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.

中文翻译：

---

内生真菌提取物：评价为光合作用和杂草生长抑制剂。

现代除草的一个中心支柱是发现了对人类和环境无毒且使用剂量低的新型除草剂。在植物和微生物中发现的天然产物非常适合这种情况，因为它们通常是无毒的并且具有多种生物学活性。在这项工作中，评价了菜豆（Diaporthe phaseolorum，Dp），青霉（Penicillium simplicissimum，Ps）和螺旋木霉（Trichodermaspire）（Ts）（甲醇提取物）在西番莲（Senna occidentalis）和大叶番薯（Ipomoea grandifolia）中的光合作用和植物生长抑制剂的性能。分别在西方葡萄球菌和大叶葡萄球菌中观察到Ts和Dp的最显着结果。Ts将PI（abs），ET0 / CS0，PHI（E0）和PSI0参数分别降低了64％，28％，40％和38％，这表明电子传输效率降低了。另外，Ts使芽长降低9％，影响植物的生长。Dp将PI（abs），ET0 / CS0和PHI（E0）参数分别降低了50％，20％，26％和22％，从而揭示了对PSII受体位点的抑制能力。此外，在发芽试验中，Dp使芽长度减少了50％。因此，基于内生真菌提取物的植物毒性行为可能在生物除草剂的进一步开发中充当有价值的工具，因为天然产物是替代商业除草剂的有趣替代品。