Phytotoxicity of Tagetes erecta L. and Tagetes patula L. on plant germination and growth

Abstract

This study evaluated the phytotoxic potential and antioxidant activity of Tagetes patula and Tagetes erecta, and total phenols and flavonoids of the extracts were quantified. Laboratory bioassays for both pre-and postemergence were performed in Lactuca sativa L. seeds and in the Allium cepa seeds test. The antioxidant activity was evaluated by DPPH radical scavenging and reducing power of iron, besides total phenols and flavonoids quantification in the extracts. Thus, was observed a reduction in the mitotic index when in compared with the negative control. Was observed also a reduction the germination and development of tested seedlings and was verified a considerable antioxidant potential and presence of flavonoids and phenolic compounds in the extracts. According to these results, it is possible to conclude that T. erecta and T. patula have phytotoxic compounds that may enhance and expand their use in the management of organic agriculture, mainly in vegetables.

Tagetes spp. Essential Oils and Other Extracts: Chemical Characterization and Biological Activity

“…Extracts obtained from T. erecta showed good insecticidal properties against aphids ( Aphidoidea ) and fall armyworm ( Spodoptera frugiperda ), which are responsible for the destruction of wild varieties of crops [ 150 , 151 ]. According to dos Santos et al [ 152 , 153 ], the species T. erecta and T. patula showed larvicidal and insecticidal properties with the possibility of the use of Tagetes extracts as an alternative to synthetic insecticides used against rice weevil ( Sitophilus zeamais ).…”

Phytotoxic Activity and Identification of Phytotoxic Substances from Schumannianthus dichotomus

“…However, in recent years, demand for organic farming has markedly increased all over the world. This system aims to grow crops using natural products rather than external inputs, enhancing the reduction of toxic residues and providing safe food [3,4]. To ensure sustainable organic farming, it is essential to use diversified techniques to control weeds rather than synthetic herbicides.…”

Allelopathic Potential and Active Substances from Wedelia Chinensis (Osbeck)

“…Organic farming emerged at the beginning of the 20th century as an alternative agricultural method to demote the hazardous effect of nonnatural herbicides on the environment and people [1,2]. Natural substances are used in organic farming, and at the same time, the use of synthetic substances is banned or severely restricted [3].…”