development of a bioherbicide since natural products represent an interesting alternative to replace commercial herbicides.

Keywords:

• Bioherbicide
• chlorophyll a
• Diaporthe phaseolorum
• fluorescence
• Ipomoea grandifolia
• Penicillium simplicissimum
• Senna occidentalis
• Trichoderma spirale

Additional information

Funding

We gratefully acknowledge FAPEMAT (grant 0217830/2017 and 0250685/2017), CNPq (grant 430089/2016-3), CAPES and UFMT for financial support and fellowships.

Notes on contributors

Mariana S. Moura

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Jhuly W. F. Lacerda

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Kátia A. Siqueira

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Barbara S. Bellete

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Paulo T. Sousa

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Evandro L. Dall´Óglio

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Marcos A. Soares

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Lucas C. C. Vieira

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.

Olívia M. Sampaio

M.M.S., J.W.F.L., B.S.B., L.C.C.V and O.M.S performed the experiments, analyzed the data and designed the project, K.A.S. and M.A.S. performed and obtained the fungi extracts, E.L.D. and P.T.S.J worked on data curation. All authors commented and contributed to the preparation of the final manuscript.