Tarbiat Modares University Journal of Crop Protection 2251-9041 14 3 2025 10 26 Allelopathic potential of Zea mays, Senna spectabilis, and Muntingia calabura for suppression of tea-associated weeds 267 280 27777 10.48311/jcp.2025.76150.0 EN Chandima Ranawana Department of Export Agriculture, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka. Kasun Jayalath Department of Export Agriculture, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka. Ewon Kaliyadasa Department of Export Agriculture, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka. Wasana Jeewanthi Department of Export Agriculture, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka. Bhagya Samarasinghe Department of Export Agriculture, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, 90000, Sri Lanka. Journal Article 2024 03 13 Abstract: Allelopathic potential of three plant species, namely, Zea mays, Senna spectabilis, and Muntingia calabura to control weeds was investigated via bioassays and field studies. The specific objectives were to identify the most phytotoxic plant extract, its effective concentration, the phytochemical extraction method, the allelochemical release mode, and the field efficacy in controlling weeds. Plant extracts were prepared with dry powders of leaves/husks in four concentrations (4, 6, 8, and 10% w/v) using hot and cold-distilled water. The modes of releasing allelochemicals (decomposition, volatilization, and leaching) were identified using pot bioassay, dish-pack, and sandwich methods, respectively. Lettuce Lactuca sativa was used as an indicator in bioassays. Meanwhile, the three most allelopathic extracts/materials were tested in the field by spraying and mulching. Results revealed no significant difference among hot and cold-water extractions (P > 0.05). The 10% concentration showed the highest phytotoxicity. M. calabura and S. spectabilis showed the highest phytotoxicity, evidenced by the lowest germination (22-23%), followed by Z. mays (44%). Leaching was prominent in S. spectabilis, as evidenced by the lowest germination (61%) and the highest inhibitory effects on radical (77%) and hypocotyl (71%) elongation. Volatilization was prominent in S. spectabilis and M. calabura, while decomposition was notable in Z. mays (leaves) and S. spectabilis. Mulching was more effective than spraying (10%, 450 ml m-2), with Z. mays mulching recording the lowest weed emergence, followed by M. calabura (77-84% weed dry weight reduction). In conclusion, S. spectabilis and M. calabura demonstrate high allelopathic potential, followed by Z. mays, highlighting their potential for eco-friendly weed control.

https://jcp.modares.ac.ir/article_27777_8f1ac1569697283fb7739acf854fef05.pdf